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Professor Ravi Naidu

Laureate Professor and Director

Global Centre for Environmental Remediation

Remediation and Risks: a world without contamination

Professor Ravi Naidu is a global leader in contamination studies, studying agricultural and industrial impacts on the environment.

His research has led to the implementation of policy directives for governments and new technology to manage and remediate polluted groundwater and soil, both in Australia and abroad.

Ravi is also the Managing Director of the Cooperative Research Centre for Contamination, Assessment and Remediation of the Environment (CRC CARE), an independent organisation that performs research, develops technologies and provides policy guidance for assessing, cleaning up and preventing contamination of soil, water and air.  At the University of Newcastle, Ravi leads the Global Centre for Environmental Remediation (GCER), where he continues to implement his vision to safeguard the environment for future generations.

Shaping the world

As science speeds forward, Ravi acknowledges that public policy doesn't always keep up. With more than two decades working in the field of contaminants, including an esteemed chief investigator role with Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO), Ravi has made extensive contributions to national and global paradigms of risk assessment and remediation of contaminated sites.

"I have spent a lot of time developing a consensus amongst industry, regulators, Environmental Protection Authorities and researchers relating to contaminants," Ravi points out.

"As well as to remediate sites, a lot of work is required on the policy front."

"When I began my career, there was no remediation industry; my work has led to an exponential increase in the number of people working in remediation," Ravi states humbly.

This industry is now worth $3 billion dollars annually and employs thousands of people.

A systems-based approach to risk

Focusing on two broad categories, Ravi's meticulous analyses investigate contaminants from agriculture and industry and their relationships with receptors.

"The receptor could be the environment, or human," Ravi says.

"My investigations look at the presence of contaminants in the environment, how they interact in the environment, and the route or path they take to receptors."

"Initially the focus of our work was on agriculture," Ravi observes.

"But many of the industrial activities over the past 50 years have led to significant contamination of the environment."

"Now the focus of our investigations – to a very large extent – is industrial contaminants and this is largely driven by the industries themselves."

Ravi's approach to this work has been to adopt whole-of-system inquiries to ensure the risks of contaminants are fully assessed and managed, whether they are in soil, groundwater or the urban environment.

"When assessing a contaminated site you assess the receptors, what the pathways to those receptors are, and what needs to be done to minimise exposure," Ravi confirms.

Ravi notes the importance of this, given the severe health effects of some contaminants such as asbestos, arsenic, cadmium and mercury.

The Professor's approach is seeing GCER develop a new model in conjunction with CRC CARE to quantify risk posed by on-site contaminants.

"Until recently, the predictive tool that has been used to assess risk - and which is still being used - is a database based on a lot of assumptions."

"Whenever you use assumptions, the output from the predictive tool can be quite conservative, and conservatism means you might end up remediating sites which do not require it."

"This new model will minimise uncertainties and save a lot of money for industries."

CRC CARE and GCER: caring and sharing knowledge

CRC CARE began in 1999 when Ravi initiated dialogue with industries and government departments dealing with contaminants.

"It took four years for industries to appreciate there was a need for a national Centre of Excellence to become a one-stop shop for contaminants."

The Centre, which brings together major companies, government departments and Environmental Protection Authorities, was established in 2005 by a competitive bid to the Commonwealth and is on track to become a Centre of Excellence beyond the year 2020.

In 2015, the University of Newcastle invited Ravi to be Global Innovation Chair and Director of GCER.

"GCER reaches organisations in Australia and beyond from a capacity-building perspective," Ravi notes.

This entails training students as well as developing solutions for complex contamination problems.

"CRC CARE and GCER are safeguarding a clean environment for future generations," Ravi attests.

"Satisfaction is knowing you have helped train people who are able to clean up the mess we have created and prevent future degradation of our environment."

Technology targeting toxins

Ravi has patented seven technologies to safeguard the environment and human health, including a product to remediate the toxic chemicals left behind by firefighting foams.

"No technology was available to help clean up wastewater and impacted soil, generated by firefighters when they train," Ravi declares.

"CRC CARE developed a new patented technology to fix this, utilising a naturally occurring material modified with a nontoxic chemical."

"This product can irreversibly and selectively capture toxic substances present in wastewater."

"Thus, the water that comes out is clean because of our filtration processes."

The technology is being scaled up for field applications with plants operating at a number of remediation sites.

Proactive Global Research

Working globally, CRC CARE's centre in China is enabling Ravi to collaborate with a number of scientists and engineers, to train locals to develop solutions for environmental contamination problems.

"We have developed a technology, named pooCARE, which helps convert piggery waste into biogas," Ravi laughs.

"We have a very strong network in the region and our vision is to extend our Centres to other countries."

"The only way to move forward is to build the capacity in these countries, particularly developing nations, to deal with contamination issues."

Related links

Ravi Naidu

Remediation and Risks: a world without contamination

Professor Ravi Naidu is a global leader in contamination studies, studying agricultural and industrial impacts on the environment.

Read more

Career Summary

Biography

Professor Ravi Naidu is the Chief Executive Officer, Managing Director and Chief Scientist of the Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE). Professor Naidu was also the Founding Director of the Centre for Environmental Risk Assessment and Remediation (CERAR).

He has researched environmental contaminants, bioavailability, and remediation for over 25 years and has gained advanced leadership and management experience in environmental sustainability throughout this period. Professor Naidu has co-authored 440 refereed journal articles and seven patents, and co-edited 11 books and 66 book chapters in the field of soil and environmental sciences. He has also supervised over 35 PhD completions.  Of the seven patents that he has joint recognition for, two are now fully commercialized with remediation plants operating in Townsville, Perth and Adelaide treating contaminated waste water.  Remediation technology for the management and cleanup of soils contaminated with firefighting foam and chlorinated hydrocarbon contaminated ground water are used as proprietary technology and used for remediation at a number of sites.

Professor Naidu's publications have been cited more than 14,800 times (Google Scholar and Google h index 57) and i10 index of 265.

Professor Naidu was instrumental in developing a network of scientists working on contamination – Soil Contamination Research Australasia Pacific (SCRAP), now titled the Australian Remediation Industry Cluster (ARIC). As part of this network he has independently raised funds for research and training in the Asia region. Over the last 10 years he has run more than 20 workshops, 5 international conferences and raised more than $170M cash (includes CRC CARE funding) for research in this region. The network has led to the establishment of similar groupings of people within the regional countries and now has over 4000 members across the region.

In recognition of his contribution to environmental research he was awarded a Gold Medal in environmental science in 1998 by Tamil Nadu Agricultural University (TNAU).  He is an elected Fellow of the Soil Science Societies of America (2000), New Zealand (2004) and Agronomy Society of America (2006). In 2012 he was chosen as a winner of the Soil Science Society of America's International Soil Science Award, and in 2013 was elected a Fellow of the American Association for the Advancement of Science. He is Chair of the International Committee on Bioavailability and Risk Assessment and was Chair of the Standards Australia Technical Committee on Sampling and Analyses of Contaminated Soils (1999-2007), Chair of the International Union of Soil Sciences Commission for Soil Degradation Control, Remediation and Reclamation (2002-10), President of the International Society on Trace Element Biogeochemistry (2005-07) and sitting member of the Victorian EPA Contaminated Sites Auditor panel. In recognition of his contributions to agricultural and allied sciences, he was awarded honorary DSc by Tamil Nadu Agricultural University in December 2013 and inaugural Banksia CEO award in the same year for his outstanding contribution to environmental sustainability research.

Research Expertise
Professor Naidu’s current research focuses on contaminated soil, water and potential impacts of contaminants on human health. Professor Naidu’s vision is to expand his current research on the environment to China and the Asia region through collaboration and the development of a Centre of Excellence an environmental risk assessment and remediation in China. The focus of such a Centre will be the development and worldwide marketing of environment technology. 

Qualifications

  • Doctor of Philosophy, Massey University - NZ
  • Master of Science, University of the South Pacific
  • Doctor of Science, Tamil Nadu Agricultural University Coimbatore

Keywords

  • Environmental Science
  • Soil Science

Fields of Research

Code Description Percentage
440704 Environment policy 100

Professional Experience

UON Appointment

Title Organisation / Department
Global Innovation Chair and Director University of Newcastle
Global Centre for Environmental Remediation
Australia

Academic appointment

Dates Title Organisation / Department
1/1/2014 -  Editorial Board - Environment Technology Innovation Environment Technology Innovation
Australia
1/1/2010 -  Editorial Board - Journal of Soils and Sediments Journal of Soils and Sediments
Australia
1/1/2008 -  Editorial Board - Environment Geochemistry and Health Journal Environment Geochemistry and Health Journal
Australia
1/1/2008 -  Membership - Contaminated Site Steering Committee - BHP Billiton Iron Ore Division Contaminated Site Steering Committee - BHP Billiton Iron Ore Division
Australia
1/1/1996 -  Membership - Contaminated Sites Auditor Panel Member, EPA VIC Contaminated Sites Auditor Panel Member, EPA VIC
Australia
1/1/1996 -  Membership - Global Committee on Bioavailability and Risk Assessment Global Committee on Bioavailability and Risk Assessment
Australia
1/1/1995 -  Membership - Executive Committee, Environmental Geochemistry of Tropical Soils Executive Committee, Environmental Geochemistry of Tropical Soils
Australia
1/1/1994 -  Membership - International Committee on Biogeochemistry of Trace Elements International Committee on Biogeochemistry of Trace Elements
Australia
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Publications

For publications that are currently unpublished or in-press, details are shown in italics.


Book (20 outputs)

Year Citation Altmetrics Link
2023 Naidu R, Inorganic Contaminants and Radionuclides (2023)

Inorganic Contaminants and Radionuclides is a single reference covering common inorganic contaminants in detail, including their distribution in the environment, challenges linked... [more]

Inorganic Contaminants and Radionuclides is a single reference covering common inorganic contaminants in detail, including their distribution in the environment, challenges linked to management, geogenic sources, anthropogenic sources, exposure and effects, international agreements and legislation relating to the contaminant, remediation options and global case studies. In addition, the book provides summaries of contaminated sites and key details about contaminants to present a more comprehensive understanding and improve remediation and management practices. The book's clear, consistent organization makes it a valuable resource for researchers, students and practitioners working in environmental science, environmental management and environmental engineering. One of the major constraints to assessing and remediating contaminated sites is the lack of awareness of the extent and severity of contaminated sites amongst the community, regulators, policymakers, industry operators, university graduates and environmental managers. This book helps to manage these constraints.

DOI 10.1016/C2020-0-03802-8
2018 Bolan N, Spoil to Soil: Mine Site Rehabilitation and Revegetation 1st Edition by N.S. Bolan (Editor), M.B. Kirkham (Editor), Y.S. Ok (Editor), CRC Press, USA (2018)
Co-authors Nanthi Bolan, Girish Choppala
2018 Naidu R, Foreword (2018)
DOI 10.1016/B978-0-12-812986-9.06001-2
2018 Naidu R, Birke V, Permeable Reactive Barrier, CRC Press
DOI 10.1201/9781351228886
2015 Surampalli RY, Zhang TC, Tyagi RD, Naidu R, Gurjar BR, Ojha CSP, et al., Carbon capture and storage: Physical, chemical, and biological methods (2015)

Sponsored by the Carbon Capture and Storage Task Committee of the Technical Committee on Hazardous, Toxic, and Radioactive Waste Engineering of the Environmental Council of EWRI C... [more]

Sponsored by the Carbon Capture and Storage Task Committee of the Technical Committee on Hazardous, Toxic, and Radioactive Waste Engineering of the Environmental Council of EWRI Carbon Capture and Storage: Physical, Chemical, and Biological Methods presents comprehensive information on the principles of carbon capture and sequestration (CCS). Among the various climate change mitigation strategies currently being explored, CCS technology allows for the continuous use of fossil fuels and provides time to make a changeover to other energy sources in a systematic way. Many factors decide CCS applicability worldwide, such as technical development, overall potential, flow and shift of the technology to developing countries and their capability to apply the technology, regulatory aspects, environmental concerns, public perception, and costs. This book provides in-depth information on the principles of CCS technology, different environmental applications, recent advances, critical analysis of new CCS methods and processes, and directions toward future research and development of CCS technology. Topics include:carbon dioxide sequestration and leakage; monitoring, verification, and accounting of carbon dioxide in different settings; carbon reuses for a sustainable future; applications of CCS for the coal-powered electricity industry; carbon dioxide scrubbing processes and applications; carbon sequestration via mineral carbonation; carbon burial and enhanced soil carbon trapping; algae-based carbon capture; carbon immobilization enhanced by photosynthesis; enzymatic sequestration and biochar technology for CCS; carbon sequestration in the ocean; and modeling of carbon dioxide storage in deep geological formations. Engineers, scientists, students, government officers, process managers, and practicing professionals will find this book an essential reference on carbon capture and sequestration technology.

DOI 10.1061/9780784413678
Citations Scopus - 9
2014 Naidu R, Birke V, Permeable reactive barrier: Sustainable groundwater remediation (2014)

Remediation of groundwater is complex and often challenging. But the cost of pump and treat technology, coupled with the dismal results achieved, has paved the way for newer, bett... [more]

Remediation of groundwater is complex and often challenging. But the cost of pump and treat technology, coupled with the dismal results achieved, has paved the way for newer, better technologies to be developed. Among these techniques is permeable reactive barrier (PRB) technology, which allows groundwater to pass through a buried porous barrier that either captures the contaminants or breaks them down. And although this approach is gaining popularity, there are few references available on the subject. Until now. Permeable Reactive Barrier: Sustainable Groundwater Remediation brings together the information required to plan, design/model, and apply a successful, cost-effective, and sustainable PRB technology. With contributions from pioneers in this area, the book covers state-of-the-art information on PRB technology. It details design criteria, predictive modeling, and application to contaminants beyond petroleum hydrocarbons, including inorganics and radionuclides. The text also examines implementation stages such as the initial feasibility assessment, laboratory treatability studies (including column studies), estimation of PRB design parameters, and development of a long-term monitoring network for the performance evaluation of the barrier. It also outlines the predictive tools required for life cycle analysis and cost/performance assessment. A review of current PRB technology and its applications, this book includes case studies that exemplify the concepts discussed. It helps you determine when to recommend PRB, what information is needed from the site investigation to design it, and what regulatory validation is required.

Citations Scopus - 22
2014 Naidu R, Birke V, Preface (2014)
2014 Naidu R, Birke V, Preface (2014)
Citations Scopus - 4
2008 Naidu R, Chemical Bioavailability in Terrestrial Environments, Elsevier Science Limited, Amsterdam, 809 (2008) [A3]
2008 Singh N, Sethunathan N, Megharaj M, Naidu R, Chapter 5 Bioavailability of sorbed pesticides to bacteria: An overview (2008)
DOI 10.1016/S0166-2481(07)32005-9
Citations Scopus - 9
Co-authors Megh Mallavarapu
2008 Megharaj M, Naidu R, Chapter 11 Bioavailability and toxicity of contaminant mixtures to soil biota (2008)
DOI 10.1016/S0166-2481(07)32011-4
Citations Scopus - 5
Co-authors Megh Mallavarapu
2008 Wilson SC, Naidu R, Organic contaminant speciation and bioavailability in the terrestrial environment, Elsevier, Oxford, UK, 42 (2008)
DOI 10.1016/S0166-2481(07)32010-2
Citations Scopus - 10
2008 Naidu R, Chemical Bioavailability in Terrestrial Environments, Elsevier Science Limited, Amsterdam, 809 (2008) [A3]
2006 Naidu R, Managing Arsenic in the Environment From Soil to Human Health, Science Pub Incorporated, 656 (2006)
2005 Prasad MNV, Sajwan KS, Naidu R, Trace elements in the environment: Biogeochemistry, biotechnology, and bioremediation (2005)

New analytical techniques have enhanced current understanding of the behavior of trace and ultratrace elements in the biogeochemical cycling, chemical speciation, bioavailability,... [more]

New analytical techniques have enhanced current understanding of the behavior of trace and ultratrace elements in the biogeochemical cycling, chemical speciation, bioavailability, bioaccumulation, and as applied to the phytoremediation of contaminated soils. Addressing worldwide regulatory, scientific, and environmental issues, Trace Elements in the Environment explores these frontiers, including biotechnological aspects of metal-binding proteins and peptides and phytoremediation strategies using trees, grasses, crop plants, aquatics, and risks to ecological and human health. Discussing trace elements in the holistic environment, this book covers advances in state-of-the-art analytical techniques, molecular biotechology, and contemporary biotechnology that enhances knowledge of the behavior of trace elements in the biogeosphere and at the cellular and molecular level. The editors and their hand-picked panel of contributors provide authoritative coverage of trace elements in the environment. They highlight cutting-edge applications of emerging strategies and technologies to the problems of trace elements in the environment. The editors discuss emerging areas such as bacterial biosorption of trace elements, processes, and applications of electroremediation of heavy metals-contaminated soils, application of novel nanoporous sorbents for the removal of heavy metals, metalloids, and radionuclides. The book focuses on the effects of increasing levels of trace elements on ecological and human health, evaluates the effectiveness of methods of phytoremediation, and covers risk assessment, pathways, and trace element toxicity. Containing more than 150 illustrations, tables, photographs, and equations, the book¿s coverage spans the entire body of knowledge available about how and why plants interact with metals and other trace elements.

Citations Scopus - 37
2003 Kamaludeen SPB, Megharaj M, Juhasz AL, Sethunathan N, Naidu R, Chromium-microorganism interactions in soils: Remediation implications, SPRINGER, 72 (2003)
DOI 10.1007/0-387-21728-2_4
Citations Scopus - 156Web of Science - 120
Co-authors Megh Mallavarapu
1999 Naidu R, Naidu S, Jackson P, McLaren RG, Sumner ME, Application of capillary electrophoresis to anion speciation in soil water extracts, ACADEMIC PRESS INC, 20 (1999)
DOI 10.1016/S0065-2113(08)60912-8
Citations Scopus - 3Web of Science - 2
1998 Smith E, Naidu R, Alston AM, Arsenic in the soil environment: A review, ELSEVIER ACADEMIC PRESS INC, 47 (1998)
DOI 10.1016/S0065-2113(08)60504-0
Citations Scopus - 575Web of Science - 507
1995 Naidu R, Sumner ME, Rengasamy P, Australian Sodic Soils Distribution, Properties and Management, CSIRO Publishing, 351 (1995)
1995 Harter RD, Naidu R, Role of metal-organic complexation in metal sorption by soils, ELSEVIER ACADEMIC PRESS INC, 45 (1995)
DOI 10.1016/S0065-2113(08)60541-6
Citations Scopus - 246Web of Science - 200
Show 17 more books

Chapter (71 outputs)

Year Citation Altmetrics Link
2023 Sanderson P, Bahar MM, Biswas B, Naidu R, 'Remediation of metals and organic contaminants in soil', Encyclopedia of Soils in the Environment, Elsevier, Elsevier 333-343 (2023)
DOI 10.1016/B978-0-12-822974-3.00247-0
Co-authors Mezbaul Bahar, Bhaba Biswas
2023 Haynes RJ, Naidu R, 'Phosphorus An essential input for agriculture yet a key pollutant of surface waters', Inorganic Contaminants and Radionuclides 405-426 (2023)

While phosphorus (P) applications are essential for profitable crop and livestock production, agricultural watersheds represent a key nonpoint source of P inputs to waterways. Pho... [more]

While phosphorus (P) applications are essential for profitable crop and livestock production, agricultural watersheds represent a key nonpoint source of P inputs to waterways. Phosphorus is present in soils in both inorganic and organic forms and the quantity present in a soil solution at any one time is characteristically low (<20mM). There is a critical soil test value for a crop, soil, and farming system where a higher level gives no increase in yield, and below that, yield decreases. Once the critical P level is reached, only maintenance P applications are necessary (to replace the P removed in the harvested crop) and fertilizer P use efficiency is near 100% (when use of residual fertilizer P over the years following application is accounted for). Increasing extractable P above the critical level is an unnecessary expense and can often contribute to losses of P to surface waters. The major loss of P from agriculture is as particulate inorganic and organic P present in runoff. Often, runoff comes from only a small portion of a watershed in relatively few storms. Vulnerable sites can be assessed with the use of P indices, which account for both source and transport factors. A wide range of best management practices is available to farmers to control both sources of P (e.g., management of extractable P levels plus fertilizer and manure P application rates, timing, and placement) as well as the processes by which P is transported from agricultural land (e.g., conservation tillage, cover crops, artificial drainage, grassed waterways, conservation buffers, irrigation management). To minimize P losses from agriculture, sound extension and education programs are required while farmers need practical information and incentives to implement best management practices.

DOI 10.1016/B978-0-323-90400-1.00007-0
2023 Naidu R, Biswas B, 'Introduction to inorganic contaminants and radionuclides: Global issues and challenges', Inorganic Contaminants and Radionuclides 1-10 (2023)

Inorganic contaminants, including heavy metal, metalloid, and radionuclides, are a conventional and emerging group of pollutants. Therefore, much of their effect on human health a... [more]

Inorganic contaminants, including heavy metal, metalloid, and radionuclides, are a conventional and emerging group of pollutants. Therefore, much of their effect on human health and environmental quality is known, and lots are emerging. Overall, these groups of contaminants pose health risk once exposed via contact, dust inhalation, or food chain. This risk can be mortality or morbidity. Remediation technologies are available, but considering improvements like climate change adaptation is necessary. This chapter sweeps some insights into inorganic contaminants relating their definition, exposure, guideline values and remediation technologies. Specific members of these contaminant groups are extensively discussed in the subsequent chapters.

DOI 10.1016/B978-0-323-90400-1.00008-2
Co-authors Bhaba Biswas
2023 Vinceti M, Filippini T, Biswas A, Michalke B, Dhillon KS, Naidu R, 'Selenium: A global contaminant of significant concern to environment and human health', Inorganic Contaminants and Radionuclides 427-480 (2023)

Selenium (Se) is one of the most interesting and controversial elements found in the environment. It has long attracted interest due to its strong toxicity and potential carcinoge... [more]

Selenium (Se) is one of the most interesting and controversial elements found in the environment. It has long attracted interest due to its strong toxicity and potential carcinogenicity, while more recently it garnered interest as an essential nutrient, as a cofactor of selenoproteins, and due to the claim of a beneficial effect against cancer and other chronic diseases, which was recently found to be unwarranted. Selenium is ubiquitous in the environment, being present particularly in rocks, soils, combustion sources, such as smoking and industrial emissions, and water bodies, and therefore living organisms can be overly exposed to it. Selenium is found in several valence states and organic and inorganic compounds, and exposure is generally done by determining overall Se, its species and the selenoproteins in environmental and biological samples. Examples are serum and plasma, urine, hair and nails, and cerebrospinal fluid Se and Se species concentrations. The environmental effects and health outcomes attributable to both Se deficiency and excess, in animals and humans, have been the subject of a large number of studies, and attracted strong interest in environmental sciences and environmental health, also fueling considerable debate. While little evidence of adverse effects of Se deficiency has been detected so far, except for a cardiomyopathy described in some parts of China, a number of serious effects have been reported or suggested by human and animal studies, particularly those carried out in seleniferous areas and by those with experimental design, such as randomized controlled trials. Legislation and recommendations to control Se exposure and avoid the risk of overexposure widely differ throughout the world, and most of them need to be updated taking into account the most recent epidemiological and toxicological evidence. This is particularly due to the toxic effects on human health of even unexpectedly small doses of Se and some selenoproteins, such as type 2 diabetes, dermatological alterations, liver toxicity, endocrine alterations, and neurological disease. Due to the potential contamination of the environment, particularly soil, food, and water with excessive amounts of Se, effective remediation approaches and technologies are being devised and need to be implemented.

DOI 10.1016/B978-0-323-90400-1.00018-5
Citations Scopus - 1
2023 Rahman Z, Sanderson P, Naidu R, 'Chromium: A pervasive environmental contaminant and its removal through different remediation techniques', Inorganic Contaminants and Radionuclides 69-94 (2023)

Chromium (Cr) is a well-known pervasive element that predominantly exists as Cr(III) and Cr(VI) in the environment. Of these two species, the latter form is of great concern due t... [more]

Chromium (Cr) is a well-known pervasive element that predominantly exists as Cr(III) and Cr(VI) in the environment. Of these two species, the latter form is of great concern due to its mobility, solubility, and toxicity. Both species are easily transformable in the environment under different chemical influences. The natural sources of Cr are ultramafic rocks and serpentine soils. However, the main concern of Cr contamination arises due to anthropogenic activities such as chrome-based tanneries and electroplating industries. The detoxification of Cr is essential as its presence is detrimental to all kinds of living organisms and leads to the ecosystem degradation. Different strategies for the remediation of Cr(VI) include physiochemical and biological processes. Notable techniques for its removal are reduction process, precipitation, solvent extraction, pHotocatalysis, electrochemical methods, electrokinetic process, ion exchange method, adsorption, and membrane filtration. However, the main treatment option is immobilization by involving redox reaction either through chemical reduction or biological reduction using enzymes. In these contexts, the present chapter gives a detailed overview of the chemistry, sources, contamination, fate, and dynamics of Cr in the environment, and discusses different remediation options.

DOI 10.1016/B978-0-323-90400-1.00015-X
2023 Halim MA, Naidu R, 'Cyanide contamination of soil and water: Sources, toxicity, and potential remediation strategies', Inorganic Contaminants and Radionuclides 375-403 (2023)

Cyanide is a silent killer present in high concentrations in mine waste tailings, generating carbon monoxide and other cyanogenic compounds. Nevertheless, it is a dynamic reagent ... [more]

Cyanide is a silent killer present in high concentrations in mine waste tailings, generating carbon monoxide and other cyanogenic compounds. Nevertheless, it is a dynamic reagent used globally in the mining, cosmetics, pharmaceutical, and food processing industries. The compound hydrogen cyanide, generated from cyanide, is 35 times more toxic than carbon monoxide and can cause mitochondrial dysfunction in humans and animals, potentially leading to cardiac arrest, heart attack, and death. The current paper presents the various sources, toxicology, fate, behaviors, and potential remediation techniques of cyanide, revealing that the detection of on-site cyanide is crucial for the remediation of cyanide-contaminated sites. Various reusable nanostructured materials can transform sites from high to low cyanide concentrations. Moreover, biological agents such as bacteria and fungi may be deployed together with reusable nanostructured materials to ensure the sustainable remediation of cyanide-contaminated sites and the potential circular management of this carcinogenic, hazardous chemical in water and soil ecosystems. This chapter summarizes the sources, global scenario, and ecotoxicity of cyanide and potential remediation techniques for cyanide-contaminated sites.

DOI 10.1016/B978-0-323-90400-1.00017-3
2023 Selvakumar R, Naidu R, 'Radionuclide removal technologies involving nano-bio concepts for contaminated water environments', Inorganic Contaminants and Radionuclides 483-501 (2023)

Radionuclides are released into the environment as a result of natural and anthropogenic activities. Considering their impact on environment and humans, flora and fauna, removal o... [more]

Radionuclides are released into the environment as a result of natural and anthropogenic activities. Considering their impact on environment and humans, flora and fauna, removal of radionuclides from the environment is vital. In many environments, water is widely affected by radionuclide contaminants through both natural and anthropogenic sources. In this chapter, the focus is on the latest advances in removal technologies involving nano-bio concepts. Materials and technologies where the nanomaterial and biological materials/organisms have been used on an integrated approach are discussed. Bio-ceramic materials, protein-nano interaction, biomass-nano interaction, microbial-nanomaterial based interaction and biopolymer-nanomaterial interaction with respect to radionuclide removal from water sources are investigated in detail.

DOI 10.1016/B978-0-323-90400-1.00004-5
2023 Rahman MA, Deb AK, Abbasi S, Bari ASMF, Zaman KAU, Rahman MM, et al., 'Arsenic', Inorganic Contaminants and Radionuclides 13-40 (2023)

Arsenic (As) is a poisonous metalloid and recognized as a Group I human carcinogen by the International Agency for Research on Cancer (IARC). Arsenic often exists in groundwater a... [more]

Arsenic (As) is a poisonous metalloid and recognized as a Group I human carcinogen by the International Agency for Research on Cancer (IARC). Arsenic often exists in groundwater and surface water, oceanic and inland deposits, rocks, soils, and biota at variable concentrations. Over the last few decades, As contamination has been augmented noticeably due to both natural and anthropogenic sources. Arsenic contamination in groundwater is currently a major global environmental catastrophe, which affects over 200 million people in 107 countries and causes various health complications including cancer. Therefore, updated information regarding the sources, chemical form, bioavailability, extent and severity, food safety and regulation, remediation, and management of As is essential. In this chapter, we accumulated the detailed sources of As, including point and diffuse sources, various inorganic and organic As species, and their toxicity in the environment. Moreover, the fate of As in the environment, economic implications of As-contaminated food and food products, and the bioavailability and bio-accessibility of As in environmental media are also briefly summarized. Remediation technologies for As-contaminated soil with the latest case study and regulatory limits of As in soil are also presented in this chapter. Overall, this chapter incorporates the past and contemporary knowledge of As, which will be useful for better management of As in the near future.

DOI 10.1016/B978-0-323-90400-1.00011-2
Co-authors Mahmud Rahman
2022 Paul SK, Naidu R, 'Layered aluminosilicate nanoskeletons: The structure and properties of nanoherbicide formulations', Advances in Agronomy, Elsevier, Amsterdam, Netherlands 301-345 (2022) [B1]
DOI 10.1016/bs.agron.2022.04.003
Citations Scopus - 2
2021 Cheng Y, Yang RMH, Alejandro FM, Li F, Balavandy SK, Wang L, et al., 'Current applications of colourimetric microfluidic devices (smart phone based) for soil nutrient determination', Smartphone-Based Detection Devices, Elsevier, Amsterdam, Netherlands 103-128 (2021) [B1]
DOI 10.1016/B978-0-12-823696-3.00010-6
Citations Scopus - 4
Co-authors Ying Cheng, Liang Wang
2021 Manna MC, Rahman MM, Naidu R, Bari ASMF, Singh AB, Thakur JK, et al., 'Organic farming: A prospect for food, environment and livelihood security in Indian agriculture', Advances in Agronomy, Elsevier, Netherlands, Amsterdam 101-153 (2021) [B1]
DOI 10.1016/bs.agron.2021.06.003
Citations Scopus - 13Web of Science - 4
Co-authors Mahmud Rahman
2020 Wijayawardena MAA, Liu Y, Yan K, Duan L, Umeh AC, Naidu R, Semple KT, 'Assessment of the Oral Bioavailability of Organic Contaminants in Humans', Handbook of Environmental Chemistry 191-218 (2020) [B1]

Bioavailability estimates the actual internal uptake or absorption of contaminants that enter the body (internal dose) and helps in providing a more accurate estimation of the hum... [more]

Bioavailability estimates the actual internal uptake or absorption of contaminants that enter the body (internal dose) and helps in providing a more accurate estimation of the human risks than the usage of total concentration. This is important for exposure assessment for children in relation to their hand-to-mouth activities. For example significant reductions of the bioavailability of long-term contaminated soils have been demonstrated using various animal models. The measurement for bioavailability involves various uncertainties for organic contaminants. It is crucial to determine the parameters that influence the results of bioavailability. This chapter provides a summary of the current state of knowledge for the determination of bioavailability for a range of organic contaminants. The information provided will be useful in facilitating further research efforts for the investigation of bioavailability of contaminants in conducting exposure assessments.

DOI 10.1007/698_2020_596
Co-authors Ayanka Wijayawardena, Anthony Umeh, Yanju Liu
2020 Umeh AC, Naidu R, Owojori OJ, Semple KT, 'Bioavailability and Bioaccessibility of Hydrophobic Organic Contaminants in Soil and Associated Desorption-Based Measurements', Bioavailability of Organic Chemicals in Soil and Sediment, Springer Nature, Switzerland 293-350 (2020) [B1]
DOI 10.1007/698_2020_521
Citations Scopus - 8
Co-authors Anthony Umeh
2019 Rahman MM, Naidu R, 'Potential Exposure to Arsenic and Other Elements from Rice in Bangladesh: Health Risk Index', Arsenic in Drinking Water and Food 333-340 (2019)

This study evaluates the potential exposure to arsenic (As) and other elements in rice from two severely arsenic (As)-impacted districts (Comilla and Chandpur) of Bangladesh. Rice... [more]

This study evaluates the potential exposure to arsenic (As) and other elements in rice from two severely arsenic (As)-impacted districts (Comilla and Chandpur) of Bangladesh. Rice samples were collected from 99 households and analyzed for this purpose. The mean concentrations of As, Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn in rice were 187 µg/kg, 40 µg/kg, 16 µg/kg, 819 µg/kg, 1.8 mg/kg, 7.3 mg/kg, 549 µg/kg, 61 µg/kg, and 8.9 mg/kg, respectively. Food and drinking water contribute 20.2, 0.27, 0.24, 6.9, 20, 100, 5.3, 1.6 and 100 µg of As, Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn per kg bw daily, respectively. Drinking water contributes 92% of the total dietary intake of As to adults whereas food contributes 90-100% for other elements. The estimated health risk index (HRI) for As, Cd, Cr, Cu, Pb, Mn, Ni, and Zn are 67.4, 0.27, 2.3, 0.54, 0.41, 0.73, 0.27, and 0.33, respectively. The results show that As and Cr in food and drinking water pose significant health risks to the study population as the values of HRIs were greater than 1.

DOI 10.1007/978-981-13-8587-2_12
Citations Scopus - 9
Co-authors Mahmud Rahman
2019 Nuruzzaman M, Liu Y, Rahman MM, Dharmarajan R, Duan L, Uddin AFMJ, Naidu R, 'Nano-biopesticide: Composition and preparation methods', Nano-biopesticides Today and Future Perspectives, Elsevier, Cambridge, MA 69-131 (2019) [B1]
Citations Scopus - 27
Co-authors Mahmud Rahman, Md Nuruzzaman, Yanju Liu
2018 Kunhikrishnan A, Park JH, Bolan SS, Naidu R, Bolan N, 'Phosphorus-induced (im)mobilization of heavy metal(loid)s in soil', Phosphate in Soils: Interaction with Micronutrients, Radionuclides and Heavy Metals, CRC Press, Boca Raton 1-38 (2018)
Co-authors Nanthi Bolan
2018 Liu Y, Li Y, Bekele D, Naidu R, 'The environmental evaluation of applying red mud as soil amendment a review', Soil amendments for sustainability challenges and perspectives, CRC Press Taylor & Francis Group, Boca Raton FL, USA 221-233 (2018)
Co-authors Yanju Liu, Dawit Bekele
2018 Chandra Manna M, Rahman MM, Naidu R, Sahu A, Bhattacharjya S, Wanjari RH, et al., 'Bio-Waste Management in Subtropical Soils of India: Future Challenges and Opportunities in Agriculture', Advances in Agronomy, Elsevier, Amsterdam, Netherlands 87-148 (2018) [B1]
DOI 10.1016/bs.agron.2018.07.002
Citations Scopus - 27Web of Science - 14
Co-authors Mahmud Rahman
2017 Bolan N, 'Spoil to Soil: Mine Site Rehabilitation and Revegetation 1st Edition by N.S. Bolan (Editor), M.B. Kirkham (Editor), Y.S. Ok (Editor)', , CRC Press, USA USA-USA (2017)
Citations Scopus - 10
Co-authors Girish Choppala, Nanthi Bolan
2017 Rahman M, Naidu R, 'Arsenic: Southeast Asia', Encyclopedia of Soil Science, Third Edition, CRC Press, Boca Raton, FL 161-167 (2017)
DOI 10.1081/E-ESS3-120053532
Co-authors Mahmud Rahman
2017 Basak BB, Sarkar B, Biswas DR, Sarkar S, Sanderson P, Naidu R, 'Bio-Intervention of Naturally Occurring Silicate Minerals for Alternative Source of Potassium: Challenges and Opportunities', Advances in Agronomy, Elsevier, Cambridge, MA 115-145 (2017) [B1]
DOI 10.1016/bs.agron.2016.10.016
Citations Scopus - 55Web of Science - 36
2017 Lamb D, Sanderson P, Wang L, Kader M, Naidu R, 'Phytocapping of mine waste at derelict mine sites in New South Wales', Spoil to Soil: Mine Site Rehabilitation and Revegetation, CRC PRESS, Boca Raton 215-240 (2017)
Co-authors Liang Wang, Nanthi Bolan
2017 Gurung SR, Wijesekara H, Seshadri B, Stewart RB, Gregg PEH, Bolan NS, 'Sources and management of acid mine drainage', Spoil to Soil: Mine Site Rehabilitation and Revegetation 33-56 (2017)

Acid mine drainage (AMD) from both active and abandoned mine sites is a major environmental issue for the mining industry in environmentally concerned regions of the world (Gray 1... [more]

Acid mine drainage (AMD) from both active and abandoned mine sites is a major environmental issue for the mining industry in environmentally concerned regions of the world (Gray 1997, Lindsay et al. 2015). The term is used to describe any seepage, leachate, or drainage affected by the oxidation products of sulfide minerals in mine sites when exposed to air and water (Figure 3.1). Both chemical reactions and biological transformations are recognized as being responsible for generating AMD (Lindsay et al. 2015). AMD is typically characterized by low pH and high levels of dissolved metal salts, as well as high concentrations of acidity, sulfate, iron, and other metals (Gray 1997). Once the AMD process begins, it is difficult to control, often accelerates, and is likely to persist for decades or centuries. In the absence of natural or added neutralizing materials 34(carbonate minerals such as calcite or dolomite), the AMD is likely to contain toxic levels of heavy metals such as Fe, Al, Mn, Cu, Pb, Zn, and Cd, which can cause serious environmental problems in soil and water systems (Sengupta 1994)

DOI 10.1201/9781351247337
Citations Scopus - 1
Co-authors Nanthi Bolan
2017 Murdoch D, Karunanithi R, 'Profitable beef cattle production on rehabilitated mine lands', Spoil to Soil: Mine Site Rehabilitation and Revegetation 111-122 (2017)

The Australian beef cattle industry is one of the most efficient and ranks third largest in beef export in the world, contributing 4% of beef supply. As on 2013, the meat value pr... [more]

The Australian beef cattle industry is one of the most efficient and ranks third largest in beef export in the world, contributing 4% of beef supply. As on 2013, the meat value produced from beef cattle, in Australia is estimated to be $12.3 billion (Fastfacts, 2013). Beef cattle production ranges from intensive farms on fertile lands to extensive range lands. With the increase in human population and increase in affordability of meat-based food, the demand for beef cattle is also increasing

DOI 10.1201/9781351247337
Citations Scopus - 1
Co-authors Nanthi Bolan
2017 Wijesekara H, Bolan NS, Colyvas K, Seshadri B, Ok YS, Awad YM, et al., 'Use of biowaste for mine site rehabilitation: A meta-analysis on soil carbon dynamics', Spoil to Soil: Mine Site Rehabilitation and Revegetation 59-74 (2017)

¿Mining¿ refers to the excavation of economically important resources from terrestrial landmasses, thereby generating a large quantity of valuable precursors for commercial and in... [more]

¿Mining¿ refers to the excavation of economically important resources from terrestrial landmasses, thereby generating a large quantity of valuable precursors for commercial and industrial activities. Mineral products such as coal, aluminum, copper, iron, gold, and mineral sand are examples from the mining industry. Though mining advances global economic prosperity, this industry severely disturbs the land, water resources, and the environment (Figure 4.1). Mined waste materials such as tailings, subsoils, oxidized wastes, and fireclay are the main causes for land disturbance. Presence of potentially hazardous substances such as heavy metals in elevated concentrations in the mined waste materials has caused land contamination. Poor soil characteristics such as low-level organic matter and poor soil texture and structure have resulted in deterioration of the land, adversely affecting the establishment of plants and soil microbial flora and fauna (Boyer et al. 2011, Johnson 2003, Larney and Angers 2012, Sopper 1992). Disturbed mine sites are known to contaminate water resources 60 61in many countries, mainly from acid mine drainage (Bolan et al. 2003, Lindsay et al. 2015, Taylor et al. 1997). Therefore, these sites need to be rehabilitated to minimize potential environmental consequences, thereby enhancing their utilization. Revegetation of mine sites is one of the potential strategies that can be applied to improve these disturbed land masses. Here, infertile soil properties are improved by a series of processes such as land application of biowastes

DOI 10.1201/9781351247337
Citations Scopus - 3
Co-authors Nanthi Bolan, Kim Colyvas
2017 Thangavel R, Karunanithi R, Wijesekara H, Yan Y, Seshadri B, Bolan NS, 'Phytotechnologies for mine site rehabilitation', Spoil to Soil: Mine Site Rehabilitation and Revegetation 203-214 (2017)

Soils are a prime and very important natural resource, and soil fertility is a major concern for sustainable agriculture and economic development of any country. In recent decades... [more]

Soils are a prime and very important natural resource, and soil fertility is a major concern for sustainable agriculture and economic development of any country. In recent decades, problems of contaminated land sites, water bodies, groundwater, and air worldwide have increased manyfold due to anthropogenic activities. Mining is one of the anthropogenic activities that cause pollution problems in, around, and outside of mining areas. It results in the mobilization of metals and organic and inorganic substances into the environment, which causes pollution of air, soils, sediments, vegetation, and surface and groundwater. It also increases the morbidity and mortality of plant and animal species and results in the loss of visual, aesthetic characteristics of landscapes (Bolan et al. 2003; Pavli et al. 2015)

DOI 10.1201/9781351247337
Citations Scopus - 1
Co-authors Nanthi Bolan
2017 Sarkar B, Wijesekara H, Mandal S, Singh M, Bolan NS, 'Characterization and improvement in physical, chemical, and biological properties of mine wastes', Spoil to Soil: Mine Site Rehabilitation and Revegetation 3-16 (2017)

Degradation of land resources as a result of mining activities poses serious threat to the environment. It has been estimated that around 0.4 × 106 km2 area of land is impacted by... [more]

Degradation of land resources as a result of mining activities poses serious threat to the environment. It has been estimated that around 0.4 × 106 km2 area of land is impacted by mining activities around the world (Hooke and Martín-Duque 2012). Unfortunately, a significant percentage of this area has never been reclaimed, which poses health risks to ecosystems and humans. Often, these wastes contain hazardous substances such as heavy metals, organic contaminants, radionuclides, and crushed limestone, where the latter could become a potential source of atmospheric CO2 emission. Thus, they not only pose serious risk to the groundwater and surface water, but also to the atmosphere (Wijesekara et al. 2016). In order to tackle the issues related to mine wastes and manage the affected sites sustainably, an appropriate physical, chemical, and biological characterization of waste materials becomes very prudent. Due to the lack of both above- and below-ground biodiversity, mine waste sites are very poor in organic matter content. This in return leads to poor seed germination, plant growth, and vegetation establishment. In many cases, the associated toxic contaminants also seriously compromise the soil health, microbial life, and plant growth (Castillejo and Castelló 2010, Larney and Angers 2012). This chapter describes the physicochemical characteristics of mine wastes, including spoil, tailings, and overburden, by underpinning their source-property relationships. The value of readily available biowaste resources, including biosolids, composts, and manures, in improving such physicochemical properties of mining-impacted soils/sites is also discussed

DOI 10.1201/9781351247337
Citations Scopus - 4
Co-authors Nanthi Bolan
2017 Lamb D, Sanderson P, Wang L, Kader M, Naidu R, 'Phytocapping of mine waste at derelict mine sites in New South Wales', Spoil to Soil: Mine Site Rehabilitation and Revegetation 215s-240s (2017)

Historically, mining of metalliferous ore bodies was a relatively dispersed activity, with numerous small mines occurring throughout many western countries including the United St... [more]

Historically, mining of metalliferous ore bodies was a relatively dispersed activity, with numerous small mines occurring throughout many western countries including the United States, the United Kingdom, and Australia (Soucek et al. 2000, Grant et al. 2002, Mayes et al. 2009). Many metalliferous mine sites began operation in the late eighteenth and early nineteenth centuries and were abandoned in most instances before the environmental movement in Western countries. As such, there was very little recognition of the potential impacts caused by the dispersal of metal toxicants such as arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) into the surrounding environments from these sites. Many of these contaminants are cariogenic in humans (e.g., As), cause a range of human health-related impacts (Pb, Cd), and are toxic to ecological receptors in nearby streams and surrounding terrestrial environments (Cu, Zn, Mn, Ni). As a result of the lack of regard for potential impacts, much of the mining waste was discarded carelessly throughout mining sites, and in some cases, directly into nearby watercourses

DOI 10.1201/9781351247337
Citations Scopus - 6
Co-authors Liang Wang, Nanthi Bolan
2017 Adhikari T, Dharmarajan R, 'Nanoscale materials for mine site remediation', Spoil to Soil: Mine Site Rehabilitation and Revegetation 95-108 (2017)

In the era of global competition, mineral exploitation has been significantly increased resulting in pressure on the environment in the form of massive deforestation, soil polluti... [more]

In the era of global competition, mineral exploitation has been significantly increased resulting in pressure on the environment in the form of massive deforestation, soil pollution, and erosion. Despite global economic importance, mineral industries have adversely affected the ecosystems across the world. The impact of mine waste in soil depends on its type and composition, commodity being mined, type of ore, and technologies used to process the ore. Mining types and activities are several, which include surface mining, underground mining, openpit mining, in situ mining, pillar mining, slope mining, block caving, and quarrying. And thus mine waste materials vary in their physical and chemical composition and potential for soil contamination. The different 96types of mine waste materials are overburden, waste rock, tailings, slags, mine water, sludge, and gaseous wastes. Overburden includes the soil and rock that are removed to gain access to the ore deposits at openpit mines. It is usually dumped on the surface at mine sites where it will not hinder further expansion of the mining operation. Waste rock contains minerals in concentrations considered too low to be extracted at a profit. It is often stored in heaps on the mine site. Tailings are finely ground rock and mineral waste products of mineral processing operations. They also contain leftover processing chemicals, and usually are deposited in the form of water-based slurry into tailings ponds. Slags are nonmetallic by-products from metal smelting. Mine water is produced in a number of ways at mine sites and varies in its quality and potential for environmental contamination. Sludge is produced at active water treatment plants used at some mine sites and consists of the solids that have been removed from the water as well as any chemicals. Gaseous wastes are produced during high-temperature chemical processing such as smelting, and consist of particulate matter and oxides of sulfur

DOI 10.1201/9781351247337
Co-authors Nanthi Bolan
2016 Wijayawardena A, Mallavarapu M, Naidu R, 'Exposure, toxicity, health impacts, and bioavailability of heavy metal mixtures', Advances in Agronomy, Elsevier, London 175-234 (2016) [B1]
DOI 10.1016/bs.agron.2016.03.002
Citations Scopus - 46Web of Science - 29
Co-authors Ayanka Wijayawardena, Megh Mallavarapu
2016 Kuppusamy S, Palanisami T, Megharaj M, Venkateswarlu K, Naidu R, 'Ex-situ remediation technologies for environmental pollutants: A critical perspective', Reviews of Environmental Contamination and Toxicology, Springer International, Cham, Switzerland 117-192 (2016) [B1]
DOI 10.1007/978-3-319-20013-2_2
Citations Scopus - 134Web of Science - 98
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Kuppusamy S, Palanisami T, Megharaj M, Venkateswarlu K, Naidu R, 'In-situ remediation approaches for the management of contaminated sites: A comprehensive overview', Reviews of Environmental Contamination and Toxicology, Springer International, Cham, Switzerland 1-115 (2016) [B1]
DOI 10.1007/978-3-319-20013-2_1
Citations Scopus - 174Web of Science - 108
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Seshadri B, Bolan NS, Thangarajan R, Jena U, Das KC, Wang H, Naidu R, 'Biomass energy from revegetation of landfill sites', Bioremediation and Bioeconomy 99-109 (2016)

While landfilling provides a simple and economic means of waste disposal, it causes environmental impacts including leachate generation and greenhouse gas emissions. Increasingly,... [more]

While landfilling provides a simple and economic means of waste disposal, it causes environmental impacts including leachate generation and greenhouse gas emissions. Increasingly, revegetation is practiced on traditionally managed landfill sites to mitigate environmental degradation. It also provides a source of biomass for energy production. Biomass from landfill sites can be converted to bioenergy through biochemical and thermochemical processes. Selection of suitable biomass-producing plants (high-yielding crops), pretreatments (e.g., removal of lignin) and providing ideal conditions for the conversion processes (e.g., temperature and pressure) influence the quantity and quality of energy generated. This chapter provides an overview of the potential volumes of biomass produced from landfills and the various methods of biomass energy conversion.

DOI 10.1016/B978-0-12-802830-8.00005-8
Citations Scopus - 11
Co-authors Nanthi Bolan
2016 Mandal S, Kunhikrishnan A, Bolan NS, Wijesekara H, Naidu R, 'Application of Biochar Produced From Biowaste Materials for Environmental Protection and Sustainable Agriculture Production', Environmental Materials and Waste: Resource Recovery and Pollution Prevention, Academic Press, London 73-89 (2016) [B1]
DOI 10.1016/B978-0-12-803837-6.00004-4
Citations Scopus - 28
Co-authors Nanthi Bolan
2016 Karunanithi R, Szogi A, Bolan NS, Naidu R, Ok YS, Krishnamurthy S, Seshadri B, 'Phosphorus Recovery From Wastes', Environmental Materials and Waste: Resource Recovery and Pollution Prevention, Elsevier, Amsterdam, Netherlands 687-705 (2016)
DOI 10.1016/B978-0-12-803837-6.00027-5
Citations Scopus - 17
Co-authors Nanthi Bolan
2015 Karunanithi R, Szogi AA, Bolan N, Naidu R, Loganathan P, Hunt PG, et al., 'Phosphorus recovery and reuse from waste streams', Advances in agronomy, Academic Press, Maryland Heights, MO 173-250 (2015) [B1]
DOI 10.1016/bs.agron.2014.12.005
Citations Scopus - 98Web of Science - 85
Co-authors Nanthi Bolan
2015 Bolan NS, Adriano DC, Naidu R, De La Luz Mora M, Santiagio M, 'Phosphorus-trace element interactions in soil-plant systems', Phosphorus: Agriculture and the Environment 317-352 (2015)

Phosphorus (P) reaches soils through both pedogenic and anthropogenic sources. This chapter provides a brief overview of the major sources and the dynamics of common P compounds a... [more]

Phosphorus (P) reaches soils through both pedogenic and anthropogenic sources. This chapter provides a brief overview of the major sources and the dynamics of common P compounds and trace elements in soils and describes processes by which these P compounds act as a source for the mobilization and as a sink for the immobilization of trace elements. As land treatment becomes an important waste management practice, soil is increasingly being seen as a major source of trace elements reaching the food chain, mainly through plant uptake and animal transfer. The chapter discusses the practical implications of P-trace element interactions in relation to the potential value of P compounds in the natural remediation of trace element-contaminated soils. P-induced zinc deficiency is probably the most widely examined P-trace element interaction in the soil-plant system.

DOI 10.2134/agronmonogr46.c10
Citations Scopus - 13
Co-authors Nanthi Bolan
2015 Sarkar B, Naidu R, 'Organopalygorskites prepared from quaternary ammonium compounds and their environmental uses', Natural Mineral Nanotubes Properties and Applications 323-340 (2015)

Clay minerals are abundant in nature and have many industrial uses, such as in the ceramics, cement, paper, cosmetics, print, and drug industries. Clays are also extensively used ... [more]

Clay minerals are abundant in nature and have many industrial uses, such as in the ceramics, cement, paper, cosmetics, print, and drug industries. Clays are also extensively used in environmental remediation due to unique properties, such as high surface area, strong chemical stability, non-toxic nature, and the adsorptive and ion exchange properties (Churchman et al., 2006). Clays are generally produced by mining but can be increased in value by surface modification. Naturally occurring clay minerals are intrinsically hydrophilic in nature. As a result, clays have a good affinity for ionic contaminants, such as heavy metal cations, but do not significantly interact with hydrophobic organic contaminants. Clay minerals¿ surface modification with organic compounds, such as quaternary ammonium compounds (QACs) can produce modified clays with a high affinity for organic contaminants. Modified clay minerals thus prepared are known as organoclays (Boyd et al., 1988; Jordan and Williams, 1954; Sarkar et al., 2012c; Xi et al., 2005b). Depending on the type of organic compounds used for modification, organoclays can act as the adsorption sink for both hydrophobic organic contaminants and ionic metals and metalloids (Sarkar et al., 2012a, b, c).

DOI 10.1201/b18107
Citations Scopus - 3
2015 Sarkar B, Naidu R, 'Nutrient and Water Use Efficiency in Soil: The Influence of Geological Mineral Amendments', Nutrient Use Efficiency: From Basics to Advance, Springer, New Delhi, India 29-44 (2015)
DOI 10.1007/978-81-322-2169-2_3
Citations Scopus - 14
2015 Matheyarasu R, Seshadri B, Bolan N, Naidu R, 'Impacts of Abattoir Waste-Water Irrigation on Soil Fertility and Productivity', Irrigation and Drainage - Sustainable Strategies and Systems, InTech, Rijeka, Croatia 55-75 (2015)
DOI 10.5772/59312
Co-authors Nanthi Bolan
2014 Megharaj M, Venkateswarlu K, Naidu R, 'Bioremediation', Encyclopedia of Toxicology: Third Edition 485-489 (2014)

Anthropogenic activities linked to industrialization and modern agriculture have led to the production and release of several chemicals into the environment resulting in contamina... [more]

Anthropogenic activities linked to industrialization and modern agriculture have led to the production and release of several chemicals into the environment resulting in contamination of soil, water, and air, and posing risk to human and ecological health. Bioremediation is emerging as a safe and economical alternative to costly and disruptive physicochemical remediation techniques. This article provides a brief overview of various bioremediation technologies, their applicability, and their limitations.

DOI 10.1016/B978-0-12-386454-3.01001-0
Citations Scopus - 28
Co-authors Megh Mallavarapu
2014 Naidu R, Bekele D, Birke V, 'Permeable Reactive Barriers: Cost-Effective and Sustainable Remediation of Groundwater', Permeable Reactive Barriers: Sustainable Groundwater Remediation, CRC Press, Boca Raton, FL 1-24 (2014)
Citations Scopus - 2
Co-authors Dawit Bekele, Sreenivasulu Chadalavada
2014 Bekele D, Ravi N, Volker B, Sreenivasulu C, 'Choosing the Best Design and Construction Technologies for Permeable Reactive Barriers', Permeable Reactive Barrier: Sustainable Groundwater Remediation, CRC Press, Boca Raton, FL 41-62 (2014)
Citations Scopus - 2
Co-authors Sreenivasulu Chadalavada, Dawit Bekele
2014 Chadalavada S, Wegner M, Naidu R, 'Groundwater modeling involving PRBs: General aspects, case study', Permeable Reactive Barrier: Sustainable Groundwater Remediation 63-85 (2014)

Permeable reactive barrier (PRB) technology is an increasingly viable option for remediating chlorinated hydrocarbon, petroleum hydrocarbon, and dissolved heavy metals contaminati... [more]

Permeable reactive barrier (PRB) technology is an increasingly viable option for remediating chlorinated hydrocarbon, petroleum hydrocarbon, and dissolved heavy metals contamination (Chapters 2 and 3). The PRB is an in situ passive remediation technology and has certain advantages compared to other active remediation technologies such as the pump-and-treat and chemical oxidation. This technology also prevents the contamination from migrating to uncontaminated aquifer systems. About 200 PRBs have been installed worldwide (Das, 2002; ETI, 2005, see Chapter 3) for treating common contaminants like chlorinated hydrocarbons (Burris et al., 1995; Orth and Gillham, 1996; Roberts et al., 1996; McMahon et al., 1999; Vogan et al., 1999; Schlicker et al., 2000), petroleum hydrocarbons (Guerin et al., 2002) and heavy metals (Powell et al., 1995; Gu et al., 1998; Shokes and Möller, 1999). A schematic diagram demonstrating the PRB technology is shown in Figure 4.1. The most important components of the design and implementation of the PRB are a detailed understanding of the subsurface hydrogeology, the kinetics of the reactive material chosen for the barrier, and the long-term monitoring plan. The kinetics of the different reactive materials is well understood and documented. While a number of different reactive materials have been used, most of the PRBs installed worldwide utilize zerovalant iron (ZVI) as the reactive material (Rabideau et al., 2005). An overview of hydrogeological modeling for PRBs is given in Gupta and Fox (1999). The most challenging component of PRB design and implementation is the site hydraulics, and several case studies of PRBs demonstrate this aspect of the technology.

Citations Scopus - 1
Co-authors Sreenivasulu Chadalavada
2014 Rahman MA, Rahman MM, Naidu R, 'Arsenic in Rice: Sources and Human Health Risk', Wheat and Rice in Disease Prevention and Health, Elsevier, Amsterdam, Netheralnds 365-375 (2014)
DOI 10.1016/B978-0-12-401716-0.00028-3
Citations Scopus - 12
Co-authors Mahmud Rahman
2014 Naidu R, Bekele D, Birke V, 'Permeable Reactive Barriers: Cost-Effective and Sustainable Remediation of Groundwater', Permeable Reactive Barriers: Sustainable Groundwater Remediation, CRC Press, Boca Raton, FL 1-24 (2014)
Citations Scopus - 2
Co-authors Dawit Bekele, Sreenivasulu Chadalavada
2014 Bekele D, Ravi N, Volker B, Sreenivasulu C, 'Choosing the Best Design and Construction Technologies for Permeable Reactive Barriers', Permeable Reactive Barrier: Sustainable Groundwater Remediation, CRC Press, Boca Raton, FL 41-62 (2014)
Citations Scopus - 2
Co-authors Sreenivasulu Chadalavada, Dawit Bekele
2012 Thavamani P, Megharaj M, Venkateswarlu K, Naidu R, 'Mixed contamination of polyaromatic hydrocarbons and metals at manufactured gas plant sites: toxicity and implications to bioremediation', Environmental contamination health risks, bioavailability and bioremediation, Taylor and Francis, New York 347-367 (2012)
Citations Scopus - 8
Co-authors Thava Palanisami, Megh Mallavarapu
2012 'Decision-Making Support Tools for Managing Electronic Waste ..... Peeranart Kiddee, Ravi Naidu, and Ming Hung Wong', Environmental Contamination, CRC Press 230-251 (2012)
DOI 10.1201/b12531-15
2012 Thangarajan R, Kunhikrishnan A, Seshadri B, Bolan NS, Naidu R, 'Greenhouse gas emission from wastewater irrigated soils', 225-236 (2012)

With increasing demand for world water supply, wastewater reuse is a great opportunity to meet the water need, especially for agricultural and industrial development. Wastewater o... [more]

With increasing demand for world water supply, wastewater reuse is a great opportunity to meet the water need, especially for agricultural and industrial development. Wastewater originates from many sources and hence its composition differs from origin and treatment processes. Wastewater rich in organic matter acts as a soil conditioner, thereby enhancing soil health. Wastewater also acts as a source of nutrient input in agriculture which in turn can reduce, or even eliminate the need for commercial fertilisers. However, wastewater usage in agriculture poses several threats like eutrophication, salinity, toxic chemicals (heavy metal(loids), pesticides), pathogen contamination, and most notably, nutrient leaching, and greenhouse gas (GHG) emission. These threats affect public health, soil and ground water resources, environment, crop quality, ecological, and property values. Biological degradation of the organic matter present in wastewater is considered one of the anthropogenic sources of major GHGs (carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4). In this paper, an overview of various sources of wastewater, effects of wastewater application on GHG emission from soil, and the strategies to mitigate wastewater-induced GHG emission from soils is presented. © 2012 WIT Press.

DOI 10.2495/SI120191
Citations Scopus - 7
Co-authors Nanthi Bolan
2012 Wong MH, Leung AOW, Wu S, Leung CKM, Naidu R, 'Mitigating Environmental and Health Risks Associated with Uncontrolled Recycling of Electronic Waste: Are International and National Regulations Effective?', Environmental Contamination: Health Risks and Ecological Restoration 193-208 (2012)
DOI 10.1201/b12531-14
Citations Scopus - 4
2012 Kiddee P, Naidu R, Wong MH, 'Decision-Making Support Tools for Managing Electronic Waste', Environmental Contamination: Health Risks and Ecological Restoration 209-228 (2012)

There are a number of definitions of electronic wastes (or e-waste), which is also known as waste electrical and electronic equipment (WEEE) (EU 2002; Puckett and Smith 2002; Elec... [more]

There are a number of definitions of electronic wastes (or e-waste), which is also known as waste electrical and electronic equipment (WEEE) (EU 2002; Puckett and Smith 2002; Electronic Recyclers International 2006; Wong et al. 2007a). For the purpose of this chapter, e-waste will be defined as consisting of old, end-of-life electronic devices such as televisions, refrigerators, washing machines, vacuum cleaners, computers, computer peripherals, and mobile phones that original users no longer want because they are obsolete or irreparable.

DOI 10.1201/b12531-15
2011 Thangavadivel K, Megharaj M, Mudhoo A, Naidu R, 'Degradation of organic pollutants using ultrasound', Handbook on Applications of Ultrasound: Sonochemistry for Sustainability 447-474 (2011)

Most organic pollutants are hydrocarbon based and when these are halogenated they become more persistent in the environment and more hazardous to humans and other living organisms... [more]

Most organic pollutants are hydrocarbon based and when these are halogenated they become more persistent in the environment and more hazardous to humans and other living organisms (Andrea et al., 2001). During degradation, hydrocarbon pollutants are broken down into simpler molecules such as short-chain organic acids or carbon dioxide and water and/or inorganic ions (Adewuyi, 2001). Today, organic pollutants are generally remediated using biological, chemical, physical, and physicochemical process or a combination of these (Andrea et al., 2001).

Citations Scopus - 17
Co-authors Megh Mallavarapu
2011 Bolan N, Brennan R, Budianta D, Camberato J, Naidu R, Pan W, et al., 'Bioavailability of N, P, K, Ca, Mg, S, Si, and Micronutrients', Handbook of Soil Sciences: Resource Management and Environmental Impacts, CRC Press, Boca Raton, FL 1-80 (2011)
Co-authors Nanthi Bolan
2011 Bolan NS, Park JH, Robinson B, Naidu R, Huh KY, 'PHYTOSTABILIZATION: A GREEN APPROACH TO CONTAMINANT CONTAINMENT', ADVANCES IN AGRONOMY, VOL 112, ELSEVIER ACADEMIC PRESS INC 145-204 (2011)
DOI 10.1016/B978-0-12-385538-1.00004-4
Citations Scopus - 272Web of Science - 167
Co-authors Nanthi Bolan
2010 Caceres T, Megharaj M, Venkateswarlu K, Sethunathan N, Naidu R, 'Fenamiphos and Related Organophosphorus Pesticides: Environmental Fate and Toxicology', REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, VOL 205, SPRINGER 117-162 (2010)
DOI 10.1007/978-1-4419-5623-1_3
Citations Scopus - 44Web of Science - 32
Co-authors Megh Mallavarapu
2010 Kopittke PM, Lombi E, Menzies NW, Naidu R, 'Principles of plant-based remediation of contaminated soils', Industrial Crops and Uses 446-469 (2010)
Citations Scopus - 5
2009 Haynes RJ, Murtaza G, Naidu R, 'INORGANIC AND ORGANIC CONSTITUENTS AND CONTAMINANTS OF BIOSOLIDS: IMPLICATIONS FOR LAND APPLICATION', ADVANCES IN AGRONOMY, VOL 104, ELSEVIER ACADEMIC PRESS INC 165-267 (2009)
DOI 10.1016/S0065-2113(09)04004-8
Citations Scopus - 120Web of Science - 90
2008 Naidu R, Bolan NS, 'Chapter 2 Contaminant chemistry in soils: Key concepts and bioavailability', 9-37 (2008)
DOI 10.1016/S0166-2481(07)32002-3
Citations Scopus - 38
Co-authors Nanthi Bolan
2008 Naidu R, Pollard SJT, Bolan NS, Owens G, Pruszinski AW, 'Chapter 4 Bioavailability: The underlying basis for risk-based land management', 53-72 (2008)
DOI 10.1016/S0166-2481(07)32004-7
Citations Scopus - 27
Co-authors Nanthi Bolan
2008 Naidu R, Semple KT, Megharaj M, Juhasz AL, Bolan NS, Gupta SK, et al., 'Chapter 3 Bioavailability: Definition, assessment and implications for risk assessment', 39-51 (2008)
DOI 10.1016/S0166-2481(07)32003-5
Citations Scopus - 57
Co-authors Megh Mallavarapu, Nanthi Bolan
2008 Bolan NS, Ko BG, Anderson CWN, Vogeler I, Mahimairaja S, Naidu R, 'Chapter 27 Manipulating bioavailability to manage remediation of metal-contaminated soils', 657-678 (2008)
DOI 10.1016/S0166-2481(07)32027-8
Citations Scopus - 11
Co-authors Nanthi Bolan
2008 Fuentes B, de la Luz Mora M, Bolan NS, Naidu R, 'Chapter 16 Assessment of phosphorus bioavailability from organic wastes in soil', 363-411 (2008)
DOI 10.1016/S0166-2481(07)32016-3
Citations Scopus - 16
Co-authors Nanthi Bolan
2008 Bhattacharya P, Von Bromssen M, Aziz Hasan M, Jacks G, Matin Ahmed K, Sracek O, et al., 'Arsenic mobilisation in the holocene flood plains in south-central Bangladesh: Evidences from the hydrogeochemical trends and modeling results', Groundwater for Sustainable Development: Problems, Perspectives and Challenges 283-299 (2008)

This study presents the results of the investigation of arsenic (As) enrichment in groundwater of three alluvial aquifers at the Bengal Delta Plain (BDP) in Sonargaon in Narayanga... [more]

This study presents the results of the investigation of arsenic (As) enrichment in groundwater of three alluvial aquifers at the Bengal Delta Plain (BDP) in Sonargaon in Narayanganj, Chandina in Comilla, and Sirajdikhan in Munshiganj districts in South-central Bangladesh. Water samples were collected from these sites from wells with screens placed at different depths and the hydrogeochemical characteristics and redox status were determined. The highest DOC and HCO-3 concentrations were found at Sirajdikhan site and lower concentrations at Sonargaon and Chandina sites. In contrast, the highestNH+ 4 concentrationswere found at Chandina site and concentrations at other sites were much lower. The correlation between dissolved As and Fe was high at Sirajdikhan and Sonargaon sites, but not at Chandina site. Also, at Chandina site dissolved Mn concentrations were low, suggesting that Mn(IV) redox buffering step was missing. Speciation modeling indicated a possibility of siderite precipitation at all sites, but precipitation of rhodochrosite only at Sonargaon and Sirajdikhan sites. Calculated log PCO2 were very high (reaching -1.37 at Sirajdikhan site), suggesting production of CO2 in redox processes. The hydrogeochemical trends and modeling results suggest that dissolved As may be de-coupled from dissolved Mn, when Mn(IV) content in solid phase is low (or when released As is re-adsorbed) and from dissolved Fe (when precipitation of Fe(II) minerals controls Fe concentrations). Furthermore, several redox processes may operate simultaneously, depending on kinetic constraints and refractoriness of Fe(III) minerals.

Citations Scopus - 3
2008 Naidu R, Bolan NS, Megharaj M, Juhasz AL, Gupta SK, Clothier BE, Schulin R, 'Chapter 1 Chemical bioavailability in terrestrial environments', 1-6 (2008)
DOI 10.1016/S0166-2481(07)32001-1
Citations Scopus - 38
Co-authors Nanthi Bolan, Megh Mallavarapu
2008 Singh J, Saggar S, Bolan N, Zaman M, 'The Role of inhibitors in the bioavailability and mitigation of nitrogen losses in grassland ecosystems', Chemical Bioavailability in Terrestrial Environments, Elsevier Science Limited, Amsterdam 329-362 (2008)
Co-authors Nanthi Bolan
2008 Bolan N, Rowarth J, de la Luz Mora M, Adriano D, Curtin D, 'Biological transformation and bioavailability of nutrient elements in acid soils as affected by liming', Chemical Bioavailability in Terrestrial Environments, Elsevier Science Limited, Amsterdam 413-446 (2008)
Co-authors Nanthi Bolan
2007 Gräfe M, Naidu R, 'Remediation of Metal-Contaminated Soils: An Overview', Biophysico-Chemical Processes of Heavy Metals and Metalloids in Soil Environments 565-605 (2007)
DOI 10.1002/9780470175484.ch14
Citations Scopus - 2
2007 Krishnamurti GSR, Naidu R, 'Chemical Speciation and Bioavailability of Trace Metals', Biophysico-Chemical Processes of Heavy Metals and Metalloids in Soil Environments 417-466 (2007)
DOI 10.1002/9780470175484.ch11
Citations Scopus - 14
2006 Bolan N, Mahimairaja S, Mallavarapu M, Naidu R, Adriano DC, 'Biotransformation of arsenic in soil and aquatic environments', Managing Arsenic in the Environment: From Soil to Human Health, CSIRO PUBLISHING, Australia 433-454 (2006)
Co-authors Megh Mallavarapu, Nanthi Bolan
2005 Bolan N, Adriano DC, Naidu R, de la Luz Mora M, Mahimairaja S, 'Phosphorus-trace element interactions in soil-plant systems', Agriculture and the Environment, Soil Science Society of America, South Australia 384-412 (2005)
Co-authors Nanthi Bolan
Show 68 more chapters

Journal article (927 outputs)

Year Citation Altmetrics Link
2024 Hasnain MG, Garcia-Esperon C, Tomari YK, Walker R, Saluja T, Rahman MM, et al., 'Bushfire-smoke trigger hospital admissions with cerebrovascular diseases: Evidence from 2019 20 bushfire in Australia', European Stroke Journal, [C1]
DOI 10.1177/23969873231223307
Co-authors Christopher Levi, Andrew Boyle, Neil Spratt
2024 Cui B, Tian T, Duan L, Rong H, Chen Z, Luo S, et al., 'Towards advanced removal of organics in persulfate solution by heterogeneous iron-based catalyst: A review', Journal of Environmental Sciences (China), (2024) [C1]

Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature, the lack of secondary pollution to th... [more]

Heterogeneous iron-based catalysts have drawn increasing attention in the advanced oxidation of persulfates due to their abundance in nature, the lack of secondary pollution to the environment, and their low cost over the last a few years. In this paper, the latest progress in the research on the activation of persulfate by heterogeneous iron-based catalysts is reviewed from two aspects, in terms of synthesized catalysts (Fe0, Fe2O3, Fe3O4, FeOOH) and natural iron ore catalysts (pyrite, magnetite, hematite, siderite, goethite, ferrohydrite, ilmenite and lepidocrocite) focusing on efforts made to improve the performance of catalysts. The advantages and disadvantages of the synthesized catalysts and natural iron ore were summarized. Particular interests were paid to the activation mechanisms in the catalyst/PS/pollutant system for removal of organic pollutants. Future research challenges in the context of field application were also discussed.

DOI 10.1016/j.jes.2023.06.035
Citations Scopus - 2
2024 Liu Y, Wang F, Wang Z, Xiang L, Fu Y, Zhao Z, et al., 'Soil properties and organochlorine compounds co-shape the microbial community structure: A case study of an obsolete site', Environmental Research, 240 (2024) [C1]

Organochlorine compounds (OCs) such as chlorobenzenes (CB) are persistent organic pollutants that are ubiquitous in soils at organochlorine pesticides (OCP) production sites. Long... [more]

Organochlorine compounds (OCs) such as chlorobenzenes (CB) are persistent organic pollutants that are ubiquitous in soils at organochlorine pesticides (OCP) production sites. Long-term contamination with OCs might alter the soil microbial structure and further affect soil functions. However, the effects of OCs regarding the shaping of microbial community structures in the soils of OCs-contaminated sites remain obscure, especially in the vertical soil profile where pollutants are highly concealed. Hence this paper explored the status and causes of OCs pollution (CB, hexachlorocyclohexane (HCH), and dichlorodiphenyltrichloroethane (DDT)) in an obsolete site, and its combined effects with soil properties (pH, available phosphorus (AP), dissolved organic carbon (DOC), etc) on microbial community structure. The mean total concentration of OCs in the subsoils was up to 996 times higher than that in the topsoils, with CB constituting over 90% of OCs in the subsoil. Historical causes, anthropogenic effects, soil texture, and the nature of OCs contributed to the differences in the spatial distribution of OCs. Redundancy analysis revealed that both the soil properties and OCs were important factors in shaping microbial composition and diversity. Variation partitioning analysis further indicated that soil properties had a greater impact on microbial community structure than OCs. Significant differences in microbial composition between topsoils and subsoils were observed through linear discriminant analysis effect size (LEfSe) analysis, primarily driven by different pollutant conditions. Additionally, co-occurrence network analysis indicated that heavily contaminated subsoils exhibited closer and more intricate bacterial community interactions compared to lightly contaminated topsoils. This work reveals the impact of environmental factors in co-shaping the structure of soil microbial communities. These findings advance our understanding of the intricate interplay among organochlorine pollutants, soil properties, and microbial communities, and provides valuable insights into devising effective management strategies in OCs-contaminated soils.

DOI 10.1016/j.envres.2023.117589
Citations Scopus - 1
2024 Nasif SO, Nuruzzaman M, Naidu R, 'Porous Silica Nanocarriers: Advances in Structural Orientation and Modification to Develop Sustainable Pesticide Delivery Systems', ACS Agricultural Science &amp; Technology, 4 144-172 (2024) [C1]
DOI 10.1021/acsagscitech.3c00436
Co-authors Md Nuruzzaman
2024 Cui B, Rong H, Tian T, Guo D, Duan L, Nkinahamira F, et al., 'Chemical methods to remove microplastics from wastewater: A review.', Environ Res, 249 118416 (2024) [C1]
DOI 10.1016/j.envres.2024.118416
2024 Davamani V, John JE, Poornachandhra C, Gopalakrishnan B, Arulmani S, Parameswari E, et al., 'A Critical Review of Climate Change Impacts on Groundwater Resources: A Focus on the Current Status, Future Possibilities, and Role of Simulation Models', ATMOSPHERE, 15 (2024) [C1]
DOI 10.3390/atmos15010122
Citations Scopus - 1
Co-authors Alvin Lal
2024 Fang C, Luo Y, Naidu R, 'Advancements in Raman imaging for nanoplastic analysis: Challenges, algorithms and future Perspectives', Analytica Chimica Acta, 1290 342069-342069 (2024) [C1]
DOI 10.1016/j.aca.2023.342069
Co-authors Cheng Fang
2024 Fang C, Zhou W, Hu J, Wu C, Niu J, Naidu R, 'Paint has the potential to release microplastics, nanoplastics, inorganic nanoparticles, and hybrid materials', Environmental Sciences Europe, 36 (2024) [C1]

Background: When we paint our houses or offices, we might paint plastic, because most paints are generally formulated with polymer binders. After drying and curing, the binders fi... [more]

Background: When we paint our houses or offices, we might paint plastic, because most paints are generally formulated with polymer binders. After drying and curing, the binders fix the colourants on the painted surface as a film of plastic mixture, which is tested herein using Raman imaging to analyse and directly visualise the hybrid plastic-colourant (titanium dioxide or TiO2 nanoparticles). Results: For the plastic mixture or hybrid, the co-existence and competition between the Raman signals of plastic and TiO2 complicate the individual analysis, which should be carefully extracted and separated in order to avoid the weak signal of plastic to be masked by that of TiO2. This is particularly important when considering the Raman activity of TiO2 is much stronger than that of plastic. Plastic is observed to coat the TiO2 nanoparticle surface, individually or as a bulk to embed the TiO2 nanoparticles as mixture or hybrid. Once branched, pended, scratched or aged, the paint can also be peeled off from the painted surface, including gyprock, wood and glass, releasing microplastics and nanoplastics (coating onto the individual TiO2 nanoparticle surface or embedding the TiO2 nanoparticles, or individually as particles) in potential. Conclusions: Our test sends us a warning that we are surrounded by plastic items that might release microplastics and nanoplastics in potential, for which the risk assessment is needed. Overall, Raman imaging is a suitable approach to effectively characterise microplastics and nanoplastics, even from the mixture with the hybrid background and the complicated interference. Graphical Abstract: [Figure not available: see fulltext.]

DOI 10.1186/s12302-024-00844-6
Co-authors Cheng Fang
2024 Fang C, Awoyemi OS, Saianand G, Xu L, Niu J, Naidu R, 'Characterising microplastics in indoor air: Insights from Raman imaging analysis of air filter samples', Journal of Hazardous Materials, 464 (2024) [C1]

We are directly exposed to microplastic contamination via indoor air that we breathe daily, for which the characterisation of microplastics is still a challenge. Herein, two typic... [more]

We are directly exposed to microplastic contamination via indoor air that we breathe daily, for which the characterisation of microplastics is still a challenge. Herein, two typical air filter samples were collected, one from an air-conditioner and another from a personal computer, both of which have been working for around half a year to collect and accumulate microplastics in the indoor air, like microplastic banks. After the sample preparation to remove the mineral dusts, Raman imaging was employed to directly and simultaneously identify and visualise microplastics of polyethylene terephthalate (PET) fibres, distinguish them from other fibres such as cellulose and cross-check them with a scanning electron microscope (SEM). To count the microplastics and to avoid the quantification bias, several areas were randomly scanned and imaged to statistically estimate the percentage of microplastic fibres in the analysed samples. The microplastics amount, which has been estimated at 73¿88,000 fibers per filter per half a year, varies and depends on the indoor environment so that the air filter can work as a good indicator to monitor the quality of the indoor air from the microplastic perspective. Overall, human are directly exposed to this emerging contamination every day, raising environmental concerns. Raman imaging characterisation and its corresponding statistical information can help pursue further research on microplastics.

DOI 10.1016/j.jhazmat.2023.132969
Co-authors Cheng Fang
2024 Umeh AC, Naidu R, Olisa E, Liu Y, Qi F, Bekele D, 'A systematic investigation of single solute, binary and ternary PFAS transport in water-saturated soil using batch and 1-dimensional column studies: Focus on mixture effects.', Journal of hazardous materials, 461 132688 (2024) [C1]
DOI 10.1016/j.jhazmat.2023.132688
Citations Scopus - 2Web of Science - 1
Co-authors Yanju Liu, Dawit Bekele, Anthony Umeh
2024 Luo Y, Awoyemi O, Liu S, Niu J, Naidu R, Fang C, 'From celebration to contamination: Analysing microplastics released by burst balloons.', J Hazard Mater, 464 133021 (2024) [C1]
DOI 10.1016/j.jhazmat.2023.133021
Co-authors Cheng Fang
2024 Wang L, Gopalan S, Naidu R, 'Advancements in nanotechnological approaches to volatile organic compound detection and separation', Current Opinion in Environmental Science &amp; Health, 37 100528-100528 (2024)
DOI 10.1016/j.coesh.2023.100528
Co-authors Liang Wang, Saianand Gopalan
2023 Rahman Z, Thomas L, Chetri SPK, Bodhankar S, Kumar V, Naidu R, 'A comprehensive review on chromium (Cr) contamination and Cr(VI)-resistant extremophiles in diverse extreme environments.', Environ Sci Pollut Res Int, 30 59163-59193 (2023) [C1]
DOI 10.1007/s11356-023-26624-y
Citations Scopus - 4
2023 Wang L, Cheng Y, Wu C, Luo F, Lin Z, Naidu R, 'Rapid on-site detection of underground petroleum pipeline leaks and risk assessment using portable gas chromatography-mass spectrometry and solid phase microextraction.', J Chromatogr A, 1696 463980 (2023) [C1]
DOI 10.1016/j.chroma.2023.463980
Co-authors Ying Cheng, Liang Wang
2023 Fang C, Luo Y, Naidu R, 'Super-resolution imaging of micro- and nanoplastics using confocal Raman with Gaussian surface fitting and deconvolution', Talanta, 265 124886-124886 (2023) [C1]
DOI 10.1016/j.talanta.2023.124886
Citations Scopus - 4
Co-authors Cheng Fang
2023 Fang C, Naidu R, 'A review of perchlorate contamination: Analysis and remediation strategies.', Chemosphere, 338 139562 (2023) [C1]
DOI 10.1016/j.chemosphere.2023.139562
Citations Scopus - 2
Co-authors Cheng Fang
2023 Islam MM, Mohana AA, Rahman MA, Rahman M, Naidu R, Rahman MM, 'A Comprehensive Review of the Current Progress of Chromium Removal Methods from Aqueous Solution', TOXICS, 11 (2023) [C1]
DOI 10.3390/toxics11030252
Citations Scopus - 8Web of Science - 3
Co-authors Mahmud Rahman
2023 Luo Y, Naidu R, Fang C, 'Raman imaging towards in-situ visualisation of perchlorate adsorption', Water Research, 229 (2023) [C1]

Raman imaging can directly visualise perchlorate adsorption, and even enables in-situ monitoring, because water has a low Raman activity and generates almost no interference, whic... [more]

Raman imaging can directly visualise perchlorate adsorption, and even enables in-situ monitoring, because water has a low Raman activity and generates almost no interference, which is demonstrated herein. The Raman signal enhancement of perchlorate on the porous silver surface provides a possibility to monitor the adsorption of perchlorate at low level. From this initial adsorption assembly of (i) porous silver-perchlorate, we test several more, including (ii) porous silver-perchlorate-sand, (iii) porous silver-perchlorate-microplastic-sand, (iv) porous silver-perchlorate-microplastic-sand-river water etc. The introduction of microplastic, another emerging contaminant, can provide extra insights into the co-adsorption process. Particularly the composite structure of microplastic-sand can simultaneously visualise the adsorption of perchlorate on the silver surface, the plastic/organic surface and the sand surface. We note that the water can modify the configuration of perchlorate in-situ towards the adsorption on silver surface; the adsorption of perchlorate can benefit from co-adsorption with organic matter, and the rough surface plays an important role as well. Overall, Raman imaging provides an effective approach to directly visualise the adsorption of emerging contaminants.

DOI 10.1016/j.watres.2022.119510
Citations Scopus - 4
Co-authors Cheng Fang
2023 Fang C, Luo Y, Naidu R, 'Super-resolution Raman imaging towards visualisation of nanoplastics', ANALYTICAL METHODS, 15 5300-5310 (2023)
DOI 10.1039/d3ay01176c
Co-authors Cheng Fang
2023 Sarkar MIU, Shahriar S, Naidu R, Rahman MM, 'Concentrations of potentially toxic and essential trace elements in marketed rice of Bangladesh: Exposure and health risks', Journal of Food Composition and Analysis, 117 (2023) [C1]

Rice is a major dietary source of essential trace elements required for the human body but also can be an exposure pathway to different potentially toxic trace elements. This stud... [more]

Rice is a major dietary source of essential trace elements required for the human body but also can be an exposure pathway to different potentially toxic trace elements. This study determined various essential and toxic trace elements in rice from Bangladeshi markets and their possible health risks. Concentrations of essential and toxic trace elements in rice varied significantly from location to location. Mean concentrations (mg kg-1 as dry weight) of essential trace elements were found in the following order - Zn>Mn>Cu>Fe>Mo>Se>Co - and were within their maximum allowable limits. The average concentrations (mg kg-1) of toxic trace elements were as follows: As: 0.17, Cr: 0.18, Ni: 0.55 and Pb: 0.18, while 7% and 40% of the rice samples surpassed, respectively, the EU recommended limits of As and Pb. This study revealed that rice could be a primary exposure pathway of toxic elements, leading to either noncarcinogenic or carcinogenic health problems for daily rice consumers. The non-carcinogenic health risk was mainly associated with As which contributed 77% to the hazard index. The carcinogenic risk measured as incremental lifetime cancer risk (ILCR) was high (>10-4) with As, Cr and Ni, while Pb showed a moderate (<10-4) carcinogenic risk to adults. Rice can substantially be contaminated by trace elements other than As with potential human health risks. Consequently, regular monitoring of the marketed rice grain is demanded, backed up by viable mitigation strategies for reducing toxic elements uptake by rice grains.

DOI 10.1016/j.jfca.2022.105109
Citations Scopus - 3
Co-authors Mahmud Rahman
2023 Al Amin M, Luo Y, Shi F, Yu L, Liu Y, Nolan A, et al., 'A modified TOP assay to detect per- and polyfluoroalkyl substances in aqueous film-forming foams (AFFF) and soil.', Front Chem, 11 1141182 (2023) [C1]
DOI 10.3389/fchem.2023.1141182
Co-authors Megh Mallavarapu, Cheng Fang, Yanju Liu
2023 Paul SK, Xi Y, Sanderson P, Deb AK, Islam MR, Naidu R, 'Investigation of herbicide sorption-desorption using pristine and organoclays to explore the potential carriers for controlled release formulation.', Chemosphere, 337 139335 (2023) [C1]
DOI 10.1016/j.chemosphere.2023.139335
Citations Scopus - 1
Co-authors Mdrashidul Islam
2023 Luo Y, Awoyemi OS, Naidu R, Fang C, 'Detection of microplastics and nanoplastics released from a kitchen blender using Raman imaging', Journal of Hazardous Materials, 453 131403-131403 (2023) [C1]
DOI 10.1016/j.jhazmat.2023.131403
Citations Scopus - 8
Co-authors Cheng Fang
2023 Samarasinghe SVAC, Krishnan K, Aitken RJ, Naidu R, Megharaj M, 'Chronic effects of TiO2 and ZnO nanoparticles to earthworm Eisenia fetida', Environmental Chemistry and Ecotoxicology, 5 129-134 (2023) [C1]
DOI 10.1016/j.enceco.2023.04.001
Co-authors Chamila Samarasinghe, Megh Mallavarapu, John Aitken
2023 Wang L, Cheng Y, Gopalan S, Luo F, Amreen K, Singh RK, et al., 'Review and Perspective: Gas Separation and Discrimination Technologies for Current Gas Sensors in Environmental Applications.', ACS Sens, 8 1373-1390 (2023) [C1]
DOI 10.1021/acssensors.2c02810
Citations Scopus - 8
Co-authors Liang Wang, Saianand Gopalan, Ying Cheng
2023 Al Amin M, Luo Y, Nolan A, Mallavarapu M, Naidu R, Fang C, 'Thermal kinetics of PFAS and precursors in soil: Experiment and surface simulation in temperature-time plane.', Chemosphere, 318 138012 (2023) [C1]
DOI 10.1016/j.chemosphere.2023.138012
Citations Scopus - 1
Co-authors Cheng Fang, Megh Mallavarapu
2023 Al-Gheethi AA, Alagamalai RA, Noman EA, Saphira Radin Mohamed RM, Naidu R, 'Degradation of cephalexin toxicity in non-clinical environment using zinc oxide nanoparticles synthesized in Momordica charantia extract; Numerical prediction models and deep learning classification', Chemical Engineering Research and Design, 192 180-193 (2023) [C1]

Antibiotics in nonclinical environments represent a serious risk to human health due to their role in the antimicrobial resistance. The present study aimed to optimise the detoxif... [more]

Antibiotics in nonclinical environments represent a serious risk to human health due to their role in the antimicrobial resistance. The present study aimed to optimise the detoxification of cephalexin (CFX) by the Momordica charantia extract zinc oxide nanoparticle catalyst (MCZnO NPs) as a function of dosage of ZnO NPs, time, pH and CFX using the artificial neural network model (ANN). The effect was simulated using deep learning analysis to evaluate and explain the behaviour of CFX degradation. Interactions between these factors and the classification of the photocatalysis (low, medium, average, good and high) were analyzed using factor of principal component analysis (F, PCA), discriminant analysis (DA) and Agglomerative hierarchical clustering (AHC). MCZnO NPs have a white colour, spherical shape, non-agglomerated, smooth surface and size-wise they ranged from 50 to 100 nm. The ANN results indicated that 88.87% of CFX was degraded using 50 mg/L of MCZnO NP, 40 mg/L of CFX, at pH 9, and after 180 min. Simulation analysis revealed that MCZnO NPs were efficient in degrading CFX concentrations (up to 60 mg/L) with 100% removed depending on pH and time. The interaction between F1 and F2 was 94.59% at which pH (x2) and CFX (x4)factors exhibited a high correlation with a synergistic effect on CFX degradation, 20% of the degradation of CFX could be classified as a high percentage (>90%). These findings reflected the role of deep learning analysis in understanding the behavior of CFX for the degradation process.

DOI 10.1016/j.cherd.2023.02.032
Citations Scopus - 3
2023 Unnithan A, Bekele D, Samarasinghe C, Chadalavada S, Naidu R, 'Evaluating the role of preferential pathways in exacerbating vapour intrusion risks', Journal of Hazardous Materials Advances, 10 100310-100310 (2023) [C1]
DOI 10.1016/j.hazadv.2023.100310
Co-authors Sreenivasulu Chadalavada, Dawit Bekele, Chamila Samarasinghe
2023 Luo Y, Naidu R, Fang C, 'Accelerated transformation of plastic furniture into microplastics and nanoplastics by fire.', Environ Pollut, 317 120737 (2023) [C1]
DOI 10.1016/j.envpol.2022.120737
Citations Scopus - 5Web of Science - 5
Co-authors Cheng Fang
2023 Khan AUH, Liu Y, Fang C, Naidu R, Shon HK, Rogers Z, Dharmarajan R, 'A comprehensive physicochemical characterization of zinc oxide nanoparticles extracted from sunscreens and wastewaters', Environmental Advances, 12 100381-100381 (2023) [C1]
DOI 10.1016/j.envadv.2023.100381
Citations Scopus - 3
Co-authors Cheng Fang, Yanju Liu
2023 Majid N, Bahar MM, Harper R, Megharaj M, Naidu R, 'Influence of biotic and abiotic factors on the development of non-wetting soils and management approaches: A review', Soil Security, 11 100091-100091 (2023) [C1]
DOI 10.1016/j.soisec.2023.100091
Citations Scopus - 1
Co-authors Megh Mallavarapu, Mezbaul Bahar
2023 Fang C, Gopalan S, Zhang X, Xu L, Niu J, Naidu R, 'Raman imaging to identify microplastics released from toothbrushes: algorithms and particle analysis.', Environ Pollut, 337 122510 (2023) [C1]
DOI 10.1016/j.envpol.2023.122510
Co-authors Cheng Fang, Saianand Gopalan
2023 Fang C, Luo Y, Naidu R, 'Microplastics and nanoplastics analysis: Options, imaging, advancements and challenges', TrAC Trends in Analytical Chemistry, 166 117158-117158 (2023) [C1]
DOI 10.1016/j.trac.2023.117158
Citations Scopus - 11
Co-authors Cheng Fang
2023 Ghavamifar S, Naidu R, Mozafari V, Li Z, 'Can calcite play a role in the adsorption of glyphosate? A comparative study with a new challenge.', Chemosphere, 311 136922 (2023) [C1]
DOI 10.1016/j.chemosphere.2022.136922
Citations Scopus - 1Web of Science - 1
2023 Wijayawardena MAA, Yan K, Liu Y, Naidu R, 'Can the mouse model successfully predict mixed metal(loid)s bioavailability in humans from contaminated soils?', Chemosphere, 311 137113 (2023) [C1]
DOI 10.1016/j.chemosphere.2022.137113
Citations Scopus - 4
Co-authors Yanju Liu, Ayanka Wijayawardena
2023 Islam MR, Sanderson P, Johansen MP, Payne TE, Naidu R, 'Environmental chemistry response of beryllium to diverse soil-solution conditions at a waste disposal site.', Environmental science. Processes & impacts, 25 94-109 (2023) [C1]
DOI 10.1039/d2em00313a
Citations Scopus - 1Web of Science - 1
Co-authors Mdrashidul Islam
2023 Fang C, Luo Y, Naidu R, 'Super-resolution Raman imaging towards visualisation of nanoplastics.', Anal Methods, 15 5300-5310 (2023) [C1]
DOI 10.1039/d3ay01176c
Citations Scopus - 2
Co-authors Cheng Fang
2023 Hasnain MG, Garcia-Esperon C, Tomari YK, Walker R, Saluja T, Rahman MM, et al., 'Effect of short-term exposure to air pollution on daily cardio- and cerebrovascular hospitalisations in areas with a low level of air pollution', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 30 102438-102445 (2023)
DOI 10.1007/s11356-023-29544-z
Co-authors Christopher Levi, Andrew Boyle, Neil Spratt
2023 Dietrich M, Barlow CF, Entwistle JA, Meza-Figueroa D, Dong C, Gunkel-Grillon P, et al., 'Predictive modeling of indoor dust lead concentrations: Sources, risks, and benefits of intervention', Environmental Pollution, 319 (2023) [C1]

Lead (Pb) contamination continues to contribute to world-wide morbidity in all countries, particularly low- and middle-income countries. Despite its continued widespread adverse e... [more]

Lead (Pb) contamination continues to contribute to world-wide morbidity in all countries, particularly low- and middle-income countries. Despite its continued widespread adverse effects on global populations, particularly children, accurate prediction of elevated household dust Pb and the potential implications of simple, low-cost household interventions at national and global scales have been lacking. A global dataset (~40 countries, n = 1951) of community sourced household dust samples were used to predict whether indoor dust was elevated in Pb, expanding on recent work in the United States (U.S.). Binned housing age category alone was a significant (p < 0.01) predictor of elevated dust Pb, but only generated effective predictive accuracy for England and Australia (sensitivity of ~80%), similar to previous results in the U.S. This likely reflects comparable Pb pollution legacies between these three countries, particularly with residential Pb paint. The heterogeneity associated with Pb pollution at a global scale complicates the predictive accuracy of our model, which is lower for countries outside England, the U.S., and Australia. This is likely due to differing environmental Pb regulations, sources, and the paucity of dust samples available outside of these three countries. In England, the U.S., and Australia, simple, low-cost household intervention strategies such as vacuuming and wet mopping could conservatively save 70 billion USD within a four-year period based on our model. Globally, up to 1.68 trillion USD could be saved with improved predictive modeling and primary intervention to reduce harmful exposure to Pb dust sources.

DOI 10.1016/j.envpol.2023.121039
2023 Umeh AC, Stegh J, Naidu R, 'Toward In Situ Sequestration of Multicomponent PFAS Using Injectable Adsorbent Suspensions', ACS ES&amp;T Water, 3 3858-3873 (2023) [C1]
DOI 10.1021/acsestwater.3c00287
Co-authors Anthony Umeh
2023 Bharos AMK, Vishwakarma A, Bharos A, Naidu R, 'Diversity and conservation status of avifauna in the Surguja region, Chhattisgarh, India', Journal of Threatened Taxa, 15 23710-23728 (2023) [C1]

This study is aimed at updating the avifauna status and to assess major threats in six districts of the Surguja region of northern Chhattisgarh. The avifauna of this region is les... [more]

This study is aimed at updating the avifauna status and to assess major threats in six districts of the Surguja region of northern Chhattisgarh. The avifauna of this region is less studied as compared to the central and southern regions of the state. Chhattisgarh has unique and important habitats for bird species. The geographical region has two major forest types which provide a suitable habitat for many terrestrial and numerous wetlands that support aquatic bird species. The northern region is a basin of rivers Hasdeo and Rihand, prominently forested and a major coal belt. In this study, planned and opportunistic surveys were done in different seasons, and data was collected from 1995 to 2019. In the northern Chhattisgarh region,we have compiled all-district data and a total of 361 bird species were recorded. The maximum number of bird species were recorded from Koriya 318, followed by Raigarh 262, Surguja 162, Balrampur 260, Surajpur 208, and Jashpur 254. Species recorded include three Critically Endangered (CR), two Endangered (EN), five Vulnerable (VU), and 13 Near Threatened (NT). Nesting of Lesser Adjutant, Indian Vulture, White-rumped Vulture, Egyptian Vulture, and sighting of Sarus Crane in Surguja region is reported. The study also revealed the presence of nine Himalayan and sub-Himalayan species. Comparing with previous studies 117 new species were found. Chhattisgarh has ample potential and opportunities for new records as many regions have not yet been adequately explored, it can be a key birding hub for bird lovers as well as the scientific community. The large-scale miningoriented activities, hunting, and poaching are posing serious threats, which will have a direct or indirect, impact on the future of the avifauna of the region.

DOI 10.11609/jott.7314.15.8.23710-23728
2023 Biswas B, Islam MR, Deb AK, Greenaway A, Warr LN, Naidu R, 'Understanding Iron Impurities in Australian Kaolin and Their Effect on Acid and Heat Activation Processes of Clay', ACS Omega, 8 5533-5544 (2023) [C1]

Iron impurities present in the crystal structure of kaolin minerals or in accessory species are frequently encountered in clay deposits. As knowledge of the location and states of... [more]

Iron impurities present in the crystal structure of kaolin minerals or in accessory species are frequently encountered in clay deposits. As knowledge of the location and states of the iron is crucial when modifying the properties of clays by activation, it is important that new deposits are well characterized in terms of the amount and location of this metal. The Western Australia Noombenberry deposit has been identified as a large resource of kaolin composed largely of halloysite and kaolinite. We sampled six from one hundred drill holes and grouped them according to major mineral and iron impurities. First, we characterized them to understand the source of iron impurities. Then, we performed three physicochemical activation processes of samples involving acid treatment (by 3 M HCl), heating at 600 °C, and a combination of both. State-of-the-art tools, including X-ray diffraction, X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, and nuclear magnetic resonance, revealed the properties of kaolin, iron impurities, and the changes incurred after activation. The iron impurities were found to be linked to non-kaolin minerals, i.e., in mica or illite. Once the iron was removed mainly by acid activation, the surface area, pore volume, and negative surface charges increased, and that was significant for halloysite-rich samples. These properties helped adsorb N2 gas compared to the raw kaolin. Therefore, knowing the iron¿s location and states in associated mineral species and their dissolution/retention may expand the scope of material development for gas adsorption. They are also useful in other applications like clay purification and adsorbent or additive formulations.

DOI 10.1021/acsomega.2c06795
Citations Scopus - 2
Co-authors Mdrashidul Islam, Bhaba Biswas
2023 Lei Y, Hou J, Fang C, Tian Y, Naidu R, Zhang J, et al., 'Ultrasound-based advanced oxidation processes for landfill leachate treatment: Energy consumption, influences, mechanisms and perspectives.', Ecotoxicol Environ Saf, 263 115366 (2023) [C1]
DOI 10.1016/j.ecoenv.2023.115366
Citations Scopus - 3
Co-authors Cheng Fang
2023 Vidane Arachchige Chamila Samarasinghe S, Krishnan K, John Aitken R, Naidu R, Megharaj M, 'Multigenerational effects of TiO2 rutile nanoparticles on earthworms.', Environ Pollut, 336 122376 (2023) [C1]
DOI 10.1016/j.envpol.2023.122376
Co-authors John Aitken, Megh Mallavarapu, Chamila Samarasinghe
2023 Islam MR, Sanderson P, Payne TE, Naidu R, 'Synthesised and modified zeolite for effective management of beryllium contaminants in aqueous media under different conditions.', Sci Total Environ, 904 166384 (2023) [C1]
DOI 10.1016/j.scitotenv.2023.166384
Co-authors Mdrashidul Islam
2023 Sarkar MIU, Islam S, Hosain MT, Naidu R, Rahman MM, 'Distribution of essential and non-essential elements in rice-based products sold in Australian markets: Exposure assessment', Journal of Food Composition and Analysis, 120 (2023) [C1]

Rice-derived food products could be a major dietary source of both essential and non-essential elements to people; hence it is crucial to assess their concentrations to ensure the... [more]

Rice-derived food products could be a major dietary source of both essential and non-essential elements to people; hence it is crucial to assess their concentrations to ensure the safe consumption of these products. In this study, six different types of rice-based products collected from Australian markets were analysed for essential and non-essential elements to evaluate the exposure and health risk. The estimated intake (EI) of essential elements from baby rice substantially contributed to the recommended dietary allowance of Fe (27%) and Mn (43%) for infants compared to different rice-based products for children and adults. The EI values of Cd, Cr, Ni and Pb were 0.15 ¿ 1.17, 5.68 ¿ 16.24, 7.47 ¿ 16.24 and 0.40 ¿ 1.21 µg, respectively, from an average recommended serving of different rice-based products. Compared to the tolerable daily intake (TDI) and tolerable weekly intake (TWI) provided by the European Food Safety Authority (EFSA), both average daily intake (ADI) and average weekly intake (AWI) values of the respective non-essential elements were much lower. Thus, this study results indicated that the rice-based products pose no potential health risk to consumers although regular monitoring is necessary to reduce health risks especially for infants and children.

DOI 10.1016/j.jfca.2023.105339
Co-authors Mahmud Rahman
2023 Lei Y, Zhao L, Fang C, Naidu R, Tian D, Zhao L, et al., 'A novel enhanced defluorination of perfluorooctanoic acids by surfactant-assisted ultrasound coupling persulfate', Separation and Purification Technology, 317 (2023) [C1]

A novel enhanced defluorination of perfluorooctanoic acids (PFOA) by surfactant-assisted ultrasound (US) coupling persulfate (PS) was proposed in this study. Instead of adding the... [more]

A novel enhanced defluorination of perfluorooctanoic acids (PFOA) by surfactant-assisted ultrasound (US) coupling persulfate (PS) was proposed in this study. Instead of adding the surfactant into the PFOA solution directly, the promoted defluorination was obtained by adding the surfactant to the US bath outside of the PFOA reactor. In this situation, the effects of the critical micelle concentration (CMC), concentration and type of the surfactant, the US frequency and the pH of the US bath liquid on the PFOA defluorination were investigated. The results demonstrated that the PFOA defluorination at low-frequency levels (25 kHz-59 kHz) was facilitated by raising US frequency. Besides, the addition of three surfactants (Triton X-100, sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB)) all increased the PFOA defluorination by Triton X-100 > CTAB > SDS, which is opposed to their CMC (Triton X-100: 0.28 mM<CTAB: 1.07 mM<SDS: 7.69 mM). Rising the surfactant concentration would not enhance the defluorination, the best one was obtained at its CMC. Moreover, changing the pH of the US bath liquid by adding acid or alkaline solution inhibited the defluorination, which might be attributed to acid or base causing damage to the chemical properties or physical structure of surfactant (certified by the SEM tests). Additionally, the mechanism of enhanced PFOA defluorination was examined by electron paramagnetic resonance analysis, which proved that adding surfactant facilitated the generation of the radicals (·OH and SO4·-), as well as the radicals¿ amount increased over time during 60 min. Finally, the inhibited defluorination of adding surfactant directly to the PFOA solution was studied by the SEM analysis, the results demonstrated that adsorption and wrapping between surfactant micelles and PFOA reduced the contact between PFOA and radicals and affected the surfactant effect on the surface tension.

DOI 10.1016/j.seppur.2023.123906
Citations Scopus - 5
Co-authors Cheng Fang
2023 Warner SD, Bekele D, Nathanail CP, Chadalavada S, Naidu R, 'Climate-influenced hydrobiogeochemistry and groundwater remedy design: A review', Remediation Journal, 33 187-207 (2023) [C1]
DOI 10.1002/rem.21753
Citations Scopus - 1Web of Science - 1
Co-authors Sreenivasulu Chadalavada, Dawit Bekele
2023 Samarasinghe SVAC, Bahar MM, Qi F, Yan K, Liu Y, Naidu R, 'Evaluating PFHxS toxicity to invertebrates and microbial processes in soil', Environmental Chemistry and Ecotoxicology, 5 120-128 (2023) [C1]
DOI 10.1016/j.enceco.2023.03.003
Co-authors Mezbaul Bahar, Chamila Samarasinghe, Yanju Liu
2023 Rathnayake IVN, Megharaj M, Naidu R, 'Sol-Gel Immobilized Optical Microalgal Biosensor for Monitoring Cd, Cu and Zn Bioavailability in Freshwater.', Bull Environ Contam Toxicol, 110 73 (2023) [C1]
DOI 10.1007/s00128-023-03709-5
Citations Scopus - 3
Co-authors Megh Mallavarapu
2023 Yu L, Duan L, Naidu R, Meng F, Semple KT, 'Effects of source materials on desorption kinetics of carcinogenic PAHs from contaminated soils', Chemosphere, 335 (2023) [C1]

Research investigating the desorptive behaviour of PAHs from contaminated soils often overlooked the effects of source materials, especially coal tar and coal tar pitch and materi... [more]

Research investigating the desorptive behaviour of PAHs from contaminated soils often overlooked the effects of source materials, especially coal tar and coal tar pitch and materials alike. In this study, a refined experimental approach was adopted to establish a simple-to-complex continuum of systems that allow the investigation of desorption kinetics of benzo(a)pyrene (BaP) and 3 other carcinogenic PAHs (cPAHs) over an incubation period of 48 d. By comparing the modelled desorption parameters, elucidation of the effects of PAH source materials on their desorptive behaviour was achieved. Desorption of cPAHs from coal tar and pitch was enhanced when they were added to soils, with rapidly desorbing fraction (Frap) of BaP increased from 0.68% for pitch to 1.10% and 2.66% for pitch treated soils, and from 2.57% for coal tar to 6.24% for coal tar treated soil G and 8.76% for coal tar treated sand (1 d). At 1 d, desorption of target cPAHs from solvent and source material spiked soils generally followed the order of solvent > coal tar > pitch. Increases in Frap of cPAHs were observed in coal tar-treated soils after 48 d soil incubation (0.33%¿1.16% for soil M, p = 0.05, 6.24%¿9.21% for soil G, p < 0.05) and was attributed to the continuous migration of coal tar as a non-aqueous phase liquid (NAPL) into soil pore structures. Slow desorption was dominated by source materials, whereas the extents and rates of rapid desorption (Frap and krap) were more controlled by the quantity of soil organic matter (SOM), rather than quality of SOM (as in solvent-spiked soils). The results of this study challenged the role of PAH source materials as ¿sinks¿ and led to the proposed roles of coal tar and pitch and source materials alike as ¿reservoirs¿ with a risk-driven perspective.

DOI 10.1016/j.chemosphere.2023.139095
2023 Sanchez-Hernandez JC, Narváez C, Cares XA, Sabat P, Naidu R, 'Predicting the bioremediation potential of earthworms of different ecotypes through a multi-biomarker approach.', Sci Total Environ, 862 160547 (2023) [C1]
DOI 10.1016/j.scitotenv.2022.160547
Citations Scopus - 2
2023 Kumar Paul S, Xi Y, Sanderson P, Naidu R, 'Investigation of the physicochemical properties of amine-modified organoclays influenced by system pH and their potential to adsorb anionic herbicide', Geoderma, 436 (2023) [C1]

Organically modified montmorillonites have already attracted the attention of researchers due to their eco-friendly characteristics and versatile application in our daily lives. T... [more]

Organically modified montmorillonites have already attracted the attention of researchers due to their eco-friendly characteristics and versatile application in our daily lives. Their application is now being widely explored as a potential carrier for preparing solid-laden controlled release formulations (CRFs) of herbicides. The suitability of a new formulation mainly depends on herbicide releasing behaviour under various conditions, which is governed by the interaction mechanisms between carrier materials and target herbicide. The physicochemical properties of carriers and herbicides are the key components for establishing the probable interaction mechanisms between them. The physicochemical properties of amine-modified organoclays are mostly pH dependent and this experiment investigated the effect of pH on surface chemistry and how it changes when system pH is varied. Results revealed that the organoclays converted from protonated to deprotonated conditions as well as from hydrophobic to hydrophilic states with increasing system pH, from acidic to alkaline conditions. The release of surfactants from the organoclays was higher in acidic and alkaline pH conditions than in neutral pH. The release of major structural elements was highest in acidic conditions, but gradually abated with increasing system pH until neutral conditions were achieved. After that they increased slightly to an alkaline state, except for iron (Fe). Zeta values of both organoclays gradually diminished as system pH increased. The surface area of organoclays was highest at neutral pH, and gradually waned towards acidic and alkaline pH. This ultimately affects adsorption of anionic herbicide onto the various pH-adjusted organoclays. The adsorption was highest at around the pKa value of the herbicide and gradually declined with increasing system pH to a neutral state, and then slightly increased towards a higher pH. Based on this, it can be concluded that system pH exerts a significant influence on the physicochemical properties of amine-modified organoclays. This may affect firstly, adsorption of pesticides onto the interlayer gallery of the organoclays for CRFs of pesticides; and secondly, the formulation's releasing behaviour and ultimate efficacy of the synthesised formulation.

DOI 10.1016/j.geoderma.2023.116560
2023 Wang W, Gao Y, Du J, Zheng L, Kong X, Wang H, et al., 'Dose effect of nitrogen regulation on the bioremediation of diesel contaminated soil', Environmental Technology and Innovation, 32 (2023) [C1]

Nitrogen regulation is an effective method to enhance the bioremediation of hydrocarbon contamination. In this study, various dosages of two types of nitrogen sources were spiked ... [more]

Nitrogen regulation is an effective method to enhance the bioremediation of hydrocarbon contamination. In this study, various dosages of two types of nitrogen sources were spiked to the diesel contaminated soil in a 60-day microcosmic experiment. The results showed that the total petroleum hydrocarbon (TPH) degradation rate improved from control test of 32.03% to the highest of 44.74% with nitrogen spiking. Peptone and KNO3 significantly improved the bioremediation of diesel-contaminated soil, peptone was more effective than KNO3 at low dosage. The soil C:N ratio of 20:1 (T1 treatment with the addition of peptone) was the optimal treatment. The effect of two nitrogen on soil pH was reverse, high dose of peptone addition significantly increased soil pH, but KNO3 addition significantly decreased soil pH. The soil bacteria diversity decreased significantly in the high dose Peptone treated soil, while the changes of bacteria diversity of KNO3 treated soil was just opposite. Furthermore, nitrogen regulation significantly changed the structure of soil bacterial community, Rubrobacter, Solirubrobacter and Gaiella, which belonging to Actinomycetota, were identified as the three common genus with hydrocarbon degrading ability in different nitrogen amended soil. Peptone and KNO3 had different mechanisms on the bioremediation of diesel contaminated soil. The properties of these two nitrogen sources provides us with more options for the bioremediation of hydrocarbon contaminated acid or alkaline soil.

DOI 10.1016/j.eti.2023.103245
Citations Scopus - 3
2023 Luo Y, Khoshyan A, Al Amin M, Nolan A, Robinson F, Fenstermacher J, et al., 'Ultrasound-enhanced Magnéli phase Ti

Per-and polyfluoroalkyl substances (PFAS) remediation is still a challenge. In this study, we propose a hybrid system that combines electrochemical treatment with ultrasound irrad... [more]

Per-and polyfluoroalkyl substances (PFAS) remediation is still a challenge. In this study, we propose a hybrid system that combines electrochemical treatment with ultrasound irradiation, aiming for an enhanced degradation of PFAS. Equipped with a titanium suboxide (Ti4O7) anode, the electrochemical cell is able to remove perfluorooctanoic acid (PFOA) effectively. Under the optimal conditions (50 mA/cm2 current density, 0.15 M Na2SO4 supporting electrolyte, and stainless steel/Ti4O7/stainless steel electrode configuration with a gap of ~10 mm), the electrochemical process achieves ~100 % PFOA removal and 43 % defluorination after 6 h. Applying ultrasound irradiation (130 kHz) alone offers a limited PFOA removal, with 33 % PFOA removal and 5.5 % defluorination. When the electrochemical process is combined with ultrasound irradiation, we observe a significant improvement in the remediation performance, with ~100 % PFOA removal and 63.5 % defluorination, higher than the sum of 48.5 % (43 % achieved by the electrochemical process, plus 5.5 % by the ultrasound irradiation), implying synergistic removal/oxidation effects. The hybrid system also consistently shows the synergistic defluorination during degradation of other PFAS and the PFAS constituents in aqueous film forming foam (AFFF). We attribute the synergistic effect to an activated/cleaned electrode surface, improved mass transfer, and enhanced production of radicals.

DOI 10.1016/j.scitotenv.2022.160836
Citations Scopus - 2
Co-authors Cheng Fang, Megh Mallavarapu
2023 Chen Y, Hassan M, Nuruzzaman M, Zhang H, Naidu R, Liu Y, Wang L, 'Iron-modified biochar derived from sugarcane bagasse for adequate removal of aqueous imidacloprid: sorption mechanism study', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 30 4754-4768 (2023) [C1]
DOI 10.1007/s11356-022-22357-6
Citations Scopus - 9Web of Science - 2
Co-authors Yanju Liu, Md Nuruzzaman
2023 Fang C, Gopalan S, Yu J, Naidu R, 'Unveiling microplastics from zippers: Characterisation and visualisation through Raman imaging analysis.', Sci Total Environ, 904 166235 (2023) [C1]
DOI 10.1016/j.scitotenv.2023.166235
Citations Scopus - 1
Co-authors Saianand Gopalan, Cheng Fang
2023 Hasnain MG, Garcia-Esperon C, Tomari YK, Walker R, Saluja T, Rahman MM, et al., 'Effect of short-term exposure to air pollution on daily cardio- and cerebrovascular hospitalisations in areas with a low level of air pollution.', Environ Sci Pollut Res Int, 30 102438-102445 (2023) [C1]
DOI 10.1007/s11356-023-29544-z
Citations Scopus - 1
Co-authors Andrew Boyle, Christopher Levi, Neil Spratt
2023 Ogburn NJ, Duan L, Subashchandrabose SR, Sorgeloos P, O'Connor W, Megharaj M, Naidu R, 'Agricultural wastes for brine shrimp Artemia production: A review', Reviews in Aquaculture, 15 1159-1178 (2023) [C1]

An increasing global population has meant aquaculture, one of the fastest growing food industry sectors, faces significant sustainability challenges as it tries to address the ris... [more]

An increasing global population has meant aquaculture, one of the fastest growing food industry sectors, faces significant sustainability challenges as it tries to address the rising global protein demand. In many sectors, production is underpinned by fishmeal as dietary ingredient, but this is a finite resource with competing users from the poultry and livestock industries. Alternatively, some (planktonic) aquatic species, especially brine shrimp Artemia, can be produced using agricultural waste to provide food or biomass to support increasing aquaculture demand. This review investigates research and production of Artemia using agricultural waste. Various systems used for Artemia production in inoculated ponds are analysed and discussed to provide options for environmentally sustainable food systems that can be applied from either an artisanal level in developing countries with a considerable labour force, or in intensive systems in countries with large volumes of under-utilised resources, for example, sugar/alcohol-based waste and inland saline areas. Using agricultural waste, single cell protein production in a separate aerobic digester can be a simple, continuous food source for Artemia to enable daily biomass harvest. This could then be used as a fishmeal replacement or possibly for human consumption to promote a circular economy by remediating waste to produce protein, like a food production mine.

DOI 10.1111/raq.12784
Citations Scopus - 3Web of Science - 1
Co-authors Nepheronia Ogburn Uon, Megh Mallavarapu, Suresh Subashchandrabose
2023 Unnithan A, Bekele DN, Chadalavada S, Naidu R, 'Two-dimensional chlorinated vapour intrusion model involving advective transport of vapours with a highly permeable granular layer in the vadose zone serving as the preferential pathway.', Sci Total Environ, 869 161743 (2023) [C1]
DOI 10.1016/j.scitotenv.2023.161743
Co-authors Dawit Bekele, Sreenivasulu Chadalavada
2023 Bagherifam S, Brown TC, Naidu R, van Hullebusch ED, 'The effects of exogenous organic matter addition on bioaccessibility, adsorption kinetics and fractionation of antimony in soils', Water, Air, and Soil Pollution, 234 (2023) [C1]

Organic matter (OM) plays a pivotal role in adsorptive behavior, speciation, and bioavailability of nutrients and metal(loids) in soils. However, the effects of OM on adsorption, ... [more]

Organic matter (OM) plays a pivotal role in adsorptive behavior, speciation, and bioavailability of nutrients and metal(loids) in soils. However, the effects of OM on adsorption, fractionation, and bioavailability of antimony (Sb) in soils is largely unknown. In this study, the effects of two types of exogenous OM, including humic acid (HA) and fulvic acid (FA), on Sb bioavailability were compared in soils spiked with 1000 mg Sb kg-1 and incubated for 3 months under constant conditions. Treated soils were then subjected to single and sequential extractions using a Simplified Bioaccessibility Extraction Test (SBET) and BCR fractionation method as well as kinetic and desorption tests. Furthermore, SEM-EDX elemental maps of antimony were studies to better understand the distribution of antimony and its associations with soil elements. The kinetic data for amended and unamended soils fitted well with the pseudo-second order model, demonstrating that chemisorption might be the rate determining step. Bioaccessibility of antimony increased up to 65% in HA soils and OM additions increased acid-soluble fraction of Sb by approximately 40% (HA) and 75% (FA), compared to the control soils. OM amendments remarkably increased desorption of Sb from soils, whereas the maximum uptake capacity of Sb reduced in OM treated soils. The residual fraction accounted for 92% of total Sb in experimental soils, which was shifted to more labile fractions after OM amendments. The results of this research revealed that OM addition can greatly affect the bioaccessibility, distribution pattern and adsorption of Sb in Sb-impacted soils. Graphical abstract: [Figure not available: see fulltext.]

DOI 10.1007/s11270-023-06607-y
2023 Umeh AC, Hassan M, Egbuatu M, Zeng Z, Al Amin M, Samarasinghe C, Naidu R, 'Multicomponent PFAS sorption and desorption in common commercial adsorbents: Kinetics, isotherm, adsorbent dose, pH, and index ion and ionic strength effects.', Sci Total Environ, 904 166568 (2023) [C1]
DOI 10.1016/j.scitotenv.2023.166568
Citations Scopus - 5Web of Science - 4
Co-authors Anthony Umeh
2023 Fang C, Luo Y, Naidu R, 'Raman imaging for the analysis of silicone microplastics and nanoplastics released from a kitchen sealant', FRONTIERS IN CHEMISTRY, 11 (2023) [C1]
DOI 10.3389/fchem.2023.1165523
Co-authors Cheng Fang
2023 Fang C, Luo Y, Chuah C, Naidu R, 'Identification of microplastic fibres released from COVID-19 test swabs with Raman imaging', ENVIRONMENTAL SCIENCES EUROPE, 35 (2023) [C1]
DOI 10.1186/s12302-023-00737-0
Citations Scopus - 7
Co-authors Cheng Fang
2023 Rahman MM, Rinklebe J, Naidu R, 'Arsenic speciation as well as toxic and nutrient elements in pantavat (overnight steeped rice).', Environ Pollut, 331 121901 (2023) [C1]
DOI 10.1016/j.envpol.2023.121901
Co-authors Mahmud Rahman
2023 Luo Y, Naidu R, Fang C, 'Raman imaging to capture microplastics and nanoplastics carried by smartphones.', Sci Total Environ, 864 160959 (2023) [C1]
DOI 10.1016/j.scitotenv.2022.160959
Citations Scopus - 5
Co-authors Cheng Fang
2023 Luo Y, Awoyemi OS, Gopalan S, Nolan A, Robinson F, Fenstermacher J, et al., 'Investigating the effect of polarity reversal of the applied current on electrochemical degradation of per-and polyfluoroalkyl substances', Journal of Cleaner Production, 433 139691-139691 (2023) [C1]
DOI 10.1016/j.jclepro.2023.139691
Co-authors Megh Mallavarapu, Saianand Gopalan, Cheng Fang
2022 Natasha, Bibi I, Niazi NK, Shahid M, Ali F, Masood ul Hasan I, et al., 'Distribution and ecological risk assessment of trace elements in the paddy soil-rice ecosystem of Punjab, Pakistan', Environmental Pollution, 307 (2022) [C1]

Trace elements (TEs) contamination of agricultural soils requires suitable criteria for regulating their toxicity limits in soil and food crops, which depends on their potential e... [more]

Trace elements (TEs) contamination of agricultural soils requires suitable criteria for regulating their toxicity limits in soil and food crops, which depends on their potential ecological risk spanning regional to global scales. However, no comprehensive study is available that links TE concentrations in paddy soil with ecological and human health risks in less developed regions like Pakistan. Here we evaluated the data set to establish standard guidelines for defining the hazard levels of various potentially toxic TEs (such as As, Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, Se, Zn) in agricultural paddy soils of Punjab, Pakistan. In total, 100 topsoils (at 0¿15 cm depth) and 204 rice plant (shoot and grain) samples were collected from five ecological zones of Punjab (Gujranwala, Hafizabad, Vehari, Mailsi, and Burewala), representing the major rice growing regions in Pakistan. The degree of contamination (Cd) and potential ecological risk index (PERI) established from ecological risk models were substantially higher in 100% and 97% of samples, respectively. The positive matrix factorization (PMF) model revealed that the elevated TEs concentration, notably Cd, As, Cr, Ni, and Pb, in the agricultural paddy soil was attributed to the anthropogenic activities and groundwater irrigation. Moreover, the concentration of these TEs in rice grains was higher than the FAO/WHO's safe limits. This study provided a baseline, albeit critical knowledge, on the impact of TE-allied ecological and human health risks in the paddy soil-rice system in Pakistan; and it opens new avenues for setting TEs guidelines in agro-ecological zones globally, especially in underdeveloped regions.

DOI 10.1016/j.envpol.2022.119492
Citations Scopus - 25Web of Science - 16
Co-authors Mahmud Rahman
2022 Xue Y, Wang Z, Naidu R, Bush R, Yang F, Liu J, Huang M, 'Role of halide ions on organic pollutants degradation by peroxygens-based advanced oxidation processes: A critical review', Chemical Engineering Journal, 433 (2022) [C1]

Halide ions are common in wastewater but their roles in advanced oxidation processes (AOPs) and the degradation of pollutants are reportedly highly variable. This review seeks to ... [more]

Halide ions are common in wastewater but their roles in advanced oxidation processes (AOPs) and the degradation of pollutants are reportedly highly variable. This review seeks to reconcile conflicting data on the degradation of pollutants in the presence of halides by peroxygens-based AOPs reported in the literatures: peroxymonosulfate (PMS)-, peroxydisulfate (PDS)-, and hydrogen peroxide (H2O2)-based AOPs, and electrochemical advanced oxidation processes (EAOPs). Seven common substituent groups on the aromatic ring (i.e., hydroxy groups (¿OH), amino groups (¿NH2), alkyl groups (¿R), olefinic compounds, carboxyl groups(¿COOH), nitro groups (¿NO2), halogens (¿X)) are considered, and halide ions were found to affect contaminants¿ degradation in all cases, either negatively or positively. The key influencing factors such as substrate properties and operating parameters (e.g., halides dosage, ionic strength, pH, and activation method) are examined. Each individual variable may affect degradation rates, but many of these effects are a combination of these variables in experimental or natural systems. Thus, the research work on the effect of halides on the simultaneous removal of more organics is needed. This present study details the unresolved challenges to provide a path for engineering challenges on AOPs. According to the factors affecting the performance of halides during decontamination processes, better AOP technologies should be selected to diminish adverse effects and take advantage of positive effects to deal with target pollutants in the saline environment, so as to achieve the purpose of reducing the operating costs and emission reduction.

DOI 10.1016/j.cej.2022.134546
Citations Scopus - 30Web of Science - 10
Co-authors Zhaohui Wang
2022 Khan AUH, Naidu R, Dharmarajan R, Fang C, Shon H, Dong Z, Liu Y, 'The interaction mechanisms of co-existing polybrominated diphenyl ethers and engineered nanoparticles in environmental waters: A critical review', JOURNAL OF ENVIRONMENTAL SCIENCES, 124 227-252 (2022) [C1]
DOI 10.1016/j.jes.2021.10.018
Citations Scopus - 13Web of Science - 3
Co-authors Cheng Fang, Yanju Liu
2022 Asadi P, Alaie E, Heidari A, Naidu R, 'Photodegradation of modified petroleum impregnated bentonite mulch under the effects of solar radiation simulating the outdoor condition.', Environ Sci Pollut Res Int, 29 14754-14766 (2022) [C1]
DOI 10.1007/s11356-021-16714-0
2022 Dadkhah-Aghdash H, Zare-Maivan H, Heydari M, Sharifi M, Lucas-Borja ME, Naidu R, 'Air pollution from gas refinery through contamination with various elements disrupts semiarid Zagros oak (Quercus brantii Lindl.) forests, Iran.', Sci Rep, 12 284 (2022) [C1]
DOI 10.1038/s41598-021-04429-8
Citations Scopus - 3
2022 Kulathunga MRDL, Wijayawardena MAA, Naidu R, 'Dietary heavy metal(loid)s exposure and prevalence of chronic kidney disease of unknown aetiology (CKDu) in Sri Lanka', ENVIRONMENTAL GEOCHEMISTRY AND HEALTH, 44 3863-3874 (2022) [C1]
DOI 10.1007/s10653-021-01144-1
Citations Scopus - 3Web of Science - 3
Co-authors Ayanka Wijayawardena
2022 Luo Y, Zhang X, Zhang Z, Naidu R, Fang C, 'Dual-Principal Component Analysis of the Raman Spectrum Matrix to Automatically Identify and Visualize Microplastics and Nanoplastics', ANALYTICAL CHEMISTRY, 94 3150-3157 (2022) [C1]
DOI 10.1021/acs.analchem.1c04498
Citations Scopus - 29Web of Science - 7
Co-authors Cheng Fang
2022 Luo Y, Zhang Z, Naidu R, Zhang X, Fang C, 'Raman imaging of microplastics and nanoplastics released from the printed toner powders burned by a mimicked bushfire', Science of the Total Environment, 849 (2022) [C1]

Plastic contamination is a growing global concern, but the characterisation approaches for microplastics are limited so far, and even more lacking for nanoplastics. As another pub... [more]

Plastic contamination is a growing global concern, but the characterisation approaches for microplastics are limited so far, and even more lacking for nanoplastics. As another public concern, bushfire has the potential to exacerbate the negative ecological effects of plastic waste. We thus study the release of microplastics and nanoplastics from toner powers printed on a paper sheet following a mimicked bushfire. The results show that, along the fire frontier, there is a charred area first, then a cindered area towards mineralisation via a full combustion. We find that, depending on the extent of burning, the printed toner powers containing microplastics can melt to aggregate, or crack to break down to nanoplastics, which are well characterised by mass spectrometry and Raman imaging combined with algorithms. Overall, the results shed new light on the microplastics and nanoplastics once affected by bushfire.

DOI 10.1016/j.scitotenv.2022.157686
Citations Scopus - 4Web of Science - 1
Co-authors Cheng Fang
2022 Luo Y, Gibson CT, Chuah C, Tang Y, Naidu R, Fang C, 'Raman imaging for the identification of Teflon microplastics and nanoplastics released from non-stick cookware.', Science of the Total Environment, 851 (2022) [C1]
DOI 10.1016/j.scitotenv.2022.158293
Citations Scopus - 14Web of Science - 7
Co-authors Cheng Fang
2022 Luo Y, Al Amin M, Gibson CT, Chuah C, Tang Y, Naidu R, Fang C, 'Raman imaging of microplastics and nanoplastics generated by cutting PVC pipe', ENVIRONMENTAL POLLUTION, 298 (2022) [C1]
DOI 10.1016/j.envpol.2022.118857
Citations Scopus - 17Web of Science - 4
Co-authors Cheng Fang
2022 Luo Y, Gibson CT, Chuah C, Tang Y, Ruan Y, Naidu R, Fang C, 'Fire releases micro- and nanoplastics: Raman imaging on burned disposable gloves', Environmental Pollution, 312 (2022) [C1]
DOI 10.1016/j.envpol.2022.120073
Citations Scopus - 5Web of Science - 2
Co-authors Cheng Fang
2022 Luo Y, Gibson CT, Chuah C, Tang Y, Naidu R, Fang C, 'Applying Raman imaging to capture and identify microplastics and nanoplastics in the garden', JOURNAL OF HAZARDOUS MATERIALS, 426 (2022) [C1]
DOI 10.1016/j.jhazmat.2021.127788
Citations Scopus - 12Web of Science - 7
Co-authors Cheng Fang
2022 Luo Y, Chuah C, Al Amin M, Khoshyan A, Gibson CT, Tang Y, et al., 'Assessment of microplastics and nanoplastics released from a chopping board using Raman imaging in combination with three algorithms', JOURNAL OF HAZARDOUS MATERIALS, 431 (2022) [C1]
DOI 10.1016/j.jhazmat.2022.128636
Citations Scopus - 12Web of Science - 7
Co-authors Cheng Fang
2022 Luo Y, Naidu R, Zhang X, Fang C, 'Microplastics and nanoplastics released from a PPE mask under a simulated bushfire condition', Journal of Hazardous Materials, 439 (2022) [C1]

Due to COVID-19, large amounts of personal protective equipment (PPE) have been used, and many PPE units are made of plastics, such as face masks. The masks can be burned naturall... [more]

Due to COVID-19, large amounts of personal protective equipment (PPE) have been used, and many PPE units are made of plastics, such as face masks. The masks can be burned naturally in a bushfire or artificially at the incineration plants, and release microplastics and nanoplastics from the mask plastic fibres. A fire can cause the plastic, such as polypropylene (PP) fibres, to be molten and stick to the solid surface, such as glass, soil, concrete or plant, as films or islands, due to the binding property of the molten plastic material. Once the films or islands are peeled off in the processes such as weathering, ageing, or treatment and clean-up, there are residuals leftover, which are identified as nanoplastics and microplastics via Raman imaging, with the significant release amount of ~1100 nanoplastics / 10 µm2 or ~11 billion / cm2, and ~50 microplastics / 420 µm2 or ~12 million / cm2. Moreover, surface group is deviated on the plastic surface, which can also be distinguished and visualised as well via Raman imaging, down to nano size. This test validates the Raman imaging approach to capture microplastics and nanoplastics, and also provides important information about the fate and transportation of PPE mask in the environment, particularly when subjected to a fire. Overall, Raman imaging can be an effective option to characterise the microplastics and nanoplastics, along with the deviated surface group.

DOI 10.1016/j.jhazmat.2022.129621
Citations Scopus - 12Web of Science - 1
Co-authors Cheng Fang
2022 Sobhani Z, Luo Y, Gibson CT, Tang Y, Naidu R, Fang C, 'Collecting microplastics in gardens: Case study (ii) from ropes', ENVIRONMENTAL TECHNOLOGY & INNOVATION, 26 (2022) [C1]
DOI 10.1016/j.eti.2022.102322
Citations Scopus - 2Web of Science - 2
Co-authors Cheng Fang, Zahra Sobhani
2022 Campbell J, Clewell H, Cox T, Dourson M, Ethridge S, Forsberg N, et al., 'The Conundrum of the PFOA human half-life, an international collaboration', Regulatory Toxicology and Pharmacology, 132 (2022) [C1]

The Steering Committee of the Alliance for Risk Assessment (ARA) opened a call for scientists interested in resolving what appeared to be a conundrum in estimating of the half-lif... [more]

The Steering Committee of the Alliance for Risk Assessment (ARA) opened a call for scientists interested in resolving what appeared to be a conundrum in estimating of the half-life of perfluorooctanoate (PFOA) in humans. An Advisory Committee was formed from nominations received and a subsequent invitation led to the development of three small independent working groups to review appropriate information and attempt a resolution. Initial findings were shared among these groups and a conclusion developed from the ensuing discussions. Many human observational studies have estimated the PFOA half-life. Most of these studies note the likely occurrence of unmonitored PFOA exposures, which could inflate values of the estimated PFOA half-life. Also, few of these studies estimated the half-life of PFOA isomers, the branched chains of which likely have shorter half-lives. This could deflate values of the estimated linear PFOA half-life. Fortunately, several studies informed both of these potential problems. The majority opinion of this international collaboration is that the studies striking the best balance in addressing some of these uncertainties indicate the likely central tendency of the human PFOA half-life is less than 2 years. The single best value appears to be the geometric mean (GM) of 1.3 years (Zhang et al., 2013, Table 3), based on a GM = 1.7 years in young females (n = 20) and GM = 1.2 years in males of all ages and older females (n = 66). However, a combined median value from Zhang et al. (2013) of 1.8 years also adds value to this range of central tendency. While the Collaboration found this study to be the least encumbered with unmonitored PFOA exposures and branched isomers, more studies of similar design would be valuable. Also valuable would be clarification around background exposures in other existing studies in case adjustments to half-life estimates are attempted.

DOI 10.1016/j.yrtph.2022.105185
Citations Scopus - 8Web of Science - 7
2022 Fan X, Tang S, Wang Y, Fan W, Ben Y, Naidu R, Dong Z, 'Global Exposure to Per- and Polyfluoroalkyl Substances and Associated Burden of Low Birthweight.', Environ Sci Technol, 56 4282-4294 (2022) [C1]
DOI 10.1021/acs.est.1c08669
Citations Scopus - 18Web of Science - 5
2022 Campbell J, Clewell H, Cox T, Dourson M, Ethridge S, Forsberg N, et al., 'Response to letter to editor "letter to the editors regarding "the Conundrum of the PFOA human half-life, an international collaboration"', REGULATORY TOXICOLOGY AND PHARMACOLOGY, 134 (2022)
DOI 10.1016/j.yrtph.2022.105246
Citations Scopus - 1
2022 Deb AK, Biswas B, Naidu R, Rahman MM, 'Mechanistic insights of hexavalent chromium remediation by halloysite-supported copper nanoclusters', Journal of Hazardous Materials, 421 (2022) [C1]

Chromium (Cr) pollution is a significant environmental concern with remediation challenge. Hexavalent chromium (Cr(VI)) is more toxic than trivalent chromium (Cr(III)) due to its ... [more]

Chromium (Cr) pollution is a significant environmental concern with remediation challenge. Hexavalent chromium (Cr(VI)) is more toxic than trivalent chromium (Cr(III)) due to its mutagenicity and oncogenicity. In this investigation, a multi-functional material, copper nanoclusters (CuNCs)-halloysite nanotubes (HNT) composite (CuNCs@HNT), has been synthesised in an eco-friendly manner and utilised for Cr(VI) remediation. Advanced analytical tools confirmed the seeding of ultra-fine CuNCs onto HNT surfaces. The maximum adsorption capacity of CuNCs@HNT is 79.14 ± 6.99 mg/g at pH 5 ± 0.1 with an increment at lower pHs. This performance was comparable for real surface stream water as well as other reported materials. The pseudo-second-order kinetic-, intra-particle diffusion- and Freundlich isotherm models well fit the experimental data implying that the chemisorption, multiphase diffusion and multi-molecular layer distribution occurred during adsorption. The Fourier-transform infrared and the x-ray photoelectron spectra also ensured the transformation of Cr(VI) to Cr(III) indicating the material's suitability for concurrent adsorption and reduction of Cr(VI). While coexisting cations and anions did not overwhelm this adsorption, CuNCs@HNT was regenerated and reused five successive times in adsorption-desorption cycles without significant loss of adsorption capacity and material's integrity. Therefore, this multi-functional, biocompatible, low-cost and stable CuNCs@HNT composite may have practical application for similar toxic metals remediation.

DOI 10.1016/j.jhazmat.2021.126812
Citations Scopus - 18Web of Science - 11
Co-authors Mahmud Rahman, Bhaba Biswas
2022 Kulathunga MRDL, Wijayawardena MAA, Naidu R, Wimalawansa SJ, Rahman MM, 'Health risk assessment from heavy metals derived from drinking water and rice, and correlation with CKDu', Frontiers in Water, 3 (2022) [C1]
DOI 10.3389/frwa.2021.786487
Citations Scopus - 4
Co-authors Mahmud Rahman, Ayanka Wijayawardena
2022 Logeshwaran P, Subashchandrabose SR, Krishnan K, Sivaram AK, Annamalai P, Naidu R, Megharaj M, 'Polycyclic aromatic hydrocarbons biodegradation by fenamiphos degrading Microbacterium esteraromaticum MM1', Environmental Technology and Innovation, 27 (2022) [C1]

A Gram-positive bacterium, Microbacterium esteraromaticum MM1 able to degrade organophosphorus pesticides such as fenamiphos and malathion, also possessed the ability to degrade h... [more]

A Gram-positive bacterium, Microbacterium esteraromaticum MM1 able to degrade organophosphorus pesticides such as fenamiphos and malathion, also possessed the ability to degrade high molecular weight polycyclic aromatic hydrocarbon (PAH), pyrene (Pyr) and benzo[a]pyrene (BaP). The strain MM1 degraded 98.7% of initially spiked 100 mg L-1 pyrene within 15 days from the M9 mineral salts medium (pH 7.0) with 0.1% glucose. At optimal pH 7.0, 57.81% of pyrene (100 mg L-1) was degraded as the sole carbon source. In order to determine the influence of carbon sources (glucose, sodium acetate, sodium succinate) and PAHs (Naphthalene (Nap), Phenanthrene (Phe), Benzo[a]pyrene (BaP)) on pyrene degradation, a full factorial design analysis was conducted. Among the carbon sources examined, glucose, sodium acetate, and all the PAHs positively affected pyrene degradation. Interestingly, in the presence of other PAHs, benzo[a]pyrene was degraded by MM1 but not as the sole carbon source. Crude enzyme extracted from MM1 degraded pyrene with the Km and Vmax values of 49.3 µg ml-1 (equivalent to 250 µM) and 9.5 µg ml-1 min-1 mg-1 of crude protein (equivalent to 50 µM), respectively with a specific activity of 0.19 µg ml-1 mg-1 of crude protein. Metabolites such as monohydroxypyrene, 2,6-di-isopropylnaphthalene, and phthalic acid were identified during pyrene degradation by MM1. Differential expression of the protein in the presence of pyrene resulted in the inducement of enolase (phosphopyruvate hydratase) and pyridine nucleotide-disulphide oxidoreductase in MM1. To the best of our knowledge, this is the first report on the degradation of pyrene by M. esteraromaticum MM1.

DOI 10.1016/j.eti.2022.102465
Citations Scopus - 5
Co-authors Megh Mallavarapu, Suresh Subashchandrabose, Logeshwaran Panneerselvan
2022 Zhang D, Yan K, Liu Y, Naidu R, 'Effects of Phosphate, Red Mud, and Biochar on As, Cd, and Cu Immobilization and Enzymatic Activity in a Co-Contaminated Soil', PROCESSES, 10 (2022) [C1]
DOI 10.3390/pr10061127
Citations Scopus - 4
Co-authors Yanju Liu
2022 Perera IA, Abinandan S, Panneerselvan L, Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Co-culturing of microalgae and bacteria in real wastewaters alters indigenous bacterial communities enhancing effluent bioremediation', ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS, 64 (2022) [C1]
DOI 10.1016/j.algal.2022.102705
Citations Scopus - 20Web of Science - 6
Co-authors Suresh Subashchandrabose, Abinandan Sudharsanam, Megh Mallavarapu, Logeshwaran Panneerselvan
2022 Rusmin R, Sarkar B, Mukhopadhyay R, Tsuzuki T, Liu Y, Naidu R, 'Facile one pot preparation of magnetic chitosan-palygorskite nanocomposite for efficient removal of lead from water', JOURNAL OF COLLOID AND INTERFACE SCIENCE, 608 575-587 (2022) [C1]
DOI 10.1016/j.jcis.2021.09.109
Citations Scopus - 26Web of Science - 12
Co-authors Yanju Liu
2022 Gao Y, Yuan L, Du J, Wang H, Yang X, Duan L, et al., 'Bacterial community profile of the crude oil-contaminated saline soil in the Yellow River Delta Natural Reserve, China', Chemosphere, 289 (2022) [C1]

Crude oil contamination greatly influence soil bacterial community. Proliferative microbes in the crude oil-contaminated soil are closely related to the living conditions. Oil wel... [more]

Crude oil contamination greatly influence soil bacterial community. Proliferative microbes in the crude oil-contaminated soil are closely related to the living conditions. Oil wells in the Yellow River Delta Natural Reserve (YRDNR) region is an ideal site for investigating the bacterial community of crude oil-contaminated saline soil. In the present study, 18 soil samples were collected from the depths of 0¿20 cm and 20¿40 cm around the oil wells in the YRDNR. The bacterial community profile was analyzed through high-throughput sequencing to trace the oil-degrading aerobic and anaerobic bacteria. The results indicated that C15¿C28 and C29¿C38 were the main fractions of total petroleum hydrocarbon (TPH) in the sampled soil. These TPH fractions had a significant negative effect on bacterial biodiversity (Shannon, Simpson, and Chao1 indices), which led to the proliferation of hydrocarbon-degrading bacteria. A comprehensive analysis between the environmental factors and soil microbial community structure showed that Streptococcus, Bacillus, Sphingomonas, and Arthrobacter were the aerobic hydrocarbon-degrading bacteria; unidentified Rhodobacteraceae and Porticoccus were considered to be the possible facultative anaerobic bacteria with hydrocarbon biodegradation ability; Acidithiobacillus, SAR324 clade, and Nitrosarchaeum were predicted to be the anaerobic hydrocarbon-degrading bacteria in the sub-surface soil. Furthermore, large amount of carbon sources derived from TPH was found to cause depletion of bioavailable nitrogen in the soil. The bacteria associated with nitrogen transformation, such as Solirubrobacter, Candidatus Udaeobacter, Lysinibacillus, Bradyrhizobium, Sphingomonas, Mycobacterium, and Acidithiobacillus, were highly abundant; these bacteria may possess the ability to increase nitrogen availability in the crude oil-contaminated soil. The bacterial community functions were significantly different between the surface and the sub-surface soil, and the dissolved oxygen concentration in soil was considered to be potential influencing factor. Our results could provide useful information for the bioremediation of crude oil-contaminated saline soil.

DOI 10.1016/j.chemosphere.2021.133207
Citations Scopus - 19Web of Science - 7
Co-authors Mezbaul Bahar, Yanju Liu
2022 Siddique AB, Rahman MM, Islam MR, Naidu R, 'Influences of soil pH, iron application and rice variety on cadmium distribution in rice plant tissues', Science of the Total Environment, 810 (2022) [C1]

Cadmium (Cd) is a widespread environmental contaminant, and its increasing concentrations in rice poses significant risks to human health. Globally, rice is a staple food for mill... [more]

Cadmium (Cd) is a widespread environmental contaminant, and its increasing concentrations in rice poses significant risks to human health. Globally, rice is a staple food for millions of people, and consequently, effective strategies to reduce Cd accumulation in rice are needed. This study investigates the effect of soil pH (Soil 1: 4.6; Soil 2: 6.6) and iron (Fe) application (at 0, 1.0 and 2.0 g/kg) on Fe plaque formation, Cd sequestration in Fe plaques and Cd bioaccumulation in different parts of the rice plant for three different Cd-graded paddy soils (0, 1.0 and 3.0 mg/kg, respectively) using two Australian rice cultivars under glasshouse conditions. Results show that grain and straw yield declined as Cd toxicity increased, and the toxic effects of Cd were lower in the Quest cultivar than in the Langi cultivar. With applications of Cd at 1.0 mg/kg and 3.0 mg/kg, Cd concentrations in rice grown in Soil 1 were 1.09 mg/kg and 1.37 mg/kg, respectively, while those in rice grown in Soil 2 were 0.38 mg/kg and 0.52 mg/kg, respectively. Soil pH significantly affected the bioaccumulation of Cd in different parts of the rice plant. At both levels of Cd application, Cd concentration was highest in the root, followed by the stem, leaf, husk and grain. Cd was more concentrated in Fe plaques formed by the application of Fe than in rice plant tissues. The Quest cultivar had a higher ability to produce Fe plaques and a 1.3- and 1.4-times higher Cd concentration compared with the Langi cultivar in Soils 1 and 2, respectively.

DOI 10.1016/j.scitotenv.2021.152296
Citations Scopus - 20Web of Science - 7
Co-authors Mahmud Rahman
2022 Luo Y, Sobhani Z, Zhang Z, Zhang X, Gibson CT, Naidu R, Fang C, 'Raman imaging and MALDI-MS towards identification of microplastics generated when using stationery markers', Journal of Hazardous Materials, 424 (2022) [C1]

The characterisation of microplastics is still a challenge, particularly when the sample is a mixture with a complex background, such as an ink mark on paper. To address this chal... [more]

The characterisation of microplastics is still a challenge, particularly when the sample is a mixture with a complex background, such as an ink mark on paper. To address this challenge, we developed and compared two approaches, (i) Raman imaging, combined with logic-based and principal component analysis (PCA)-based algorithms, and (ii) matrix-assisted laser desorption/ionisation-mass spectrometry (MALDI-MS). We found that, accordingly, (i) if the Raman signal of plastics is identifiable and not completely shielded by the background, Raman imaging can extract the plastic signals and visualise their distribution directly, with the help of a logic-based or PCA-based algorithm, via the ¿fingerprint¿ spectrum; (ii) when the Raman signal is shielded and masked by the background, MALDI-MS can effectively capture and identify the plastic polymer, via the ¿barcode¿ of the mass spectrum linked with the monomer. Overall, both Raman imaging and MALDI-MS have benefits and limitations for microplastic analysis; if accessible, the combined use of these two techniques is generally recommended, especially when assessing samples with strong background interference.

DOI 10.1016/j.jhazmat.2021.127478
Citations Scopus - 13Web of Science - 9
Co-authors Cheng Fang, Zahra Sobhani
2022 Shehzad MT, Sabir M, Saifullah, Siddique AB, Rahman MM, Naidu R, 'Impact of Water Regimes on Minimizing the Accumulation of Arsenic in Rice (Oryza sativa L.)', WATER AIR AND SOIL POLLUTION, 233 (2022) [C1]
DOI 10.1007/s11270-022-05856-7
Citations Scopus - 2
Co-authors Mahmud Rahman
2022 Nuruzzaman M, Liu Y, Ren J, Rahman M, Zhang H, Johir MAH, et al., 'Capability of Organically Modified Montmorillonite Nanoclay as a Carrier for Imidacloprid Delivery', ACS Agricultural Science & Technology, 2 57-68 (2022) [C1]
DOI 10.1021/acsagscitech.1c00125
Citations Scopus - 6Web of Science - 2
Co-authors Mahmud Rahman, Md Nuruzzaman, Yanju Liu
2022 Perera IA, Abinandan S, Subashchandrabose SR, Venkateswarlu K, Cole N, Naidu R, Megharaj M, 'Extracellular Polymeric Substances Drive Symbiotic Interactions in Bacterial Microalgal Consortia.', Microb Ecol, 83 596-607 (2022) [C1]
DOI 10.1007/s00248-021-01772-1
Citations Scopus - 21Web of Science - 13
Co-authors Abinandan Sudharsanam, Suresh Subashchandrabose, Megh Mallavarapu
2022 Wijayawardena M, Kulathunga MRDL, Naidu R, Wimalawansa SJ, 'Potential Link between Spatial Variation and Translocation characteristics of Heavy Metals in Paddy topsoil and Human health risks in a CKDu prevalent area of Sri Lanka', Weeds: Journal of the APWSS, 4 62-75 (2022) [C1]
Co-authors Ayanka Wijayawardena
2022 Haque S, Srivastava N, Pal DB, Alkhanani MF, Almalki AH, Areeshi MY, et al., 'Functional microbiome strategies for the bioremediation of petroleum-hydrocarbon and heavy metal contaminated soils: A review', SCIENCE OF THE TOTAL ENVIRONMENT, 833 (2022) [C1]
DOI 10.1016/j.scitotenv.2022.155222
Citations Scopus - 22Web of Science - 6
2022 Shehzad MT, Sabir M, Zia-Ur-Rehman M, Zia MA, Naidu R, 'Arsenic concentrations in soil, water, and rice grains of rice-growing areas of Punjab, Pakistan: multivariate statistical analysis.', Environmental monitoring and assessment, 194 346 (2022) [C1]
DOI 10.1007/s10661-022-10001-2
Citations Scopus - 8Web of Science - 1
2022 Hamid Y, Liu L, Usman M, Naidu R, Haris M, Lin Q, et al., 'Functionalized biochars: Synthesis, characterization, and applications for removing trace elements from water.', Journal of hazardous materials, 437 129337 (2022) [C1]
DOI 10.1016/j.jhazmat.2022.129337
Citations Scopus - 20Web of Science - 2
2022 Perera IA, Abinandan S, Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Combined inorganic nitrogen sources influence the release of extracellular compounds that drive mutualistic interactions in microalgal-bacterial co-cultures', JOURNAL OF APPLIED PHYCOLOGY, 34 1311-1322 (2022) [C1]
DOI 10.1007/s10811-022-02711-4
Citations Scopus - 3Web of Science - 1
Co-authors Megh Mallavarapu, Abinandan Sudharsanam, Suresh Subashchandrabose
2022 Hai NNS, Sanderson P, Qi F, Du J, Nong NN, Bolan N, Naidu R, 'Effects of chelates (EDTA, EDDS, NTA) on phytoavailability of heavy metals (As, Cd, Cu, Pb, Zn) using ryegrass (Lolium multiflorum Lam.).', Environmental science and pollution research international, 29 42102-42116 (2022) [C1]
DOI 10.1007/s11356-022-19877-6
Citations Scopus - 4Web of Science - 4
Co-authors Nanthi Bolan
2022 Grieco SA, Koenigsberg S, Claffey J, Cooper I, Dewitt A, Naidu R, Wymore R, 'Ex situ treatment and residual management of PFAS contaminated environmental media', REMEDIATION-THE JOURNAL OF ENVIRONMENTAL CLEANUP COSTS TECHNOLOGIES & TECHNIQUES, 32 55-63 (2022) [C1]
DOI 10.1002/rem.21704
Citations Scopus - 4Web of Science - 2
2022 Heikal YM, El-Esawi MA, Naidu R, Elshamy MM, 'Eco-biochemical responses, phytoremediation potential and molecular genetic analysis of Alhagi maurorum grown in metal-contaminated soils.', BMC plant biology, 22 383 (2022) [C1]
DOI 10.1186/s12870-022-03768-6
Citations Scopus - 4Web of Science - 2
2022 Saianand G, Gopalan A-I, Wanga L, Venkatramanan K, Roy VAL, Sonar P, et al., 'Conducting polymer based visible light photocatalytic composites for pollutant removal: Progress and prospects', ENVIRONMENTAL TECHNOLOGY & INNOVATION, 28 (2022) [C1]
DOI 10.1016/j.eti.2022.102698
Citations Scopus - 15
Co-authors Liang Wang, Saianand Gopalan
2022 Perera IA, Abinandan S, Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Impact of Nitrate and Ammonium Concentrations on Co-Culturing of Tetradesmus obliquus IS2 with Variovorax paradoxus IS1 as Revealed by Phenotypic Responses', MICROBIAL ECOLOGY, 83 951-959 (2022) [C1]
DOI 10.1007/s00248-021-01832-6
Citations Scopus - 4Web of Science - 4
Co-authors Abinandan Sudharsanam, Megh Mallavarapu, Suresh Subashchandrabose
2022 Cheng F, Luo Y, Naidu R, 'Raman imaging combined with an improved PCA/algebra-based algorithm to capture microplastics and nanoplastics', ANALYST, 147 4301-4311 (2022) [C1]
DOI 10.1039/d2an00761d
Citations Scopus - 7
2022 Islam MR, Sanderson P, Payne TE, Deb AK, Naidu R, 'Role of beryllium in the environment: Insights from specific sorption and precipitation studies under different conditions.', The Science of the total environment, 838 155698 (2022) [C1]
DOI 10.1016/j.scitotenv.2022.155698
Citations Scopus - 4Web of Science - 1
Co-authors Mdrashidul Islam
2022 Mehmood K, Bao Y, Saifullah W, Cheng W, Khan MA, Siddique N, et al., 'Predicting the quality of air with machine learning approaches: Current research priorities and future perspectives', JOURNAL OF CLEANER PRODUCTION, 379 (2022) [C1]
DOI 10.1016/j.jclepro.2022.134656
Citations Scopus - 11
2022 Bagherifam S, Brown TC, Fellows CM, Naidu R, Komarneni S, 'In situ stabilization of arsenic in soil with organoclay, organozeolite, birnessite, goethite and lanthanum-doped magnetic biochar', PEDOSPHERE, 32 764-776 (2022) [C1]
DOI 10.1016/j.pedsph.2022.06.008
Citations Scopus - 6Web of Science - 1
2022 Bashir S, Awan MS, Farrukh MA, Naidu R, Khan SA, Rafique N, et al., 'In-vivo (
DOI 10.2147/ijn.s372343
Citations Scopus - 2
2022 Rashid MH, Rahman MM, Naidu R, 'Zinc Biofortification through Basal Zinc Supply Reduces Grain Cadmium in Mung Beans: Metal Partitioning and Health Risks Assessment.', Toxics, 10 689 (2022) [C1]
DOI 10.3390/toxics10110689
Co-authors Mahmud Rahman
2022 Luo Y, Gibson CT, Tang Y, Naidu R, Fang C, 'Characterising microplastics in shower wastewater with Raman imaging', Science of the Total Environment, 811 (2022) [C1]

Microplastics can potentially be released in our daily activities, such as via our showers, as our clothes are made of plastic fibres, and/or cotton fibres. The challenge is how t... [more]

Microplastics can potentially be released in our daily activities, such as via our showers, as our clothes are made of plastic fibres, and/or cotton fibres. The challenge is how to characterise these microplastics in shower debris. Herewith we employ Raman imaging to directly visualise the microplastics collected from shower wastewater. Raman can map an image from the scanning array that contains a matrix of thousands of spectra, featuring a considerably higher signal-noise ratio than that from a single spectrum. The increased signal-noise ratio reduces the complexity of sample preparation. Consequently, after the shower debris was sampled and washed, Raman imaging allowed us to distinguish the microplastic fibres from the background including cotton fibres and dirt aggregates. Interestingly, by adjusting the laser power intensity, the scanning process enabled simultaneous in-situ bleaching of the colorants formulated in the textile fibres and collection of signals. The disadvantage of Raman imaging such as the short focusing/working distance is also presented and discussed. Overall, the Raman imaging can extract meaningful information from the complex shower debris samples to enable analysis of microplastics.

DOI 10.1016/j.scitotenv.2021.152409
Citations Scopus - 14Web of Science - 9
Co-authors Cheng Fang
2022 Nuruzzaman M, Liu Y, Ren J, Rahman M, Zhang H, Johir MAH, et al., 'Capability of Organically Modified Montmorillonite Nanoclay as a Carrier for Imidacloprid Delivery', ACS Agricultural Science & Technology, 2 57-68 (2022)
DOI 10.1021/acsagscitech.1c00125
Co-authors Yanju Liu, Md Nuruzzaman, Mahmud Rahman
2022 Deb AK, Biswas B, Rahman MM, Xi Y, Paul SK, Naidu R, 'Magnetite Nanoparticles Loaded into Halloysite Nanotubes for Arsenic(V) Removal from Water', ACS Applied Nano Materials, (2022) [C1]

Groundwater contaminated by arsenic (As) is a serious concern because it poses a significant threat to millions of people reliant on both drinking and irrigation of farms. Hence, ... [more]

Groundwater contaminated by arsenic (As) is a serious concern because it poses a significant threat to millions of people reliant on both drinking and irrigation of farms. Hence, the low-cost and efficient treatment of these waters is of utmost importance. This study presents the ecofriendly synthesis of magnetite nanoparticles (Fe3O4 NPs)-immobilized halloysite nanotube (HNT) composite (Fe3O4@HNT) for remediating arsenate [As(V)] from water. High-resolution transmission electron microscopy confirmed that ultrasmall Fe3O4 NPs (4.52 ± 1.63 nm) were immobilized on the interior surface of HNT. Fe3O4@HNT possesses a larger surface area (82 ± 0.23 m2/g) and a higher thermal stability (7.1% weight loss at 950 °C) than a pristine HNT (47.23 ± 0.14 m2/g and 12.6%, respectively). Adsorption kinetics were best fitted with pseudo-second-order and intraparticle diffusion, while the isotherms results were best supported with the Freundlich model (R2 = 0.99 in each case). Therefore, it could be surmised that multiphase rate-controlling chemisorption occurred during adsorption. The thermodynamics data revealed the endothermic nature of As(V) adsorption by Fe3O4@HNT. Fourier transform infrared and X-ray photelectron spectroscopy analyses confirmed chemical bonding between As and Fe. In addition, Fe3O4@HNT was easily separable by an external magnet (the saturation magnetization value was 20 emu/g), which is an additional benefit of the material to be used on an industrial scale. The material was also reusable after regeneration for five rounds of consecutive sorption-desorption with excellent efficiency and no substantial loss of structural integrity. Furthermore, Fe3O4@HNT removed more than 99% As(V) from the groundwater, signifying its viability in real-case implementation. Cost-benefit analysis ensured that Fe3O4@HNT was cost-effective, while its biocompatibility test confirmed no detrimental impact on soil bacterial growth once the spent material had been disposed. Consequently, cheap, easily separable, reusable, and biocompatible Fe3O4@HNT may be a prospective composite for the sustainable eradication of As and other metallic toxicants from wastewater.

DOI 10.1021/acsanm.2c00239
Citations Scopus - 12Web of Science - 2
Co-authors Bhaba Biswas, Mahmud Rahman
2022 Liu Y, Bahar MM, Samarasinghe SVAC, Qi F, Carles S, Richmond WR, et al., 'Ecological risk assessment for perfluorohexanesulfonic acid (PFHxS) in soil using species sensitivity distribution (SSD) approach', Journal of Hazardous Materials, 439 (2022) [C1]
DOI 10.1016/j.jhazmat.2022.129667
Citations Scopus - 4Web of Science - 1
Co-authors Mezbaul Bahar, Chamila Samarasinghe, Yanju Liu
2022 Hassan M, Naidu R, Du J, Qi F, Ahsan MA, Liu Y, 'Magnetic responsive mesoporous alginate/beta-cyclodextrin polymer beads enhance selectivity and adsorption of heavy metal ions', INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES, 207 826-840 (2022) [C1]
DOI 10.1016/j.ijbiomac.2022.03.159
Citations Scopus - 41Web of Science - 18
Co-authors Yanju Liu
2022 Li J, Wang X, Yang J, Liu Y, Naidu R, 'Predicting the thresholds of metals with limited toxicity data with invertebrates in standard soils using quantitative ion character-activity relationships (QICAR)', Journal of Hazardous Materials, 423 (2022) [C1]

Terrestrial invertebrates are often used as indicator organisms in ecological risk assessments. However, determining the risk of metals to invertebrates is laborious and time-cons... [more]

Terrestrial invertebrates are often used as indicator organisms in ecological risk assessments. However, determining the risk of metals to invertebrates is laborious and time-consuming due to the lengthy testing and ethical approval procedures. In this study, a review of the literature was conducted to provide toxicity data for two standard soils (OECD and LUFA 2.2). An attempt was made to establish models for predicting the toxicity of elements to invertebrates using quantitative ion character-activity relationships (QICARs). In OECD soil, the element toxicity of four groups (Enchytraeus albidus mortality and reproduction, Folsomia candida and Eisenia fetida reproduction) showed significant correlations with atomic number, atomic mass and atomic ionization potential (0.852 = R2 = 0.989, P < 0.05). For LUFA 2.2 soil, polarization force parameters and boiling point were most significant parameters for toxicity values of F. candida and Enchytraeus crypticus, respectively (0.866 = R2 = 0.962, P < 0.05). Finally, QICAR models were established, and LC50 or EC50 of elements were predicted. Then, models were verified using standard and natural soils, and showed that errors between observed and predicted logLC50/EC50 were mostly < 0.5 orders of magnitude. Thus, the developed QICAR models have potential for predicting the toxicity of elements for soils.

DOI 10.1016/j.jhazmat.2021.126982
Citations Scopus - 3Web of Science - 1
Co-authors Yanju Liu
2022 Bidast S, Golchin A, Baybordi A, Naidu R, 'Effects of Fe oxide-based nanoparticles on yield and nutrient content of corn in Cobalt-contaminated soils', Environmental Technology and Innovation, 26 (2022) [C1]

This study aimed to investigate the efficacy of Fe oxide nanoparticles (NPs) alleviating cobalt (Co) phytotoxicity in contaminated soils. The experiment was conducted in a greenho... [more]

This study aimed to investigate the efficacy of Fe oxide nanoparticles (NPs) alleviating cobalt (Co) phytotoxicity in contaminated soils. The experiment was conducted in a greenhouse involving Fe oxide NPs (carboxymethylcellulose (CMC)-stabilised and non-stabilised (pure) hematite, goethite, and magnetite) and concentrations of soil total Co (5, 25, 65, 125, and 185 mg kg -1). Corn plant was grown in the treated and untreated soil samples and harvested after 60 days. Results indicated that by increasing the concentration of Co in soil from 5 to 25 mg kg -1, the growth parameters and the concentrations of K, P, Fe, and Zn in the shoots of corn increased. However, in soil samples with total Co concentrations of 25 to 185 mg kg -1, the growth and concentrations of nutrients in plant aerial parts declined. At low concentrations of Co (5 and 25 mg kg -1 soil), the application of pure Fe oxide NPs and composites inhibited corn growth as well as concentrations of plant nutrients in the shoots. At high concentrations of Co in soil, the application of treatments, especially stabilised goethite, reduced the accumulation of Co in the corn plant and enhanced its growth by increasing the concentrations of nutrients in plant aerial parts. This study suggests that the efficacy of treatments in enhancing corn growth depends on the total Co concentration of soil.

DOI 10.1016/j.eti.2022.102314
Citations Scopus - 6Web of Science - 1
2022 Yuan L, Gao Y, Cheng F, Du J, Hu Z, Yang X, et al., 'The influence of oil exploitation on the degradation of vegetation: A case study in the Yellow River Delta Nature Reserve, China', ENVIRONMENTAL TECHNOLOGY & INNOVATION, 28 (2022) [C1]
DOI 10.1016/j.eti.2022.102579
Citations Scopus - 5Web of Science - 2
Co-authors Yanju Liu
2022 Hassan M, Du J, Liu Y, Naidu R, Zhang J, Ahsan MA, Qi F, 'Magnetic biochar for removal of perfluorooctane sulphonate (PFOS): Interfacial interaction and adsorption mechanism', ENVIRONMENTAL TECHNOLOGY & INNOVATION, 28 (2022) [C1]
DOI 10.1016/j.eti.2022.102593
Citations Scopus - 17Web of Science - 2
Co-authors Yanju Liu
2022 Bidast S, Golchin A, Baybordi A, Mohseni A, Naidu R, 'Impact of bare and CMC-coated Fe oxide nanoparticles on microbial activity and immobilising zinc, lead, and cadmium in a contaminated soil', ARCHIVES OF AGRONOMY AND SOIL SCIENCE, (2022) [C1]
DOI 10.1080/03650340.2022.2137875
Citations Scopus - 1
2022 Bolan S, Seshadri B, Kunhikrishnan A, Grainge I, Talley NJ, Bolan N, Naidu R, 'Differential toxicity of potentially toxic elements to human gut microbes', CHEMOSPHERE, 303 (2022) [C1]
DOI 10.1016/j.chemosphere.2022.134958
Citations Scopus - 4Web of Science - 2
Co-authors Nicholas Talley, Nanthi Bolan, Ian Grainge
2021 Halim MA, Rahman MM, Mondal D, Megharaj M, Naidu R, 'Bioaccumulation and Tolerance Indices of Cadmium in Wheat Plants Grown in Cadmium-Spiked Soil: Health Risk Assessment', Frontiers in Environmental Science, 9 (2021) [C1]

Farmers use wastewater for irrigation in many developing countries, for example Bangladesh, India, China, Sri Lanka and Vietnam because they have limited access to clean water. Th... [more]

Farmers use wastewater for irrigation in many developing countries, for example Bangladesh, India, China, Sri Lanka and Vietnam because they have limited access to clean water. This study explored cadmium (Cd) bioaccumulation in two spring wheat cultivars (cv. Mustang and Lancer), which were grown in different concentrations of Cd (0,1, 2, 4, and 8¿mg kg-1) in agricultural soils. The half maximum inhibitory concentration (IC50) values were 4.21 ± 0.29 and 4.02 ± 0.95, respectively, whereas the maximum health risk index (HRI) was 3.85 ± 0.049 and 5.33 ± 0.271, respectively, for Mustang and Lancer. In other words, the malondialdehyde content increased significantly in Mustang (around five-fold) and Lancer (around four-fold) compared with the control treatment. Results revealed that Cd content was well above the acceptable limit (HRI >1) in the two cultivars when exposed to different levels of Cd stress. The tolerant cultivar (Mustang) has potential to chelate Cd in the nonedible parts of plants in variable fractions and can be used efficiently to improve growth and macro- and micro-nutrients content while reducing Cd concentration in plants in Cd-contaminated soil. It can also diminish the HRI, which may help to protect humans from Cd risks. The two cultivars¿ nutrient availability and sorption capacity significantly shape their survival and adaptability under Cd stress. Based on what is documented in the current study, we can conclude that Mustang is more tolerant and poses fewer health hazards to people than Lancer because of its capacity to maintain grain macro- and micro-nutrients under Cd stress.

DOI 10.3389/fenvs.2021.779588
Citations Web of Science - 1
Co-authors Mahmud Rahman, Megh Mallavarapu
2021 Rashid MH, Rahman MM, Halim MA, Naidu R, 'Growth, metal partitioning and antioxidant enzyme activities of mung beans as influenced by zinc oxide nanoparticles under cadmium stress', CROP & PASTURE SCIENCE, 73 862-876 (2021) [C1]
DOI 10.1071/CP21598
Citations Scopus - 6Web of Science - 6
Co-authors Mahmud Rahman
2021 Wang L, Cheng Y, Naidu R, Chadalavada S, Bekele D, Gell P, et al., 'Application of portable gas chromatography mass spectrometer for rapid field based determination of TCE in soil vapour and groundwater', Environmental Technology and Innovation, 21 (2021) [C1]

The application of portable chromatography¿mass spectrometer (GC¿MS) is restrained by its detection limits without the development of proper sample pre-concentration methods. The ... [more]

The application of portable chromatography¿mass spectrometer (GC¿MS) is restrained by its detection limits without the development of proper sample pre-concentration methods. The primary focus of this paper is to introduce a practical field measurement methodology for the analysis of volatile organic compounds (VOCs) in soil vapour and groundwater using a portable gas (GC¿MS)system for application to in situ assessment of vapour intrusion from VOC contamination. A solid-phase micro-extraction (SPME) technique was applied for sample pre-concentration before the GC¿MS¿ measurement. Practical in-field soil gas SPME sampling methods have been developed to optimise the SPME extraction efficiency to then ultimately improve the detection limits of portable GC¿MS. An Australian site impacted by a chlorinated VOC, trichloroethylene (TCE), was the subject of the case study. To rapidly assess soil vapour samples in subsurface soil, in-house-developed retractable soil vapour sampling probes (SVSPs) were installed at the site in clusters at depths of 1 m, 2 m and 3 m below ground level at each sampling location. Use of the SVSPs for sampling enabled the generation of a three-dimensional map and distribution contours for TCE concentrations using the in situ measurement results of a portable GC¿MS analysis for vapour intrusion investigation. The results of the portable GC¿MS¿ analysis were compared with the results from conventional USEPA methods, such as TO-15 and Method 8265 for soil vapour and groundwater samples, respectively. This work demonstrates that the developed methodology of using a portable GC¿MS system has the capability for in-field quantitative analysis of VOCs for rapid contaminated site vapour intrusion assessment.

DOI 10.1016/j.eti.2020.101274
Citations Scopus - 9Web of Science - 5
Co-authors Ying Cheng, Liang Wang, Dawit Bekele, Sreenivasulu Chadalavada
2021 Sobhani Z, Panneerselvan L, Fang C, Naidu R, Megharaj M, 'Chronic and Transgenerational Effects of Polystyrene Microplastics at Environmentally Relevant Concentrations in Earthworms (
DOI 10.1002/etc.5072
Citations Scopus - 43Web of Science - 31
Co-authors Logeshwaran Panneerselvan, Cheng Fang, Zahra Sobhani, Megh Mallavarapu
2021 Sobhani Z, Panneerselvan L, Fang C, Naidu R, Megharaj M, 'Chronic and transgenerational effects of polyethylene microplastics at environmentally relevant concentrations in earthworms', ENVIRONMENTAL TECHNOLOGY & INNOVATION, 25 (2021) [C1]
DOI 10.1016/j.eti.2021.102226
Citations Scopus - 20Web of Science - 5
Co-authors Zahra Sobhani, Cheng Fang, Megh Mallavarapu, Logeshwaran Panneerselvan
2021 Asadi P, Heidari A, Alaie E, Naidu R, Asadi H, Mahmoodi S, 'Use of modified and petroleum -impregnated bentonite mulch as an eco-friendly stabilizer of wind erodible sands', Aeolian Research, 53 (2021) [C1]

This study aimed to develop a method for the management of petroleum pollutants released into the environment using modified bentonite and to evaluate the use of petroleum-impregn... [more]

This study aimed to develop a method for the management of petroleum pollutants released into the environment using modified bentonite and to evaluate the use of petroleum-impregnated modified bentonite, as an eco-friendly and resistant mulch to stabilize mobile sands exposed to wind erosion. Bentonite was modified using hexa-decyl-tri-methyl-ammonium bromide to increase its capacity for petroleum adsorption. The resistivity to breakdown of the produced mulch was determined against wind, runoff, and by drainage water caused by simulated rainfall. Results showed that the basal spacing of the modified bentonite increased 162% compared to unmodified bentonite and it was able to adsorb petroleum, 5 times its base weight. The produced mulch was resistant against wind flows up to 16.7 m s-1 with no soil loss during 5 min, while the untreated sandy soil started to move at a threshold speed of 10.3 m s-1 (with a soil loss rate of 53 g m-2 s-1) and the tray of soil was fully eroded after 135 s. Analysis of the drainage waters which passed through the mulch showed that mulch 2 (ratio 5:1, sandy soil: modified clay + unmodified clay (1:1) mixed by petroleum) retained more polycyclic aromatic hydrocarbons compounds, compared to mulches 1 (ratio of 5:1 sandy soil: unmodified bentonite mixed with petroleum) and 3 (ratio 5:1:0.5, sandy soil: unmodified clay: modified clay mixed by petroleum). Analysis of the runoff water samples also showed that PAHs retention in mulch 2 is significantly higher than the amounts retained by mulches 1 and 3.

DOI 10.1016/j.aeolia.2021.100749
2021 Siddique AB, Rahman MM, Islam MR, Shehzad MT, Nath B, Naidu R, 'Influence of iron plaque on accumulation and translocation of cadmium by rice seedlings', Sustainability (Switzerland), 13 (2021) [C1]

This study investigated the impact of soil type and rice cultivars on variations in the iron plaque formation and cadmium (Cd) accumulation by different portions of rice seedlings... [more]

This study investigated the impact of soil type and rice cultivars on variations in the iron plaque formation and cadmium (Cd) accumulation by different portions of rice seedlings under the influence of Fe amendment. The experiments were performed in pots under glasshouse conditions using two typical paddy soils. Rice seedlings were exposed to three concentrations of Cd (0, 1 and 3 mg kg-1 soil) and Fe (0, 1.0 and 2.0 g kg-1 soil). The results revealed that shoot biomass decreased by 12.2¿23.2% in Quest and 12.8¿30.8% in Langi in the Cd1.0 and Cd3.0 treatments, while shoot biomass increased by 11.2¿19.5% in Quest and 26¿43.3% in Langi in Fe1.0 and Fe2.0 as compared to the Fe control. The Cd concentration in the roots and shoots of rice seedlings were in the order of Langi cultivar > Quest cultivar, but the Fe concentration in rice tissues showed the reverse order. Fe plaque formations were promoted by Fe application, which was 7.8 and 10.4 times higher at 1 and 2 g kg-1 Fe applications compared to the control Fe treatment. The Quest cultivar exhibited 13% higher iron plaque formation capacity compared to the Langi cultivar in both soil types. These results indicate that enhanced iron plaque formation on the root surface was crucial to reduce the Cd concentration in rice plants, which could be an effective strategy to regulate grain Cd accumulation in rice plants.

DOI 10.3390/su131810307
Citations Scopus - 6Web of Science - 3
Co-authors Mahmud Rahman
2021 Deb AK, Biswas B, Goswami N, Hilder EF, Naidu R, Rahman MM, 'Synthesis of environmentally benign ultra-small copper nanoclusters-halloysite composites and their catalytic performance on contrasting azo dyes', Applied Surface Science, 546 (2021) [C1]

Supported metal nanoclusters (NCs) are an ideal catalytic system from their ultra-small size (&lt;3 nm), reactivity and confinement on support materials. Whether synthesis of such... [more]

Supported metal nanoclusters (NCs) are an ideal catalytic system from their ultra-small size (<3 nm), reactivity and confinement on support materials. Whether synthesis of such composite is feasible using copper (Cu) as catalyst on nontoxic and inexpensive support material but without using any toxic reducing agent is yet to be explored. Here, synthesis of CuNCs using only biocompatible glutathione and localised them on halloysite nanotubes (HNTs) would be a sustainable catalyst composite. Following hydrothermal reaction, composites CuNCs@HNT and CuNCs@HNT-PS were synthesised by one-step and post-synthesis methods, respectively. State-of-the-art tools, including high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy revealed NCs formation, chemical states, and confinement and stability as composite, while catalysis reaction was monitored by spectrophotometer. Both composites exhibited faster catalytic performance than did bare NCs for the degradation of contrasting model azo dyes, methylene blue (MB) and methyl orange (MO). CuNCs, CuNCs@HNT and CuNCs@HNT-PS required only 93 ± 1.0, 17.5 ± 2.5 and 27 ± 2.5 s, respectively for 100% degradation of MB whereas >90% degradation of MO occurred by 120 ± 5.21, 75 ± 3.15 and 90 ± 3.61 min, respectively. Composites showed excellent catalytic reusability and environmental nontoxicity. Therefore, as effective and safe catalysts, they can shed light on exploring further usage in the environment and industrial set-ups.

DOI 10.1016/j.apsusc.2021.149122
Citations Scopus - 29Web of Science - 21
Co-authors Bhaba Biswas, Mahmud Rahman
2021 Logeshwaran P, Sivaram AK, Surapaneni A, Kannan K, Naidu R, Megharaj M, 'Exposure to perfluorooctanesulfonate (PFOS) but not perflurorooctanoic acid (PFOA) at ppb concentration induces chronic toxicity in Daphnia carinata', Science of the Total Environment, 769 (2021) [C1]

Widespread environmental contamination of per- and polyfluoroalkyl substances (PFAS) is well established. Nevertheless, few studies have reported on the aquatic toxicity of PFAS, ... [more]

Widespread environmental contamination of per- and polyfluoroalkyl substances (PFAS) is well established. Nevertheless, few studies have reported on the aquatic toxicity of PFAS, especially in indicator species such as Daphnia. In this study, the toxicity of two major PFAS, namely perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS), was investigated on water flea (Daphnia carinata) using a battery of comprehensive toxicity tests, including a 48 h acute and a 21-day chronic assays. The survival, growth, and reproduction of D. carinata were monitored over a 21-day life cycle. PFOS exhibited higher toxicity than PFOA. The 48 h LC50 values (confidence interval) based on acute toxicity for PFOA and PFOS were 78.2 (54.9¿105) mg L-1 and 8.8 (6.4¿11.6) mg L-1, respectively. Chronic exposure to PFOS for 21 days displayed mortality and reproductive defects in D. carinata at a concentration as low as 0.001 mg L-1. Genotoxicity assessment using comet assay revealed that exposure for 96 h to PFOS at 1 and 10.0 mg L-1 significantly damaged the organism's genetic makeup. The results of this study have great implications for risk assessment of PFOS and PFOA in aquatic ecosystems, given the potential of PFOS to pose a risk to Daphnia even at lower concentrations (1 µg L-1).

DOI 10.1016/j.scitotenv.2020.144577
Citations Scopus - 26Web of Science - 18
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2021 Li BT, Zhou ZQ, Naidu R, Hu ZQ, Guo DB, Chen JX, 'Combined Remediation of Eutrophic Water by Phoslock and Aerobic Denitrifying Bacteria', Huanjing Kexue/Environmental Science, 42 1861-1869 (2021) [C1]

Nitrogen and phosphorus are the leading causes of water eutrophication, and it is challenging to remove nitrogen and phosphorus effectively through a single water remediation meth... [more]

Nitrogen and phosphorus are the leading causes of water eutrophication, and it is challenging to remove nitrogen and phosphorus effectively through a single water remediation method. In this study, an aerobic denitrifying bacterium (AD-19) isolated from eutrophic water was used to construct an immobilized biofilm and combined with Phoslock¿ to remove nitrogen and phosphorus from the water. The phosphorus control efficiency of Phoslock¿, nitrogen removal performance of the denitrifying bacteria, and combined remediation performance for the eutrophic water were studied. The results demonstrated that the removal rate of PO43--P in the simulated eutrophic water reached 95% with a dosing ratio of 80 (mass ratio of Phoslock¿ to PO43--P), and phosphorus release from sediment was effectively inhibited at the same time. Strain AD-19, which was identified as Pseudomonas sp. Using the 16S rDNA method, had a good heterotrophic nitrification and aerobic denitrification ability, and more than 97% of the nitrogen was removed when NH4+-N or NO3--N was used as the nitrogen source. The feasibility of the combined remediation of the eutrophic water was demonstrated using a lake simulation device. Furthermore, this technique was used to restore a eutrophic pond in a park in Wuhan city. After 16 days of treatment, the water quality indices for nitrogen and phosphorus were improved from worse than Grade ¿ to Grade ¿ (GB 3838-2002, Ministry of Environmental Protection of China, 2002) and remained stable for more than 270 days, indicating that Phoslock¿ combined with the immobilized biofilm could quickly and effectively restore eutrophic water as well as maintain the water quality for long periods.

DOI 10.13227/j.hjkx.202008232
Citations Scopus - 4
2021 Zazouli MA, Dehbandi R, Mohammadyan M, Aarabi M, Dominguez AO, Kelly FJ, et al., 'Physico-chemical properties and reactive oxygen species generation by respirable coal dust: Implication for human health risk assessment', JOURNAL OF HAZARDOUS MATERIALS, 405 (2021) [C1]
DOI 10.1016/j.jhazmat.2020.124185
Citations Scopus - 38Web of Science - 23
Co-authors Mahmud Rahman
2021 Kulathunga MRDL, Wijayawardena MAA, Naidu R, 'Heavy metal(loid)s and health risk assessment of Dambulla vegetable market in Sri Lanka.', Environ Monit Assess, 193 230 (2021) [C1]
DOI 10.1007/s10661-021-09020-2
Citations Scopus - 5Web of Science - 3
Co-authors Ayanka Wijayawardena
2021 Sobhani Z, Fang C, Naidu R, Megharaj M, 'Microplastics as a vector of toxic chemicals in soil: Enhanced uptake of perfluorooctane sulfonate and perfluorooctanoic acid by earthworms through sorption and reproductive toxicity', Environmental Technology and Innovation, 22 (2021) [C1]

The accumulation of microplastics (MP) in soil via their continuous release and degradation of large plastics has recently become a serious global problem. The major concern with ... [more]

The accumulation of microplastics (MP) in soil via their continuous release and degradation of large plastics has recently become a serious global problem. The major concern with MP is their potential to sorb pollutants as well as ingestion by living organisms. Hence, this study focused on the effect of PVC MP exposure on increasing the risk of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) bioaccumulation in earthworms in addition to their reproduction. In general, the bioaccumulation factor (BAF) for PFOA and PFOS increased up to 200% in earthworms exposed to MP-contaminated soil. MP at 500 and 1000 mg kg -1 soil caused enhanced uptake of PFOS and PFOA in earthworms, and a significant reduction in their reproduction. These results have significant implications for risk assessment of MP in soil.

DOI 10.1016/j.eti.2021.101476
Citations Scopus - 44Web of Science - 23
Co-authors Megh Mallavarapu, Zahra Sobhani, Cheng Fang
2021 Kumar S, Zhao M, Zhang H, Rahman MA, Luo C, Rahman MM, 'Distribution, contamination status and source of trace elements in the soil around brick kilns', Chemosphere, 263 127882-127882 (2021) [C1]
DOI 10.1016/j.chemosphere.2020.127882
Citations Scopus - 23Web of Science - 12
Co-authors Mahmud Rahman
2021 Hassan M, Deb AK, Qi F, Liu Y, Du J, Fahy A, et al., 'Magnetically separable mesoporous alginate polymer beads assist adequate removal of aqueous methylene blue over broad solution pH', Journal of Cleaner Production, 319 (2021) [C1]

Adsorption is a promising technology for removal of organic and inorganic contaminants from soil and water system. In this study, magnetically separable mesoporous polymeric beads... [more]

Adsorption is a promising technology for removal of organic and inorganic contaminants from soil and water system. In this study, magnetically separable mesoporous polymeric beads (NiZnFe4O4-HNT@alg) were synthesised for efficient removal of methylene blue (MB, cationic dye) under broad solution pH (from pH 3.41 to pH 8.43). Alginate biopolymer were used to stabilize halloysite nanotubes (HNTs) and nickel zinc iron oxide nanoparticles (NiZnFe4O4 < 100 nm). NiZnFe4O4 was incorporated onto the polymer beads to generate the adsorbents' magnetic properties and catalytic degradability. The adsorbent (NiZnFe4O4-HNT@alg) have higher surface area (122.43 m2/g), suitable mesoporosity (~6.68 nm), larger pore volume (0.11 cm3/g), and abundance of active sites, enabling high adsorption capacity (264 mg/g) of MB. The abundance of hydroxyl, carboxyl, and siloxane groups enabled cationic dye sorption through ionic interaction. The removal efficiency of MB was ~99% under a wide solution pH range from 10 mg/L of MB, in which the adsorbent dose was 2 g/L. Both Langmuir (R2 = 0.99; p < 0.001) and Freundlich (R2 = 0.99; p < 0.001) isotherm models fitted well, whereas trends of kinetics model fitting are pseudo-second-order (R2 = 0.99) > intraparticle diffusion (R2 = 0.93) > pseudo-first-order (R2 = 0.87). Energy-dispersive X-ray spectroscopy (EDS) elemental mapping demonstrated that MB has a co-distribution with silicon, aluminium, and alginate carbon phase but is limited with iron and nickel, indicating HNTs and alginate polymer performed as sorption sites, whereas NiZnFe4O4 performed as a catalyst. The presence (post-sorption) and absence (pre-sorption) of inorganic, total carbon or total organic carbon content at different solution pH, contact time, and initial concentration of MB demonstrated that the adsorbent act as a catalyst as well for degradation of MB. NiZnFe4O4-HNT@alg triggers efficient removal of MB with the assist of adsorption and catalytic degradation at broad solution pH. A comparison in removal of MB by various adsorbents including, biochars, clays, activated carbon, nanoparticles, polymers, nano composites, graphene oxides, carbon nanotubes, and polymer beads with the result of this study were performed, illustrating competitive sorption capacity of NiZnFe4O4-HNT@alg.

DOI 10.1016/j.jclepro.2021.128694
Citations Scopus - 21Web of Science - 6
Co-authors Yanju Liu, Adam Fahy
2021 Sheikh Fakhradini S, Moore F, Keshavarzi B, Naidu R, Wijayawardena A, Soltani N, Rostami S, 'Spatial distribution, partitioning, ecological risk and source apportionment of potential toxic elements in water and sediments of the Hoor Al-Azim wetland and their bioaccumulation in selected commercial fish species', Marine Pollution Bulletin, 172 (2021) [C1]

The potentially toxic elements (PTEs) concentrations in water and sediments were measured in the Hoor Al-Azim wetland to evaluate the spatial distribution, pollution rate, fate, p... [more]

The potentially toxic elements (PTEs) concentrations in water and sediments were measured in the Hoor Al-Azim wetland to evaluate the spatial distribution, pollution rate, fate, partitioning, and ecological risk and also to recognize the PTEs sources in sediments using MLR-APCs (multiple linear regression-absolute principal component scores) receptor model. The human health risk was investigated based on the seven fish species consumed in the study area. Based on the results, water and sediment contamination was observed at some stations in the southern part of the wetland where agricultural water drains. Also, the sediments of oil well drilling disposal site was polluted by PTEs. Based on the MLR-APCs model, 80.8% of Mo and 81.5% of Se originated from agricultural source. Total target hazard quotients (TTHQ) values suggested that the children could experience adverse health effects due to consumption of Coptodon zillii, Aspius vorax, Carassius auratus and Carasobarbus luteus.

DOI 10.1016/j.marpolbul.2021.112875
Citations Scopus - 5Web of Science - 1
Co-authors Ayanka Wijayawardena
2021 Zhang J, Hu H, Wang M, Li Y, Wu S, Cao Y, et al., 'Land application of sewage sludge biochar: Assessments of soil-plant-human health risks from potentially toxic metals', Science of the Total Environment, 756 (2021) [C1]

Effects of sewage sludge-derived biochar and its precursor on the accumulation of metals (Cd, Cu, Pb and Zn) in soil and their uptake by plants in a 1-year field experiment involv... [more]

Effects of sewage sludge-derived biochar and its precursor on the accumulation of metals (Cd, Cu, Pb and Zn) in soil and their uptake by plants in a 1-year field experiment involving corn-radish rotation were comparatively studied. The human health risks were assessed, and the safe application period of biochar were estimated. The application of biochar, compares to sewage sludge, significantly enhanced the radish yield (p < 0.05; not corn yield) and significantly reduced the accumulation of metals in both plants (p < 0.05), especially the annual application at =15 t ha-1. The hazard quotient analyses of the metals showed there were no health risks to humans (Hazard Index < 1) in consuming the edible parts of the both plants. The application of sewage sludge at =15 t ha-1 resulted in Cd in radish exceeded the threshold for foodstuffs set by China (0.1 mg kg-1). The total contents of Cd, Cu, Pb and Zn in soil increased gradually as the application of sewage sludge or its biochar increased from 7.5 t ha-1 to 30 t ha-1. More metals were found to be introduced to soil by the land application of biochar than by its precursor at the same doses, because the metals were concentrated in biochar during the preparation process. The contamination risk assessment of soil based on the geo-accumulation index, the contamination factor and the pollution load index suggested the application of biochar on farmland should <15 t ha-1. Therefore, taking into account the yield of and metal concentrations in the radish and corn plants and the contamination risks in soil, it is recommended that the continuous safe application period at an application of 7.5 t ha-1 year-1 of biochar should not exceed 15 years, and that of its precursor sewage sludge should not exceed 17 years.

DOI 10.1016/j.scitotenv.2020.144137
Citations Scopus - 41Web of Science - 33
Co-authors Yanju Liu
2021 Islam MR, Sanderson P, Payne TE, Johansen MP, Naidu R, 'Desorption and Migration Behavior of Beryllium from Contaminated Soils: Insights for Risk-Based Management', ACS Omega, 6 30686-30697 (2021) [C1]

Factors influencing the desorption, distribution, and vertical migration behavior of Be in contaminated soils are not fully understood. This study examined the desorption and migr... [more]

Factors influencing the desorption, distribution, and vertical migration behavior of Be in contaminated soils are not fully understood. This study examined the desorption and migration of Be in a soil profile from a legacy radioactive waste disposal site using different batch leaching [monofilled waste extraction procedure (MWEP); synthetic precipitation leaching procedure (SPLP); simulated acid rain solution (SARS); and toxicity characteristic leaching procedure] and sequential leaching [community bureau of reference (BCR)] methods for insights relevant to the application of risk-based management. The results showed that Be desorption was higher in the presence of organic than the inorganic leachate composition (MWEP < SPLP < SARS < TCLP < BCR first-step). The desorption followed three diffusion control mechanisms, which resulted in three desorption rate constant estimates of 157, 87.1, and 40.4 Be/kg.h0.5, and the estimated desorption maximum was 556 µg/kg. The desorption process was, spontaneous (dG > 0), enthalpically and entropically influenced. Increasing the incubation period and heat treatment resulted in a decrease of Be desorption and migration. The soil clay content and pH were the primary factors influencing Be desorption, and the results suggested that Be was desorbed from metal oxyhydroxides and surfaces of silicates (e.g., reactive surfaces of clay minerals), organic matters, and soil pores. Because of high Kd values, the mobility of Be was limited, and no exceedances of ecological or human health risk index or guidelines were determined for the current contamination levels at the site. However, Be released from the waste trenches has the ongoing potential to increase Be concentration in the soil.

DOI 10.1021/acsomega.1c04572
Citations Scopus - 5Web of Science - 3
Co-authors Mdrashidul Islam
2021 Siddique AB, Rahman MM, Islam MR, Mondal D, Naidu R, 'Response of Iron and Cadmium on Yield and Yield Components of Rice and Translocation in Grain: Health Risk Estimation', Frontiers in Environmental Science, 9 (2021) [C1]

Rice consumption is a major dietary source of Cd and poses a potential threat to human health. The aims of this study were to examine the influence of Fe and Cd application on yie... [more]

Rice consumption is a major dietary source of Cd and poses a potential threat to human health. The aims of this study were to examine the influence of Fe and Cd application on yield and yield components, dynamics of Cd in pore water, translocation factors, daily dietary intake, and estimation of human health risks. A pot experiment was performed under glasshouse conditions where rice cultivars (Langi and Quest) were cultivated in two dissimilar soils under different levels of Cd (0, 1.0, and 3.0¿mg¿kg-1) and Fe (0, 1.0, and 2.0¿g¿kg-1). The results showed that variation in two rice cultivars in terms of yield and yield-related components was dose dependent. Cadmium concentration in soil pore water was decreased over time and increased with increasing Cd levels but decreased with Fe application. Translocation factors (TFs) from root to straw (TFroot-straw) or straw to husk (TFstraw-husk) were higher than root to grain (TFroot-grain) or straw to grain (TFstraw-grain). The Quest cultivar had 20% lower Cd than the Langi cultivar. Application of Fe at the rate of 1 and 2¿g¿kg-1 soil reduced Cd by 23 and 46%, respectively. Average daily intake (ADI) of Cd exceeded the permissible limit (5.8 × 10-3¿mg -1¿kg-1¿bw per week) when rice plant subjected 1 and 3¿mg¿kg-1 Cd stress with or without Fe application. Results also indicated that ADI value was lower in the Quest cultivar as compared to the Langi cultivar. Estimation of human health risk revealed that the non-carcinogenic risks (HQ > 1) and carcinogenic risks (CR > 1.0 × 10-4) increased with increasing Cd levels in the soil. The application of Fe decreased the human health risks from rice consumption which is more pronounced in Fe 2.0 than in Fe1.0 treatments. The rice cultivar grown in soil-1 (pH 4.6) showed the highest health risks as compared to soil-2 (pH 6.6) and the Quest cultivar had lower health risks than the Langi cultivar.

DOI 10.3389/fenvs.2021.716770
Citations Scopus - 8Web of Science - 7
Co-authors Mahmud Rahman
2021 Wang L, Cheng Y, Naidu R, Gell P, Bowman M, 'Rapid In-Field Approaches for Delineating VOC in Both Soil Vapour and Groundwater for Vapour Intrusion Assessment', Frontiers in Environmental Science, 9 (2021) [C1]

Traditional contaminated site characterisation approaches are time-consuming, labour-intensive, and demand a high level of expertise. This case study provides a rapid field-based ... [more]

Traditional contaminated site characterisation approaches are time-consuming, labour-intensive, and demand a high level of expertise. This case study provides a rapid field-based solution to investigating a VOC contaminated site and its vapour incursion by combining soil vapour and groundwater survey. To fully assess the volatile organic compound (VOC) distribution in a contaminated site, a number of self-developed soil vapour sampling probes (SVSPs) were placed vertically at different locations in a grid with different depths. Hence, 3D subsurface contour maps for VOC concentrations in soil vapour can be obtained and used to help identify hot spots and the migration patterns of VOCs. This SVSP is ¿easy-to-install¿ in the field and a cost-effective solution for rapid assessment of soil vapour samples. The SVSPs can be installed both vertically and horizontally. If there is a requirement to take soil vapour samples beneath an existing building from a potential contamination source zone, SVSPs can be horizontally installed beneath the building without compromising its structural integrity. In addition, to ascertain the correct groundwater channels that are likely to carry contaminants from a potential source zone, an electrical resistivity tomography technique was employed to provide the preliminary information for groundwater delineation in a complex groundwater channel network.

DOI 10.3389/fenvs.2021.746195
Citations Scopus - 3Web of Science - 1
Co-authors Liang Wang, Ying Cheng
2021 Wang L, Cheng Y, Naidu R, Bowman M, 'The Key Factors for the Fate and Transport of Petroleum Hydrocarbons in Soil With Related in/ex Situ Measurement Methods: An Overview', Frontiers in Environmental Science, 9 (2021) [C1]

Once petroleum hydrocarbons (PHs) are released into the soil, the interaction between PHs and soil media is dependent not only upon the soil properties but also on the characteris... [more]

Once petroleum hydrocarbons (PHs) are released into the soil, the interaction between PHs and soil media is dependent not only upon the soil properties but also on the characteristics of PHs. In this study, the key factors influencing the interactions between PHs and soil media are discussed. The key factors include: 1) the characteristics of PHs, such as volatility and viscosity; and 2) soil properties, such as porosity, hydraulic properties and water status, and organic matter; and 3) atmospheric circumstances, such as humidity and temperature. These key factors can be measured either ex-situ using conventional laboratory methods, or in situ using portable or handheld instruments. This study overviews the current ex/in situ techniques for measuring the listed key factors for PH contaminated site assessments. It is a tendency to apply in situ methods for PH contaminated site characterisation. Furthermore, handheld/portable Fourier transform infrared spectroscopy (FTIR) instrument provides tremendous opportunities for in-field PH contaminated site assessment. This study also reviewed the non-destructive FTIR spectroscopy analysis coupling with handheld FTIR for in-field PH contaminated site characterisation, including determining the concentration of total PH, dominant PH fractions and soil key properties for PH transport modelling.

DOI 10.3389/fenvs.2021.756404
Citations Scopus - 9Web of Science - 2
Co-authors Ying Cheng, Liang Wang
2021 Fang C, Sobhani Z, Zhang X, McCourt L, Routley B, Gibson CT, Naidu R, 'Identification and visualisation of microplastics / nanoplastics by Raman imaging (iii): algorithm to cross-check multi-images', Water Research, 194 (2021) [C1]

We recently developed the Raman mapping image to visualise and identify microplastics / nanoplastics (Fang et al. 2020, Sobhani et al. 2020). However, when the Raman signal is low... [more]

We recently developed the Raman mapping image to visualise and identify microplastics / nanoplastics (Fang et al. 2020, Sobhani et al. 2020). However, when the Raman signal is low and weak, the mapping uncertainty from the individual Raman peak intensity increases and may lead to images with false positive or negative features. For real samples, even the Raman signal is high, a low signal-noise ratio still occurs and leads to the mapping uncertainty due to the high spectrum background when: the target plastic is dispersed within another material with interfering Raman peaks; materials are present that exhibit broad Raman peaks; or, materials are present that fluoresce when exposed to the excitation laser. In this study, in order to increase the mapping certainty, we advance the algorithm to combine and merge multi-images that have been simultaneously mapped at the different characteristic peaks from the Raman spectra, akin imaging via different mapping channels simultaneously. These multi-images are merged into one image via algorithms, including colour off-setting to collect signal with a higher ratio of signal-noise, logic-OR to pick up more signal, logic-AND to eliminate noise, and logic-SUBTRACT to remove image background. Specifically, two or more Raman images can act as ¿parent images¿, to merge and generate a ¿daughter image¿ via a selected algorithm, to a ¿granddaughter image¿ via a further selected algorithm, and to an ¿offspring image¿ etc. More interestingly, to validate this algorithm approach, we analyse microplastics / nanoplastics that might be generated by a laser printer in our office or home. Depending on the toner and the printer, we might print and generate millions of microplastics and nanoplastics when we print a single A4 document.

DOI 10.1016/j.watres.2021.116913
Citations Scopus - 54Web of Science - 42
Co-authors Zahra Sobhani, Cheng Fang
2021 Bagherifam S, Brown TC, Fellows CM, Naidu R, Komarneni S, 'Highly efficient removal of antimonite (Sb (III)) from aqueous solutions by organoclay and organozeolite: Kinetics and Isotherms', Applied Clay Science, 203 (2021) [C1]

Clays modified by cationic surfactants have been widely used for the removal of organic and inorganic anionic contaminants. However, their suitability for the removal of antimonit... [more]

Clays modified by cationic surfactants have been widely used for the removal of organic and inorganic anionic contaminants. However, their suitability for the removal of antimonite from aqueous solutions has not been systematically studied. In this study, hexadecylpyridinium chloride modified montmorillonite (HDPy+-M) and hexadecylpyridinium bromide modified zeolite (HDPy+-Z) were used to measure Sb(III) uptake from solutions containing 0.5¿2.5 mM antimonite. Adsorption isotherms of antimonite were studied using the Langmuir and Freundlich equations. Adsorption kinetics were investigated using pseudo-first-order, pseudo-second-order, Elovich and intra-particle diffusion models. The results of X-ray diffraction showed a large interlayer expansion for HDPy+-M, whereas the X-ray patterns of HDPy+-Z remained unchanged. Uptake of Sb(III) by both HDPy+-M and HDPy+-Z could be fitted well to the Langmuir isotherm, while the kinetics of adsorption could be described well using the pseudo-second-order model. Maximum adsorption capacities for Sb(III) uptake by HDPy+-M and HDPy+-Z were calculated to be 108.7 and 61.34 mg g-1, respectively. The results of the kinetic studies revealed that Sb(III) adsorption to HDPy+-Z was found to be quite fast and the reaction reached equilibrium in 8 h, whereas for HDPy+-M equilibration was attained within 24 h. The adsorption of antimonite onto both HDPy+-M and HDPy+-Z was found to be selective in the presence of Cl-1 and SO4-2 competitive anions. Considering the high affinity for Sb(III) uptake from solutions containing high concentrations of antimonite, both HDPy+-M and HDPy+-Z could be used as promising adsorbents for environmental applications.

DOI 10.1016/j.clay.2021.106004
Citations Scopus - 12Web of Science - 6
2021 Sivaram AK, Logeshwaran P, Surapaneni A, Shah K, Crosbie N, Rogers Z, et al., 'Evaluation of Cyto-genotoxicity of Perfluorooctane Sulfonate (PFOS) to Allium cepa', ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 40 792-798 (2021) [C1]
DOI 10.1002/etc.4905
Citations Scopus - 13Web of Science - 12
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2021 Gerdelidani AF, Towfighi H, Shahbazi K, Lamb DT, Choppala G, Abbasi S, et al., 'Arsenic geochemistry and mineralogy as a function of particle-size in naturally arsenic-enriched soils', Journal of Hazardous Materials, 403 (2021) [C1]
DOI 10.1016/j.jhazmat.2020.123931
Citations Scopus - 41Web of Science - 24
Co-authors Girish Choppala, Mahmud Rahman
2021 Rathnayake IVN, Megharaj M, Beer M, Naidu R, 'Medium composition affects the heavy metal tolerance of microalgae: a comparison', Journal of Applied Phycology, 33 3683-3695 (2021) [C1]

Tolerance of the three metals cadmium (Cd), copper (Cu), and zinc (Zn) by four microalgal species was investigated in three different culture media available in the literature tog... [more]

Tolerance of the three metals cadmium (Cd), copper (Cu), and zinc (Zn) by four microalgal species was investigated in three different culture media available in the literature together with a modified version in order to study the effect of growth media components in estimating the bioavailability of metals introduced into the medium. The free metal content of each medium was also determined using Visual MINTEQ version 3.1 to compare the bioassays. Four microalgal isolates were identified as Desmodesmus sp-I, Desmodesmus sp-II, Coelastrella sp., and Chlorella vulgaris. The present work demonstrated that the microalgal media components have a profound effect on the bioavailability of the metals in the media, so that the bioassay results may vary depending on the growth medium used in the experiments. Furthermore, the free metal contents in each media varied depending on the concentrations of metals added. The tolerance of microalgae evaluated as 50% effective concentration (EC50) of metals differed significantly (p < 0.05) depending on the growth medium used and also varied between the species of the same genus. Desmodesmus sp-I showed high sensitivity to Cd (EC50 0.220 ± 0.011¿mg L-1) and Zn (EC50 0.464 ± 0.065¿mg L-1), whereas Desmodesmus sp-II showed high sensitivity to Cu (EC50 0.098 ± 0.002¿mg L-1) when grown in Test Medium 1 (TM1). The Chlorella vulgaris strain was found to be the most resistant microalga among the four isolates tested in this study. This study has significant implications for the risk assessment of these metals using algal bioassays.

DOI 10.1007/s10811-021-02589-8
Citations Scopus - 5Web of Science - 3
Co-authors Megh Mallavarapu
2021 Abbasi S, Lamb D, Rahman MA, Naidu R, Megharaj M, 'Response of phosphorus sensitive plants to arsenate', Environmental Technology and Innovation, 24 (2021) [C1]

Arsenate (As (V)) is a highly toxic species of arsenic (As) which is also an excellent phosphate analogue. Plant species that are adapted to phosphorus (P) impoverished soil displ... [more]

Arsenate (As (V)) is a highly toxic species of arsenic (As) which is also an excellent phosphate analogue. Plant species that are adapted to phosphorus (P) impoverished soil display a negative response to elevated phosphate due to an inability to downregulate P acquisition. Despite widespread As contamination and shared transport systems for As (V) and P uptake, little to no information is available on the response of P-sensitive plants to As (V). The aim of the study was to investigate the response of P-sensitive plants to As (V). One high (Hakea prostrata R.BR) and one moderate (Banksia seminuda B.Rye) P-sensitive species and one vegetable plant species (Cucumis sativus L.) were grown in nutrient solution containing different As (V) concentrations. Based on EC50 data from nutrient culture, Hakea prostrata was the most sensitive species to As (V) followed by B. seminuda and C. sativus. Critical exogenous concentrations of As that reduced plant growth by 50 % (EC50) in H. prostrata, B. seminuda and C. sativus were respectively 0.64, 0.76 and 1.08 µM for shoot and 0.66, 0.51, 1.07 µM for root. Hakea prostrata had the highest translocation factor (ratio of As concentration in shoot to root) of 0.11, followed by B. seminuda (0.03), and C. sativus (0.01). Plant species with high and moderate P sensitivity were associated with high sensitivity to As (V) exposure and accumulation in shoots. The increased sensitivity has important implications in ecological risk assessment and selection of plant species for rehabilitation. The impacts of As(V) at low P levels in soil solution is needed to inform contaminated site assessment and rehabilitation.

DOI 10.1016/j.eti.2021.102008
Citations Scopus - 4Web of Science - 1
Co-authors Megh Mallavarapu
2021 Najafi Z, Golchin A, Naidu R, 'The effects of chitosan composites on the immobilization of chromium in soil and marigold (Calendula officinalis) growth', INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY, 19 6057-6070 (2021) [C1]
DOI 10.1007/s13762-021-03780-7
2021 Khan AUH, Liu Y, Naidu R, Fang C, Dharmarajan R, Shon H, 'Interactions between zinc oxide nanoparticles and hexabromocyclododecane in simulated waters', Environmental Technology and Innovation, 24 (2021) [C1]

The zinc oxide nanoparticles (ZnO-NPs) have been increasingly applied in industries and consumer products, causing release of these nanoparticles in environments. The behaviour of... [more]

The zinc oxide nanoparticles (ZnO-NPs) have been increasingly applied in industries and consumer products, causing release of these nanoparticles in environments. The behaviour of ZnO-NPs in the water systems is complicated due to the presence of different cations, anions, organic substances (e.g. humic acid HA) and other organic pollutants (e.g. commonly used brominated flame retardant, BFR). In particular, the aggregation and alteration of these nanoparticles can be influenced by co-existence contaminants. In this study, the interactions between hexabromocyclododecane (HBCD) and ZnO-NPs were investigated for the physicochemical properties and colloidal stability changes in various simulated waters. This is significant to understand the fate and behaviour of ZnO-NPs at environmental relevant conditions. The surface chemistry and particle size distribution (PSD) of ZnO-NPs with and without the existence of HBCD, HA and electrolytes (NaCl, CaCl2 and MgCl2) after different periods (1 and 3 weeks) were investigated at pH 7.00 ± 0.02. The size of the ZnO-NPs increased from nanometres to micrometres with the addition of numerous concentrations of HBCD, HA, and cations and their mixtures. The zeta potential of ZnO-NPs increased upon addition of HBCD, HA and electrolytes indicating a more stable agglomeration form while less agglomeration was observed in the ZnO-NPs and HA suspension after 3 weeks. Hydrophobic and electrostatic interactions, van der Waals forces, including hydrogen bonding and cation bridging could be potential interactive driving forces. The results indicated agglomeration of ZnO-NPs in the existence of organic substances, salts and contaminants, thus sedimentation and precipitation are promising under salty surface water/sea water.

DOI 10.1016/j.eti.2021.102078
Citations Scopus - 7Web of Science - 1
Co-authors Cheng Fang, Yanju Liu
2021 Biswas B, Naidu R, 'Highly stable and nontoxic lanthanum-treated activated palygorskite for the removal of lake water phosphorus', Processes, 9 (2021) [C1]

Nutrient pollution of surface water, such as excess phosphate loading on lake surface water, is a significant issue that causes ecological and financial damage. Despite many techn... [more]

Nutrient pollution of surface water, such as excess phosphate loading on lake surface water, is a significant issue that causes ecological and financial damage. Despite many technologies that can remove available phosphate, such as material-based adsorption of those available phosphate ions, the development of a material that can trap them from the surface water is worth doing, considering other aspects. These aspects are: (i) efficient adsorption by the material while it settles down to the water column, and (ii) the material itself is not toxic to the lake natural microorganism. Considering these aspects, we developed a trace lanthanum-grafted surface-modified palygorskite, a fibrous clay mineral. It adsorbed a realistic amount of phosphate from the lake water (typically 0.13¿0.22 mg/L). The raw and modified palygorskite (Pal) includes unmodified Australian Pal, heated (at ~400¿ C) Pal, and acid (with 3 M HCl)-treated Pal. Among them, while acid-treated Pal grafted a lower amount of La, it had a higher adsorption capacity (1.243 mg/g) and a quicker adsorption capacity in the time it took to travel to the bottom of the lake (97.6% in 2 h travel time), indicating the adsorption role of both La and clay mineral. The toxicity of these materials was recorded null, and in some period of the incubation of the lake microorganism with the material mixture, La-grafted modified clays increased microbial growth. As a total package, while a high amount of La on the already available material could adsorb a greater amount of phosphate, in this study a trace amount of La on modified clays showed adsorption effectiveness for the realistic amount of phosphate in lake water without posing added toxicity.

DOI 10.3390/pr9111960
Citations Scopus - 1Web of Science - 1
Co-authors Bhaba Biswas
2021 Fang C, Luo Y, Zhang X, Zhang H, Nolan A, Naidu R, 'Identification and visualisation of microplastics via PCA to decode Raman spectrum matrix towards imaging', CHEMOSPHERE, 286 (2021) [C1]
DOI 10.1016/j.chemosphere.2021.131736
Citations Scopus - 49Web of Science - 27
Co-authors Cheng Fang
2021 Basak BB, Sarkar B, Naidu R, 'Environmentally safe release of plant available potassium and micronutrients from organically amended rock mineral powder', ENVIRONMENTAL GEOCHEMISTRY AND HEALTH, 43 3273-3286 (2021) [C1]
DOI 10.1007/s10653-020-00677-1
Citations Scopus - 19Web of Science - 15
2021 Bolan S, Seshadri B, Grainge I, Talley NJ, Naidu R, 'Gut microbes modulate bioaccessibility of lead in soil', Chemosphere, 270 (2021) [C1]

Metabolic uptake of lead (Pb) is controlled by its bioaccessibility. Most studies have examined bioaccessibility of Pb in the absence of gut microbes, which play an important role... [more]

Metabolic uptake of lead (Pb) is controlled by its bioaccessibility. Most studies have examined bioaccessibility of Pb in the absence of gut microbes, which play an important role in the metabolic uptake of nutrients and metal(loid)s in intestine. In this study, we examined the effect of three gut microbes, from various locations in the gut, on the bioaccessibility of soil ingested Pb. The gut microbes include Lactobacillus acidophilus, Lactobacillus rhamnosus and Escherichia coli. Lead toxicity to these three microbes was also examined at various pH values. Bioaccessibility of Pb was measured using gastric and intestinal extractions. Both Pb spiked and Pb-contaminated shooting range field soils were used to measure Pb bioaccessibility in the presence and absence of gut microbes. The results indicated that Pb toxicity to gut microbes, as measured by LD50 value, decreased with increasing pH, and was higher for Lactobacillus species. Gut microbes decreased the bioaccessible Pb; the effect was more pronounced at low pH, mimicking gastric conditions than in conditions closer to the intestine. Lead adsorption by these microbes increased at the higher pH tested, and E. coli adsorbed higher amounts of Pb than did the Lactobacillus species. The effect of gut microbes on reducing Pb bioaccessibility may be attributed to microbially-induced immobilization of Pb through adsorption, precipitation, and complexation reactions. The study demonstrates that bioaccessibility and subsequently bioavailability of metal(loid)s can be modulated by gut microbes, and it is important to undertake bioaccessibility measurements in the presence of gut microbes.

DOI 10.1016/j.chemosphere.2020.128657
Citations Scopus - 9Web of Science - 8
Co-authors Nicholas Talley, Ian Grainge
2021 Abbasi S, Lamb DT, Kader M, Naidu R, Megharaj M, 'The influence of long-term ageing on arsenic ecotoxicity in soil', Journal of Hazardous Materials, 407 (2021) [C1]

The ageing of a contaminant in soil influences the bioavailability and toxicity of environmental pollutants. Yet, despite arsenic (As) being an important terrestrial contaminant, ... [more]

The ageing of a contaminant in soil influences the bioavailability and toxicity of environmental pollutants. Yet, despite arsenic (As) being an important terrestrial contaminant, the effect of As ageing on phytotoxicity has received relatively little research. Research to date has reported predominantly short term (< 0.5 years) experiments. Here, we studied the influence of ageing over 0.25 and 5 years on the phytotoxicity of As (as arsenate) on Cucumis sativus L. (cucumber). The study showed that increasing ageing time of As from 0.25 to 5 years increased the EC10 and EC50 values by 4.0 and 1.76 fold, respectively. The dependence of ageing on soil properties was also examined, although only Freundlich sorption parameters were correlated to the ageing factor (r = 0.68, P = 0.028). Soils with high adsorption capacity also showed the greatest change in toxicity over 5 years. In addition, data was compiled from relevant literature to develop a model for As ecotoxicity. The combined model (n = 54) showed no relationship with pH but was correlated to the oxalate extractable iron content and %clay. Arsenate ecotoxicity (EC50, mg/kg) in the multivariate model was related to oxalate iron content, %clay and ageing time. Thus, the results of this study have significant implications for risk assessment of long-term As contaminated soils.

DOI 10.1016/j.jhazmat.2020.124819
Citations Scopus - 17Web of Science - 9
Co-authors Megh Mallavarapu
2021 Arachchige Chamila Samarasinghe SV, Krishnan K, Aitken RJ, Naidu R, Megharaj M, 'Persistence of the parabens in soil and their potential toxicity to earthworms', ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY, 83 (2021) [C1]
DOI 10.1016/j.etap.2020.103574
Citations Scopus - 15Web of Science - 7
Co-authors Megh Mallavarapu, John Aitken, Chamila Samarasinghe
2021 Islam MR, Sanderson P, Naidu R, Payne TE, Johansen MP, Bari ASMF, Rahman MM, 'Beryllium in contaminated soils: Implication of beryllium bioaccessibility by different exposure pathways', JOURNAL OF HAZARDOUS MATERIALS, 421 (2021) [C1]
DOI 10.1016/j.jhazmat.2021.126757
Citations Scopus - 13Web of Science - 9
Co-authors Mahmud Rahman, Mdrashidul Islam
2021 Lamb D, Choppala G, Yeasmin M, Abbasi S, Wang L, Naidu R, et al., 'Are root elongation assays suitable for establishing metallic anion ecotoxicity thresholds?', Journal of Hazardous Materials Letters, 2 (2021) [C1]
DOI 10.1016/j.hazl.2021.100024
Citations Scopus - 2Web of Science - 2
Co-authors Girish Choppala, Liang Wang
2021 Fang C, Sobhani Z, Zhang D, Zhang X, Gibson CT, Tang Y, et al., 'Capture and characterisation of microplastics printed on paper via laser printer's toners', Chemosphere, 281 (2021) [C1]

Microplastics are among the ubiquitous contaminants in our environment. As emerging contaminants, microplastics are still facing with lots of challenges on the characterisation, i... [more]

Microplastics are among the ubiquitous contaminants in our environment. As emerging contaminants, microplastics are still facing with lots of challenges on the characterisation, including their capture, identification and visualisation, particularly from a complex background. For example, when we print documents using a laser printer, we are printing microplastics onto paper, because the plastics are the main ingredient of the toner powder mixture. Characterisation of these microplastic mixture meets an even more complicated challenge, because plastic's signals might be shielded by other toner powder ingredients such as the pigments, the dyes, the black carbon, and the paper fabrics as well. To solve this challenge, we employ various techniques, including SEM, TEM, XPS, FT-IR, TGA and Raman, to characterise the microplastics printed via the toner powders. Interestingly, we show that Raman can distinguish and visualise the distribution of the microplastics from the complex background of the mixture. We estimate the millions of toner powders, each of which is ~4¿6 µm in size, are printed out per A4 sheet as microplastics. The findings send a strong warning that millions of microplastics might be generated from the printing activities in our daily lives.

DOI 10.1016/j.chemosphere.2021.130864
Citations Scopus - 14Web of Science - 8
Co-authors Zahra Sobhani, Megh Mallavarapu, Cheng Fang
2021 Bhattacharjya S, Sahu A, Phalke DH, Manna MC, Thakur JK, Mandal A, et al., 'In situ decomposition of crop residues using lignocellulolytic microbial consortia: a viable alternative to residue burning', Environmental Science and Pollution Research, 28 32416-32433 (2021) [C1]

Open field burning of crop residue causes severe air pollution and greenhouse gas emission contributing to global warming. In order to seek an alternative, the current study was i... [more]

Open field burning of crop residue causes severe air pollution and greenhouse gas emission contributing to global warming. In order to seek an alternative, the current study was initiated to explore the prospective of lignocellulolytic microbes to expedite in situ decomposition of crop residues. Field trials on farmers¿ field were conducted in the state of Haryana and Maharashtra, to target the burning of rice and wheat residue and sugarcane trash, respectively. A comparative study among crop residue removal (CRR), crop residue burning (CRB) and in situ decomposition of crop residues (IND) revealed that IND of rice and wheat residues took 30¿days whereas IND of sugarcane trash took 45¿days. The decomposition status was assessed by determining the initial and final lignin to cellulose ratio which increased significantly from 0.23 to 0.25, 0.21 to 0.23 and 0.24 to 0.27 for rice, wheat residues and sugarcane trash, respectively. No yield loss was noticed in IND for both rice-wheat system and sugarcane-based system; rather IND showed relatively better crop yield as well as soil health parameters than CRB and CRR. Furthermore, the environmental impact assessment of residue burning indicated a substantial loss of nutrients (28¿31, 23¿25 and 51¿77¿kg¿ha-1 of N+P2O5+K2O for rice, wheat and sugarcane residue) as well as the emission of pollutants to the atmosphere. However, more field trials, as well as refinement of the technology, are warranted to validate and establish the positive potential of in situ decomposition of crop residue to make it a successful solution against the crop residue burning.

DOI 10.1007/s11356-021-12611-8
Citations Scopus - 10Web of Science - 14
Co-authors Mahmud Rahman
2021 Liu W, Yang X, Duan L, Naidu R, Yan K, Liu Y, et al., 'Variability in plant trace element uptake across different crops, soil contamination levels and soil properties in the Xinjiang Uygur Autonomous Region of northwest China', Scientific Reports, 11 (2021) [C1]

This study investigated contamination status of eight trace elements (As, Cd, Cr, Hg, Pb, Cu, Zn and Ni) in farmland soils and crops at 535 sites across the Xinjiang Uygur Autonom... [more]

This study investigated contamination status of eight trace elements (As, Cd, Cr, Hg, Pb, Cu, Zn and Ni) in farmland soils and crops at 535 sites across the Xinjiang Uygur Autonomous Region, Northwest China. Land use types of the sampling sites included vegetable patch, grain field and orchard. Our experimental results indicated all farmland soils were considered as trace element contamination based on the Nemerow comprehensive pollution index (NCPI > 1). However, 91.97% of the crop samples were uncontaminated according to the Chinese Risk Control Standard. Soils from the vegetable patch showed higher pollution level comparison with that from grain field and orchard. Health risks for both non-carcinogenic and carcinogenic risks were calculated through crop ingestion exposure pathway. Grain samples showed highest health risks, followed by melon and fruit, and vegetables. The health risks of crops were mainly driven by Cr and Cd. Crop consumption may pose risks for children but not adults. The source of trace element contamination in the different farmland soils varied and may be attributed to the different agricultural activities. Plant type had a greater influence on the trace element accumulation in crops compared with soil trace element contents and physicochemical properties.

DOI 10.1038/s41598-021-81764-w
Citations Scopus - 15Web of Science - 7
Co-authors Yanju Liu
2021 Umeh AC, Naidu R, Shilpi S, Boateng EB, Rahman A, Cousins IT, et al., 'Sorption of PFOS in 114 Well-Characterized Tropical and Temperate Soils: Application of Multivariate and Artificial Neural Network Analyses', Environmental Science and Technology, 55 1779-1789 (2021) [C1]

The influence of soil properties on PFOS sorption are not fully understood, particularly for variable charge soils. PFOS batch sorption isotherms were conducted for 114 temperate ... [more]

The influence of soil properties on PFOS sorption are not fully understood, particularly for variable charge soils. PFOS batch sorption isotherms were conducted for 114 temperate and tropical soils from Australia and Fiji, that were well-characterized for their soil properties, including total organic carbon (TOC), anion exchange capacity, and surface charge. In most soils, PFOS sorption isotherms were nonlinear. PFOS sorption distribution coefficients (Kd) ranged from 5 to 229 mL/g (median: 28 mL/g), with 63% of the Fijian soils and 35% of the Australian soils showing Kd values that exceeded the observed median Kd. Multiple linear regression showed that TOC, amorphous aluminum and iron oxides contents, anion exchange capacity, pH, and silt content, jointly explained about 53% of the variance in PFOS Kd in soils. Variable charge soils with net positive surface charges, and moderate to elevated TOC content, generally displayed enhanced PFOS sorption than in temperate or tropical soils with TOC as the only sorbent phase, especially at acidic pH ranges. For the first time, two artificial neural networks were developed to predict the measured PFOS Kd (R2 = 0.80) in the soils. Overall, both TOC and surface charge characteristics of soils are important for describing PFOS sorption.

DOI 10.1021/acs.est.0c07202
Citations Scopus - 30Web of Science - 16
Co-authors Sreenivasulu Chadalavada, Anthony Umeh
2021 Khodabakhshloo N, Biswas B, Moore F, Du J, Naidu R, 'Organically functionalized bentonite for the removal of perfluorooctane sulfonate, phenanthrene and copper mixtures from wastewater', APPLIED CLAY SCIENCE, 200 (2021) [C1]
DOI 10.1016/j.clay.2020.105883
Citations Scopus - 17Web of Science - 10
Co-authors Bhaba Biswas
2021 Bagherifam S, Brown TC, Wijayawardena A, Naidu R, 'The influence of different antimony (Sb) compounds and ageing on bioavailability and fractionation of antimony in two dissimilar soils', ENVIRONMENTAL POLLUTION, 270 (2021) [C1]
DOI 10.1016/j.envpol.2020.116270
Citations Scopus - 14Web of Science - 9
Co-authors Ayanka Wijayawardena
2021 Rahman MM, Alauddin M, Alauddin ST, Siddique AB, Islam MR, Agosta G, et al., 'Bioaccessibility and speciation of arsenic in children's diets and health risk assessment of an endemic area in Bangladesh', Journal of Hazardous Materials, 403 (2021) [C1]
DOI 10.1016/j.jhazmat.2020.124064
Citations Scopus - 9Web of Science - 6
Co-authors Mdrashidul Islam, Mahmud Rahman
2021 Naidu R, Biswas B, Willett IR, Cribb J, Kumar Singh B, Paul Nathanail C, et al., 'Chemical pollution: A growing peril and potential catastrophic risk to humanity', Environment International, 156 (2021) [C1]

Anthropogenic chemical pollution has the potential to pose one of the largest environmental threats to humanity, but global understanding of the issue remains fragmented. This art... [more]

Anthropogenic chemical pollution has the potential to pose one of the largest environmental threats to humanity, but global understanding of the issue remains fragmented. This article presents a comprehensive perspective of the threat of chemical pollution to humanity, emphasising male fertility, cognitive health and food security. There are serious gaps in our understanding of the scale of the threat and the risks posed by the dispersal, mixture and recombination of chemicals in the wider environment. Although some pollution control measures exist they are often not being adopted at the rate needed to avoid chronic and acute effects on human health now and in coming decades. There is an urgent need for enhanced global awareness and scientific scrutiny of the overall scale of risk posed by chemical usage, dispersal and disposal.

DOI 10.1016/j.envint.2021.106616
Citations Scopus - 168Web of Science - 59
Co-authors John Aitken, Bhaba Biswas
2021 Baek K, Alessi DS, Naidu R, 'Preface - Recent advances in cleanup of contaminated sites', JOURNAL OF SOILS AND SEDIMENTS, 21 2731-2731 (2021)
DOI 10.1007/s11368-021-03020-y
2021 Rathnayake IVN, Megharaj M, Naidu R, 'Green fluorescent protein based whole cell bacterial biosensor for the detection of bioavailable heavy metals in soil environment', Environmental Technology and Innovation, 23 (2021) [C1]

A Green fluorescent protein (GFP) based whole cell bacterial biosensor was prepared using a bacterial strain sensitive to several heavy metals in order to detect bioavailable heav... [more]

A Green fluorescent protein (GFP) based whole cell bacterial biosensor was prepared using a bacterial strain sensitive to several heavy metals in order to detect bioavailable heavy metals in soils. The transformant, named as Bacillus megaterium VR1 was immobilized in silica matrix using sol¿gel technology, and optimized for its effective pH range, cell density, exposure time, and storage stability. The lowest detection limit (LOD) for each metal was also determined. The pH range for the bacterial strain was found to be between pH 5¿8.5. The optimum exposure time for the transformed bacterial strain to respond to the lowest tested concentration of heavy metal at 25% of inhibition compared to the control was determined as 4 h, 4 h, and 7 h, for Cd, Cu and Zn, respectively. SiNa/LUDOX 1/1 was selected as the optimum immobilization matrix. Storage up to 2 weeks did not show any reduction in the fluorescence in all the matrices. The linear range of the whole cell bacterial biosensor was determined as 0-10; 0¿20 and 0¿100 mg/L for Cd, Cu and Zn respectively. The lowest detection limit was determined as 1.42 × 10-4, 3.16 × 10-4, and 2.42 × 10-4 mg/L for Cd, Cu and Zn, respectively.

DOI 10.1016/j.eti.2021.101785
Citations Scopus - 19Web of Science - 8
Co-authors Megh Mallavarapu
2021 Gao Y, Du J, Bahar MM, Wang H, Subashchandrabose S, Duan L, et al., 'Metagenomics analysis identifies nitrogen metabolic pathway in bioremediation of diesel contaminated soil', Chemosphere, 271 (2021) [C1]

Nitrogen amendment is known to effectively enhance the bioremediation of hydrocarbon-contaminated soil, but the nitrogen metabolism in this process is not well understood. To unra... [more]

Nitrogen amendment is known to effectively enhance the bioremediation of hydrocarbon-contaminated soil, but the nitrogen metabolism in this process is not well understood. To unravel the nitrogen metabolic pathway(s) of diesel contaminated soil, six types of nitrogen sources were added to the diesel contaminated soil. Changes in microbial community and soil enzyme genes were investigated by metagenomics analysis and chemical analysis through a 30-day incubation study. The results showed that ammonium based nitrogen sources significantly accelerated the degradation of total petroleum hydrocarbon (TPH) (79¿81%) compared to the control treatment (38%) and other non-ammonium based nitrogen amendments (43¿57%). Different types of nitrogen sources could dramatically change the microbial community structure and soil enzyme gene abundance. Proteobacteria and Actinobacteria were identified as the two dominant phyla in the remediation of diesel contaminated soil. Metagenomics analysis revealed that the preferred metabolic pathway of nitrogen was from ammonium to glutamate via glutamine, and the enzymes governing this transformation were glutamine synthetase and glutamate synthetase; while in nitrate based amendment, the conversion from nitrite to ammonium was restrained by the low abundance of nitrite reductase enzyme and therefore retarded the TPH degradation rate. It is concluded that during the process of nitrogen enhanced bioremediation, the most efficient nitrogen cycling direction was from ammonium to glutamine, then to glutamate, and finally joined with carbon metabolism after transforming to 2-oxoglutarate.

DOI 10.1016/j.chemosphere.2021.129566
Citations Scopus - 27Web of Science - 11
Co-authors Yanju Liu, Mezbaul Bahar, Megh Mallavarapu, Suresh Subashchandrabose
2021 Islam MR, Sanderson P, Johansen MP, Payne TE, Naidu R, 'The influence of soil properties on sorption-desorption of beryllium at a low level radioactive legacy waste site', Chemosphere, 268 (2021) [C1]

This study examined the influence of soil physicochemical properties on the sorption, desorption and kinetics of beryllium (Be) uptake and release on soils from a legacy waste sit... [more]

This study examined the influence of soil physicochemical properties on the sorption, desorption and kinetics of beryllium (Be) uptake and release on soils from a legacy waste site in Australia. This information is needed to help explain the current distribution of Be at the site and evaluate potential future environmental risks. Sorption was determined by a batch study and key soil properties were assessed to explain Be retention. The soil was favourable for sorption of Be (up to 99%) due to organic content, negative surface charge, soil oxyhydroxides (Fe/Al/Mn¿O/OH) and the porosity of the soil structure. Lesser sorption was observed in the presence of a background electrolyte (NaNO3). Sorption closely followed pseudo second order kinetics and was best described by the Langmuir model. FTIR analysis suggested that chemisorption was the predominant mechanism of Be sorption. Desorption was very low and best described by the Freundlich model. The low desorption reflected the high Kd (up to 6624 L/kg), and the presence of hysteresis suggested partially irreversible binding of Be with active surfaces of the soil matrix (minerals, SOM, oxyhydroxides of Fe/Al/Mn etc.). Intra-particle diffusion of Be and entrapment in the pores contribute to the irreversible binding. The sorption behaviour of Be helped to explain the relative immobility of Be at the site despite the significant quantities of Be disposed. Soil physicochemical properties were significant for Be sorption, through influencing both the uptake and desorption, and this demonstrates the implications of these measurements for evaluating potential future risks to the environment.

DOI 10.1016/j.chemosphere.2020.129338
Citations Scopus - 11Web of Science - 7
Co-authors Mdrashidul Islam
2021 Unnithan A, Bekele DN, Chadalavada S, Naidu R, 'Insights into vapour intrusion phenomena: Current outlook and preferential pathway scenario', Science of the Total Environment, 796 (2021) [C1]

Vapour intrusion (VI) is the phenomenon by which volatile organic compounds (VOCs) migrate from the subsurface source through the soil and enter into the overlying buildings, affe... [more]

Vapour intrusion (VI) is the phenomenon by which volatile organic compounds (VOCs) migrate from the subsurface source through the soil and enter into the overlying buildings, affecting the indoor air quality and ultimately causing health hazards to the occupants. Health risk assessments associated with hydrocarbon contaminated sites and recommendations of site closure are often made by quantifying the VI risks using mathematical models known as ¿vapour intrusion models¿ (VIM). In order to predict the health risk, various factors such as the lithological and geochemical conditions of the subsurface, environmental conditions, building operational conditions etc. are commonly evaluated using VIMs. Use of these models can overlook the role of preferential pathways like highly permeable subsurface layers and utility lines which act as the path of least resistance for vapour transport, which can increase the VI risks. The extensive networks of utility lines and sanitary sewer systems in urban areas can significantly exacerbate the uncertainty of VI investigations. The backfill materials like sand and gravel surrounding the utility lines can allow the vapours to easily pass through due to their high porosity as compared to natural formations. Hence, failure to understand the role of preferential pathways on the fate and transport of VOC in the vadose zone can result in more conservative predictions of indoor air vapour concentrations and wrong clean up approaches. This comprehensive review outlines the vapour transport mechanisms, factors influencing VI, VIMs and the role of preferential pathways in predicting indoor air vapour concentrations.

DOI 10.1016/j.scitotenv.2021.148885
Citations Scopus - 8Web of Science - 3
Co-authors Dawit Bekele, Sreenivasulu Chadalavada
2021 Bolan S, Seshadri B, Keely S, Kunhikrishnan A, Bruce J, Grainge I, et al., 'Bioavailability of arsenic, cadmium, lead and mercury as measured by intestinal permeability', Scientific Reports, 11 (2021) [C1]

In this study, the intestinal permeability of metal(loid)s (MLs) such as arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) was examined, as influenced by gut microbes and che... [more]

In this study, the intestinal permeability of metal(loid)s (MLs) such as arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) was examined, as influenced by gut microbes and chelating agents using an in vitro gastrointestinal/Caco-2 cell intestinal epithelium model. The results showed that in the presence of gut microbes or chelating agents, there was a significant decrease in the permeability of MLs (As-7.5%, Cd-6.3%, Pb-7.9% and Hg-8.2%) as measured by apparent permeability coefficient value (Papp), with differences in ML retention and complexation amongst the chelants and the gut microbes. The decrease in ML permeability varied amongst the MLs. Chelating agents reduce intestinal absorption of MLs by forming complexes thereby making them less permeable. In the case of gut bacteria, the decrease in the intestinal permeability of MLs may be associated to a direct protection of the intestinal barrier against the MLs or indirect intestinal ML sequestration by the gut bacteria through adsorption on bacterial surface. Thus, both gut microbes and chelating agents can be used to decrease the intestinal permeability of MLs, thereby mitigating their toxicity.

DOI 10.1038/s41598-021-94174-9
Citations Scopus - 11Web of Science - 4
Co-authors Simon Keely, Nicholas Talley, Ian Grainge
2021 Al Amin M, Luo Y, Nolan A, Robinson F, Niu J, Warner S, et al., 'Total oxidisable precursor assay towards selective detection of PFAS in AFFF', Journal of Cleaner Production, 328 (2021) [C1]

Total oxidisable precursor assay (TOP assay) can degrade and convert ¿unknown¿ per- and polyfluoroalkyl substances (PFAS) to detectable PFAS. However, the detailed degradation pat... [more]

Total oxidisable precursor assay (TOP assay) can degrade and convert ¿unknown¿ per- and polyfluoroalkyl substances (PFAS) to detectable PFAS. However, the detailed degradation pathway is still not known, particularly when the TOP assay is applied to analyse complex samples such as aqueous film-forming foam (AFFF). To gain insights into the pathway and the effectiveness of the TOP assay, several ¿known¿ compounds are first tested as controls, including sodium dodecyl benzene sulphate (SDBS), perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS). Secondly, the test is expanded to several PFAS precursors such as 6:2 fluorotelomer sulfonate (6:2 FTS), 8:2 fluorotelomer sulfonate (8:2 FTS), and a cationic surfactant N-ethyl-N-(2-hydroxyethyl) perfluorooctyl sulfonamide (EtFOSE). Thirdly, the TOP assay is used to test ¿unknown¿ PFAS samples that have been previously used as AFFF in Australia. The degradation products are monitored, to compare the mass balance and propose the degradation pathway. While HPLC-MS/MS is typically employed to detect the individual TOP assay products, most of which are perfluoroalkyl carboxylic acids (PFCA), an app-based smartphone sensor can also provide semi-quantitative results as a sum. Overall, the results indicate the effectiveness of the TOP assay to assess the presence of PFAS precursors in the AFFF samples, with some variations in the end products. Recommendations for enhancement of the TOP assay are also provided.

DOI 10.1016/j.jclepro.2021.129568
Citations Scopus - 12Web of Science - 3
Co-authors Cheng Fang, Megh Mallavarapu, Yanju Liu
2021 Siddique AB, Rahman MM, Islam MR, Naidu R, 'Varietal variation and formation of iron plaques on cadmium accumulation in rice seedling', Environmental Advances, 5 (2021) [C1]

This study examined the impact of iron (Fe) plaque deposition and varietal variation on cadmium (Cd) accumulation in the rice plants (Oryza sativa L.) in a hydroponic experiment u... [more]

This study examined the impact of iron (Fe) plaque deposition and varietal variation on cadmium (Cd) accumulation in the rice plants (Oryza sativa L.) in a hydroponic experiment under controlled conditions. Fe was applied at the rate of 0, 50 and 100 mg L-1 to the nutrient solution to generate varying amounts of Fe plaque deposition around the root of the rice seedlings. The seedlings were then treated with Cd at the rate of 0, 0.5 and 1.0 mg L-1 in the nutrient solution. Reddish-brown colored Fe plaque is induced gradually on the roots of rice seedlings after Fe supplementation in the nutrient solution. Results showed that the biomass production differed markedly among the rice varieties due to the application of Fe with or without Cd stress. The Quest variety demonstrated the highest capacity of Fe plaque formation compared to the other varieties. The application of Fe and Cd significantly affected the Cd concentration in the citrate-bicarbonate-dithionite (CBD) extracts of roots and in the rice seedlings. The exogenous application of Cd significantly increased the root Cd content, which was greater than the shoot Cd content. The Fe plaque deposition capacity markedly varied among the examined varieties. The Cd concentrations in shoots declined by adding Fe. This study results demonstrated that boosted Fe plaque formation can minimize detrimental effects of Cd on rice shoot growth to some extent, but the root tissues are the main barrier to Cd accumulation and movements in the interior of the rice plants.

DOI 10.1016/j.envadv.2021.100075
Citations Scopus - 14
Co-authors Mahmud Rahman
2021 Murtaza G, Rehman MZ, Qadir M, Shehzad MT, Zeeshan N, Ahmad HR, et al., 'High residual sodium carbonate water in the Indian subcontinent: concerns, challenges and remediation', INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY, 18 3257-3272 (2021) [C1]
DOI 10.1007/s13762-020-03066-4
Citations Scopus - 7Web of Science - 2
2021 Uz-Zaman KA, Biswas B, Rahman MM, Naidu R, 'Smectite-supported chain of iron nanoparticle beads for efficient clean-up of arsenate contaminated water', Journal of Hazardous Materials, 407 (2021) [C1]

Prolonged exposure to inorganic arsenic (As) via drinking water is a major concern as it poses significant human health risks. Removal of As is crucial but requires effective and ... [more]

Prolonged exposure to inorganic arsenic (As) via drinking water is a major concern as it poses significant human health risks. Removal of As is crucial but requires effective and environment-friendly clean-up technology to avoid any additional risk to the environment. In this study, we developed Australian smectite (smec)-supported nano zero-valent iron (nZVI) composite for arsenate i.e., As(V) sorption. We used a range of tools, including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and energy dispersion X-ray (EDS) spectroscopy to characterise the material. SEM and TEM images and elemental mapping of the composite reflect that the smectite layer was surrounded by a chain of iron nanobeads evenly distributed on clay particles, which is quite exceptional among currently available nZVIs. The maximum As(V) sorption capacity of this composite was 23.12 mg/g in the ambient conditions. Using X-ray photoelectron spectroscopy we unveiled chemical states of As and Fe before and after the sorption process. Additionally, the release of iron nanoparticles from the composite at various pHs (3-10) were found negligible, which demonstrates the effectiveness of smec-nZVI to remove As(V) from contaminated water without posing any secondary pollutant.

DOI 10.1016/j.jhazmat.2020.124396
Citations Scopus - 11Web of Science - 5
Co-authors Bhaba Biswas, Mahmud Rahman
2021 Zhang J, Wu S, Xu J, Liang P, Wang M, Naidu R, et al., 'Comparison of ashing and pyrolysis treatment on cadmium/zinc hyperaccumulator plant: Effects on bioavailability and metal speciation in solid residues and risk assessment', Environmental Pollution, 272 (2021) [C1]

Phytoremediation of metal(loid)s contaminated sites is widely used, while there is scarce of investigation on the metal-enriched biomass waste safely disposal which resulted in ri... [more]

Phytoremediation of metal(loid)s contaminated sites is widely used, while there is scarce of investigation on the metal-enriched biomass waste safely disposal which resulted in risks of causing secondary pollution to the soil and water bodies and even to human health. Thus, this study compared the effects of ashing and pyrolysis treatments on cadmium (Cd) and zinc (Zn) hyperaccumulation plant Sedum plumbizincicola. Chemical speciation, the Toxicity Characteristic Leaching Procedure (TCLP), and diethylenetriamine pentaacetic acid (DTPA) extraction were employed to characterize the bioavailability and leachability of Cd and Zn in the solid residues after pyrolysis and ashing. The risk assessment code (RAC) and potential ecological risk index (RI) were subsequently used to evaluate the risk of the solid residues to the environment. The results showed that both ashing and pyrolysis treatments could transform the bioavailable Cd and Zn in S. plumbizincicola into a more stable form, and the higher the temperature the greater the stablility. Pyrolysis converted a maximum of 80.0% of Cd and 70.3% of Zn in S. plumbizincicola to the oxidisable and residual fractions, compared with ashing which achieved only a ~42% reduction. The pyrolysis process minimised the risk level of Cd and Zn to the environment based on the RAC and RI assessments. The results of the TCLP test, and DTPA extraction confirmed that the leaching rate and the bioavailable portion of Cd and Zn in the biochars produced by pyrolysis were invariably significantly (p < 0.05) lower than the solid residues produced by ashing, and reached the lowest at 650 °C. In other words, pyrolysis was better than ashing for thermal treatment of the metal-enriched hyperaccumulator plant, in view of minimising the bioavailability and leachability of Cd and Zn from the solid residues to the environment. This study provides fundamental data on the choice of treatments for the disposal of metal-enriched plant biomass.

DOI 10.1016/j.envpol.2020.116039
Citations Scopus - 21Web of Science - 11
Co-authors Yanju Liu
2021 Rahman MA, Lamb D, Rahman MM, Bahar MM, Sanderson P, Abbasi S, et al., 'Removal of arsenate from contaminated waters by novel zirconium and zirconium-iron modified biochar', Journal of Hazardous Materials, 409 (2021) [C1]
DOI 10.1016/j.jhazmat.2020.124488
Citations Scopus - 78Web of Science - 47
Co-authors Mahmud Rahman, Mezbaul Bahar
2021 Sobhani Z, Luo Y, Gibson CT, Tang Y, Naidu R, Megharaj M, Fang C, 'Collecting Microplastics in Gardens: Case Study (i) of Soil', Frontiers in Environmental Science, 9 (2021) [C1]

As an emerging contaminant, microplastic is receiving increasing attention. However, the contamination source is not fully known, and new sources are still being identified. Herew... [more]

As an emerging contaminant, microplastic is receiving increasing attention. However, the contamination source is not fully known, and new sources are still being identified. Herewith, we report that microplastics can be found in our gardens, either due to the wrongdoing of leaving plastic bubble wraps to be mixed with mulches or due to the use of plastic landscape fabrics in the mulch bed. In the beginning, they were of large sizes, such as > 5¿mm. However, after 7 years in the garden, owing to natural degradation, weathering, or abrasion, microplastics are released. We categorize the plastic fragments into different groups, 5¿mm¿0.75¿mm, 0.75¿mm¿100¿µm, and 100¿0.8¿µm, using filters such as kitchenware, meaning we can collect microplastics in our gardens by ourselves. We then characterized the plastics using Raman image mapping and a logic-based algorithm to increase the signal-to-noise ratio and the image certainty. This is because the signal-to-noise ratio from a single Raman spectrum, or even from an individual peak, is significantly less than that from a spectrum matrix of Raman mapping (such as 1 vs. 50 × 50) that contains 2,500 spectra, from the statistical point of view. From the 10¿g soil we sampled, we could detect the microplastics, including large (5¿mm¿100¿µm) fragments and small (<100¿µm) ones, suggesting the degradation fate of plastics in the gardens. Overall, these results warn us that we must be careful when we do gardening, including selection of plastic items for gardens.

DOI 10.3389/fenvs.2021.739775
Citations Scopus - 9Web of Science - 2
Co-authors Megh Mallavarapu, Zahra Sobhani, Cheng Fang
2021 Zhang D, Ding A, Li T, Wu X, Liu Y, Naidu R, 'Immobilization of Cd and Pb in a contaminated acidic soil amended with hydroxyapatite, bentonite, and biochar', JOURNAL OF SOILS AND SEDIMENTS, 21 2262-2272 (2021) [C1]
DOI 10.1007/s11368-021-02928-9
Citations Scopus - 16Web of Science - 12
Co-authors Yanju Liu
2021 Usmani Z, Sharma M, Awasthi AK, Sharma GD, Cysneiros D, Nayak SC, et al., 'Minimizing hazardous impact of food waste in a circular economy Advances in resource recovery through green strategies', Journal of Hazardous Materials, 416 (2021) [C1]

Recent trends in food waste and its management have increasingly started to focus on treating it as a reusable resource. The hazardous impact of food waste such as the release of ... [more]

Recent trends in food waste and its management have increasingly started to focus on treating it as a reusable resource. The hazardous impact of food waste such as the release of greenhouse gases, deterioration of water quality and contamination of land areas are a major threat posed by food waste. Under the circular economy principles, food waste can be used as a sustainable supply of high-value energy, fuel, and nutrients through green techniques such as anaerobic digestion, co-digestion, composting, enzymatic treatment, ultrasonic, hydrothermal carbonization. Recent advances made in anaerobic co-digestion are helping in tackling dual or even multiple waste streams at once with better product yields. Integrated approaches that employ pre-processing the food waste to remove obstacles such as volatile fractions, oils and other inhibitory components from the feedstock to enhance their bioconversion to reduce sugars. Research efforts are also progressing in optimizing the operational parameters such as temperature, pressure, pH and residence time to enhance further the output of products such as methane, hydrogen and other platform chemicals such as lactic acid, succinic acid and formic acid. This review brings together some of the recent progress made in the green strategies towards food waste valorization.

DOI 10.1016/j.jhazmat.2021.126154
Citations Scopus - 43Web of Science - 29
2021 Shahriar S, Haque MM, Naidu R, Rahman MM, 'Concentrations of toxic elements and health risk assessment in arum grown in arsenic-contaminated areas of Bangladesh', Food Control, 129 (2021) [C1]

Arum plant parts such as stem, leaf and corm and the corresponding farm soils were sampled from four As-impacted districts of Bangladesh to assess the potential health risk to hum... [more]

Arum plant parts such as stem, leaf and corm and the corresponding farm soils were sampled from four As-impacted districts of Bangladesh to assess the potential health risk to humans from toxic elements (TEs) including arsenic (As), cadmium (Cd) and lead (Pb). The mean concentrations of As in arum leaf, stem and corm were 150 µg/kg, 107 µg/kg and 101 µg/kg, respectively, whereas mean Cd in arum leaf, stem and corm were 115 µg/kg, 261 µg/kg and 180 µg/kg, respectively and mean Pb in arum leaf, stem and corm were 595 µg/kg, 403 µg/kg and 577 µg/kg, respectively. Daily dietary intake of As, Cd and Pb from sampled arum were 0.003, 0.008 and 0.021 µg/kg bw for adults. As per capita intake of arum is low, hazard quotient (HQ) values for all TEs were found minimal, which reveals no appreciable health risk associated with arum consumption to the local inhabitants.

DOI 10.1016/j.foodcont.2021.108240
Citations Scopus - 6Web of Science - 4
Co-authors Mahmud Rahman
2021 Perera IA, Abinandan S, Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Microalgal-bacterial consortia unveil distinct physiological changes to facilitate growth of microalgae', FEMS Microbiology Ecology, 97 (2021) [C1]

Physiological changes that drive the microalgal-bacterial consortia are poorly understood so far. In the present novel study, we initially assessed five morphologically distinct m... [more]

Physiological changes that drive the microalgal-bacterial consortia are poorly understood so far. In the present novel study, we initially assessed five morphologically distinct microalgae for their ability in establishing consortia in Bold's basal medium with a bacterial strain, Variovorax paradoxus IS1, all isolated from wastewaters. Tetradesmus obliquus IS2 and Coelastrella sp. IS3 were further selected for gaining insights into physiological changes, including those of metabolomes in consortia involving V. paradoxus IS1. The distinct parameters investigated were pigments (chlorophyll a, b, and carotenoids), reactive oxygen species (ROS), lipids and metabolites that are implicated in major metabolic pathways. There was a significant increase (>1.2-fold) in pigments, viz., chlorophyll a, b and carotenoids, decrease in ROS and an enhanced lipid yield (>2-fold) in consortia than in individual cultures. In addition, the differential regulation of cellular metabolites such as sugars, amino acids, organic acids and phytohormones was distinct among the two microalgal-bacterial consortia. Our results thus indicate that the selected microalgal strains, T. obliquus IS2 and Coelastrella sp. IS3, developed efficient consortia with V. paradoxus IS1 by effecting the required physiological changes, including metabolomics. Such microalgal-bacterial consortia could largely be used in wastewater treatment and for production of value-added metabolites.

DOI 10.1093/femsec/fiab012
Citations Scopus - 13Web of Science - 8
Co-authors Megh Mallavarapu, Abinandan Sudharsanam, Suresh Subashchandrabose
2021 Lamb D, Choppala G, Yeasmin M, Abbasi S, Wang L, Naidu R, et al., 'Are root elongation assays suitable for establishing metallic anion ecotoxicity thresholds?', Journal of Hazardous Materials Letters, 2 100024-100024 (2021)
DOI 10.1016/j.hazl.2021.100024
Co-authors Liang Wang, Girish Choppala
2021 Zheng L, Gao Y, Du J, Zhang W, Huang Y, Zhao Q, et al., 'Single and binary adsorption behaviour and mechanisms of cd

The chitosan¿EDTA modified magnetic biochar (E¿CMBC) was successfully used as a novel adsorbent to remove heavy metals. The adsorption behaviour and mechanisms of E¿CMBC to Cd2+, ... [more]

The chitosan¿EDTA modified magnetic biochar (E¿CMBC) was successfully used as a novel adsorbent to remove heavy metals. The adsorption behaviour and mechanisms of E¿CMBC to Cd2+, Cu2+ and Ni2+ were performed in single and binary system in aqueous solutions. In single¿metal system, the adsorption process of Cd2+, Cu2+ and Ni2+ on E¿CMBC fitted well with the Avrami fractional¿order kinetics model and the Langmuir isotherm model. The measured maximum adsorption capacities were 61.08 mg g-1, 48.36 mg g-1 and 41.17 mg g-1 for Cd2+, Cu2+ and Ni2+, respectively. In binary¿metal system, coexisting ions have obvious competitive adsorption behaviour on E¿CMBC when the concentration of heavy meal beyond 20 mg L-1 . The maximum adsorption capacities of the heavy metals were found to be lower than that in single¿metal system. The order of the competitive adsorption ability was Cu2+ > Ni2+ > Cd2+ . Interestingly, in Cd2+¿Cu2+ system the earlier adsorbed Cd2+ could be completely replaced by Cu2+ from the solution. Different competitive adsorption ability of those heavy metal were due to the characteristics of heavy metal and resultant affinity of the adsorption sites on E¿CMBC. The adsorption mechanism indicated that chemical adsorption played a dominating role. Therefore, E¿CMBC could be a potential adsorbent for wastewater treatment.

DOI 10.3390/pr9101829
Citations Scopus - 13Web of Science - 9
Co-authors Yanju Liu
2021 Hassan M, Liu Y, Naidu R, Du J, Qi F, Donne SW, Islam MM, 'Mesoporous Biopolymer Architecture Enhanced the Adsorption and Selectivity of Aqueous Heavy-Metal Ions', ACS Omega, 6 15316-15331 (2021) [C1]

Halloysite nanotubes (HNT) and ball-milled biochar (BC) incorporated biocompatible mesoporous adsorbents (HNT-BC@Alg) were synthesized for adsorption of aqueous heavy-metal ions. ... [more]

Halloysite nanotubes (HNT) and ball-milled biochar (BC) incorporated biocompatible mesoporous adsorbents (HNT-BC@Alg) were synthesized for adsorption of aqueous heavy-metal ions. HNT-BC@Alg outperformed the BC, HNT, and BC@Alg in removing cadmium (Cd), copper (Cu), nickel (Ni), and lead (Pb). Mesoporous structure (?7.19 to 7.56 nm) of HNT-BC@Alg was developed containing an abundance of functional groups induced from encapsulated BC and tubular HNT, which allowed heavy metals to infiltrate and interact with the adsorbents. Siloxane groups from HNT, oxygen-containing functional groups from BC, and hydroxyl and carboxyl groups from alginate polymer play a significant role in the adsorption of heavy-metal ions. The removal percentage of heavy metals was recorded as Pb (?99.97 to 99.05%) > Cu (?95.01 to 90.53%) > Cd (?92.5 to 55.25%) > Ni (?80.85 to 50.6%), even in the presence of 0.01/0.001 M of CaCl2 and Na2SO4 as background electrolytes and charged organic molecule under an environmentally relevant concentration (200 µg/L). The maximum adsorption capacities of Ni, Cd, Cu, and Pb were calculated as 2.85 ± 0.08, 6.96 ± 0.31, 16.87 ± 1.50, and 26.49 ± 2.04 mg/g, respectively. HNT-BC@Alg has fast sorption kinetics and maximum adsorption capacity within a short contact time (?2 h). Energy-dispersive X-ray spectroscopy (EDS) elemental mapping exhibited that adsorbed heavy metals co-distributed with Ca, Si, and Al. The reduction of surface area, pore volume, and pore area of HNT-BC@Alg (after sorption of heavy metals) confirms that mesoporous surface (2-18 nm) supports diffusion, infiltration, and interaction. However, a lower range of mesoporous diameter of the adsorbent is more suitable for the adsorption of heavy-metal ions. The adsorption isotherm and kinetics fitted well with the Langmuir isotherm and the pseudo-second-order kinetic models, demonstrating the monolayer formation of heavy-metal ions through both the physical sorption and chemical sorption, including pore filling, ion exchange, and electrostatic interaction.

DOI 10.1021/acsomega.1c01642
Citations Scopus - 22Web of Science - 9
Co-authors Yanju Liu, Scott Donne
2021 Ramadass K, Kuppusamy S, Venkateswarlu K, Naidu R, Megharaj M, 'Unresolved complex mixtures of petroleum hydrocarbons in the environment: An overview of ecological effects and remediation approaches', Critical Reviews in Environmental Science and Technology, 51 2872-2894 (2021) [C1]

Unresolved complex mixtures (UCMs) of hydrocarbons are the pollutants of serious concern commonly occurring in most of the environments contaminated with petroleum hydrocarbons. U... [more]

Unresolved complex mixtures (UCMs) of hydrocarbons are the pollutants of serious concern commonly occurring in most of the environments contaminated with petroleum hydrocarbons. UCMs constitute a relatively unidentified group of compounds compared to the well-resolved hydrocarbons that could easily be identified by the modern chromatographic methods. UCMs that accumulate in the environment cause several toxicological effects of ecological significance, and indirectly affect the human health. Despite decades-long efforts to provide adequate information in this area of research, the fate and environmental impacts of UCMs of petroleum hydrocarbons are poorly understood. Techniques for extraction and analysis of UCMs in the environment are very important in their identification and quantification. Also, remediation of toxic UCMs of petroleum hydrocarbons is all the more essential. In fact, UCMs are often neglected in the risk assessments due to lack of proper identification methods and toxicity data. This critical review presents an overview of our current knowledge on the environmental occurrence, sources, separation, and identification methods for UCMs. The ecological toxicity of UCMs toward the biota and the strategies for remediation of the environments contaminated with UCMs have also been discussed in detail.

DOI 10.1080/10643389.2020.1813066
Citations Scopus - 2Web of Science - 3
Co-authors Megh Mallavarapu, Kavitha Ramadass
2021 Saini A, Bekele DN, Chadalavada S, Fang C, Naidu R, 'Electrokinetic remediation of petroleum hydrocarbon contaminated soil (I)', Environmental Technology and Innovation, 23 (2021) [C1]

The remediation of petroleum hydrocarbons (TPH) in a contaminated soil by electrokinetic (EK) treatment was studied in the laboratory. The effects of applying a constant electrica... [more]

The remediation of petroleum hydrocarbons (TPH) in a contaminated soil by electrokinetic (EK) treatment was studied in the laboratory. The effects of applying a constant electrical current on soil pH, moisture content, electrical conductivity (EC), temperature, and the concentrations of three fractions of TPH (C10¿C16, C17¿C34 and C35¿C40) were investigated. The experiment was run for seven days and soil samples were collected at the end of the 7 day period for analysis of soil pH and TPH concentration. There were extreme pH conditions near the electrodes. At the end of the experiment there was around a 37% reduction of C10¿C16 chain compounds compared to the initial concentration of 164 ± 18 mg/kg. The study investigated TPH remediation to a depth of 24 cm, which is significantly more than most studies of EK remediation of TPH-contaminated soils. We observed reductions in TPH concentrations even at a depth of 24 cm. The spatial distribution of reductions in TPH concentrations was also studied and it was observed that more remediation occurred near the cathodes than near the anodes. Further, the greatest reductions in TPH concentrations were recorded near the electrodes in the lowest and middle parts of the experimental set-up. The application of electrokinetics to remediate TPH-contaminatedsoils could be a viable option as an in situ remediation technology.

DOI 10.1016/j.eti.2021.101585
Citations Scopus - 14Web of Science - 5
Co-authors Dawit Bekele, Sreenivasulu Chadalavada, Cheng Fang
2020 Besha AT, Liu Y, Fang C, Bekele DN, Naidu R, 'Assessing the interactions between micropollutants and nanoparticles in engineered and natural aquatic environments', Critical Reviews in Environmental Science and Technology, 50 135-215 (2020) [C1]
DOI 10.1080/10643389.2019.1629799
Citations Scopus - 34Web of Science - 29
Co-authors Dawit Bekele, Cheng Fang, Yanju Liu
2020 Sivaram AK, Subashchandrabose SR, Logeshwaran P, Lockington R, Naidu R, Megharaj M, 'Rhizodegradation of PAHs differentially altered by C3 and C4 plants', Scientific Reports, 10 (2020) [C1]
DOI 10.1038/s41598-020-72844-4
Citations Scopus - 21Web of Science - 11
Co-authors Logeshwaran Panneerselvan, Megh Mallavarapu, Suresh Subashchandrabose
2020 Saini A, Bekele DN, Chadalavada S, Fang C, Naidu R, 'A review of electrokinetically enhanced bioremediation technologies for PHs', Journal of Environmental Sciences, 88 31-45 (2020) [C1]
DOI 10.1016/j.jes.2019.08.010
Citations Scopus - 23Web of Science - 12
Co-authors Cheng Fang, Dawit Bekele, Sreenivasulu Chadalavada
2020 Wang L, Cheng Y, Lamb D, Naidu R, 'The application of rapid handheld FTIR petroleum hydrocarbon-contaminant measurement with transport models for site assessment: A case study', Geoderma, 361 (2020) [C1]
DOI 10.1016/j.geoderma.2019.114017
Citations Scopus - 14Web of Science - 13
Co-authors Ying Cheng, Liang Wang
2020 Logeshwaran P, Sivaram AK, Yadav M, Chadalavada S, Naidu R, Megharaj M, 'Phytotoxicity of Class B aqueous firefighting formulations, Tridol S 3 and 6% to Lemna minor', Environmental Technology and Innovation, 18 (2020) [C1]
DOI 10.1016/j.eti.2020.100688
Citations Scopus - 2Web of Science - 1
Co-authors Megh Mallavarapu, Sreenivasulu Chadalavada, Logeshwaran Panneerselvan
2020 Naidu R, Nadebaum P, Fang C, Cousins I, Pennell K, Conder J, et al., 'Per- and poly-fluoroalkyl substances (PFAS): Current status and research needs', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100915
Citations Scopus - 62Web of Science - 32
Co-authors Anthony Umeh, Dawit Bekele, Sreenivasulu Chadalavada, Yanju Liu, Megh Mallavarapu, Bhaba Biswas, Cheng Fang
2020 Sobhani Z, Zhang X, Gibson C, Naidu R, Megharaj M, Fang C, 'Identification and visualisation of microplastics/nanoplastics by Raman imaging (i): Down to 100 nm', Water Research, 174 (2020) [C1]
DOI 10.1016/j.watres.2020.115658
Citations Scopus - 169Web of Science - 104
Co-authors Megh Mallavarapu, Cheng Fang, Zahra Sobhani
2020 Logeshwaran P, Krishnan K, Naidu R, Megharaj M, 'Purification and characterization of a novel fenamiphos hydrolysing enzyme from Microbacterium esteraromaticum MM1', Chemosphere, 252 (2020) [C1]
DOI 10.1016/j.chemosphere.2020.126549
Citations Scopus - 17Web of Science - 8
Co-authors Logeshwaran Panneerselvan, Megh Mallavarapu
2020 Shahriar S, Rahman MM, Naidu R, 'Geographical variation of cadmium in commercial rice brands in Bangladesh: Human health risk assessment', Science of the Total Environment, 716 (2020) [C1]
DOI 10.1016/j.scitotenv.2020.137049
Citations Scopus - 36Web of Science - 24
Co-authors Mahmud Rahman
2020 Biswas B, Juhasz AL, Mahmudur Rahman M, Naidu R, 'Modified clays alter diversity and respiration profile of microorganisms in long-term hydrocarbon and metal co-contaminated soil', Microbial Biotechnology, 13 522-534 (2020) [C1]
DOI 10.1111/1751-7915.13510
Citations Scopus - 9Web of Science - 9
Co-authors Bhaba Biswas, Mahmud Rahman
2020 Nuruzzaman M, Ren J, Liu Y, Rahman MM, Shon HK, Naidu R, 'Hollow Porous Silica Nanosphere with Single Large Pore Opening for Pesticide Loading and Delivery', ACS Applied Nano Materials, 3 105-113 (2020) [C1]
DOI 10.1021/acsanm.9b01769
Citations Scopus - 31Web of Science - 24
Co-authors Yanju Liu, Md Nuruzzaman, Mahmud Rahman
2020 Hassan M, Liu Y, Naidu R, Du J, Qi F, 'Adsorption of Perfluorooctane sulfonate (PFOS) onto metal oxides modified biochar', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100816
Citations Scopus - 59Web of Science - 37
Co-authors Yanju Liu
2020 Sobhani Z, Lei Y, Tang Y, Wu L, Zhang X, Naidu R, et al., 'Microplastics generated when opening plastic packaging', Scientific reports, 10 (2020) [C1]
DOI 10.1038/s41598-020-61146-4
Citations Scopus - 149Web of Science - 74
Co-authors Zahra Sobhani, Cheng Fang, Megh Mallavarapu
2020 Bahar MM, Mahbub KR, Naidu R, Megharaj M, 'A simple spectrophotometric method for rapid quantitative screening of arsenic bio-transforming bacteria', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100840
Citations Scopus - 3Web of Science - 2
Co-authors Megh Mallavarapu, Mezbaul Bahar
2020 Bidast S, Golchin A, Baybordi A, Zamani A, Naidu R, 'The effects of non-stabilised and Na-carboxymethylcellulose-stabilised iron oxide nanoparticles on remediation of Co-contaminated soils', Chemosphere, 261 (2020) [C1]
DOI 10.1016/j.chemosphere.2020.128123
Citations Scopus - 15Web of Science - 10
2020 Wang X, Luo X, Wang Q, Liu Y, Naidu R, 'Predicting the combined toxicity of binary metal mixtures (Cu-Ni and Zn-Ni) to wheat.', Ecotoxicology and Environmental Safety, 205 (2020) [C1]
DOI 10.1016/j.ecoenv.2020.111334
Citations Scopus - 6Web of Science - 6
Co-authors Yanju Liu
2020 Fang C, Sobhani Z, Zhang X, Gibson CT, Tang Y, Naidu R, 'Identification and visualisation of microplastics/ nanoplastics by Raman imaging (ii): Smaller than the diffraction limit of laser?', Water Research, 183 (2020) [C1]
DOI 10.1016/j.watres.2020.116046
Citations Scopus - 73Web of Science - 48
Co-authors Cheng Fang, Zahra Sobhani
2020 Abbasi S, Moore F, Keshavarzi B, Hopke PK, Naidu R, Rahman MM, et al., 'PET-microplastics as a vector for heavy metals in a simulated plant rhizosphere zone', Science of the Total Environment, 744 (2020) [C1]
DOI 10.1016/j.scitotenv.2020.140984
Citations Scopus - 115Web of Science - 54
Co-authors Mahmud Rahman
2020 Lei YJ, Tian Y, Sobhani Z, Naidu R, Fang C, 'Synergistic degradation of PFAS in water and soil by dual-frequency ultrasonic activated persulfate', Chemical Engineering Journal, 388 (2020) [C1]
DOI 10.1016/j.cej.2020.124215
Citations Scopus - 80Web of Science - 37
Co-authors Cheng Fang, Zahra Sobhani
2020 Liu Y, Qi F, Fang C, Naidu R, Duan L, Dharmarajan R, Annamalai P, 'The effects of soil properties and co-contaminants on sorption of perfluorooctane sulfonate (PFOS) in contrasting soils', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100965
Citations Scopus - 19Web of Science - 8
Co-authors Cheng Fang, Yanju Liu
2020 Sivaram AK, Logeshwaran P, Lockington R, Naidu R, Megharaj M, 'The impact of low molecular weight organic acids from plants with C3 and C4 photosystems on the rhizoremediation of polycyclic aromatic hydrocarbons contaminated soil', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100957
Citations Scopus - 9Web of Science - 6
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2020 Al Amin M, Sobhani Z, Chadalavada S, Naidu R, Fang C, 'Smartphone-based / Fluoro-SPE for selective detection of PFAS at ppb level', Environmental Technology and Innovation, 18 (2020) [C1]
DOI 10.1016/j.eti.2020.100778
Citations Scopus - 18Web of Science - 9
Co-authors Cheng Fang, Sreenivasulu Chadalavada, Zahra Sobhani
2020 Al Amin M, Sobhani Z, Liu Y, Dharmaraja R, Chadalavada S, Naidu R, et al., 'Recent advances in the analysis of per- and polyfluoroalkyl substances (PFAS) A review', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100879
Citations Scopus - 106Web of Science - 53
Co-authors Cheng Fang, Yanju Liu, Sreenivasulu Chadalavada, Zahra Sobhani
2020 Anantha MS, Olivera S, Hu C, Jayanna BK, Reddy N, Venkatesh K, et al., 'Comparison of the photocatalytic, adsorption and electrochemical methods for the removal of cationic dyes from aqueous solutions', Environmental Technology and Innovation, 17 (2020) [C1]
DOI 10.1016/j.eti.2020.100612
Citations Scopus - 57Web of Science - 34
2020 Manna MC, Sahu A, De N, Thakur JK, Mandal A, Bhattacharjya S, et al., 'Novel bio-filtration method for the removal of heavy metals from municipal solid waste', Environmental Technology and Innovation, 17 (2020) [C1]
DOI 10.1016/j.eti.2020.100619
Citations Scopus - 10Web of Science - 5
Co-authors Mahmud Rahman
2020 Eugenio NR, Naidu R, Colombo CM, 'Global approaches to assessing, monitoring, mapping, and remedying soil pollution', ENVIRONMENTAL MONITORING AND ASSESSMENT, 192 (2020)
DOI 10.1007/s10661-020-08537-2
Citations Scopus - 3Web of Science - 4
2020 Halim MA, Rahman MM, Megharaj M, Naidu R, 'Cadmium Immobilization in the Rhizosphere and Plant Cellular Detoxification: Role of Plant-Growth-Promoting Rhizobacteria as a Sustainable Solution', Journal of Agricultural and Food Chemistry, 68 13497-13529 (2020) [C1]

Food is the major cadmium (Cd)-exposure pathway from agricultural soils to humans and other living entities and must be reduced in an effective way. A plant can select beneficial ... [more]

Food is the major cadmium (Cd)-exposure pathway from agricultural soils to humans and other living entities and must be reduced in an effective way. A plant can select beneficial microbes, like plant-growth-promoting rhizobacteria (PGPR), depending upon the nature of root exudates in the rhizosphere, for its own benefits, such as plant growth promotion as well as protection from metal toxicity. This review intends to seek out information on the rhizo-immobilization of Cd in polluted soils using the PGPR along with plant nutrient fertilizers. This review suggests that the rhizo-immobilization of Cd by a combination of PGPR and nanohybrid-based plant nutrient fertilizers would be a potential and sustainable technology for phytoavailable Cd immobilization in the rhizosphere and plant cellular detoxification, by keeping the plant nutrition flow and green dynamics of plant nutrition and boosting the plant growth and development under Cd stress.

DOI 10.1021/acs.jafc.0c04579
Citations Scopus - 28Web of Science - 9
Co-authors Mahmud Rahman, Megh Mallavarapu
2020 Usese AI, Chukwu LO, Naidu R, Islam S, Rahman MM, 'Arsenic fractionation in sediments and speciation in muscles of fish, Chrysichthys nigrodigitatus from a contaminated tropical Lagoon, Nigeria', Chemosphere, 256 (2020) [C1]
DOI 10.1016/j.chemosphere.2020.127134
Citations Scopus - 2Web of Science - 2
Co-authors Mahmud Rahman
2020 Rahman MM, Shehzad MT, Nayak AK, Sharma S, Yeasmin M, Samanta S, et al., 'Health risks from trace elements in muscles of some commonly available fish in Australia and India', Environmental Science and Pollution Research, 27 21000-21012 (2020) [C1]
DOI 10.1007/s11356-020-08600-y
Citations Scopus - 8Web of Science - 5
Co-authors Mahmud Rahman
2020 Lal MS, Megharaj M, Naidu R, Bahar MM, 'Uptake of perfluorooctane sulfonate (PFOS) by common home-grown vegetable plants and potential risks to human health', Environmental Technology and Innovation, 19 (2020) [C1]
DOI 10.1016/j.eti.2020.100863
Citations Scopus - 17Web of Science - 6
Co-authors Megh Mallavarapu, Mezbaul Bahar
2020 Duan Q, Duan L, Liu Y, Naidu R, Zhang H, Lei Y, 'A novel in-situ passive sampling technique in the application of monitoring diuron in the aquatic environment', Environmental Technology and Innovation, 20 (2020) [C1]
DOI 10.1016/j.eti.2020.101073
Citations Scopus - 6Web of Science - 4
Co-authors Yanju Liu
2020 Bekele DN, Liu Y, Donaghey M, Umeh A, Arachchige CSV, Chadalavada S, Naidu R, 'Separation and Lithological Mapping of PFAS Mixtures in the Vadose Zone at a Contaminated Site', Frontiers in Water, 2 [C1]
DOI 10.3389/frwa.2020.597810
Citations Scopus - 7Web of Science - 1
Co-authors Chamila Samarasinghe, Anthony Umeh, Dawit Bekele, Sreenivasulu Chadalavada, Yanju Liu
2020 Yan K, Dong Z, Naidu R, Liu Y, Li Y, Wijayawardena A, et al., 'Comparison of in vitro models in a mice model and investigation of the changes in Pb speciation during Pb bioavailability assessments', Journal of Hazardous Materials, 388 (2020) [C1]
DOI 10.1016/j.jhazmat.2019.121744
Citations Scopus - 15Web of Science - 11
Co-authors Yanju Liu, Ayanka Wijayawardena
2020 Hassan M, Naidu R, Du J, Liu Y, Qi F, 'Critical review of magnetic biosorbents: Their preparation, application, and regeneration for wastewater treatment', SCIENCE OF THE TOTAL ENVIRONMENT, 702 (2020) [C1]
DOI 10.1016/j.scitotenv.2019.134893
Citations Scopus - 140Web of Science - 105
Co-authors Yanju Liu
2020 Besha AT, Liu Y, Bekele DN, Dong Z, Naidu R, Gebremariam GN, 'Sustainability and environmental ethics for the application of engineered nanoparticles', ENVIRONMENTAL SCIENCE & POLICY, 103 85-98 (2020) [C1]
DOI 10.1016/j.envsci.2019.10.013
Citations Scopus - 41Web of Science - 21
Co-authors Yanju Liu, Dawit Bekele
2020 Hassan M, Liu Y, Naidu R, Parikh SJ, Du J, Qi F, Willett IR, 'Influences of feedstock sources and pyrolysis temperature on the properties of biochar and functionality as adsorbents: A meta-analysis', Science of the Total Environment, 744 (2020) [C1]
DOI 10.1016/j.scitotenv.2020.140714
Citations Scopus - 309Web of Science - 186
Co-authors Yanju Liu
2020 Zhang J, Jin J, Wang M, Naidu R, Liu Y, Man YB, et al., 'Co-pyrolysis of sewage sludge and rice husk/ bamboo sawdust for biochar with high aromaticity and low metal mobility.', Environmental Research, 191 (2020) [C1]
DOI 10.1016/j.envres.2020.110034
Citations Scopus - 89Web of Science - 49
Co-authors Yanju Liu
2020 Kulathunga MRDL, Wijayawardena MAA, Naidu R, Wimalawansa SJ, Wijeratne AW, 'Association between body mass index and estimated glomerular filtration rate in patients with chronic kidney disease of unknown aetiology in Sri Lanka', Environmental Geochemistry and Health, 42 2645-2653 (2020) [C1]
DOI 10.1007/s10653-019-00472-7
Citations Scopus - 5Web of Science - 4
Co-authors Ayanka Wijayawardena
2019 Bagherifam S, Brown TC, Fellows CM, Naidu R, 'Bioavailability of Arsenic and Antimony in Terrestrial Ecosystems: A Review', Pedosphere, 29 681-720 (2019) [C1]
DOI 10.1016/S1002-0160(19)60843-X
Citations Scopus - 48Web of Science - 39
2019 Hassan AK, Rahman MM, Chattopadhay G, Naidu R, 'Kinetic of the degradation of sulfanilic acid azochromotrop (SPADNS) by Fenton process coupled with ultrasonic irradiation or L-cysteine acceleration', Environmental Technology and Innovation, 15 (2019) [C1]
DOI 10.1016/j.eti.2019.100380
Citations Scopus - 23Web of Science - 15
Co-authors Mahmud Rahman
2019 Yan K, Dong Z, Wijayawardena MAA, Liu Y, Li Y, Naidu R, 'The source of lead determines the relationship between soil properties and lead bioaccessibility', Environmental Pollution, 246 53-59 (2019) [C1]
DOI 10.1016/j.envpol.2018.11.104
Citations Scopus - 29Web of Science - 21
Co-authors Ayanka Wijayawardena, Yanju Liu
2019 Mukkata K, Kantachote D, Wittayaweerasak B, Megharaj M, Naidu R, 'The potential of mercury resistant purple nonsulfur bacteria as effective biosorbents to remove mercury from contaminated areas', Biocatalysis and Agricultural Biotechnology, 17 93-103 (2019) [C1]
DOI 10.1016/j.bcab.2018.11.008
Citations Scopus - 21Web of Science - 14
Co-authors Megh Mallavarapu
2019 Sivaram AK, Logeshwaran P, Lockington R, Naidu R, Megharaj M, 'Phytoremediation efficacy assessment of polycyclic aromatic hydrocarbons contaminated soils using garden pea (Pisum sativum)and earthworms (Eisenia fetida)', Chemosphere, 229 227-235 (2019) [C1]
DOI 10.1016/j.chemosphere.2019.05.005
Citations Scopus - 24Web of Science - 16
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2019 Umeh AC, Panneerselvan L, Duan L, Naidu R, Semple KT, 'Bioaccumulation of benzo[a]pyrene nonextractable residues in soil by Eisenia fetida and associated background-level sublethal genotoxicity (DNA single-strand breaks)', Science of the Total Environment, 691 605-610 (2019) [C1]
DOI 10.1016/j.scitotenv.2019.07.045
Citations Scopus - 13Web of Science - 10
Co-authors Anthony Umeh, Logeshwaran Panneerselvan
2019 Biswas B, Warr LN, Hilder EF, Goswami N, Rahman MM, Churchman JG, et al., 'Biocompatible functionalisation of nanoclays for improved environmental remediation.', Chemical Society Reviews, 48 3740-3770 (2019) [C1]
DOI 10.1039/c8cs01019f
Citations Scopus - 103Web of Science - 72
Co-authors Bhaba Biswas, Mahmud Rahman
2019 Wang L, Cheng Y, Lamb D, Megharaj M, Naidu R, 'Application of Ion Selective Electrode array to simultaneously determinate multi-free ions in solution', Environmental Technology and Innovation, 15 (2019) [C1]
DOI 10.1016/j.eti.2019.100424
Citations Scopus - 10Web of Science - 8
Co-authors Megh Mallavarapu, Liang Wang, Ying Cheng
2019 Shilpi S, Lamb D, Bolan N, Seshadri B, Choppala G, Naidu R, 'Waste to watt: Anaerobic digestion of wastewater irrigated biomass for energy and fertiliser production', Journal of Environmental Management, 239 73-83 (2019) [C1]
DOI 10.1016/j.jenvman.2019.02.122
Citations Scopus - 33Web of Science - 27
Co-authors Nanthi Bolan, Girish Choppala
2019 Desalegn B, Megharaj M, Chen Z, Naidu R, 'Green synthesis of zero valent iron nanoparticle using mango peel extract and surface characterization using XPS and GC-MS', Heliyon, 5 (2019) [C1]
DOI 10.1016/j.heliyon.2019.e01750
Citations Scopus - 68Web of Science - 43
Co-authors Megh Mallavarapu
2019 Jamil S, Loganathan P, Kandasamy J, Listowski A, Khourshed C, Naidu R, Vigneswaran S, 'Removal of dissolved organic matter fractions from reverse osmosis concentrate: Comparing granular activated carbon and ion exchange resin adsorbents', Journal of Environmental Chemical Engineering, 7 (2019) [C1]
DOI 10.1016/j.jece.2019.103126
Citations Scopus - 23Web of Science - 14
2019 Goswami N, Biswas B, Naidu R, Vasilev K, 'Spatially Localized Synthesis of Metal Nanoclusters on Clay Nanotubes and Their Catalytic Performance', ACS SUSTAINABLE CHEMISTRY & ENGINEERING, 7 18350-18358 (2019) [C1]
DOI 10.1021/acssuschemeng.9b03887
Citations Scopus - 16Web of Science - 14
Co-authors Bhaba Biswas
2019 Sobhani Z, Al Amin M, Naidu R, Megharaj M, Fang C, 'Identification and visualisation of microplastics by Raman mapping', Analytica Chimica Acta, 1077 191-199 (2019) [C1]
DOI 10.1016/j.aca.2019.05.021
Citations Scopus - 137Web of Science - 89
Co-authors Zahra Sobhani, Cheng Fang, Megh Mallavarapu
2019 Subashchandrabose SR, Venkateswarlu K, Venkidusamy K, Palanisami T, Naidu R, Megharaj M, 'Bioremediation of soil long-term contaminated with PAHs by algal bacterial synergy of Chlorella sp. MM3 and Rhodococcus wratislaviensis strain 9 in slurry phase', Science of the Total Environment, 659 724-731 (2019) [C1]
DOI 10.1016/j.scitotenv.2018.12.453
Citations Scopus - 40Web of Science - 21
Co-authors Thava Palanisami, Megh Mallavarapu, Suresh Subashchandrabose
2019 Umeh AC, Duan L, Naidu R, Semple KT, 'Extremely small amounts of B[a]P residues remobilised in long-term contaminated soils: A strong case for greater focus on readily available and not total-extractable fractions in risk assessment', Journal of Hazardous Materials, 368 72-80 (2019) [C1]
DOI 10.1016/j.jhazmat.2019.01.030
Citations Scopus - 9Web of Science - 9
Co-authors Anthony Umeh
2019 España VAA, Sarkar B, Biswas B, Rusmin R, Naidu R, 'Environmental applications of thermally modified and acid activated clay minerals: Current status of the art', Environmental Technology and Innovation, 13 383-397 (2019) [C1]
DOI 10.1016/j.eti.2016.11.005
Citations Scopus - 65Web of Science - 43
Co-authors Bhaba Biswas
2019 Sanderson P, Thangavadivel K, Ranganathan S, Chadalavada S, Naidu R, Bowman M, 'Effectiveness of gravity based particle separation and soil washing for reduction of Pb in a clay loam shooting range soil', Environmental Technology and Innovation, 16 (2019) [C1]
DOI 10.1016/j.eti.2019.100480
Citations Scopus - 9Web of Science - 6
Co-authors Sreenivasulu Chadalavada
2019 Bekele DN, Du J, de Freitas LG, Mallavarapu M, Chadalavada S, Naidu R, 'Actively facilitated permeable reactive barrier for remediation of TCE from a low permeability aquifer: Field application', Journal of Hydrology, 572 592-602 (2019) [C1]
DOI 10.1016/j.jhydrol.2019.03.059
Citations Scopus - 20Web of Science - 16
Co-authors Sreenivasulu Chadalavada, Megh Mallavarapu, Dawit Bekele
2019 Wang L, Cheng Y, Lamb D, Dharmarajan R, Chadalavada S, Naidu R, 'Application of infrared spectrum for rapid classification of dominant petroleum hydrocarbon fractions for contaminated site assessment', Spectrochimica Acta Part A-Molecular And Biomolecular Spectroscopy, 207 183-188 (2019) [C1]
DOI 10.1016/j.saa.2018.09.024
Citations Scopus - 9Web of Science - 8
Co-authors Ying Cheng, Liang Wang, Sreenivasulu Chadalavada
2019 Fang C, Sobhani Z, Niu J, Naidu R, 'Removal of PFAS from aqueous solution using PbO2 from lead-acid battery', CHEMOSPHERE, 219 36-44 (2019) [C1]
DOI 10.1016/j.chemosphere.2018.11.206
Citations Scopus - 34Web of Science - 23
Co-authors Zahra Sobhani, Cheng Fang
2019 Sivaram AK, Subashchandrabose SR, Logeshwaran P, Lockington R, Naidu R, Megharaj M, 'Metabolomics reveals defensive mechanisms adapted by maize on exposure to high molecular weight polycyclic aromatic hydrocarbons.', Chemosphere, 214 771-780 (2019) [C1]
DOI 10.1016/j.chemosphere.2018.09.170
Citations Scopus - 26Web of Science - 15
Co-authors Suresh Subashchandrabose, Megh Mallavarapu, Logeshwaran Panneerselvan
2019 Sivaram AK, Logeshwaran P, Lockington R, Naidu R, Megharaj M, 'Low molecular weight organic acids enhance the high molecular weight polycyclic aromatic hydrocarbons degradation by bacteria', Chemosphere, 222 132-140 (2019) [C1]
DOI 10.1016/j.chemosphere.2019.01.110
Citations Scopus - 52Web of Science - 35
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2019 Nayak AK, Rahman MM, Naidu R, Dhal B, Swain CK, Nayak AD, et al., 'Current and emerging methodologies for estimating carbon sequestration in agricultural soils: A review', Science of the Total Environment, 665 890-912 (2019) [C1]
DOI 10.1016/j.scitotenv.2019.02.125
Citations Scopus - 76Web of Science - 48
Co-authors Mahmud Rahman
2019 Meng F, Yang X, Duan L, Naidu R, Nuruzzaman M, Semple KT, 'Influence of pH, electrical conductivity and ageing on the extractability of benzo[a]pyrene in two contrasting soils', Science of the Total Environment, 690 647-653 (2019) [C1]
DOI 10.1016/j.scitotenv.2019.06.445
Citations Scopus - 5Web of Science - 5
Co-authors Md Nuruzzaman
2019 Dong Z, Wang H, Yu YY, Li YB, Naidu R, Liu Y, 'Using 2003 2014 U.S. NHANES data to determine the associations between per- and polyfluoroalkyl substances and cholesterol: Trend and implications', Ecotoxicology and Environmental Safety, 173 461-468 (2019) [C1]
DOI 10.1016/j.ecoenv.2019.02.061
Citations Scopus - 51Web of Science - 39
Co-authors Yanju Liu
2019 Islam S, Rahman MM, Naidu R, 'Impact of water and fertilizer management on arsenic bioaccumulation and speciation in rice plants grown under greenhouse conditions.', Chemosphere, 214 606-613 (2019) [C1]
DOI 10.1016/j.chemosphere.2018.09.158
Citations Scopus - 34Web of Science - 29
Co-authors Mahmud Rahman
2019 Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Biodegradation of high-molecular weight PAHs by Rhodococcus wratislaviensis strain 9: Overexpression of amidohydrolase induced by pyrene and BaP', Science of the Total Environment, 651 813-821 (2019) [C1]
DOI 10.1016/j.scitotenv.2018.09.192
Citations Scopus - 72Web of Science - 42
Co-authors Megh Mallavarapu, Suresh Subashchandrabose
2019 Hoque MIU, Yamauchi Y, Naidu R, Holze R, Saidur R, Qu Q, et al., 'A Facile Synthesis of Hematite Nanorods from Rice Starch and Their Application to Pb(II) Ions Removal', CHEMISTRYSELECT, 4 3730-3736 (2019) [C1]
DOI 10.1002/slct.201802462
Citations Scopus - 11Web of Science - 8
Co-authors Mahmud Rahman
2019 Dong Z, Naidu R, 'Response to comment on: Dong et al. (2017) "issues raised by the reference doses for perfluorooctonate sulfonate and perfluorooctanoic acid"', ENVIRONMENT INTERNATIONAL, 126 802-803 (2019)
DOI 10.1016/j.envint.2019.01.039
Citations Scopus - 1Web of Science - 1
2019 Liu Y, Du J, Dong Z, Rahman MM, Gao Y, Yan K, Naidu R, 'Bioavailability and risk estimation of heavy metal(loid)s in chromated copper arsenate treated timber after remediation for utilisation as garden materials.', Chemosphere, 216 757-765 (2019) [C1]
DOI 10.1016/j.chemosphere.2018.10.141
Citations Scopus - 7Web of Science - 8
Co-authors Yanju Liu, Mahmud Rahman
2019 Kulathunga MRDL, Ayanka Wijayawardena MA, Naidu R, Wijeratne AW, 'Chronic kidney disease of unknown aetiology in Sri Lanka and the exposure to environmental chemicals: a review of literature', Environmental Geochemistry and Health, 41 2329-2338 (2019) [C1]
DOI 10.1007/s10653-019-00264-z
Citations Scopus - 42Web of Science - 24
Co-authors Ayanka Wijayawardena
2019 Umeh AC, Duan L, Naidu R, Esposito M, Semple KT, 'In vitro gastrointestinal mobilization and oral bioaccessibility of PAHs in contrasting soils and associated cancer risks: Focus on PAH nonextractable residues', Environment International, 133 (2019) [C1]
DOI 10.1016/j.envint.2019.105186
Citations Scopus - 19Web of Science - 15
Co-authors Anthony Umeh
2019 Simon JA, Abrams S, Bradburne T, Bryant D, Burns M, Cassidy D, et al., 'PFAS Experts Symposium: Statements on regulatory policy, chemistry and analtyics, toxicology, transport/fate, and remediation for per- and polyfluoroalkyl substances (PFAS) contamination issues', Remediation, 29 31-48 (2019) [C1]
DOI 10.1002/rem.21624
Citations Scopus - 64Web of Science - 45
2019 Bagherifam S, Brown TC, Fellows CM, Naidu R, 'Derivation methods of soils, water and sediments toxicity guidelines: A brief review with a focus on antimony', Journal of Geochemical Exploration, 205 (2019) [C1]
DOI 10.1016/j.gexplo.2019.106348
Citations Scopus - 27Web of Science - 17
2019 Perera IA, Abinandan S, Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Advances in the technologies for studying consortia of bacteria and cyanobacteria/microalgae in wastewaters', CRITICAL REVIEWS IN BIOTECHNOLOGY, 39 709-731 (2019) [C1]
DOI 10.1080/07388551.2019.1597828
Citations Scopus - 53Web of Science - 39
Co-authors Abinandan Sudharsanam, Suresh Subashchandrabose, Megh Mallavarapu
2018 Qi F, Kuppusamy S, Naidu R, Bolan NS, Ok YS, Lamb D, et al., 'Pyrogenic carbon and its role in contaminant immobilization in soils (vol 47, pg 795, 2017)', CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY, 48 535-535 (2018)
DOI 10.1080/10643389.2017.1427348
Co-authors Nanthi Bolan
2018 Cheng Y, Mallavarapu M, Naidu R, Chen Z, 'In situ fabrication of green reduced graphene-based biocompatible anode for efficient energy recycle', CHEMOSPHERE, 193 618-624 (2018) [C1]
DOI 10.1016/j.chemosphere.2017.11.057
Citations Scopus - 32Web of Science - 22
Co-authors Ying Cheng, Megh Mallavarapu
2018 Saifullah, Dahlawi S, Naeem A, Rengel Z, Naidu R, 'Biochar application for the remediation of salt-affected soils: Challenges and opportunities', Science of the Total Environment, 625 320-335 (2018) [C1]
DOI 10.1016/j.scitotenv.2017.12.257
Citations Scopus - 370Web of Science - 259
2018 Ganeshkumar V, Subashchandrabose SR, Dharmarajan R, Venkateswarlu K, Naidu R, Megharaj M, 'Use of mixed wastewaters from piggery and winery for nutrient removal and lipid production by Chlorella sp. MM3', BIORESOURCE TECHNOLOGY, 256 254-258 (2018) [C1]
DOI 10.1016/j.biortech.2018.02.025
Citations Scopus - 64Web of Science - 43
Co-authors Megh Mallavarapu, Suresh Subashchandrabose
2018 Panneerselvan L, Krishnan K, Subashchandrabose SR, Naidu R, Mallavarapu M, 'Draft Genome Sequence of Microbacterium esteraromaticum MM1, a Bacterium That Hydrolyzes the Organophosphorus Pesticide Fenamiphos, Isolated from Golf Course Soil', Microbiology Resource Announcements, 7 1-2 (2018) [C1]
DOI 10.1128/MRA.00862-18
Citations Scopus - 11Web of Science - 7
Co-authors Logeshwaran Panneerselvan, Suresh Subashchandrabose, Megh Mallavarapu
2018 Biswas JK, Banerjee A, Rai M, Naidu R, Biswas B, Vithanage M, et al., 'Potential application of selected metal resistant phosphate solubilizing bacteria isolated from the gut of earthworm (Metaphire posthuma) in plant growth promotion', Geoderma, 330 117-124 (2018) [C1]
DOI 10.1016/j.geoderma.2018.05.034
Citations Scopus - 78Web of Science - 50
Co-authors Bhaba Biswas
2018 Wijayawardena MAA, Biswas B, Qi F, Biswas JK, Khan MAI, Naidu R, 'The Fate of Chemical Pollutants with Soil Properties and Processes in the Climate Change Paradigm- a review', Soil Systems, 2 51-71 (2018) [C1]
DOI 10.3390/soilsystems2030051
Citations Scopus - 77Web of Science - 53
Co-authors Ayanka Wijayawardena, Bhaba Biswas
2018 Khan MAI, Biswas B, Smith E, Naidu R, Megharaj M, 'Toxicity assessment of fresh and weathered petroleum hydrocarbons in contaminated soil- a review.', Chemosphere, 212 755-767 (2018) [C1]
DOI 10.1016/j.chemosphere.2018.08.094
Citations Scopus - 138Web of Science - 97
Co-authors Megh Mallavarapu, Bhaba Biswas
2018 Singh G, Lakhi KS, Park D-H, Srivastava P, Naidu R, Vinu A, 'Facile One-Pot Synthesis of Activated Porous Biocarbons with a High Nitrogen Content for CO2 Capture', CHEMNANOMAT, 4 281-290 (2018) [C1]
DOI 10.1002/cnma.201700348
Citations Scopus - 41Web of Science - 36
Co-authors Ajayan Vinu, Gurwinder Singh
2018 Shilpi S, Seshadri B, Sarkar B, Bolan N, Lamb D, Naidu R, 'Comparative values of various wastewater streams as a soil nutrient source', CHEMOSPHERE, 192 272-281 (2018) [C1]
DOI 10.1016/j.chemosphere.2017.10.118
Citations Scopus - 24Web of Science - 19
Co-authors Nanthi Bolan
2018 Sivaram AK, Logeshwaran P, Lockington R, Naidu R, Megharaj M, 'Impact of plant photosystems in the remediation of benzo[a]pyrene and pyrene spiked soils', CHEMOSPHERE, 193 625-634 (2018) [C1]
DOI 10.1016/j.chemosphere.2017.11.081
Citations Scopus - 52Web of Science - 35
Co-authors Logeshwaran Panneerselvan, Megh Mallavarapu
2018 Espana VAA, Rodriguez Pinilla AR, Bardos P, Naidu R, 'Contaminated land in Colombia: A critical review of current status and future approach for the management of contaminated sites', SCIENCE OF THE TOTAL ENVIRONMENT, 618 199-209 (2018) [C1]
DOI 10.1016/j.scitotenv.2017.10.245
Citations Scopus - 37Web of Science - 23
2018 Bekele DN, Naidu R, Chadalavada S, 'Development of a modular vapor intrusion model with variably saturated and non-isothermal vadose zone', Environmental Geochemistry and Health, 40 887-902 (2018) [C1]
DOI 10.1007/s10653-017-0032-5
Citations Scopus - 12Web of Science - 8
Co-authors Sreenivasulu Chadalavada, Dawit Bekele
2018 Subashchandrabose SR, Venkateswarlu K, Krishnan K, Naidu R, Lockington R, Megharaj M, 'Rhodococcus wratislaviensis strain 9: An efficient p-nitrophenol degrader with a great potential for bioremediation', JOURNAL OF HAZARDOUS MATERIALS, 347 176-183 (2018) [C1]
DOI 10.1016/j.jhazmat.2017.12.063
Citations Scopus - 53Web of Science - 35
Co-authors Suresh Subashchandrabose, Megh Mallavarapu
2018 Basak BB, Sarkar B, Sanderson P, Naidu R, 'Waste mineral powder supplies plant available potassium: Evaluation of chemical and biological interventions', JOURNAL OF GEOCHEMICAL EXPLORATION, 186 114-120 (2018) [C1]
DOI 10.1016/j.gexplo.2017.11.023
Citations Scopus - 18Web of Science - 14
2018 Sivaram AK, Logeshwaran P, Subashchandrabose SR, Lockington R, Naidu R, Megharaj M, 'Comparison of plants with C3 and C4 carbon fixation pathways for remediation of polycyclic aromatic hydrocarbon contaminated soils', SCIENTIFIC REPORTS, 8 (2018) [C1]
DOI 10.1038/s41598-018-20317-0
Citations Scopus - 38Web of Science - 26
Co-authors Megh Mallavarapu, Suresh Subashchandrabose, Logeshwaran Panneerselvan
2018 Bahar MM, Mahbub KR, Naidu R, Megharaj M, 'As(V) removal from aqueous solution using a low-cost adsorbent coir pith ash: Equilibrium and kinetic study', Environmental Technology and Innovation, 9 198-209 (2018) [C1]
DOI 10.1016/j.eti.2017.12.005
Citations Scopus - 18Web of Science - 15
Co-authors Mezbaul Bahar, Megh Mallavarapu
2018 Besha AT, Bekele DN, Naidu R, Chadalavada S, 'Recent advances in surfactant-enhanced In-Situ Chemical Oxidation for the remediation of non-aqueous phase liquid contaminated soils and aquifers', Environmental Technology and Innovation, 9 303-322 (2018) [C1]
DOI 10.1016/j.eti.2017.08.004
Citations Scopus - 92Web of Science - 60
Co-authors Dawit Bekele, Sreenivasulu Chadalavada
2018 Biswas B, Sarkar B, Faustorilla MV, Naidu R, 'Effect of surface-tailored biocompatible organoclay on the bioavailability and mineralization of polycyclic aromatic hydrocarbons in long-term contaminated soil', Environmental Technology and Innovation, 10 152-161 (2018) [C1]
DOI 10.1016/j.eti.2018.01.013
Citations Scopus - 6Web of Science - 5
Co-authors Bhaba Biswas
2018 Wijayawardena MAA, Megharaj M, Naidu R, Stojanovski E, 'Chronic and reproductive toxicity of cadmium, zinc, and lead in binary and tertiary mixtures to the earthworm (Eisenia fetida)', JOURNAL OF SOILS AND SEDIMENTS, 18 1602-1609 (2018) [C1]
DOI 10.1007/s11368-017-1877-z
Citations Scopus - 9Web of Science - 5
Co-authors Ayanka Wijayawardena, Megh Mallavarapu, Elizabeth Stojanovski
2018 Perera I, Subashchandrabose SR, Venkateswarlu K, Naidu R, Megharaj M, 'Consortia of cyanobacteria/microalgae and bacteria in desert soils: an underexplored microbiota', APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 102 7351-7363 (2018) [C1]
DOI 10.1007/s00253-018-9192-1
Citations Scopus - 51Web of Science - 37
Co-authors Suresh Subashchandrabose, Megh Mallavarapu
2018 Khan MAI, Biswas B, Smith E, Mahmud SA, Hasan NA, Khan MAW, et al., 'Microbial diversity changes with rhizosphere and hydrocarbons in contrasting soils.', Ecotoxicology and Environmental Safety, 156 434-442 (2018) [C1]
DOI 10.1016/j.ecoenv.2018.03.006
Citations Scopus - 37Web of Science - 25
Co-authors Bhaba Biswas, Megh Mallavarapu
2018 Nookongbut P, Kantachote D, Megharaj M, Naidu R, 'Reduction in arsenic toxicity and uptake in rice (Oryza sativa L.) by As-resistant purple nonsulfur bacteria', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 25 36530-36544 (2018) [C1]
DOI 10.1007/s11356-018-3568-8
Citations Scopus - 43Web of Science - 26
Co-authors Megh Mallavarapu
2018 Thangavadivel K, Ranganathan S, Sanderson P, Chadalavada S, Naidu R, Bowman M, 'Case study of testing heavy-particle concentrator-aided remediation of lead-contaminated rifle shooting range soil', Remediation, 28 67-74 (2018) [C1]
DOI 10.1002/rem.21561
Citations Scopus - 5Web of Science - 3
Co-authors Sreenivasulu Chadalavada
2018 Plunkett SA, Wijayawardena MAA, Naidu R, Siemering GS, Tomaszewski EJ, Ginder-Vogel M, Soldat DJ, 'Use of Routine Soil Tests to Estimate Pb Bioaccessibility', Environmental Science and Technology, 52 12556-12562 (2018) [C1]
DOI 10.1021/acs.est.8b02633
Citations Scopus - 6Web of Science - 5
Co-authors Ayanka Wijayawardena
2018 Umeh AC, Duan L, Naidu R, Semple KT, 'Comparison of Single- and Sequential-Solvent Extractions of Total Extractable Benzo[a]pyrene Fractions in Contrasting Soils', Analytical Chemistry, 90 11703-11709 (2018) [C1]
DOI 10.1021/acs.analchem.8b03387
Citations Scopus - 13Web of Science - 9
Co-authors Anthony Umeh
2018 Nguyen TC, Loganathan P, Nguyen TV, Kandasamy J, Naidu R, Vigneswaran S, 'Adsorptive removal of five heavy metals from water using blast furnace slag and fly ash', Environmental Science and Pollution Research, 25 20430-20438 (2018) [C1]
DOI 10.1007/s11356-017-9610-4
Citations Scopus - 94Web of Science - 75
2018 Shahid M, Niazi NK, Dumat C, Naidu R, Khalid S, Rahman MM, Bibi I, 'A meta-analysis of the distribution, sources and health risks of arsenic-contaminated groundwater in Pakistan', Environmental Pollution, 242 307-319 (2018) [C1]
DOI 10.1016/j.envpol.2018.06.083
Citations Scopus - 166Web of Science - 135
Co-authors Mahmud Rahman
2018 Han F, Kambala VSR, Dharmarajan R, Liu Y, Naidu R, 'Photocatalytic degradation of azo dye acid orange 7 using different light sources over Fe3+-doped TiO2 nanocatalysts', Environmental Technology and Innovation, 12 27-42 (2018) [C1]
DOI 10.1016/j.eti.2018.07.004
Citations Scopus - 41Web of Science - 34
Co-authors Yanju Liu
2018 Yan K, Naidu R, Liu Y, Wijayawardena A, Duan L, Dong Z, 'A Pooled Data Analysis to Determine the Relationship between Selected Metals and Arsenic Bioavailability in Soil', International Journal of Environmental Research and Public Health, 15 (2018) [C1]
DOI 10.3390/ijerph15050888
Citations Scopus - 8Web of Science - 6
Co-authors Yanju Liu, Ayanka Wijayawardena
2018 Rashid MH, Rahman MM, Correll R, Naidu R, 'Arsenic and Other Elemental Concentrations in Mushrooms from Bangladesh: Health Risks.', International Journal of Environmental Research and Public Health, 15 (2018) [C1]
DOI 10.3390/ijerph15050919
Citations Scopus - 25Web of Science - 20
Co-authors Mahmud Rahman
2018 Qi F, Lamb D, Naidu R, Bolan NS, Yan Y, Ok YS, et al., 'Cadmium solubility and bioavailability in soils amended with acidic and neutral biochar', SCIENCE OF THE TOTAL ENVIRONMENT, 610 1457-1466 (2018) [C1]
DOI 10.1016/j.scitotenv.2017.08.228
Citations Scopus - 78Web of Science - 61
Co-authors Nanthi Bolan, Girish Choppala, Mahmud Rahman
2018 Yu L, Duan L, Naidu R, Semple KT, 'Abiotic factors controlling bioavailability and bioaccessibility of polycyclic aromatic hydrocarbons in soil: Putting together a bigger picture', SCIENCE OF THE TOTAL ENVIRONMENT, 613 1140-1153 (2018) [C1]
DOI 10.1016/j.scitotenv.2017.09.025
Citations Scopus - 68Web of Science - 53
2018 Fang C, Sobhani Z, Megharaj M, Naidu R, 'Electrochemical Proof of Fluorophilic Interaction Among Fluoro-Carbon Chains', Electroanalysis, 30 2349-2355 (2018) [C1]
DOI 10.1002/elan.201800190
Citations Scopus - 8Web of Science - 3
Co-authors Megh Mallavarapu, Cheng Fang, Zahra Sobhani
2018 Umeh AC, Duan L, Naidu R, Semple KT, 'Enhanced Recovery of Nonextractable Benzo[a]pyrene Residues in Contrasting Soils Using Exhaustive Methanolic and Nonmethanolic Alkaline Treatments', Analytical Chemistry, 90 13104-13111 (2018) [C1]
DOI 10.1021/acs.analchem.8b04440
Citations Scopus - 8Web of Science - 6
Co-authors Anthony Umeh
2018 Umeh AC, Duan L, Naidu R, Semple KT, 'Time-Dependent Remobilisation of Non-Extractable Benzo[a]pyrene Residues in Contrasting Soils: Effects of Aging, Spiked Concentration, and Soil Properties.', ENVIRONMENTAL SCIENCE & TECHNOLOGY, 52 12295-12305 (2018) [C1]
DOI 10.1021/acs.est.8b03008
Citations Scopus - 25Web of Science - 23
Co-authors Anthony Umeh
2018 Kader M, Lamb DT, Wang L, Megharaj M, Naidu R, 'Copper interactions on arsenic bioavailability and phytotoxicity in soil', Ecotoxicology and Environmental Safety, 148 738-746 (2018) [C1]
DOI 10.1016/j.ecoenv.2017.11.025
Citations Scopus - 15Web of Science - 15
Co-authors Megh Mallavarapu, Liang Wang
2018 Selvakumar R, Ramadoss G, Mridula PM, Rajendran K, Thavamani P, Ravi N, Megharaj M, 'Challenges and complexities in remediation of uranium contaminated soils: A review', Journal of Environmental Radioactivity, 192 592-603 (2018) [C1]
DOI 10.1016/j.jenvrad.2018.02.018
Citations Scopus - 89Web of Science - 61
Co-authors Thava Palanisami, Megh Mallavarapu
2018 Gao YC, Guo SH, Wang JN, Zhang W, Chen GH, Wang H, et al., 'Novel Bacillus cereus strain from electrokinetically remediated saline soil towards the remediation of crude oil', Environmental Science and Pollution Research, 25 26351-26360 (2018) [C1]
DOI 10.1007/s11356-018-2495-z
Citations Scopus - 4Web of Science - 3
Co-authors Yanju Liu
2018 Rocco C, Seshadri B, Adamo P, Bolan NS, Mbene K, Naidu R, 'Impact of waste-derived organic and inorganic amendments on the mobility and bioavailability of arsenic and cadmium in alkaline and acid soils', Environmental Science and Pollution Research, 25 25896-25905 (2018) [C1]
DOI 10.1007/s11356-018-2655-1
Citations Scopus - 42Web of Science - 35
Co-authors Nanthi Bolan
2018 Li Y, Li W, Xiao Q, Song S, Liu Y, Naidu R, 'Acid mine drainage remediation strategies: A review on migration and source controls', Minerals and Metallurgical Processing, 35 148-158 (2018) [C1]
DOI 10.19150/mmp.8464
Citations Scopus - 23Web of Science - 21
Co-authors Yanju Liu
2018 Nuruzzaman M, Liu Y, Rahman MM, Naidu R, Dharmarajan R, Shon HK, Woo YC, 'Core-Shell Interface-Oriented Synthesis of Bowl-Structured Hollow Silica Nanospheres Using Self-Assembled ABC Triblock Copolymeric Micelles.', Langmuir : the ACS journal of surfaces and colloids, 34 13584-13596 (2018) [C1]
DOI 10.1021/acs.langmuir.8b00792
Citations Scopus - 9Web of Science - 10
Co-authors Md Nuruzzaman, Yanju Liu, Mahmud Rahman
2018 Sanderson P, Qi F, Seshadri B, Wijayawardena A, Naidu R, 'Contamination, Fate and Management of Metals in Shooting Range Soils - a Review', Current Pollution Reports, 4 175-187 (2018) [C1]
DOI 10.1007/s40726-018-0089-5
Citations Scopus - 32Web of Science - 20
Co-authors Ayanka Wijayawardena
2018 Samarasinghe SVAC, Krishnan K, Naidu R, Megharaj M, Miller K, Fraser B, Aitken RJ, 'Parabens generate reactive oxygen species in human spermatozoa', ANDROLOGY, 6 532-541 (2018) [C1]
DOI 10.1111/andr.12499
Citations Scopus - 51Web of Science - 32
Co-authors Megh Mallavarapu, John Aitken, Chamila Samarasinghe
2018 Kumar M, Ramanathan AL, Mukherjee A, Verma S, Rahman MM, Naidu R, 'Hydrogeo-morphological influences for arsenic release and fate in the central Gangetic Basin, India', Environmental Technology and Innovation, 12 243-260 (2018) [C1]
DOI 10.1016/j.eti.2018.09.004
Citations Scopus - 21Web of Science - 17
Co-authors Mahmud Rahman
2018 Shakoor MB, Bibi I, Niazi NK, Shahid M, Nawaz MF, Farooqi A, et al., 'The evaluation of arsenic contamination potential, speciation and hydrogeochemical behaviour in aquifers of Punjab, Pakistan', Chemosphere, 199 737-746 (2018) [C1]
DOI 10.1016/j.chemosphere.2018.02.002
Citations Scopus - 115Web of Science - 96
Co-authors Mahmud Rahman
2018 Hussain I, Aleti G, Naidu R, Puschenreiter M, Mahmood Q, Rahman MM, et al., 'Microbe and plant assisted-remediation of organic xenobiotics and its enhancement by genetically modified organisms and recombinant technology: A review', Science of the Total Environment, 628-629 1582-1599 (2018) [C1]
DOI 10.1016/j.scitotenv.2018.02.037
Citations Scopus - 105Web of Science - 61
Co-authors Mahmud Rahman
2018 Wang Z, Tan X, Lu G, Liu Y, Naidu R, He W, 'Soil properties influence kinetics of soil acid phosphatase in response to arsenic toxicity', ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 147 266-274 (2018) [C1]
DOI 10.1016/j.ecoenv.2017.08.050
Citations Scopus - 36Web of Science - 25
Co-authors Yanju Liu
2018 Logeshwaran P, Megharaj M, Chadalavada S, Bowman M, Naidu R, 'Petroleum hydrocarbons (PH) in groundwater aquifers: An overview of environmental fate, toxicity, microbial degradation and risk-based remediation approaches', Environmental Technology & Innovation, 10 175-193 (2018) [C1]
DOI 10.1016/j.eti.2018.02.001
Citations Scopus - 140Web of Science - 81
Co-authors Sreenivasulu Chadalavada, Megh Mallavarapu, Logeshwaran Panneerselvan
2018 Kong L, Tian Y, Li N, Liu Y, Zhang J, Zhang J, Zuo W, 'Highly-effective phosphate removal from aqueous solutions by calcined nano-porous palygorskite matrix with embedded lanthanum hydroxide', APPLIED CLAY SCIENCE, 162 507-517 (2018) [C1]
DOI 10.1016/j.clay.2018.07.005
Citations Web of Science - 74
2018 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Bioavailability of weathered hydrocarbons in engine oil-contaminated soil: Impact of bioaugmentation mediated by Pseudomonas spp. on bioremediation', Science of the Total Environment, 636 968-974 (2018) [C1]

Heavier fraction hydrocarbons (C15-C36) formed in soil after biotic and abiotic weatherings of engine oil are the continuing constraints in the bioremediation strategy, and their ... [more]

Heavier fraction hydrocarbons (C15-C36) formed in soil after biotic and abiotic weatherings of engine oil are the continuing constraints in the bioremediation strategy, and their bioavailability remains a poorly quantified regulatory factor. In a microcosm study, we used two strains of Pseudomonas, P. putida TPHK-1 and P. aeruginosa TPHK-4, in strategies of bioremediation, viz., natural attenuation, biostimulation and bioaugmentation, for removal of weathered total petroleum hydrocarbons (TPHs) in soil contaminated long-term with high concentrations of engine oil (39,000¿41,000 mg TPHs kg-1 soil). Both the bacterial strains exhibited a great potential in remediating weathered hydrocarbons of engine oil. Addition of inorganic fertilizers (NPK), at recommended levels for bioremediation, resulted in significant inhibition in biostimulation/enhanced natural attenuation as well as bioaugmentation. The data on dehydrogenase activity clearly confirmed those of bioremediation strategies used, indicating that this enzyme assay could serve as an indicator of bioremediation potential of oil-contaminated soil. Extraction of TPHs from engine oil-contaminated soil with hydroxypropyl-ß-cyclodextrin (HPCD), but not 1-butanol, was found reliable in predicting the bioavailability of weathered hydrocarbons. Also, 454 pyrosequencing data were in accordance with those of bioremediation strategies used in the present microcosm study, suggesting the possible use of pyrosequencing in designing approaches for bioremediation.

DOI 10.1016/j.scitotenv.2018.04.379
Citations Scopus - 103Web of Science - 81
Co-authors Megh Mallavarapu, Kavitha Ramadass
2018 Lu G, Tian H, Liu Y, Naidu R, Wang Z, He W, 'Using Qmsax* to evaluate the reasonable As(V) adsorption on soils with different pH', Ecotoxicology and Environmental Safety, 160 308-315 (2018) [C1]
DOI 10.1016/j.ecoenv.2018.05.043
Citations Scopus - 7Web of Science - 6
Co-authors Yanju Liu
2018 Desalegn B, Megharaj M, Chen Z, Naidu R, 'Green mango peel-nanozerovalent iron activated persulfate oxidation of petroleum hydrocarbons in oil sludge contaminated soil', Environmental Technology and Innovation, 11 142-152 (2018) [C1]
DOI 10.1016/j.eti.2018.05.007
Citations Scopus - 36Web of Science - 25
Co-authors Megh Mallavarapu
2018 Fang C, Zhang X, Dong Z, Wang L, Megharaj M, Naidu R, 'Smartphone app-based/portable sensor for the detection of fluoro-surfactant PFOA.', Chemosphere, 191 381-388 (2018) [C1]
DOI 10.1016/j.chemosphere.2017.10.057
Citations Scopus - 54Web of Science - 37
Co-authors Megh Mallavarapu, Liang Wang, Cheng Fang
2017 Qi F, Yan Y, Lamb D, Naidu R, Bolan NS, Liu Y, et al., 'Thermal stability of biochar and its effects on cadmium sorption capacity', BIORESOURCE TECHNOLOGY, 246 48-56 (2017) [C1]
DOI 10.1016/j.biortech.2017.07.033
Citations Scopus - 68Web of Science - 54
Co-authors Yanju Liu, Scott Donne, Nanthi Bolan
2017 Chowdhury S, Thangarajan R, Bolan N, O'Reilly-Wapstra J, Kunhikrishnan A, Naidu R, 'Nitrification potential in the rhizosphere of Australian native vegetation', SOIL RESEARCH, 55 58-69 (2017) [C1]
DOI 10.1071/SR16116
Citations Scopus - 11Web of Science - 10
Co-authors Nanthi Bolan
2017 Kuppusamy S, Thavamani P, Singh S, Naidu R, Megharaj M, 'Polycyclic aromatic hydrocarbons (PAHs) degradation potential, surfactant production, metal resistance and enzymatic activity of two novel cellulose-degrading bacteria isolated from koala faeces', ENVIRONMENTAL EARTH SCIENCES, 76 (2017) [C1]
DOI 10.1007/s12665-016-6337-3
Citations Scopus - 16Web of Science - 15
Co-authors Megh Mallavarapu, Thava Palanisami
2017 Subashchandrabose SR, Wang L, Venkateswarlu K, Naidu R, Megharaj M, 'Interactive effects of PAHs and heavy metal mixtures on oxidative stress in Chlorella sp MM3 as determined by artificial neural network and genetic algorithm', ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS, 21 203-212 (2017) [C1]
DOI 10.1016/j.algal.2016.11.018
Citations Scopus - 28Web of Science - 20
Co-authors Suresh Subashchandrabose, Liang Wang, Megh Mallavarapu
2017 Mayilswami S, Krishnan K, Naidu R, Megharaj M, 'Transcriptome analysis of Eisenia fetida chronically exposed to benzo(a)pyrene', Environmental Technology & Innovation, 7 54-62 (2017) [C1]
DOI 10.1016/j.eti.2016.12.002
Citations Scopus - 5Web of Science - 2
Co-authors Megh Mallavarapu
2017 Thavamani P, Samkumar RA, Satheesh V, Subashchandrabose SR, Ramadass K, Naidu R, et al., 'Microbes from mined sites: Harnessing their potential for reclamation of derelict mine sites', Environmental Pollution, 230 495-505 (2017) [C1]
DOI 10.1016/j.envpol.2017.06.056
Citations Scopus - 87Web of Science - 64
Co-authors Kavitha Ramadass, Suresh Subashchandrabose, Thava Palanisami, Megh Mallavarapu
2017 Qi F, Kuppusamy S, Naidu R, Bolan NS, Ok YS, Lamb D, et al., 'Pyrogenic carbon and its role in contaminant immobilization in soils', CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY, 47 795-876 (2017) [C1]
DOI 10.1080/10643389.2017.1328918
Citations Scopus - 71Web of Science - 64
Co-authors Nanthi Bolan
2017 Karunanithi R, Sik Ok Y, Dharmarajan R, Ahmad M, Seshadri B, Bolan N, Naidu R, 'Sorption, kinetics and thermodynamics of phosphate sorption onto soybean stover derived biochar', Environmental Technology and Innovation, 8 113-125 (2017) [C1]
DOI 10.1016/j.eti.2017.06.002
Citations Scopus - 49Web of Science - 34
Co-authors Nanthi Bolan
2017 Megharaj M, Naidu R, 'Soil and brownfield bioremediation', MICROBIAL BIOTECHNOLOGY, 10 1244-1249 (2017) [C1]
DOI 10.1111/1751-7915.12840
Citations Scopus - 81Web of Science - 50
Co-authors Megh Mallavarapu
2017 Du J, Chadalavada S, Naidu R, 'Synthesis of porous bentonite organoclay granule and its adsorption of tributyltin', Applied Clay Science, 148 131-137 (2017) [C1]
DOI 10.1016/j.clay.2017.07.033
Citations Scopus - 10Web of Science - 9
Co-authors Sreenivasulu Chadalavada
2017 Mahbub KR, Bahar MM, Labbate M, Krishnan K, Andrews S, Naidu R, Megharaj M, 'Bioremediation of mercury: not properly exploited in contaminated soils!', APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 101 963-976 (2017) [C1]
DOI 10.1007/s00253-016-8079-2
Citations Scopus - 56Web of Science - 35
Co-authors Megh Mallavarapu, Mezbaul Bahar
2017 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Ecotoxicity of measured concentrations of soil-applied diesel: Effects on earthworm survival, dehydrogenase, urease and nitrification activities', Applied Soil Ecology, 119 1-7 (2017) [C1]

Diesel is an important petroleum product, and a common pollutant in soil caused by leaks and accidental spills. Studies dealing with the ecotoxicity of diesel towards earthworms a... [more]

Diesel is an important petroleum product, and a common pollutant in soil caused by leaks and accidental spills. Studies dealing with the ecotoxicity of diesel towards earthworms always relied on growth inhibition endpoint (EC50) values that were determined based on the spiked concentrations (nominal), ignoring the substantial portion of hydrocarbons volatilized from soil. In the present study we used, for the first time, the measured concentrations of total petroleum hydrocarbons (TPHs) from soil-applied diesel to assess earthworm (Eisenia fetida) survival, and the activities of dehydrogenase, urease and nitrification as indicators of soil health. The mortality endpoint (LC50) value for initially measured concentrations after exposure of earthworms to diesel for 28¿days was 916¿±¿10¿mg TPHs kg-1 soil which was equivalent to the nominal (initially added) concentration of 1426¿±¿19¿mg TPHs kg-1 soil. Morphological abnormalities such as clitella swelling and curling were noticed when the measured concentrations of diesel were more than 971¿mg¿kg-1 soil. Significant increases in activities of soil dehydrogenase (38¿58%) as well as urease were observed in the diesel-applied soil. Presence of earthworms further enhanced the activities of these soil enzymes. Nitrification was sensitive to application of diesel to soil, and it was inhibited in a dose-related manner even in the presence of earthworms. The differential response of the toxicity criteria to diesel-contaminated soil observed in the present study clearly warrants more studies involving several soil health parameters to arrive at a generalization of ecotoxicity of an environmental pollutant.

DOI 10.1016/j.apsoil.2017.05.017
Citations Scopus - 23Web of Science - 19
Co-authors Kavitha Ramadass, Megh Mallavarapu
2017 Cheng Y, Wang L, Faustorilla V, Mallavarapu M, Naidu R, Chen Z, 'Integrated electrochemical treatment systems for facilitating the bioremediation of oil spill contaminated soil', Chemosphere, 175 294-299 (2017) [C1]
DOI 10.1016/j.chemosphere.2017.02.079
Citations Scopus - 27Web of Science - 19
Co-authors Megh Mallavarapu, Liang Wang, Ying Cheng
2017 Biswas B, Sarkar B, Naidu R, 'Bacterial mineralization of phenanthrene on thermally activated palygorskite: A C-14 radiotracer study', SCIENCE OF THE TOTAL ENVIRONMENT, 579 709-717 (2017) [C1]
DOI 10.1016/j.scitotenv.2016.11.037
Citations Scopus - 13Web of Science - 10
Co-authors Bhaba Biswas
2017 Islam S, Rahman MM, Islam MR, Naidu R, 'Effect of irrigation and genotypes towards reduction in arsenic load in rice', Science of the Total Environment, 609 311-318 (2017) [C1]

Arsenic (As) bioaccumulation in rice grains has been identified as a major problem in Bangladesh and many other parts of the world. Suitable rice genotypes along with proper water... [more]

Arsenic (As) bioaccumulation in rice grains has been identified as a major problem in Bangladesh and many other parts of the world. Suitable rice genotypes along with proper water management practice regulating As levels in rice plants must be chosen and implemented. A field study was conducted to investigate the effect of continuous flooding (CF) and alternate wetting and drying (AWD) irrigation on the bioaccumulation of As in ten rice cultivars at three locations having different levels of soil As and irrigation water As. Results showed that As concentration in different parts of rice plants varied significantly (P¿<¿0.0001) with rice genotypes and irrigation practices in the three study locations. Lower levels of As in rice were found in AWD irrigation practice compared to CF irrigation practice. Higher grain As bioaccumulation was detected in plants in areas of high soil As in combination with CF irrigation practice. Our data show that use of AWD irrigation practice with suitable genotypes led to 17 to 35% reduction in grain As level, as well as 7 to 38% increase in grain yield. Overall, this study advances our understanding that, for moderate to high levels of As contamination, the Binadhan-5, Binadhan-6, Binadhan-8, Binadhan-10 and BRRI dhan47 varieties were quite promising to mitigate As induced human health risk.

DOI 10.1016/j.scitotenv.2017.07.111
Citations Scopus - 35Web of Science - 25
Co-authors Mahmud Rahman
2017 Mahbub KR, Krishnan K, Andrews S, Venter H, Naidu R, Mallavarapu M, 'Bio-augmentation and nutrient amendment decrease concentration of mercury in contaminated soil', Science of the Total Environment, 576 303-309 (2017) [C1]
DOI 10.1016/j.scitotenv.2016.10.083
Citations Scopus - 39Web of Science - 32
Co-authors Megh Mallavarapu
2017 Naidu R, Sanderson P, 'Novel risk-based approaches to derelict mine management', Journal of Health, Safety and Environment, 33 (2017)
2017 Biswas B, Chakraborty A, Sarkar B, Naidu R, 'Structural changes in smectite due to interaction with a biosurfactant-producing bacterium Pseudoxanthomonas kaohsiungensis', APPLIED CLAY SCIENCE, 136 51-57 (2017) [C1]
DOI 10.1016/j.clay.2016.11.008
Citations Scopus - 25Web of Science - 16
Co-authors Bhaba Biswas
2017 Mahbub KR, Bahar MM, Labbate M, Krishnan K, Andrews S, Naidu R, Megharaj M, 'Bioremediation of mercury: not properly exploited in contaminated soils!', APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 101 963-976 (2017) [C1]
DOI 10.1007/s00253-016-8079-2
Citations Scopus - 50Web of Science - 35
Co-authors Megh Mallavarapu, Mezbaul Bahar
2017 Biswas B, Sarkar B, Rusmin R, Naidu R, 'Mild acid and alkali treated clay minerals enhance bioremediation of polycyclic aromatic hydrocarbons in long-term contaminated soil: A C-14-tracer study', ENVIRONMENTAL POLLUTION, 223 255-265 (2017) [C1]
DOI 10.1016/j.envpol.2017.01.022
Citations Scopus - 28Web of Science - 22
Co-authors Bhaba Biswas
2017 Wang L, Cheng Y, Lamb D, Lesniewski P, Chen Z, Mallavarapu M, Naidu R, 'Novel recalibration methodologies for ion-selective electrode arrays in the multi-ion interference scenario', Journal of Chemometrics, 31 (2017) [C1]
DOI 10.1002/cem.2870
Citations Scopus - 3Web of Science - 3
Co-authors Liang Wang, Ying Cheng, Megh Mallavarapu
2017 Faustorilla MV, Chen Z, Dharmarajan R, Naidu R, 'Determination of Total Petroleum Hydrocarbons in Australian Groundwater Through the Improvised Gas Chromatography-Flame Ionization Detection Technique', JOURNAL OF CHROMATOGRAPHIC SCIENCE, 55 775-783 (2017) [C1]
DOI 10.1093/chromsci/bmx038
Citations Scopus - 15Web of Science - 8
2017 Qi F, Dong Z, Lamb D, Naidu R, Bolan NS, Ok YS, et al., 'Effects of acidic and neutral biochars on properties and cadmium retention of soils', CHEMOSPHERE, 180 564-573 (2017) [C1]
DOI 10.1016/j.chemosphere.2017.04.014
Citations Scopus - 60Web of Science - 51
Co-authors Nanthi Bolan
2017 Yan K, Dong Z, Wijayawardena MAA, Liu Y, Naidu R, Semple K, 'Measurement of soil lead bioavailability and influence of soil types and properties: A review', CHEMOSPHERE, 184 27-42 (2017) [C1]
DOI 10.1016/j.chemosphere.2017.05.143
Citations Scopus - 56Web of Science - 40
Co-authors Yanju Liu, Ayanka Wijayawardena
2017 Qi F, Naidu R, Bolan NS, Dong Z, Yan Y, Lamb D, et al., 'Pyrogenic carbon in Australian soils', SCIENCE OF THE TOTAL ENVIRONMENT, 586 849-857 (2017) [C1]
DOI 10.1016/j.scitotenv.2017.02.064
Citations Scopus - 14Web of Science - 11
Co-authors Girish Choppala, Nanthi Bolan
2017 Dong Z, Bahar MM, Jit J, Kennedy B, Priestly B, Ng J, et al., 'Issues raised by the reference doses for perfluorooctane sulfonate and perfluorooctanoic acid', ENVIRONMENT INTERNATIONAL, 105 86-94 (2017) [C1]
DOI 10.1016/j.envint.2017.05.006
Citations Scopus - 39Web of Science - 33
Co-authors Yanju Liu, Mezbaul Bahar
2017 Kuppusamy S, Venkateswarlu K, Thavamani P, Lee YB, Naidu R, Megharaj M, 'Quercus robur acorn peel as a novel coagulating adsorbent for cationic dye removal from aquatic ecosystems', ECOLOGICAL ENGINEERING, 101 3-8 (2017) [C1]
DOI 10.1016/j.ecoleng.2017.01.014
Citations Scopus - 58Web of Science - 48
Co-authors Thava Palanisami, Megh Mallavarapu
2017 Liu Y, Bello O, Rahman MM, Dong Z, Islam S, Naidu R, 'Investigating the relationship between lead speciation and bioaccessibility of mining impacted soils and dusts', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 24 17056-17067 (2017) [C1]
DOI 10.1007/s11356-017-9250-8
Citations Scopus - 12Web of Science - 9
Co-authors Yanju Liu, Mahmud Rahman
2017 Mahbub K, Krishnan K, Naidu R, Megharaj M, 'Development of a whole cell biosensor for the detection of inorganic mercury', Environmental Technology and Innovation, 8 64-70 (2017) [C1]
DOI 10.1016/j.eti.2017.04.003
Citations Scopus - 28Web of Science - 20
Co-authors Megh Mallavarapu
2017 Fang C, Megharaj M, Naidu R, 'Electrochemical Detection of Thioether-Based Fluorosurfactants in Aqueous Film-Forming Foam (AFFF)', Electroanalysis, 29 1095-1102 (2017) [C1]
DOI 10.1002/elan.201600724
Citations Scopus - 4Web of Science - 4
Co-authors Megh Mallavarapu, Cheng Fang
2017 Fang C, Megharaj M, Naidu R, 'Electrochemical Studies on Self-Assembled Monolayer (SAM) Upon Exposure to Anionic Surfactants: PFOA, PFOS, SDS and SDBS', Electroanalysis, 29 2155-2160 (2017) [C1]
DOI 10.1002/elan.201700108
Citations Scopus - 7Web of Science - 4
Co-authors Cheng Fang, Megh Mallavarapu
2017 Kalaruban M, Loganathan P, Kandasamy J, Naidu R, Vigneswaran S, 'Enhanced removal of nitrate in an integrated electrochemical-adsorption system', Separation and Purification Technology, 189 260-266 (2017) [C1]

The electrochemical (EC) method of removing pollutants in water is a widely used process in water and wastewater treatment. An EC-adsorption integrated system was investigated to ... [more]

The electrochemical (EC) method of removing pollutants in water is a widely used process in water and wastewater treatment. An EC-adsorption integrated system was investigated to test whether the simultaneous removal of nitrate by the two processes would be better than removal utilising the individual EC and adsorption methods. In the integrated system, an adsorbent (ion exchange resin - Dowex 21k XLT) was placed inside a stainless steel box that served as an anode with a Cu plate as cathode. In an experiment using 2 L nitrate solution containing 20 mg N/L and 2 g adsorbent the rate of nitrate removal in the integrated system was initially fast with 35% removed in 30 min, though slowing down later. The rate of removal increased with increasing current, voltage and pH up to 7 but decreased as the distance between the electrodes also increased. The optimum nitrate removal of 67% was obtained at pH 7, 1 A, and 31 V for a distance of 1 cm between the electrodes after 180 min. The amount of nitrate removed fell when sulphate was present in the integrated system due to sulphate competing with nitrate for adsorption. Concentration of ammonium produced by nitrate reduction in the EC system was reduced in the presence of adsorbent. Nitrate removal in the integrated system is approximately equal to the sum of the removals in the two individual processes.

DOI 10.1016/j.seppur.2017.08.010
Citations Scopus - 40Web of Science - 37
2017 Sanderson P, Naidu R, Bolan N, 'Application of a biodegradable chelate to enhance subsequent chemical stabilisation of Pb in shooting range soils', JOURNAL OF SOILS AND SEDIMENTS, 17 1696-1705 (2017) [C1]
DOI 10.1007/s11368-016-1608-x
Citations Scopus - 8Web of Science - 7
Co-authors Nanthi Bolan
2017 Fang C, Megharaj M, Naidu R, 'Electrochemical switch on-off response of a self-assembled monolayer (SAM) upon exposure to perfluorooctanoic acid (PFOA)', JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 785 249-254 (2017) [C1]
DOI 10.1016/j.jelechem.2016.12.040
Citations Scopus - 9Web of Science - 8
Co-authors Megh Mallavarapu, Cheng Fang
2017 Islam S, Rahman MM, Rahman MA, Naidu R, 'Inorganic arsenic in rice and rice-based diets: Health risk assessment', Food Control, 82 196-202 (2017) [C1]

Total and inorganic arsenic (As) content in rice and rice-based diets (n = 59) obtained from supermarkets in South Australia were studied to investigate the contamination levels a... [more]

Total and inorganic arsenic (As) content in rice and rice-based diets (n = 59) obtained from supermarkets in South Australia were studied to investigate the contamination levels and whether consumption of these products pose potential health risks to young children and adults. Results show that of the 59 rice-based products, 31 (53%) exceeded the EU recommended value (100 µg/kg) of As for young children and 13 (22%) samples had higher than maximum level of 200 µg/kg recommended for adults. Arsenic content varies as rice crackers > baby rice > rice cakes > puffed rice > other rice-based snacks > ready-to-eat rice. Of the 6 categories of rice-based products, except ready-to-eat rice, all others exceeded the EU recommended value for young children. Even manufacture recommended servings deliver significant amounts (0.56¿6.87 µg) of inorganic As. These amounts are within the range of BMDL01 values indicated by the European Food Safety Authority (EFSA), which means the risk cannot be avoided for young children and adults considering the levels of total and inorganic As in rice-based products.

DOI 10.1016/j.foodcont.2017.06.030
Citations Scopus - 64Web of Science - 40
Co-authors Mahmud Rahman
2017 Singh G, Lakhi KS, Kim IY, Kim S, Srivastava P, Naidu R, Vinu A, 'Highly Efficient Method for the Synthesis of Activated Mesoporous Biocarbons with Extremely High Surface Area for High-Pressure CO2 Adsorption.', ACS Applied Materials & Interfaces, 9 29782-29793 (2017) [C1]
DOI 10.1021/acsami.7b08797
Citations Scopus - 123Web of Science - 91
Co-authors Gurwinder Singh, Ajayan Vinu
2017 Khandaker Rayhan Mahbub, Krishnan K, Naidu R, Mallavarapu M, 'Mercury remediation potential of a mercury resistant strain Sphingopyxis sp. SE2 isolated from contaminated soil', Journal of Environmental Sciences, 51 128-137 (2017) [C1]
DOI 10.1016/j.jes.2016.06.032
Citations Scopus - 35Web of Science - 25
Co-authors Megh Mallavarapu
2017 Khandaker Rayhan Mahbub, Krishnan K, Naidu R, Megharaj M, 'Mercury toxicity to Eisenia fetida in three different soils', Environmental Science and Pollution Research, 24 1261-1269 (2017) [C1]
DOI 10.1007/s11356-016-7869-5
Citations Scopus - 18Web of Science - 14
Co-authors Megh Mallavarapu
2017 Wijayawardena AMA, Megharaj M, Naidu R, 'Bioaccumulation and toxicity of lead, influenced by edaphic factors: using earthworms to study the effect of Pb on ecological health', Journal of Soils and Sediments, 17 1064-1072 (2017) [C1]
DOI 10.1007/s11368-016-1605-0
Citations Scopus - 21Web of Science - 15
Co-authors Ayanka Wijayawardena, Megh Mallavarapu
2017 Singh G, Kim IY, Lakhi KS, Srivastava P, Naidu R, Vinu A, 'Single step synthesis of activated bio-carbons with a high surface area and their excellent CO2 adsorption capacity', CARBON, 116 448-455 (2017) [C1]
DOI 10.1016/j.carbon.2017.02.015
Citations Scopus - 248Web of Science - 211
Co-authors Gurwinder Singh, Ajayan Vinu
2017 Bolan S, Kunhikrishnan A, Chowdhury S, Seshadri B, Naidu R, Ok YS, 'Comparative analysis of speciation and bioaccessibility of arsenic in rice grains and complementary medicines', CHEMOSPHERE, 182 433-440 (2017) [C1]
DOI 10.1016/j.chemosphere.2017.04.126
Citations Scopus - 19Web of Science - 15
2017 Islam S, Rahman MM, Islam MR, Naidu R, 'Geographical variation and age-related dietary exposure to arsenic in rice from Bangladesh', Science of the Total Environment, 601-602 122-131 (2017) [C1]

An extensive number (965) of rice samples collected by household survey from 73 upazilas (i.e. sub-districts) in Bangladesh was analyzed to determine regional variation, distribut... [more]

An extensive number (965) of rice samples collected by household survey from 73 upazilas (i.e. sub-districts) in Bangladesh was analyzed to determine regional variation, distribution and associated health risks from arsenic (As). No previous study had conducted a study examining such a large number of rice samples. The mean and median concentrations of total As were 126¿µg/kg and 107¿µg/kg, respectively, ranging from between 3 and 680¿µg/kg. Importantly, total As levels of aromatic rice were significantly lower (average 58¿µg/kg) than non-aromatic rice (average 150¿µg/kg) and also varied with rice grain size. The variation in As content was dominated by the location (47% among the upazilas, 71% among districts) and rice variety (14%). Inorganic As content in rice grain ranged between 11 and 502¿µg/kg (n¿=¿162) with the highest fraction being 98.6%. The daily intake of inorganic As from rice ranged between 0.38 and 1.92¿µg/kg BW in different districts. The incremental lifetime cancer risk (ILCR) for individuals due to the consumption of rice varied between 0.57¿×¿10-¿3 to 2.88¿×¿10-¿3 in different districts, and 0.54¿×¿10-¿3 to 2.12¿×¿10-¿3 in different varieties, higher than the US EPA threshold. The 2¿10 age group experiences higher carcinogenic risks than others and females are more susceptible than males.

DOI 10.1016/j.scitotenv.2017.05.184
Citations Scopus - 48Web of Science - 33
Co-authors Mahmud Rahman
2017 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Toxicity of diesel water accommodated fraction toward microalgae, Pseudokirchneriella subcapitata and Chlorella sp MM3', ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 142 538-543 (2017) [C1]
DOI 10.1016/j.ecoenv.2017.04.052
Citations Scopus - 33Web of Science - 22
Co-authors Megh Mallavarapu, Kavitha Ramadass
2017 Mahbub KR, Krishnan K, Naidu R, Andrews S, Megharaj M, 'Mercury toxicity to terrestrial biota', ECOLOGICAL INDICATORS, 74 451-462 (2017) [C1]
DOI 10.1016/j.ecolind.2016.12.004
Citations Scopus - 83Web of Science - 66
Co-authors Megh Mallavarapu
2017 Subashchandrabose SR, Logeshwaran P, Venkateswarlu K, Naidu R, Megharaj M, 'Pyrene degradation by Chlorella sp MM3 in liquid medium and soil slurry: Possible role of dihydrolipoamide acetyltransferase in pyrene biodegradation', ALGAL RESEARCH-BIOMASS BIOFUELS AND BIOPRODUCTS, 23 223-232 (2017) [C1]
DOI 10.1016/j.algal.2017.02.010
Citations Scopus - 45Web of Science - 33
Co-authors Logeshwaran Panneerselvan, Megh Mallavarapu, Suresh Subashchandrabose
2017 Umeh AC, Duan L, Naidu R, Semple KT, 'Residual hydrophobic organic contaminants in soil: Are they a barrier to risk-based approaches for managing contaminated land?', ENVIRONMENT INTERNATIONAL, 98 18-34 (2017) [C1]
DOI 10.1016/j.envint.2016.09.025
Citations Scopus - 35Web of Science - 33
Co-authors Anthony Umeh
2017 Mandal S, Sarkar B, Bolan N, Ok YS, Naidu R, 'Enhancement of chromate reduction in soils by surface modified biochar', JOURNAL OF ENVIRONMENTAL MANAGEMENT, 186 277-284 (2017) [C1]
DOI 10.1016/j.jenvman.2016.05.034
Citations Scopus - 134Web of Science - 106
Co-authors Nanthi Bolan
2017 Usese A, Chukwu OL, Rahman MM, Naidu R, Islam S, Oyewo EO, 'Concentrations of arsenic in water and fish in a tropical open lagoon, Southwest-Nigeria: Health risk assessment', Environmental Technology and Innovation, 8 164-171 (2017) [C1]

This study assesses the concentrations of arsenic (As) in water, muscle tissue of four demersal fish species (Chrysichthys nigrodigitatus, Mugil cephalus, Liza falcipinnis and Bat... [more]

This study assesses the concentrations of arsenic (As) in water, muscle tissue of four demersal fish species (Chrysichthys nigrodigitatus, Mugil cephalus, Liza falcipinnis and Bathygobious soporator) and whole tissues of periwinkle (Tympanotonus fuscatus) in Lagos Lagoon, Nigeria. The observed mean total As concentration in water (1.29µgl-1) during the wet and dry seasons did not exceed the World Health Organization (WHO) guideline value of 10µgl-1. Among the examined biota, Tympanotonus fuscatus recorded higher As levels (2.31±0.24mgkg-1) and Chrysichthys nigrodigitatus recorded the least As content (0.67±0.08mgkg-1). A significant positive correlation (p<0.05) was observed between As concentrations in fish muscles and water during the dry and wet seasons. The health risks associated with human consumption of fish estimated using Target Hazard Quotient (THQ) were lower than the USEPA guideline value of 1 for all fish species examined except in populations that consume larger amounts of fish. However, higher THQ values (>2) were obtained for Tympanotonus fuscatus, suggesting the potential for non-carcinogenic health outcomes in adults after a prolonged period of consumption. This calls for continuous monitoring and enforcement of regulations to ensure safety of fishery resources from Lagos Lagoon.

DOI 10.1016/j.eti.2017.06.005
Citations Scopus - 6Web of Science - 5
Co-authors Mahmud Rahman
2017 Faustorilla V, Chen Z, Dharmarajan R, Naidu R, 'Improved method for the determination of polycyclic aromatic hydrocarbons in contaminated groundwater and soil samples at trace levels employing GC-MSD technique', Environmental Technology & Innovation, 8 218-232 (2017) [C1]
DOI 10.1016/j.eti.2017.07.003
Citations Scopus - 2Web of Science - 1
2017 Faustorilla MV, Dharmarajan R, Chen Z, Naidu R, 'Clean-up of the solid liquid extraction using certified reference material for soil TPH by GC-FID', Journal of Research Analytica, 3 81-87 (2017) [C1]
2017 Biswas B, Sarkar B, McClure S, Naidu R, 'Modified osmium tracer technique enables precise microscopic delineation of hydrocarbon-degrading bacteria in clay aggregates', Environmental Technology and Innovation, 7 12-20 (2017) [C1]

Clay minerals can support bacterial proliferation, induce the formation of clay¿bacterial aggregates, and finally a clay-based biofilm. However, how these abiotic and biotic entit... [more]

Clay minerals can support bacterial proliferation, induce the formation of clay¿bacterial aggregates, and finally a clay-based biofilm. However, how these abiotic and biotic entities interact in a microhabitat is not fully understood. Visualization of the clay¿bacterial micro-aggregate under scanning electron microscope (SEM) and profiling the associated elemental signature through energy dispersive X-ray spectroscopy (EDS) can potentially unravel the mechanisms of a complex clay¿bacterial interaction. Osmium (Os) was used previously to enhance the visualization of microbial substances, but the delineation of bacterial cells from clay particles in a micro-aggregate was not tried before. In this study, bacterial cells in a clay¿bacterial aggregate (Burkholderia sartisoli with montmorillonite and kaolinite) were specifically stained with osmium (Os) which served as the EDS tracer of the biotic component of the interaction. Simultaneously silicon (Si) provided the signature of the clay minerals. X-ray elemental profiling (line and field mapping) successfully delineated the individual components of the clay¿bacterial aggregate. Thus, this study presented a simple Os-based SEM-EDS technique which could facilitate the microanalysis of bacterial microhabitat within a complex environmental substrate.

DOI 10.1016/j.eti.2016.11.002
Citations Scopus - 6Web of Science - 4
Co-authors Bhaba Biswas
2017 Wijayawardena MAA, Naidu R, Megharaj M, Lamb D, Thavamani P, Kuchel T, 'Evaluation of relative bioaccessibility leaching procedure for an assessment of lead bioavailability in mixed metal contaminated soils', Environmental Technology and Innovation, 7 229-238 (2017) [C1]

This study investigates the effect of contaminant zinc (Zn) on lead (Pb) bioavailability and bioaccessibility in six contrasting soils spiked with 1500 mg Pb/kg and aged 12 months... [more]

This study investigates the effect of contaminant zinc (Zn) on lead (Pb) bioavailability and bioaccessibility in six contrasting soils spiked with 1500 mg Pb/kg and aged 12 months under laboratory conditions. Zn was added to the soils (7500 mgZn/kg soil) and aged for a further two weeks. In vivo studies were conducted using juvenile swine as a surrogate model for young children. Two compartment pharmacokinetic models were used to analyze the biological response produced by Pb oral solution and spiked soils. Absolute and relative bioavailability of Pb in soils (oral dose of 100 µ g Pb/kg body weight/day) were estimated by comparing them with intravenously administered soluble Pb salt (25 µ g Pb/kg/day) and orally administered the same Pb salt [Pb acetate =(CH3COO)2Pb·3H2O] administered to 3 juvenile pigs per treatment. Lead bioaccessibility was calculated using the in vitro RBALP (i.e. relative bioaccessibility leaching procedure) method. The in vitro results of RBALP were compared to in vivo relative Pb bioavailability to ascertain whether the changes in bioaccessibility correlated with the in vivo data. Although the in vivo Pb relative bioavailability (RB) in all soils except in MLA (Mount Lofty Acidic) revealed an increase (18%¿159%) in the presence of Zn, the in vitro RBALP bioaccessibility results indicated otherwise (1%¿38% decrease). In vivo RB of Pb in MLA declined by 37% in the presence of Zn. However, the RBALP in vitro bioaccessible Pb did not correlate with the relative bioavailabilities of Pb in the juvenile swine dosing experiment. Caution is therefore needed when predicting Pb bioavailability/bioaccessibility in the presence of metal mixtures. The literature contains much information on the correlation of metal and metalloid bioaccessibility with their bioavailability. There is, however, a paucity of studies investigating the effects of other metals on Pb and their IVIVC (in vitro and in vivo correlations). The current study addresses this knowledge gap by assessing in vivoand in vitro bioavailability of Pb in the presence of Zn.

DOI 10.1016/j.eti.2017.02.007
Citations Scopus - 5Web of Science - 4
Co-authors Thava Palanisami, Megh Mallavarapu, Ayanka Wijayawardena
2017 Usese A, Chukwu OL, Rahman MM, Naidu R, Islam S, Oyewo EO, 'Enrichment, contamination and geo-accumulation factors for assessing arsenic contamination in sediment of a Tropical Open Lagoon, Southwest Nigeria', Environmental Technology and Innovation, 8 126-131 (2017) [C1]

The presence of toxic heavy metals and metalloids in aquatic environments constitutes a major risk and there is an urgent need for continuous monitoring of such pollutants. This s... [more]

The presence of toxic heavy metals and metalloids in aquatic environments constitutes a major risk and there is an urgent need for continuous monitoring of such pollutants. This study assesses the concentrations of arsenic (As) in surface sediments from 15 locations on the Lagos Lagoon, Nigeria during the wet and dry seasons to determine the degree of contamination. The results showed that the mean total As concentration in sediment (2.44 mg kg-1 dry weight) did not exceed the Canadian Interim Sediment Quality Guideline (CISQG) value of 7.24 mg kg-1 dry weight during the wet and dry seasons. Based on the Sediment Quality Guidelines (SQGs) of the United States Environmental Protection Agency (USEPA) and ecological risk assessment using the enrichment factor (EF), contamination factor (CF) and geo-accumulation index (Igeo), the study's results indicate two things: firstly, low to moderate and significant levels of enrichment from As; and secondly, low to moderate degree of contamination in Lagos Lagoon during the study period.

DOI 10.1016/j.eti.2017.06.006
Citations Scopus - 17Web of Science - 15
Co-authors Mahmud Rahman
2017 Rusmin R, Sarkar B, Tsuzuki T, Kawashima N, Naidu R, 'Removal of lead from aqueous solution using superparamagnetic palygorskite nanocomposite: Material characterization and regeneration studies', Chemosphere, 186 1006-1015 (2017) [C1]

A palygorskite-iron oxide nanocomposite (Pal-IO) was synthesized in situ by embedding magnetite into the palygorskite structure through co-precipitation method. The physico-chemic... [more]

A palygorskite-iron oxide nanocomposite (Pal-IO) was synthesized in situ by embedding magnetite into the palygorskite structure through co-precipitation method. The physico-chemical characteristics of Pal-IO and their pristine components were examined through various spectroscopic and micro-analytical techniques. Batch adsorption experiments were conducted to evaluate the performance of Pal-IO in removing Pb(II) from aqueous solution. The surface morphology, magnetic recyclability and adsorption efficiency of regenerated Pal-IO using desorbing agents HCl (Pal-IO-HCl) and ethylenediaminetetraacetic acid disodium salt (EDTA-Na2) (Pal-IO-EDTA) were compared. The nanocomposite showed a superparamagnetic property (magnetic susceptibility: 20.2 emu g-1) with higher specific surface area (99.8 m2 g-1) than the pristine palygorskite (49.4 m2 g-1) and iron oxide (72.6 m2 g-1). Pal-IO showed a maximum Pb(II) adsorption capacity of 26.6 mg g-1 (experimental condition: 5 g L-1 adsorbent loading, 150 agitations min-1, initial Pb(II) concentration from 20 to 500 mg L-1, at 25 °C) with easy separation of the spent adsorbent. The adsorption data best fitted to the Langmuir isotherm model (R2 = 0.9995) and pseudo-second order kinetic model (R2 = 0.9945). Pb(II) desorption using EDTA as the complexing agent produced no disaggregation of Pal-IO crystal bundles, and was able to preserve the composite's magnetic recyclability. Pal-IO-EDTA exhibited almost 64% removal capacity after three cycles of regeneration and preserved the nanocomposite's structural integrity and magnetic properties (15.6 emu g-1). The nanocomposite holds advantages as a sustainable material (easily separable and recyclable) for potential application in purifying heavy metal contaminated wastewaters.

DOI 10.1016/j.chemosphere.2017.08.036
Citations Scopus - 29Web of Science - 20
2017 Kader M, Lamb DT, Wang L, Megharaj M, Naidu R, 'Zinc-arsenic interactions in soil: Solubility, toxicity and uptake', Chemosphere, 187 357-367 (2017) [C1]

Arsenic (As) and zinc (Zn) are common co-contaminants in mining impacted soils. Their interaction on solubility and toxicity when present concurrently is not well understood in na... [more]

Arsenic (As) and zinc (Zn) are common co-contaminants in mining impacted soils. Their interaction on solubility and toxicity when present concurrently is not well understood in natural systems. The aim of this study was to observe their interaction in solubility (soil-solution), bioaccumulation (shoot uptake) and toxicity to cucumber (Cucumis sativa L) conducting 4 weeks pot study in 5 different soils spiked with As (0, 2, 4, 8 to 1024 mg kg-1) individually and with Zn at two phytotoxic doses. The As pore-water concentration was significantly reduced (df = 289, Adjusted R2 = 0.84, p < 0.01) in the presence of Zn in the whole dataset, whereas Zn and Zn2+ activity in pore-water was reduced significantly only in the two alkaline soils. This outcome may be due to adsorption/surface precipitation or tertiary bridging complexation. No homogenous precipitation of zinc arsenate could be established using electron microscopy, XRD or even equilibrium calculations. For bioaccumulation phase, no significant effect of Zn on As uptake was observed except acidic MG soil whereas, Zn uptake was significantly reduced (p < 0.05) by As in whole dataset. However, an additive response was observed mostly except acidic MG soil. The synergistic response (more than additive) was predominant in this soil for a wide range of inhibition concentration (0¿80%) at both Zn EC10 and EC50 levels. Since additive response is mostly considered in risk assessment for mixtures, precautions should be implemented for assessment of toxicity for As-Zn mixture in acidic soil due to their synergistic response in some soils.

DOI 10.1016/j.chemosphere.2017.08.093
Citations Scopus - 24Web of Science - 23
Co-authors Megh Mallavarapu, Liang Wang
2017 Fang C, Megharaj M, Naidu R, 'Electrochemical Advanced Oxidation Processes (EAOP) to degrade per- and polyflluoroalkyl substances (PFASs)', JOURNAL OF ADVANCED OXIDATION TECHNOLOGIES, 20 (2017) [C1]
DOI 10.1515/jaots-2017-0014
Citations Scopus - 39Web of Science - 28
Co-authors Cheng Fang, Megh Mallavarapu
2017 Singh G, Kim IY, Lakhi KS, Joseph S, Srivastava P, Naidu R, Vinu A, 'Heteroatom functionalized activated porous biocarbons and their excellent performance for CO2 capture at high pressure', JOURNAL OF MATERIALS CHEMISTRY A, 5 21196-21204 (2017)
DOI 10.1039/c7ta07186h
Citations Scopus - 87Web of Science - 73
Co-authors Ajayan Vinu, Gurwinder Singh
2017 Kuppusamy S, Thavamani P, Venkateswarlu K, Lee YB, Naidu R, Megharaj M, 'Remediation approaches for polycyclic aromatic hydrocarbons (PAHs) contaminated soils: Technological constraints, emerging trends and future directions', CHEMOSPHERE, 168 944-968 (2017) [C1]
DOI 10.1016/j.chemosphere.2016.10.115
Citations Scopus - 549Web of Science - 361
Co-authors Megh Mallavarapu, Thava Palanisami
2017 Faustorilla MV, Dharmarajan R, Chen Z, Naidu R, 'Fractionation of total petroleum hydrocarbons in soil by SPE-GC for toxicity studies to Eisenia fetida', Journal of Chromatography & Separation Techniques, 8 44-44 (2017)
DOI 10.4172/2157-7064.C1.037
2017 Mahbub KR, Subashchandrabose SR, Krishnan K, Naidu R, Megharaj M, 'Mercury alters the bacterial community structure and diversity in soil even at concentrations lower than the guideline values', APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 101 2163-2175 (2017) [C1]
DOI 10.1007/s00253-016-7965-y
Citations Scopus - 34Web of Science - 27
Co-authors Suresh Subashchandrabose, Megh Mallavarapu
2017 Fang C, Dharmarajan R, Mallavarapu M, Naidu R, 'Gold nanoparticle-based optical sensors for selected anionic contaminants', Trends in Analytical Chemistry, 86 143-154 (2017) [C1]
DOI 10.1016/j.trac.2016.10.008
Citations Scopus - 66Web of Science - 50
Co-authors Megh Mallavarapu, Cheng Fang
2017 Matheyarasu R, Sheshadri B, Bolan NS, Naidu R, 'Nutrient Budgeting as an Approach to Assess and Manage the Impacts of Long-Term Irrigation Using Abattoir Wastewater', WATER AIR AND SOIL POLLUTION, 228 (2017) [C1]
DOI 10.1007/s11270-017-3542-y
Citations Scopus - 2
Co-authors Nanthi Bolan
2017 Mahbub KR, Kader M, Krishnan K, Labbate M, Naidu R, Megharaj M, 'Toxicity of Inorganic Mercury to Native Australian Grass Grown in Three Different Soils', BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 98 850-855 (2017) [C1]
DOI 10.1007/s00128-017-2096-4
Citations Scopus - 10Web of Science - 8
Co-authors Megh Mallavarapu
2017 Bolan S, Kunhikrishnan A, Seshadri B, Choppala G, Naidu R, Bolan NS, et al., 'Sources, distribution, bioavailability, toxicity, and risk assessment of heavy metal(loid)s in complementary medicines', ENVIRONMENT INTERNATIONAL, 108 103-118 (2017) [C1]
DOI 10.1016/j.envint.2017.08.005
Citations Scopus - 79Web of Science - 55
Co-authors Girish Choppala, Nanthi Bolan
2017 Islam S, Rahman MM, Duan L, Islam MR, Kuchel T, Naidu R, 'Variation in arsenic bioavailability in rice genotypes using swine model: An animal study', SCIENCE OF THE TOTAL ENVIRONMENT, 599 324-331 (2017) [C1]
DOI 10.1016/j.scitotenv.2017.04.215
Citations Scopus - 32Web of Science - 26
Co-authors Mahmud Rahman
2016 Mahbub K, Krishnan, Mallavarapu, Naidu, 'Mercury Inhibits Soil Enzyme Activity in a Lower Concentration than the Guideline Value', Bulletin of Environmental Contamination and Toxicology, 96 76-82 (2016) [C1]
DOI 10.1007/s00128-015-1664-8
Citations Scopus - 23Web of Science - 22
Co-authors Megh Mallavarapu
2016 Venkidusamy K, Megharaj M, Marzorati M, Lockington R, Naidu R, 'Enhanced removal of petroleum hydrocarbons using a bioelectrochemical remediation system with pre-cultured anodes', Science of the Total Environment, 539 61-69 (2016) [C1]

Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon... [more]

Bioelectrochemical remediation (BER) systems such as microbial fuel cells (MFCs) have recently emerged as a green technology for the effective remediation of petroleum hydrocarbon contaminants (PH) coupled with simultaneous energy recovery. Recent research has shown that biofilms previously enriched for substrate degrading bacteria resulted in excellent performance in terms of substrate removal and electricity generation but the effects on hydrocarbon contaminant degradation were not examined. Here we investigate the differences between enriched biofilm anodes and freshly inoculated new anodes in diesel fed single chamber mediatorless microbial fuel cells (DMFC) using various techniques for the enhancement of PH contaminant remediation with concomitant electricity generation. An anodophilic microbial consortium previously selected for over a year through continuous culturing with a diesel concentration of about 800mgl<sup>-1</sup> and which now showed complete removal of this concentration of diesel within 30days was compared to that of a freshly inoculated new anode MFC (showing 83.4% removal of diesel) with a simultaneous power generation of 90.81mW/m<sup>2</sup> and 15.04mW/m<sup>2</sup> respectively. The behaviour of pre-cultured anodes at a higher concentration of PH (8000mgl<sup>-1</sup>) was also investigated. Scanning electron microscopy observation revealed a thick biofilm covering the pre-cultured anodic electrode but not the anode from the freshly inoculated MFC. High resolution imaging showed the presence of thin 60nm diametre pilus-like projections emanating from the cells. Anodic microbial community profiling confirmed that the selection for diesel degrading exoelectrogenic bacteria had occurred. Identification of a biodegradative gene (alkB) provided strong evidence of the catabolic pathway used for diesel degradation in the DMFCs.

DOI 10.1016/j.scitotenv.2015.08.098
Citations Scopus - 57Web of Science - 48
Co-authors Megh Mallavarapu
2016 Naidu R, Arias V, Liu Y, Jit J, 'Emerging contaminants in the environment: Risk-based analysis for better management', Chemosphere, 154 350-357 (2016) [C1]
DOI 10.1016/j.chemosphere.2016.03.068
Citations Scopus - 184Web of Science - 132
Co-authors Yanju Liu
2016 Subramaniyam V, Subashchandrabose SR, Thavamani P, Chen Z, Krishnamurti GSR, Naidu R, Megharaj M, 'Toxicity and bioaccumulation of iron in soil microalgae', Journal of Applied Phycology, 28 2767-2776 (2016) [C1]

Microalgae are extensively used in the remediation of heavy metals like iron. However, factors like toxicity, bioavailability and iron speciation play a major role in its removal ... [more]

Microalgae are extensively used in the remediation of heavy metals like iron. However, factors like toxicity, bioavailability and iron speciation play a major role in its removal by microalgae. Thus, in this study, toxicity of three different iron salts (FeSO4, FeCl3 and Fe(NO3)3) was evaluated towards three soil microalgal isolates, Chlorella sp. MM3, Chlamydomonas sp. MM7 and Chlorococcum sp. MM11. Interestingly, all the three iron salts gave different EC50 concentrations; however, ferric nitrate was found to be significantly more toxic followed by ferrous sulphate and ferric chloride. The EC50 analysis revealed that Chlorella sp. was significantly resistant to iron compared to other microalgae. However, almost 900¿µg¿g-1 iron was accumulated by Chlamydomonas sp. grown with 12¿mg¿L-1 ferric nitrate as an iron source when compared to other algae and iron salts. The time-course bioaccumulation confirmed that all the three microalgae adsorb the ferric salts such as ferric nitrate and ferric chloride more rapidly than ferrous salt, whereas intracellular accumulation was found to be rapid for ferrous salts. However, the amount of iron accumulated or adsorbed by algae, irrespective of species, from ferrous sulphate medium is comparatively lower than ferric chloride and ferric nitrate medium. The Fourier transform infrared spectroscopy (FTIR) analysis shows that the oxygen atom and P = O group of polysaccharides present in the cell wall of algae played a major role in the bioaccumulation of iron ions by algae.

DOI 10.1007/s10811-016-0837-0
Citations Scopus - 29Web of Science - 18
Co-authors Suresh Subashchandrabose, Megh Mallavarapu, Thava Palanisami
2016 Biswas B, Sarkar B, Mandal A, Naidu R, 'Specific adsorption of cadmium on surface-engineered biocompatible organoclay under metal-phenanthrene mixed-contamination', WATER RESEARCH, 104 119-127 (2016) [C1]
DOI 10.1016/j.watres.2016.08.009
Citations Scopus - 21Web of Science - 20
Co-authors Bhaba Biswas
2016 Luo F, Yang D, Chen Z, Megharaj M, Naidu R, 'Characterization of bimetallic Fe/Pd nanoparticles by grape leaf aqueous extract and identification of active biomolecules involved in the synthesis', SCIENCE OF THE TOTAL ENVIRONMENT, 562 526-532 (2016) [C1]
DOI 10.1016/j.scitotenv.2016.04.060
Citations Scopus - 39Web of Science - 26
Co-authors Megh Mallavarapu
2016 Nirola R, Megharaj M, Saint C, Aryal R, Thavamani P, Venkateswarlu K, et al., 'Metal bioavailability to Eisenia fetida through copper mine dwelling animal and plant litter, a new challenge on contaminated environment remediation', INTERNATIONAL BIODETERIORATION & BIODEGRADATION, 113 208-216 (2016) [C1]
DOI 10.1016/j.ibiod.2016.03.007
Citations Scopus - 21Web of Science - 18
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Kuppusamy S, Thavamani P, Megharaj M, Venkateswarlu K, Lee YB, Naidu R, 'Oak (Quercus robur) Acorn Peel as a Low-Cost Adsorbent for Hexavalent Chromium Removal from Aquatic Ecosystems and Industrial Effluents', Water, Air, and Soil Pollution, 227 (2016) [C1]

The efficiency of low-cost, abundantly available local forestry waste, oak (Quercus robur) acorn peel (OP), to remove toxic Cr(VI) from aqueous solutions was studied in a batch sy... [more]

The efficiency of low-cost, abundantly available local forestry waste, oak (Quercus robur) acorn peel (OP), to remove toxic Cr(VI) from aqueous solutions was studied in a batch system as a function of contact time, adsorbate concentration, adsorbent dosage, and pH. In an equilibrium time of 420 min, the maximum Cr removal by OP at pH 2 and 10 was 100 and 97 %, respectively. The sorption data fitted well with Langmuir adsorption model. Evaluation using Langmuir expression presented a monolayer sorption capacity of 47.39 mg g-1 with an equilibrium sorbent dose of 5 g L-1 and pH 7. Uptake of Cr by OP was described by pseudo-second-order chemisorption model. ICP-OES, LC-ICPMS analysis of the aqueous and solid phases revealed that the mechanism of Cr(VI) removal is by 'integrated adsorption and reduction' mechanism. ESEM-EDX and XRD analysis of OP before and after adsorption also confirmed that both adsorption and reduction of Cr(VI) to less toxic Cr3+ forms followed by complexation onto the adsorbent surface contributed to the removal of Cr(VI). Consistent with batch studies, OP effectively removed (>95 %) Cr from the real water samples collected from lake and sea. The results of this study illustrate that OP could be an economical, green, and effective biomaterial for Cr(VI) removal from natural aquatic ecosystems and industrial effluents.

DOI 10.1007/s11270-016-2760-z
Citations Scopus - 38Web of Science - 26
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Mahbub KR, Krishnan K, Megharaj M, Naidu R, 'Bioremediation potential of a highly mercury resistant bacterial strain Sphingobium SA2 isolated from contaminated soil', Chemosphere, 144 330-337 (2016) [C1]

A mercury resistant bacterial strain, SA2, was isolated from soil contaminated with mercury. The 16S rRNA gene sequence of this isolate showed 99% sequence similarity to the gener... [more]

A mercury resistant bacterial strain, SA2, was isolated from soil contaminated with mercury. The 16S rRNA gene sequence of this isolate showed 99% sequence similarity to the genera Sphingobium and Sphingomonas of a-proteobacteria group. However, the isolate formed a distinct phyletic line with the genus Sphingobium suggesting the strain belongs to Sphingobium sp. Toxicity studies indicated resistance to high levels of mercury with estimated EC50 values 4.5 mg L-1 and 44.15 mg L-1 and MIC values 5.1 mg L-1 and 48.48 mg L-1 in minimal and rich media, respectively. The strain SA2 was able to volatilize mercury by producing mercuric reductase enzyme which makes it potential candidate for remediating mercury. ICP-QQQ-MS analysis of Hg supplemented culture solutions confirmed that almost 79% mercury in the culture suspension was volatilized in 6 h. A very small amount of mercury was observed to accumulate in cell pellets which was also evident according to ESEM-EDX analysis. The mercuric reductase gene merA was amplified and sequenced. The deduced amino acid sequence demonstrated sequence homology with a-proteobacteria and Ascomycota group.

DOI 10.1016/j.chemosphere.2015.08.061
Citations Scopus - 73Web of Science - 56
Co-authors Megh Mallavarapu
2016 Dong Z, Yan K, Liu Y, Naidu R, Duan L, Wijayawardena A, et al., 'A meta-analysis to correlate lead bioavailability and bioaccessibility and predict lead bioavailability', Environment International, 92-93 139-145 (2016) [C1]
DOI 10.1016/j.envint.2016.04.009
Citations Scopus - 19Web of Science - 15
Co-authors Yanju Liu, Mahmud Rahman, Ayanka Wijayawardena
2016 Kuppusamy S, Thavamani P, Megharaj M, Venkateswarlu K, Lee YB, Naidu R, 'Pyrosequencing analysis of bacterial diversity in soils contaminated long-term with PAHs and heavy metals: Implications to bioremediation', Journal of Hazardous Materials, 317 169-179 (2016) [C1]

Diversity, distribution and composition of bacterial community of soils contaminated long-term with both polycyclic aromatic hydrocarbons (PAHs) and heavy metals were explored for... [more]

Diversity, distribution and composition of bacterial community of soils contaminated long-term with both polycyclic aromatic hydrocarbons (PAHs) and heavy metals were explored for the first time following 454 pyrosequencing. Strikingly, the complete picture of the Gram positive (+ve) and Gram negative (-ve) bacterial profile obtained in our study illustrates novel postulates that include: (1) Metal-tolerant and PAH-degrading Gram -ves belonging to the class Alphaproteobacteria persist relatively more in the real contaminated sites compared to Gram +ves, (2) Gram +ves are not always resistant to heavy metal toxicity, (3) Stenotrophomonas followed by Burkholderia and Pseudomonas are the dominant genera of PAH degraders with high metabolic activity in long-term contaminated soils, (4) Actinobacteria is the predominant group among the Gram +ves in soils contaminated with high molecular weight PAHs that co-exist with toxic heavy metals like Pb, Cu and Zn, (5) Microbial communities are nutrient-driven in natural environments and (6) Catabolically potential Gram +/-ves with diverse applicability to remediate the real contaminated sites evolve eventually in the historically-polluted soils. Thus, the most promising indigenous Gram +/-ve strains from the long-term contaminated sites with increased catabolic potential, enzymatic activity and metal tolerance need to be harnessed for mixed contaminant cleanups.

DOI 10.1016/j.jhazmat.2016.05.066
Citations Scopus - 111Web of Science - 94
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Mayilswami S, Krishnan K, Megharaj M, Naidu R, 'Gene expression profile changes in Eisenia fetida chronically exposed to PFOA', Ecotoxicology, 25 759-769 (2016) [C1]

Eisenia fetida is a terrestrial organism, which can be used to diagnose sub-lethal concentrations of PFOA by using molecular biomarkers. In order to identify potential molecular b... [more]

Eisenia fetida is a terrestrial organism, which can be used to diagnose sub-lethal concentrations of PFOA by using molecular biomarkers. In order to identify potential molecular biomarkers, we have exposed E.¿fetida to 10¿mg/kg of PFOA in soil for 8¿months. The mRNA isolation, sequencing, transcriptome assembly followed by differential gene expression studies have revealed that genes that are involved in apoptotic process, reproduction, calcium signalling, neuronal development and lipid metabolism are predominantly affected. Highly specific genes that are altered by PFOA can be further validated and used as biomarker to detect sub-lethal concentrations of PFOA in the soil.

DOI 10.1007/s10646-016-1634-x
Citations Scopus - 17Web of Science - 13
Co-authors Megh Mallavarapu
2016 Dong Z, Liu CX, Liu Y, Yan K, Semple KT, Naidu R, 'Using publicly available data, a physiologically-based pharmacokinetic model and Bayesian simulation to improve arsenic non-cancer dose-response', Environment International, 92-93 239-246 (2016) [C1]

Publicly available data can potentially examine the relationship between environmental exposure and public health, however, it has not yet been widely applied. Arsenic is of envir... [more]

Publicly available data can potentially examine the relationship between environmental exposure and public health, however, it has not yet been widely applied. Arsenic is of environmental concern, and previous studies mathematically parameterized exposure duration to create a link between duration of exposure and increase in risk. However, since the dose metric emerging from exposure duration is not a linear or explicit variable, it is difficult to address the effects of exposure duration simply by using mathematical functions. To relate cumulative dose metric to public health requires a lifetime physiologically-based pharmacokinetic (PBPK) model, yet this model is not available at a population level. In this study, the data from the U.S. total diet study (TDS, 2006-2011) was employed to assess exposure: daily dietary intakes for total arsenic (tAs) and inorganic arsenic (iAs) were estimated to be 0.15 and 0.028 µg/kg/day, respectively. Meanwhile, using National Health and Nutrition Examination Survey (NHANES, 2011-2012) data, the fraction of urinary As(III) levels (geometric mean: 0.31 µg/L) in tAs (geometric mean: 7.75 µg/L) was firstly reported to be approximately 4%. Together with Bayesian technique, the assessed exposure and urinary As(III) concentration were input to successfully optimize a lifetime population PBPK model. Finally, this optimized PBPK model was used to derive an oral reference dose (Rfd) of 0.8 µg/kg/day for iAs exposure. Our study also suggests the previous approach (by using mathematical functions to account for exposure duration) may result in a conservative Rfd estimation.

DOI 10.1016/j.envint.2016.03.035
Citations Scopus - 16Web of Science - 14
Co-authors Yanju Liu
2016 Kumar M, Rahman MM, Ramanathan AL, Naidu R, 'Arsenic and other elements in drinking water and dietary components from the middle Gangetic plain of Bihar, India: Health risk index', Science of the Total Environment, 539 125-134 (2016) [C1]

This study investigates the level of contamination and health risk assessment for arsenic (As) and other elements in drinking water, vegetables and other food components in two bl... [more]

This study investigates the level of contamination and health risk assessment for arsenic (As) and other elements in drinking water, vegetables and other food components in two blocks (Mohiuddinagar and Mohanpur) from the Samastipur district, Bihar, India. Groundwater (80%) samples exceeded the World Health Organization (WHO) guideline value (10. µg/L) of As while Mn exceeded the previous WHO limit of 400. µg/L in 28% samples. The estimated daily intake of As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn from drinking water and food components were 169, 19, 26, 882, 4645, 14582, 474, 1449 and 12,955. µg, respectively (estimated exposure 3.70, 0.41, 0.57, 19.61, 103.22, 324.05, 10.53, 32.21 and 287.90. µg per kg bw, respectively). Twelve of 15 cooked rice contained high As concentration compared to uncooked rice. Water contributes (67%) considerable As to daily exposure followed by rice and vegetables. Whereas food is the major contributor of other elements to the dietary exposure. Correlation and principal component analysis (PCA) indicated natural source for As but for other elements, presence of diffused anthropogenic activities were responsible. The chronic daily intake (CDI) and health risk index (HRI) were also estimated from the generated data. The HRI were >. 1 for As in drinking water, vegetables and rice, for Mn in drinking water, vegetables, rice and wheat, for Pb in rice and wheat indicated the potential health risk to the local population. An assessment of As and other elements of other food components should be conducted to understand the actual health hazards caused by ingestion of food in people residing in the middle Gangetic plain.

DOI 10.1016/j.scitotenv.2015.08.039
Citations Scopus - 152Web of Science - 121
Co-authors Mahmud Rahman
2016 Bolan S, Naidu R, Kunhikrishnan A, Seshadri B, Ok YS, Palanisami T, et al., 'Speciation and bioavailability of lead in complementary medicines', Science of the Total Environment, 539 304-312 (2016) [C1]

Complementary medicines have associated risks which include toxic heavy metal(loid) and pesticide contamination. The objective of this study was to examine the speciation and bioa... [more]

Complementary medicines have associated risks which include toxic heavy metal(loid) and pesticide contamination. The objective of this study was to examine the speciation and bioavailability of lead (Pb) in selected complementary medicines. Six herbal and six ayurvedic medicines were analysed for: (i) total heavy metal(loid) contents including arsenic (As), cadmium (Cd), Pb and mercury (Hg); (ii) speciation of Pb using sequential fractionation and extended x-ray absorption fine structure (EXAFS) techniques; and (iii) bioavailability of Pb using a physiologically-based in vitro extraction test (PBET). The daily intake of Pb through the uptake of these medicines was compared with the safety guidelines for Pb. The results indicated that generally ayurvedic medicines contained higher levels of heavy metal(loid)s than herbal medicines with the amount of Pb much higher than the other metal(loid)s. Sequential fractionation indicated that while organic-bound Pb species dominated the herbal medicines, inorganic-bound Pb species dominated the ayurvedic medicines. EXAFS data indicated the presence of various Pb species in ayurvedic medicines. This implies that Pb is derived from plant uptake and inorganic mineral input in herbal and ayurvedic medicines, respectively. Bioavailability of Pb was higher in ayurvedic than herbal medicines, indicating that Pb added as a mineral therapeutic input is more bioavailable than that derived from plant uptake. There was a positive relationship between soluble Pb fraction and bioavailability indicating that solubility is an important factor controlling bioavailability. The daily intake values for Pb as estimated by total and bioavailable metal(loid) contents are likely to exceed the safe threshold level in certain ayurvedic medicines. This research demonstrated that Pb toxicity is likely to result from the regular intake of these medicines which requires further investigation.

DOI 10.1016/j.scitotenv.2015.08.124
Citations Scopus - 17Web of Science - 15
Co-authors Thava Palanisami
2016 Abbasian F, Lockington R, Palanisami T, Megharaj M, Naidu R, 'Multiwall carbon nanotubes increase the microbial community in crude oil contaminated fresh water sediments', Science of the Total Environment, 539 370-380 (2016) [C1]

Since crude oil contamination is one of the biggest environmental concerns, its removal from contaminated sites is of interest for both researchers and industries. In situ bioreme... [more]

Since crude oil contamination is one of the biggest environmental concerns, its removal from contaminated sites is of interest for both researchers and industries. In situ bioremediation is a promising technique for decreasing or even eliminating crude oil and hydrocarbon contamination. However, since these compounds are potentially toxic for many microorganisms, high loads of contamination can inhibit the microbial community and therefore reduce the removal rate. Therefore, any strategy with the ability to increase the microbial population in such circumstances can be of promise in improving the remediation process. In this study, multiwall carbon nanotubes were employed to support microbial growth in sediments contaminated with crude oil. Following spiking of fresh water sediments with different concentrations of crude oil alone and in a mixture with carbon nanotubes for 30. days, the microbial profiles in these sediments were obtained using FLX-pyrosequencing. Next, the ratios of each member of the microbial population in these sediments were compared with those values in the untreated control sediment. This study showed that combination of crude oil and carbon nanotubes can increase the diversity of the total microbial population. Furthermore, these treatments could increase the ratios of several microorganisms that are known to be effective in the degradation of hydrocarbons.

DOI 10.1016/j.scitotenv.2015.09.031
Citations Scopus - 33Web of Science - 22
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Yirsaw BD, Mayilswami S, Megharaj M, Chen Z, Naidu R, 'Effect of zero valent iron nanoparticles to Eisenia fetida in three soil types', Environmental Science and Pollution Research, 23 9822-9831 (2016) [C1]

In this study, the influence of soil types on the effect of the commercial form of C-nZVI on tissue concentrations, cellular component, reproduction outcome in Eisenia fetida, and... [more]

In this study, the influence of soil types on the effect of the commercial form of C-nZVI on tissue concentrations, cellular component, reproduction outcome in Eisenia fetida, and the soil health was investigated. C-nZVI at concentration level of 3¿g¿kg-1 soil showed no effect on the survival of E. fetida in the three soil types. However, varying effects such as concentration-dependent increase in tissue iron concentration, lipid peroxidation, and damage to DNA molecules by C-nZVI were observed. C-nZVI at an exposure concentration of 60¿mg¿kg-1 soil induced oxidative stress in E. fetida. Tissue Fe concentration appeared correlated to the DNA damage. Oxidative stress and DNA damage may explain the toxicity mechanisms of nZVI to E. fetida. [Figure not available: see fulltext.].

DOI 10.1007/s11356-016-6193-4
Citations Scopus - 27Web of Science - 18
Co-authors Megh Mallavarapu
2016 Nirola R, Megharaj M, Aryal R, Naidu R, 'Screening of metal uptake by plant colonizers growing on abandoned copper mine in Kapunda, South Australia', International Journal of Phytoremediation, 18 399-405 (2016) [C1]

© 2016, © Taylor &amp; Francis Group, LLC.Systematic site survey for sample collection and analysis was conducted at a derelict copper (Cu) mine at Kapunda, South Australia. Cu co... [more]

© 2016, © Taylor & Francis Group, LLC.Systematic site survey for sample collection and analysis was conducted at a derelict copper (Cu) mine at Kapunda, South Australia. Cu concentrations in the soils at this former mine ranged from 65¿10107¿mg kg-1. The pH and EC varied widely in the 3.9¿8.4 and 152¿7311¿µS ranges, respectively. Nine plant species growing over the copper mine site were selected to screen for metal uptake to determine their suitability for phytoremediation. The Australian native tree species Eucalyptus camaldulensis indicated enrichment factor (EF) of 2.17, 1.89, and 1.30 for Cu, Zn, and Pb, respectively, suggesting that this species of tree can accumulate these metals to some degree. The stress-resistant exotic olive, Olea europaea exhibited EF of = 0.01 for Cu, Cd, and Pb, and 0.29 for Zn, which is characteristic of an excluder plant. Acacia pycnantha, the Australian pioneer legume species with EF 0.03, 0.80, 0.32, and 0.01 for Cu, Zn, Cd, and Pb, respectively, emerged as another strong metal excluder and consequently as an ideal metal stabilizer.

DOI 10.1080/15226514.2015.1109599
Citations Scopus - 31Web of Science - 25
Co-authors Megh Mallavarapu
2016 Abbasian F, Palanisami T, Megharaj M, Naidu R, Lockington R, Ramadass K, 'Microbial diversity and hydrocarbon degrading gene capacity of a crude oil field soil as determined by metagenomics analysis', Biotechnology Progress, 32 638-648 (2016) [C1]

© 2016 American Institute of Chemical Engineers Soils contaminated with crude oil are rich sources of enzymes suitable for both degradation of hydrocarbons through bioremediation ... [more]

© 2016 American Institute of Chemical Engineers Soils contaminated with crude oil are rich sources of enzymes suitable for both degradation of hydrocarbons through bioremediation processes and improvement of crude oil during its refining steps. Due to the long term selection, crude oil fields are unique environments for the identificati on of microorganisms with the ability to produce these enzymes. In this metagenomic study, based on Hiseq Illumina sequencing of samples obtained from a crude oil field and analysis of data on MG-RAST, Actinomycetales (9.8%) were found to be the dominant microorganisms, followed by Rhizobiales (3.3%). Furthermore, several functional genes were found in this study, mostly belong to Actinobacteria (12.35%), which have a role in the metabolism of aliphatic and aromatic hydrocarbons (2.51%), desulfurization (0.03%), element shortage (5.6%), and resistance to heavy metals (1.1%). This information will be useful for assisting in the application of microorganisms in the removal of hydrocarbon contamination and/or for improving the quality of crude oil. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:638¿648, 2016.

DOI 10.1002/btpr.2249
Citations Scopus - 52Web of Science - 41
Co-authors Megh Mallavarapu, Thava Palanisami, Kavitha Ramadass
2016 Luo F, Chen Z, Megharaj M, Naidu R, 'Simultaneous removal of trichloroethylene and hexavalent chromium by green synthesized agarose-Fe nanoparticles hydrogel', Chemical Engineering Journal, 294 290-297 (2016) [C1]

The development of highly efficient, eco-friendly and cost-effective remediation technology to remove mixed contaminants is now in progress. Here, agarose-Fe nanoparticles (NPs) h... [more]

The development of highly efficient, eco-friendly and cost-effective remediation technology to remove mixed contaminants is now in progress. Here, agarose-Fe nanoparticles (NPs) hydrogel were produced via two green steps to remove mixed contaminants, specifically trichloroethylene (TCE) and hexavalent chromium (Cr(VI)). Approx. 84.9% of Cr(VI) and 93.8% of TCE were simultaneously removed over 24 h in their co-existing solution, while 94.1% of Cr(VI) and 97.2% of TCE were separately removed by agarose-Fe NPs hydrogel. Scanning Electron Microscopy (SEM) suggested that the macroporosity of agarose-Fe NPs hydrogel facilitated the mass transfer between agarose-Fe NPs hydrogels and mixed contaminants, and that Fe NPs were uniformly immobilized into the hydrogel. X-ray Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) provided evidence supporting the co-removal mechanism. XPS result indicated that: (1) chemical reduction played a role in the removal of both Cr(VI) and TCE; and (2) iron oxides and Fe(III)-Cr(III) complexes might be formed after reaction. FTIR result showed that some functional groups were involved in the removal process. Moreover, the presence of iron oxides were confirmed by FTIR. Both SEM and XPS results verified that encapsulation could describe such immobilization of Fe NPs using agarose. Finally, the kinetics study supported the removal mechanism. Such encapsulation of Fe NPs via a green strategy is simple, quick, and cost-effective, making in situ remediation of mixed contaminants more favorable.

DOI 10.1016/j.cej.2016.03.005
Citations Scopus - 80Web of Science - 58
Co-authors Megh Mallavarapu
2016 Bello O, Naidu R, Rahman MM, Liu Y, Dong Z, 'Lead concentration in the blood of the general population living near a lead-zinc mine site, Nigeria: Exposure pathways', Science of the Total Environment, 542 908-914 (2016) [C1]

Lead (Pb) poisoning in children is a major public health catastrophe worldwide. This report summarises both exposure pathways and blood Pb levels in children below 7. years of age... [more]

Lead (Pb) poisoning in children is a major public health catastrophe worldwide. This report summarises both exposure pathways and blood Pb levels in children below 7. years of age and adults (above 18. years) from the Adudu community living near a lead-zinc mine in Nasawara, Nigeria. The average and median blood Pb levels in children and adults were 2.1 and 1.3 µg/dL, 3.1 and 1.8 µg/dL, respectively. However, Pb in 14% of adults' blood exceeded 5. µg/dL, which is the recommended threshold blood Pb concentration in adults as established by the Centers for Disease Control and Prevention (CDC). Furthermore 68% of adults' blood exceeded blood Pb action level of 2 µg/dL. For children, 11.4% and 31% of the blood samples exceeded 5 µg/dL and 2 µg/dL, respectively, while no safe blood Pb level in children has been recommended. In Nasawara, a significant difference (p< 0.05) was observed between the various age groups in children with 2-4 years old having the highest levels and 6. year old children having the lowest Pb levels. Although this study did not detect elevated levels of Pb in children's blood in regions such as Zamfara, Nigeria and Kabwe, Zambia, a high percentage of samples exceeded 2 µg/dL. Soils, floor dusts, water and crops also reveal that Pb contamination in the study area could potentially be the major cause of blood Pb in the community exposed to mining. This study also observed a significant correlation between water Pb levels of adults and blood Pb levels, suggesting that water is the major exposure pathway. This analysis highlights the need to properly manage mining activities so that the health of communities living in the vicinity of a Pb-Zn mine is not compromised.

DOI 10.1016/j.scitotenv.2015.10.143
Citations Scopus - 43Web of Science - 34
Co-authors Yanju Liu, Mahmud Rahman
2016 Venkateswarlu K, Nirola R, Kuppusamy S, Thavamani P, Naidu R, Megharaj M, 'Abandoned metalliferous mines: ecological impacts and potential approaches for reclamation', Reviews in Environmental Science and Biotechnology, 15 327-354 (2016) [C1]

The lack of awareness for timely management of the environment surrounding a metal mine site results in several adverse consequences such as rampant business losses, abandoning th... [more]

The lack of awareness for timely management of the environment surrounding a metal mine site results in several adverse consequences such as rampant business losses, abandoning the bread-earning mining industry, domestic instability and rise in ghost towns, increased environmental pollution, and indirect long-term impacts on the ecosystem. Although several abandoned mine lands (AMLs) exist globally, information on these derelict mines has not been consolidated in the literature. We present here the state-of-the-art on AMLs in major mining countries with emphasis on their impact towards soil health and biodiversity, remediation methods, and laws governing management of mined sites. While reclamation of metalliferous mines by phytoremediation is still a suitable option, there exist several limitations for its implementation. However, many issues of phytoremediation at the derelict mines can be resolved following phytostabilization, a technology that is effective also at the modern operational mine sites. The use of transgenic plant species in phytoremediation of metals in contaminated sites is also gaining momentum. In any case, monitoring and efficacy testing for bioremediation of mined sites is essential. The approaches for reclamation of metalliferous mines such as environmental awareness, effective planning and assessment of pre- and post-mining activities, implementation of regulations, and a safe and good use of phytostabilizers among the native plants for revegetation and ecological restoration are discussed in detail in the present review. We also suggest the use of microbially-enhanced phytoremediation and nanotechnology for efficient reclamation of AMLs, and identify future work warranted in this area of research. Further, we believe that the integration of science of remediation with mining policies and regulations is a reliable option which when executed can virtually balance economic development and environmental destruction for safer future.

DOI 10.1007/s11157-016-9398-6
Citations Scopus - 98Web of Science - 68
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Bahar MM, Megharaj M, Naidu R, 'Oxidation of arsenite to arsenate in growth medium and groundwater using a novel arsenite-oxidizing diazotrophic bacterium isolated from soil', International Biodeterioration and Biodegradation, 106 178-182 (2016) [C1]

An arsenic hyper-tolerant diazotrophic bacterium was isolated from a heavy metal contaminated soil. The pure isolate MM-17 was identified as Azospirillum sp. based on phylogenetic... [more]

An arsenic hyper-tolerant diazotrophic bacterium was isolated from a heavy metal contaminated soil. The pure isolate MM-17 was identified as Azospirillum sp. based on phylogenetic analysis of 16S rRNA. The strain oxidized 100 µM As(III) to As(V) in both culture media (minimal salts) and real groundwater within 8 and 10 h, respectively. The oxidation of As(III) by this strain was observed within the pH range 5-10 with the best performance at pH 7-8. As(III) oxidation was found to be independent of cell growth which implies the oxidation enzymes are constitutively expressed. The whole cell kinetic study highlighted a lower value of kinetic constant, Ks as 32.9 µM As(III), which indicates that the strain MM-17 has greater affinity for As(III). The gene sequence of the large subunit of arsenite oxidase of MM-17 showed 99 and 72% similarity to the large subunit of arsenite oxidase of Stenotrophomonas sp. MM-7 and Sinorhizobium sp. M14, respectively. Sphaeroplasts experiments suggest that arsenite oxidase is a membrane associated protein in MM-17.

DOI 10.1016/j.ibiod.2015.10.019
Citations Scopus - 33Web of Science - 27
Co-authors Mezbaul Bahar, Megh Mallavarapu
2016 Rusmin R, Sarkar B, Biswas B, Churchman J, Liu Y, Naidu R, 'Structural, electrokinetic and surface properties of activated palygorskite for environmental application', Applied Clay Science, 134 95-102 (2016) [C1]

Unlike smectite, the surface characteristics of palygorskite remain underexplored for its potential application in environmental remediation. In this study, palygorskite from West... [more]

Unlike smectite, the surface characteristics of palygorskite remain underexplored for its potential application in environmental remediation. In this study, palygorskite from Western Australia was activated through thermal (300 °C for 4 h), acid (4 M HCl for 2 h at 70 °C) and acid-thermal (acid treatment followed by heating at 300 °C for 4 h) treatments, and the structural and physico-chemical characteristics were examined against the raw clay mineral. The influence of activation was systematically investigated using X-ray Diffraction (XRD), Fourier Transform Infra-Red (FTIR) spectroscopy, N2 adsorption-desorption measurements and solid state 27Al Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) spectroscopy. The XRD patterns indicated preservation of the crystalline structure of palygorskite following all the treatments. These findings were supported by the Al (IV) and Al (VI) coordination peaks (chemical shift ~ 55 and 2.9 ppm, respectively) which were unaltered in the 27Al MAS NMR spectra of the samples. The acid-thermal activated palygorskite exhibited the highest specific surface area (152.7 m2 g- 1) and pore volume (0.2137 cm3 g- 1) which respectively were 3-fold and 69% greater than the raw palygorskite. The potentiometric titration analyses highlighted the possible role of Al derivatives towards development of the surface charge of the activated palygorskites. Electrokinetic studies described the stability of the activated products (zeta potential values ranging from - 5 mV to - 32 mV) at different electrolyte (NaNO3) concentrations. Combined acid-thermal activated palygorskite displayed a stronger specific adsorption of multivalent cations, and held a direct relevance to environmental remediation. Findings of this study will assist in the development of palygorskite-based adsorbents for heavy metal contaminants remediation.

DOI 10.1016/j.clay.2016.07.012
Citations Scopus - 72Web of Science - 54
Co-authors Bhaba Biswas, Yanju Liu
2016 Lamb DT, Kader M, Wang L, Choppala G, Rahman MM, Megharaj M, Naidu R, 'Pore-Water Carbonate and Phosphate As Predictors of Arsenate Toxicity in Soil', ENVIRONMENTAL SCIENCE & TECHNOLOGY, 50 13062-13069 (2016) [C1]
DOI 10.1021/acs.est.6b03195
Citations Scopus - 15Web of Science - 14
Co-authors Liang Wang, Girish Choppala, Megh Mallavarapu, Mahmud Rahman
2016 Perelomov L, Sarkar B, Rahman MM, Goryacheva A, Naidu R, 'Uptake of lead by Na-exchanged and Al-pillared bentonite in the presence of organic acids with different functional groups', Applied Clay Science, 119 417-423 (2016) [C1]

This study investigated the uptake of lead (Pb) ions by Na-rich bentonite (Na-bentonite) and Al-pillared bentonite (Al-bentonite) in the presence or absence of organic acids conta... [more]

This study investigated the uptake of lead (Pb) ions by Na-rich bentonite (Na-bentonite) and Al-pillared bentonite (Al-bentonite) in the presence or absence of organic acids containing different functional groups. Na-bentonite was an effective adsorbent for Pb2+ ions. The element was taken up by the mineral through ion exchange mechanism; and the formation of a lead carbonate hydroxide (hydrocerussite) also occurred. Al-bentonite adsorbed a smaller amount of Pb than Na-bentonite. XRD data indicated that the totality of clay interlayers was occupied by the pillaring agent that led to decrease in Pb uptake. The amount of Pb taken up by Na-bentonite decreased with increasing concentration of citric acid both when Pb and organic acid were added together as a mixture, and when citric acid was added 2 h before the metal ions. Possible reasons for this were the formation of Pb-citrate complexes which had less affinity to Na-bentonite, and also hydrocerussite dissolution at acidic pH. Citric acid, however, did not change Pb uptake by Al-bentonite. Addition of lysine together with Pb did not have any effect on Pb uptake by Na-bentonite and Al-bentonite, which indicated occupation of different adsorption sites by Pb and lysine compared to citrate. However, lysine addition at 1:1 ratio 2 h before Pb decreased the metal uptake, which again may be explained by the effect of lysine in hydrocerussite dissolution. Uptake of Pb in the presence of lysine was also higher when using Na-bentonite compared to Al-bentonite.

DOI 10.1016/j.clay.2015.11.004
Citations Scopus - 35Web of Science - 29
Co-authors Mahmud Rahman
2016 Bekele DN, Naidu R, Chadalavada S, 'Influence of soil properties on vapor-phase sorption of trichloroethylene', Journal of Hazardous Materials, 306 34-40 (2016) [C1]

Current practices in health risk assessment from vapor intrusion (VI) using mathematical models are based on assumptions that the subsurface sorption equilibrium is attained. The ... [more]

Current practices in health risk assessment from vapor intrusion (VI) using mathematical models are based on assumptions that the subsurface sorption equilibrium is attained. The time required for sorption to reach near-steady-state conditions at sites may take months or years to achieve. This study investigated the vapor phase attenuation of trichloroethylene (TCE) in five soils varying widely in clay and organic matter content using repacked columns. The primary indicators of TCE sorption were vapor retardation rate (Rt), the time required for the TCE vapor to pass through the soil column, and specific volume of retention (VR), and total volume of TCE retained in soil. Results show TCE vapor retardation is mainly due to the rapid partitioning of the compound to SOM. However, the specific volume of retention of clayey soils with secondary mineral particles was higher. Linear regression analyses of the SOM and clay fraction with VR show that a unit increase in clay fraction results in higher sorption of TCE (VR) than the SOM. However, partitioning of TCE vapor was not consistent with the samples' surface areas but was mainly a function of the type of secondary minerals present in soils.

DOI 10.1016/j.jhazmat.2015.12.002
Citations Scopus - 14Web of Science - 11
Co-authors Sreenivasulu Chadalavada, Dawit Bekele
2016 Weng X, Jin X, Lin J, Naidu R, Chen Z, 'Removal of mixed contaminants Cr(VI) and Cu(II) by green synthesized iron based nanoparticles', Ecological Engineering, 97 32-39 (2016) [C1]

In this study, iron based nanoparticles (Fe NPs) synthesized by eucalyptus leaf extracts was used to remove mixed Cr(VI) and Cu(II), where the efficiency was 58.9% and 33.0%, resp... [more]

In this study, iron based nanoparticles (Fe NPs) synthesized by eucalyptus leaf extracts was used to remove mixed Cr(VI) and Cu(II), where the efficiency was 58.9% and 33.0%, respectively. In contrast, only 20.2% of Cr(VI) and 11.8% of Cu(II) were removed by adsorption using eucalyptus leaf extracts. In addition, the removal mechanism for mixed Cr(VI) and Cu(II) based on both adsorption and reduction by Fe NPs was confirmed by various characterization techniques, including the formations of Fe NPs, iron oxides and capping layer. Furthermore, the kinetics suggested that firstly, their sorption followed the pseudo second-order model well; and secondly, reduction of Cr(VI) and Cu(II) followed the pseudo-first-order model well. Finally, Fe NPs not only removed Cr(VI) and Cu(II), but also Pb(II) and Zn(II) in electroplating wastewater. This provides a new insights into the removal of metal ions using green Fe NPs with a low cost and environmentally friendly remediation strategy.

DOI 10.1016/j.ecoleng.2016.08.003
Citations Scopus - 86Web of Science - 60
2016 Nuruzzaman M, Rahman MM, Liu Y, Naidu R, 'Nanoencapsulation, Nano-guard for Pesticides: A New Window for Safe Application', JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 64 1447-1483 (2016) [C1]
DOI 10.1021/acs.jafc.5b05214
Citations Scopus - 582Web of Science - 357
Co-authors Mahmud Rahman, Md Nuruzzaman, Yanju Liu
2016 Kuppusamy S, Thavamani P, Megharaj M, Naidu R, 'Bioaugmentation with Novel Microbial Formula vs. Natural Attenuation of a Long-Term Mixed Contaminated Soil - Treatability Studies in Solid- and Slurry-Phase Microcosms', Water, Air, and Soil Pollution, 227 (2016) [C1]

Treatability studies in real contaminated soils are essential to predict the feasibility of microbial consortium augmentation for field-scale bioremediation of contaminated sites.... [more]

Treatability studies in real contaminated soils are essential to predict the feasibility of microbial consortium augmentation for field-scale bioremediation of contaminated sites. In this study, the biodegradation of a mixture of seven PAHs in a manufactured gas plant (MGP) soil contaminated with 3967 mg kg-1 of total PAHs using novel acid-, metal-tolerant, N-fixing, P-solubilizing, and biosurfactant-producing LMW and HMW PAH-degrading bacterial combinations as inoculums was compared in slurry- and solid-phase microcosms over natural attenuation. Bioaugmentation of 5 % of bacterial consortia A and N in slurry- and solid-phase systems enhanced 4.6-5.7 and 9.3-10.7 % of total PAH degradation, respectively, over natural attenuation. Occurrence of 62.7-88 % of PAH biodegradation during natural attenuation in soil and slurry illustrated the accelerated rate of intrinsic metabolic activity of the autochthonous microbial community in the selected MGP soil. Monitoring of the total microbial activity and population of PAH degraders revealed that the observed biodegradation trend in MGP soil resulted from microbial mineralization. In the slurry, higher biodegradation rate constant (k) and lower half-life values (t 1/2) was observed during bioaugmentation with consortium N, highlighting the use of bioaugmentation in bioslurries/bioreactor to achieve rapid and efficient bioremediation compared to that of a static solid system. In general, natural attenuation was on par with bioaugmentation. Hence, depending on the type of soil, natural attenuation might outweigh bioaugmentation and a careful investigation using laboratory treatability studies are highly recommended before the upscale of a developed bioremediation strategy to field level.

DOI 10.1007/s11270-015-2709-7
Citations Scopus - 35Web of Science - 19
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Luo F, Yang D, Chen Z, Megharaj M, Naidu R, 'One-step green synthesis of bimetallic Fe/Pd nanoparticles used to degrade Orange II', Journal of Hazardous Materials, 303 145-153 (2016) [C1]

To reduce cost and enhance reactivity, bimetallic Fe/Pd nanoparticles (NPs) were firstly synthesized using grape leaf aqueous extract to remove Orange II. Green synthesized bimeta... [more]

To reduce cost and enhance reactivity, bimetallic Fe/Pd nanoparticles (NPs) were firstly synthesized using grape leaf aqueous extract to remove Orange II. Green synthesized bimetallic Fe/Pd NPs (98.0%) demonstrated a far higher ability to remove Orange II in 12h compared to Fe NPs (16.0%). Meanwhile, all precursors, e.g., grape leaf extract, Fe2+ and Pd2+, had no obvious effect on removing Orange II since less than 2.0% was removed. Kinetics study revealed that the removal rate fitted well to the pseudo-first-order reduction and pseudo-second-order adsorption model, meaning that removing Orange II via Fe/Pd NPs involved both adsorption and catalytic reduction. The remarkable stability of Fe/Pd NPs showed the potential application for removing azo dyes. Furthermore, Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the changes in Fe/Pd NPs before and after reaction with Orange II. High Performance Liquid Chromatography-Mass Spectrum (HPLC-MS) identified the degraded products in the removal of Orange II, and finally a removal mechanism was proposed. This one-step strategy using grape leaf aqueous extract to synthesize Fe/Pd NPs is simple, cost-effective and environmentally benign, making possible the large-scale production of Fe/Pd NPs for field remediation.

DOI 10.1016/j.jhazmat.2015.10.034
Citations Scopus - 132Web of Science - 96
Co-authors Megh Mallavarapu
2016 Abbasian F, Lockington R, Megharaj M, Naidu R, 'A Review on the Genetics of Aliphatic and Aromatic Hydrocarbon Degradation', APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY, 178 224-250 (2016) [C1]
DOI 10.1007/s12010-015-1881-y
Citations Scopus - 57Web of Science - 56
Co-authors Megh Mallavarapu
2016 Kuppusamy S, Thavamani P, Megharaj M, Nirola R, Lee YB, Naidu R, 'Assessment of antioxidant activity, minerals, phenols and flavonoid contents of common plant/tree waste extracts', INDUSTRIAL CROPS AND PRODUCTS, 83 630-634 (2016) [C1]
DOI 10.1016/j.indcrop.2015.12.060
Citations Scopus - 26Web of Science - 17
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Wong M-H, Ok Y-S, Naidu R, 'Biological-waste as resource, with a focus on food waste PREFACE', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 23 7071-7073 (2016)
DOI 10.1007/s11356-016-6078-6
Citations Scopus - 4Web of Science - 2
2016 Gao Y, Wang F, Wu Y, Naidu R, Chen Z, 'Comparison of degradation mechanisms of microcystin-LR using nanoscale zero-valent iron (nZVI) and bimetallic Fe/Ni and Fe/Pd nanoparticles', Chemical Engineering Journal, 285 459-466 (2016) [C1]

Microcystin-LR (MC-LR) as a drinking water contaminant was degraded using iron-based nanoparticles such as nZVI, Fe/Ni and Fe/Pd. Batch experiments showed that 28.0% of MC-LR with... [more]

Microcystin-LR (MC-LR) as a drinking water contaminant was degraded using iron-based nanoparticles such as nZVI, Fe/Ni and Fe/Pd. Batch experiments showed that 28.0% of MC-LR with the initial concentration of 5mgL-1 was removed using nZVI, while more than 90% of MC-LR was removed using either bimetallic Fe/Ni or Fe/Pd after degrading for 120min. In addition, the results indicated that Fe0 was oxided to iron oxide or hydroxide after reacting with MC-LR, while Ni or Pd acted as the catalysis to prevent Fe0 corrosion and generating hydrogen via water reduction. Degradation of MC-LR by iron-based nanoparticles fitted well to the pseudo-first order kinetic model and the degradation was a diffusion-controlled reaction with low activation energies (8-21kJmol-1). Finally, the degradation mechanisms of MC-LR using iron-based nanoparticles were proposed according to the LC-MS analysis. In nZVI case, when the MC-LR was quickly adsorbed on nanoparticles, electron transfer and H2 generated from iron corrosion were generated and broke down the Adda composition of MC-LR. Based on corrosion in the Fe0-H2O system, bimetallic Fe/Ni and Fe/Pd further utilized the abundant hydrogen radical decomposed from H2 under the catalysis of Ni or Pd, and destroyed the Adda to form small molecules.

DOI 10.1016/j.cej.2015.09.078
Citations Scopus - 69Web of Science - 60
2016 Fang C, Megharaj M, Naidu R, 'Surface-enhanced Raman scattering (SERS) detection of fluorosurfactants in firefighting foams', RSC Advances, 6 11140-11145 (2016) [C1]

We demonstrated SERS (surface-enhanced Raman scattering) detection of fluorosurfactants (FSs), which are commonly formulated in aqueous firefighting foams (AFFFs), by increasing t... [more]

We demonstrated SERS (surface-enhanced Raman scattering) detection of fluorosurfactants (FSs), which are commonly formulated in aqueous firefighting foams (AFFFs), by increasing their loading affinity and boosting their Raman activity. In order to increase FS's loading affinity, we introduced a cationic dye (ethyl violet or methyl blue) into the aqueous incubation solution to co-precipitate the FS onto the SERS substrate surface by forming an immiscible ion-pair (dye-FS). In the meantime, the Raman signal intensity was boosted due to the much higher Raman activity of the dye than that of FS. We compared two kinds of SERS substrate, patterned silver (Ag) surface and graphene oxide (GO) membrane, and noted the former (dye-FS-Ag) enhanced the Raman signal whilst the latter (dye-FS-GO) increased the loading affinity of the ion-pair due to the hydrophobic surface. We thus introduced silver nanoparticles (AgNPs) into the incubation solution (as well as dye) to co-precipitate FS onto the GO surface via an assembly of dye-FS-AgNP-GO. Using this assembly, we successfully detected FSs including pentadecafluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and 1H,1H,2H,2H-perfluorooctanesulfonic acid (6:2FTS), with a limit-of-detection (LOD) of ~50 ppb (~120 nM) for PFOA.

DOI 10.1039/c5ra26114g
Citations Scopus - 38Web of Science - 28
Co-authors Megh Mallavarapu, Cheng Fang
2016 Ramadass K, Palanisami T, Smith E, Mayilswami S, Megharaj M, Naidu R, 'Earthworm Comet Assay for Assessing the Risk of Weathered Petroleum Hydrocarbon Contaminated Soils: Need to Look Further than Target Contaminants', Archives of Environmental Contamination and Toxicology, 71 561-571 (2016) [C1]
DOI 10.1007/s00244-016-0318-0
Citations Scopus - 17Web of Science - 14
Co-authors Kavitha Ramadass, Thava Palanisami, Megh Mallavarapu
2016 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Sensitivity and Antioxidant Response of Chlorella sp. MM3 to Used Engine Oil and Its Water Accommodated Fraction', Bulletin of Environmental Contamination and Toxicology, 97 71-77 (2016) [C1]

We exposed the microalgal strain, Chlorella sp. MM3, to unused or used engine oil, or their water accommodated fractions (WAFs) to determine growth inhibition and response of anti... [more]

We exposed the microalgal strain, Chlorella sp. MM3, to unused or used engine oil, or their water accommodated fractions (WAFs) to determine growth inhibition and response of antioxidant enzymes. Oil type and oil concentration greatly affected the microalgal growth. Used oil at 0.04¿% (0.4¿g L-1) resulted in 50¿% inhibition in algal growth, measured in terms of chlorophyll-a, while the corresponding concentration of unused oil was nontoxic. Similarly, used oil WAF showed significant toxicity to the algal growth at 10¿% level, whereas WAF from unused oil was nontoxic even at 100¿% concentration. Peroxidase enzyme in the microalga significantly increased with used oil at concentrations above 0.04¿g L-1 whereas the induction of superoxide dismutase and catalase was apparent only at 0.06¿g L-1. Activities of the antioxidant enzymes increased significantly when the microalga was exposed to 75 and 100¿% WAF obtained from used oil. The used oil toxicity on microalga could be due to the presence of toxic soluble mono- and polyaromatic compounds, heavy metals, and other compounds attained by the oil during its use in the motor engines.

DOI 10.1007/s00128-016-1817-4
Citations Scopus - 14Web of Science - 11
Co-authors Megh Mallavarapu, Kavitha Ramadass
2016 Ma C, Ming H, Lin C, Naidu R, Bolan N, 'Phytoextraction of heavy metal from tailing waste using Napier grass', CATENA, 136 74-83 (2016) [C1]
DOI 10.1016/j.catena.2015.08.001
Citations Scopus - 27Web of Science - 20
Co-authors Nanthi Bolan
2016 Subramaniyam V, Subashchandrabose SR, Ganeshkumar V, Thavamani P, Chen Z, Naidu R, Megharaj M, 'Cultivation of Chlorella on brewery wastewater and nano-particle biosynthesis by its biomass', BIORESOURCE TECHNOLOGY, 211 698-703 (2016) [C1]
DOI 10.1016/j.biortech.2016.03.154
Citations Scopus - 61Web of Science - 46
Co-authors Suresh Subashchandrabose, Thava Palanisami, Megh Mallavarapu
2016 Liu Y, Naidu R, Ming H, Dharmarajan R, Du J, 'Effects of thermal treatments on the characterisation and utilisation of red mud with sawdust additive', Waste Management and Research, 34 518-526 (2016) [C1]
DOI 10.1177/0734242X16634197
Citations Scopus - 9Web of Science - 9
Co-authors Yanju Liu
2016 Zhu C, Dong X, Chen Z, Naidu R, 'Adsorption of aqueous Pb(II), Cu(II), Zn(II) ions by amorphous tin(VI) hydrogen phosphate: an excellent inorganic adsorbent', International Journal of Environmental Science and Technology, 13 1257-1268 (2016) [C1]

Amorphous tin(VI) hydrogen phosphate (ATHP) was synthesized using the liquid phase precipitation method and served as an adsorbent to remove Pb(II), Cu(II), and Zn(II) from aqueou... [more]

Amorphous tin(VI) hydrogen phosphate (ATHP) was synthesized using the liquid phase precipitation method and served as an adsorbent to remove Pb(II), Cu(II), and Zn(II) from aqueous solutions. The ATHP was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption¿desorption techniques. Adsorption properties were evaluated as a function of pH, reaction time, concentration of reactants, and salinity. Their equilibrium adsorption data were modeled using Freundlich, Langmuir, and Dubinin¿Kaganer¿Radushkevich isotherms, respectively. The results revealed that adsorption equilibrium reached within 180¿min. ATHP indicated good adsorption even below the pHZPC, and best adsorption at pH 5 for Pb(II) and Cu(II) and at pH 5.5 for Zn(II) was observed. Equilibrium data fitted better to the Langmuir model for Pb(II) and Cu(II) and fitted better to the Freundlich model for Zn(II). The saturated adsorption capacities deduced from the Langmuir model were 2.425, 1.801, and 0.600¿mmol/g for Cu(II), Pb(II), and Zn(II), respectively, indicating an adsorption affinity order of Cu¿>¿Pb¿>¿Zn. There is a negative correlation between the concentration of NaCl and adsorption capacity of ATHP, yet ATHP still exhibited excellent adsorption having an adsorption capacity of 19.35, 15.16, 6.425¿mg/g when the concentration of NaCl was 0.6¿mol/L. The free energy (E) was 12.33, 10.70, and 14.74¿kJ/mol for Pb(II), Cu(II), and Zn(II), respectively. An adsorption mechanism based on ion exchange between heavy metal ions and H+ in the ATHP is proposed. Furthermore, the used ATHP was regenerated by HCl solution and the adsorbent was used repeatedly.

DOI 10.1007/s13762-016-0964-9
Citations Scopus - 29Web of Science - 23
2016 Panneerselvan L, Sivaram AK, Mallavarapu M, Naidu R, 'Evaluation of cyto- and genotoxic effects of Class B firefighting foam products: Tridol-S 3% AFFF and Tridol-S 6% AFFF to Allium cepa', Environmental Technology and Innovation, 6 185-194 (2016) [C1]

Worldwide a multitude of firefighting compounds are currently used for the mitigation and protection of man-made structures and forests alike from fire damages. Among the class of... [more]

Worldwide a multitude of firefighting compounds are currently used for the mitigation and protection of man-made structures and forests alike from fire damages. Among the class of firefighting agents, Class B firefighting foams are generally used to control fires generated from hydrocarbon liquids. In the present study, we assessed the cyto- and genotoxicity of two widely used class B firefighting foam concentrates, Tridol-S 3% and Tridol-S 6% to Alliumcepa through chromosomal aberration and comet assay using root meristem cells. A. cepa root tips were exposed to Tridol-S 3% and Tridol-S 6% with six different concentrations (0%, 0.005%, 0.01%, 0.02%, 0.03%, 0.04% and 0.05%) for 24 h. Cytogenetic effect endpoints such as mitotic index, and chromosomal aberrations were observed. Chromosomal aberrations in the control (untreated onion root tips) was negligible with the mitotic index (MI) value of 79.6%, while the MI significantly decreased in all the test concentrations of firefighting compounds. Genotoxicity assessment through comet assay also revealed that both the products were genotoxic with a significant increase in per cent tail DNA and olive tail moment. Among the test compounds, Tridol-S 3% was more toxic than Tridol-S 6%. To our knowledge, this is the first study on the cyto- and genotoxic effects of class B firefighting foams to A. cepa root meristem cells. This study also suggests that the toxicological studies using A. cepa root meristem cells can be employed for evaluating the toxicological impacts of firefighting foams in the environment.

DOI 10.1016/j.eti.2016.10.003
Citations Scopus - 9Web of Science - 6
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2016 Faustorilla MV, Chen Z, Dharmarajan R, Naidu R, 'Solid phase extraction and fractionation of total petroleum hydrocarbons in contaminated soil by GC-MSD/FID techniques', Journal of Chromatography and Separation Techniques, 7 87-87 (2016)
DOI 10.4172/2157-7064.C1.020
2016 Mahbub KR, Krishnan K, Naidu R, Megharaj M, 'Mercury resistance and volatilization by Pseudoxanthomonas sp. SE1 isolated from soil', Environmental Technology and Innovation, 6 94-104 (2016) [C1]

A mercury resistant bacterial strain SE1 isolated from contaminated soil was identified as Pseudoxanthomonas based on 16s rRNA sequencing. The Hg resistance was examined in both n... [more]

A mercury resistant bacterial strain SE1 isolated from contaminated soil was identified as Pseudoxanthomonas based on 16s rRNA sequencing. The Hg resistance was examined in both nutrient-rich media as well as low nutrient media and expressed as EC50 and MIC values. Estimated EC50 and MIC values in nutrient-rich media and low nutrient media had the following respective recordings ¿ 22.6 mg L-1; 23.1 mg L-1 and 1.4 mg L-1 and 1.7 mg L-1. The isolate was able to volatilize inorganic mercury demonstrated by a modified photographic film experiment and subsequently revealed its ability to remove mercury from the solution. The ICP-QQQ-MS analysis of SE1 inoculated solution showed almost 60% of 1.5 mg L-1 mercury was volatilized in 6 h and almost 40% were accumulated in cell pellets. The mercuric reductase gene merA was identified in the genome of isolate SE1 and sequenced. The deduced amino acid sequence of merA gene indicated a sequence homology with different organisms from the alpha proteobacteria group and eukaryotic fungi. merA encoded enzyme mercuric reductase activity was evident in the crude protein of the isolate. The isolate's ability to resist Hg, it's Hg volatilization potential and the presence of merA gene and mercuric reductase enzyme demonstrates the potential application of this strain in mercury bioremediation.

DOI 10.1016/j.eti.2016.08.001
Citations Scopus - 43Web of Science - 30
Co-authors Megh Mallavarapu
2016 Kuppusamy S, Thavamani P, Megharaj M, Lee YB, Naidu R, 'Isolation and characterization of polycyclic aromatic hydrocarbons (PAHs) degrading, pH tolerant, N-fixing and P-solubilizing novel bacteria from manufactured gas plant (MGP) site soils', Environmental Technology and Innovation, 6 204-219 (2016) [C1]

Dearth of high molecular weight contaminant degradation, pH tolerance and growth limiting nutrient assimilation potentials of the selected microorganisms are some of the prime fac... [more]

Dearth of high molecular weight contaminant degradation, pH tolerance and growth limiting nutrient assimilation potentials of the selected microorganisms are some of the prime factors reasonable for the failures in field-scale bioremediation of PAHs contaminated soils. Hence an effort was made in this study for the first time to identify HMW PAHs degrading, N-fixing and P-solubilizing bacteria with pH tolerance from long-term manufactured gas plant site soils. Four distinct strains that could degrade both LMW and HMW PAHs were identified. Among the isolates, Stenotrophomonas (MTS-2) followed by Citrobacter (MTS-3) and Pseudomonas (MTS-1) were furthermost effective in the degradation of HMW PAHs either as individual or in the presence of co-substrate (LMW PAHs). MTS-1, 2 and 3 (co)degraded model LMW PAHs, Phe (100% of 150 mg L-1) and HMW PAHs Pyr (100% of 150 mg L-1) or BaP (90¿100% of 50 mg L-1) in 3, 12¿15 and 30 days, respectively and recorded the least half-life time (t1/2) and highest biodegradation rate constants (k). One of the significant findings is the diazotrophic P-solubilization ability, acid and alkali tolerance (optimum pH=5.0¿8.0) of the HMW PAHs degrading Pseudomonas strain MTS-1. Stenotrophomonas (MTS-2) was also found to be superior as it could solubilize P and tolerate acidic condition (optimum pH=5.0¿7.5) during HMW PAHs degradation. Further, our study is the first evidence of diazotrophic P solubilization potential of Agrobacterium (MTS-4) and P-solubilizing capacity of Citrobacter (MTS-3) during bioremediation. Thus, the results of this study demonstrate the promising use of the newly identified PAH degraders, notably MTS-1, 2 and 3 either as individuals or as consortia as an excellent candidate in the bioremediation or phytoremediation of PAHs contaminated soils.

DOI 10.1016/j.eti.2016.04.006
Citations Scopus - 27Web of Science - 17
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Yan K, Dong Z, Liu Y, Naidu R, 'Quantifying statistical relationships between commonly used in vitro models for estimating lead bioaccessibility', Environmental Science and Pollution Research, 23 6873-6882 (2016) [C1]

Bioaccessibility to assess potential risks resulting from exposure to Pb-contaminated soils is commonly estimated using various in vitro methods. However, existing in vitro method... [more]

Bioaccessibility to assess potential risks resulting from exposure to Pb-contaminated soils is commonly estimated using various in vitro methods. However, existing in vitro methods yield different results depending on the composition of the extractant as well as the contaminated soils. For this reason, the relationships between the five commonly used in vitro methods, the Relative Bioavailability Leaching Procedure (RBALP), the unified BioAccessibility Research Group Europe (BARGE) method (UBM), the Solubility Bioaccessibility Research Consortium assay (SBRC), a Physiologically Based Extraction Test (PBET), and the in vitro Digestion Model (RIVM) were quantified statistically using 10 soils from long-term Pb-contaminated mining and smelter sites located in Western Australia and South Australia. For all 10 soils, the measured Pb bioaccessibility regarding all in vitro methods varied from 1.9 to 106¿% for gastric phase, which is higher than that for intestinal phase: 0.2 ~ 78.6¿%. The variations in Pb bioaccessibility depend on the in vitro models being used, suggesting that the method chosen for bioaccessibility assessment must be validated against in vivo studies prior to use for predicting risk. Regression studies between RBALP and SRBC, RBALP and RIVM (0.06) (0.06¿g of soil in each tube, S:L ratios for gastric phase and intestinal phase are 1:375 and 1:958, respectively) showed that Pb bioaccessibility based on the three methods were comparable. Meanwhile, the slopes between RBALP and UBM, RBALP and RIVM (0.6) (0.6¿g soil in each tube, S:L ratios for gastric phase and intestinal phase are 1:37.5 and 1:96, respectively) were 1.21 and 1.02, respectively. The findings presented in this study could help standardize in vitro bioaccessibility measurements and provide a scientific basis for further relating Pb bioavailability and soil properties.

DOI 10.1007/s11356-015-5947-8
Citations Scopus - 17Web of Science - 11
Co-authors Yanju Liu
2016 Seshadri B, Bolan NS, Wijesekara H, Kunhikrishnan A, Thangarajan R, Qi F, et al., 'Phosphorus-cadmium interactions in paddy soils', Geoderma, 270 43-59 (2016) [C1]

Regular application of phosphate (P) fertilisers has been identified as the main source of heavy metal(loid) contamination including cadmium (Cd) in agricultural soils. Some of th... [more]

Regular application of phosphate (P) fertilisers has been identified as the main source of heavy metal(loid) contamination including cadmium (Cd) in agricultural soils. Some of these P fertilisers that act as a source of Cd contamination of soils have also been found to act as a sink for the immobilisation of this metal(loid). In paddy soils, redox reactions play an important role in the (im)mobilisation of nutrients and heavy metal(loid)s, as a result of flooding of the rice plains. Although a number of studies have examined the potential value of P compounds in the immobilisation of metals in contaminated soils, there has been no comprehensive review on the mechanisms involved in the P-induced (im)mobilisation of Cd in paddy soils. There are a number of factors that influences P induced Cd (im)mobilisation in paddy soils that include pH, redox reactions, liming effect, rhizosphere acidification and root iron plaques. Following a brief overview of the reactions of Cd and common P compounds that are used as fertiliser in soils, the review focuses on the above mentioned mechanisms for the (im)mobilisation of Cd by P compounds in paddy soils. The role of iron plaques on Cd status in soil and rice plants is also discussed followed by a summary and future research needs.

DOI 10.1016/j.geoderma.2015.11.029
Citations Scopus - 90Web of Science - 60
Co-authors Nanthi Bolan
2016 Cheng Q, Hu Z, Naidu R, Xiao B, 'The performance and validation of an underground river reactor using compost energy as heat source', Ecological Engineering, 87 98-101 (2016)
DOI 10.1016/j.ecoleng.2015.11.038
Citations Scopus - 4Web of Science - 4
2016 Liu C, Subashchandrabose S, Ming H, Xiao B, Naidu R, Megharaj M, 'Phycoremediation of dairy and winery wastewater using Diplosphaera sp. MM1', Journal of Applied Phycology, 28 3331-3341 (2016) [C1]

A new green microalgal species was isolated, identified and investigated for its biomass production and nutrient removal efficiency in dairy and winery wastewater in this study. T... [more]

A new green microalgal species was isolated, identified and investigated for its biomass production and nutrient removal efficiency in dairy and winery wastewater in this study. The 18S rRNA-based phylogenetic analysis revealed that this new strain is a Diplosphaera sp. and was designated strain MM1. The growth of this strain was evaluated in different diluted dairy and winery wastewaters. The highest algal biomass production (up to 2.3¿g¿L-1) was obtained in dairy wastewater (D3; dairy wastewater 1:2 deionised water) after 14¿days of culture. However, for winery wastewater, the highest algal biomass production (up to 1.46¿g¿L-1) was obtained in wastewater combination W2 (winery wastewater 1:1 deionised water) after 14¿days of culture. Turbid dairy wastewater with high concentration of nitrogen and phosphorous slowed down the initial growth of the alga. However, at the end of day 14, biomass production was nearly twofold higher than that of winery wastewater. The findings from both types of wastewater suggest that Diplosphaera sp. MM1 has potential for its application in generating biomass with simultaneous remediation of nutrient-rich wastewater.

DOI 10.1007/s10811-016-0894-4
Citations Scopus - 31Web of Science - 20
Co-authors Megh Mallavarapu, Suresh Subashchandrabose
2016 Sanderson P, Naidu R, Bolan N, 'The effect of environmental conditions and soil physicochemistry on phosphate stabilisation of Pb in shooting range soils', Journal of Environmental Management, 170 123-130 (2016) [C1]

The stabilisation of Pb in the soil by phosphate is influenced by environmental conditions and physicochemical properties of the soils to which it is applied. Stabilisation of Pb ... [more]

The stabilisation of Pb in the soil by phosphate is influenced by environmental conditions and physicochemical properties of the soils to which it is applied. Stabilisation of Pb by phosphate was examined in four soils under different environmental conditions.The effect of soil moisture and temperature on stabilisation of Pb by phosphate was examined by measurement of water extractable and bioaccessible Pb, sequential fractionation and X-ray absorption spectroscopy. The addition of humic acid, ammonium nitrate and chloride was also examined for inhibition or improvement of Pb stability with phosphate treatment.The effect of moisture level varied between soils. In soil MB and DA a soil moisture level of 50% water holding capacity was sufficient to maximise stabilisation of Pb, but in soil TV and PE reduction in bioaccessible Pb was inhibited at this moisture level. Providing moisture at twice the soil water holding capacity did not enhance the effect of phosphate on Pb stabilisation. The difference of Pb stability as a result of incubating phosphate treated soils at 18 °C and 37 °C was relatively small. However wet-dry cycles decreased the effectiveness of phosphate treatment. The reduction in bioaccessible Pb obtained was between 20 and 40% with the most optimal treatment conditions. The reduction in water extractable Pb by phosphate was substantial regardless of incubation conditions and the effect of different temperature and soil moisture regimes was not significant.Selective sequential extraction showed phosphate treatment converted Pb in fraction 1 (exchangeable, acid and water soluble) to fraction 2 (reducible). There were small difference in fraction 4 (residual) Pb and fraction 1 as a result of treatment conditions. X-ray absorption spectroscopy of stabilised PE soil revealed small differences in Pb speciation under varying soil moisture and temperature treatments. The addition of humic acid and chloride produced the greatest effect on Pb speciation in phosphate treated soils.

DOI 10.1016/j.jenvman.2016.01.017
Citations Scopus - 27Web of Science - 20
Co-authors Nanthi Bolan
2016 Abbasian F, Lockington R, Megharaj M, Naidu R, 'Identification of a new operon involved in desulfurization of dibenzothiophenes using a metagenomic study and cloning and functional analysis of the genes', Enzyme and Microbial Technology, 87-88 24-28 (2016) [C1]

The presence of sulphur-substituted hydrocarbons in fossil fuels are one of main reasons for the release of sulfur oxides into the environment. Dibenzothiophenes (DBT) are organic... [more]

The presence of sulphur-substituted hydrocarbons in fossil fuels are one of main reasons for the release of sulfur oxides into the environment. Dibenzothiophenes (DBT) are organic sulfur-containing molecules in crude oil, which have the potential for biological oxidation, with the sulphur being removed through an enzymatic cleavage of the C. S bonds. Therefore, finding new strains that can desulfurize this compound has recently become a point of interest. In this study, three new genes involved in the bacterial desulfurization of Dibenzothiophene, which were sequenced in the course of a metagenomic study, were isolated by PCR amplification in the laboratory. The activities of these genes were then analysed following insertion into an expression vector and cloning in Escherichia coli DH5a cells. Based on the results, all three genes were actively expressed and their products could act on their corresponding substrates.

DOI 10.1016/j.enzmictec.2016.02.009
Citations Scopus - 13Web of Science - 10
Co-authors Megh Mallavarapu
2016 Kuppusamy S, Thavamani P, Megharaj M, Venkateswarlu K, Lee YB, Naidu R, 'Potential of Melaleuca diosmifolia leaf as a low-cost adsorbent for hexavalent chromium removal from contaminated water bodies', Process Safety and Environmental Protection, 100 173-182 (2016) [C1]

The present study describes for the first time the utilization of dried twigs of Melaleuca diosmifolia, fallen off from the plant, to detoxify and remove hexavalent chromium or Cr... [more]

The present study describes for the first time the utilization of dried twigs of Melaleuca diosmifolia, fallen off from the plant, to detoxify and remove hexavalent chromium or Cr(VI) from aqueous systems. Initial characterization by gas chromatography revealed that the selected biomaterial is one of the natural sources of eucalyptol. It constituted high concentrations of reducing compounds (iron, phenols and flavonoids). Batch studies revealed that the biosorbent (5 g L-1) was able to remove 97-99.9% of 250 mg L-1 Cr(VI) at wide-ranging pH (2-10) and temperature (24-48 °C). Adsorption kinetics was well described using the pseudo-second-order kinetic model, while the equilibrium adsorption data were interpreted in terms of the Langmuir isotherm model. The monolayer adsorption capacity was 62.5 mg g-1. Both inductively coupled plasma optical emission spectrometry and liquid chromatography analyses of the aqueous and solid phases revealed that the mechanism of Cr(VI) removal was 'adsorption-coupled reduction'. Scanning electron microscope, infrared spectroscopy and X-ray diffraction analyses of the biosorbent before and after adsorption also confirmed that both adsorption and reduction of Cr(VI) to Cr(III) followed by complexation onto functional groups of the active surface contributed to the removal of Cr(VI) from aqueous solution. The selected biomaterial effectively (99.9%) removed Cr(VI) in lake and sea water samples, highlighting its potential for remediating Cr(VI) in real environmental conditions.

DOI 10.1016/j.psep.2016.01.009
Citations Scopus - 73Web of Science - 60
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Biswas B, Sarkar B, Naidu R, 'Influence of thermally modified palygorskite on the viability of polycyclic aromatic hydrocarbon-degrading bacteria', Applied Clay Science, 134 153-160 (2016) [C1]

Thermal activation of palygorskite is considered as a simple and cost-effective method for modifying its structural and surface properties, which can be congenial for the adsorpti... [more]

Thermal activation of palygorskite is considered as a simple and cost-effective method for modifying its structural and surface properties, which can be congenial for the adsorptive removal of environmental contaminants. However, for a more efficient removal of organic contaminants like polycyclic aromatic hydrocarbons (PAH), clay-microbial synergy combining both adsorption and biodegradation is an emerging strategy. In this study, we investigated the compatibility of heat treated palygorskite products (100¿900 °C) with a PAH-degrading soil bacterium Burkholderia sartisoli. The mineralogical and physico-chemical properties were characterised in detail, and the bacterial adhesion to the substrate and their growth were observed in relation to these properties. The major variation in the cation exchange capacity (CEC), surface area, water content and the elemental dissolution in the aqueous medium occurred in the palygorskite products heated at extreme temperature (700¿900 °C). These changes significantly influenced the bacterial growth and attachment. The maximum viability was imparted by the palygorskite product obtained at 400 °C. Dissolution of Al from products heated above 500 °C also posed inhibitory effect on bacterial growth in the aqueous media. This study provided valuable information about the mechanisms of bacterial viability as affected by modified clay minerals, which is important for developing a novel clay-modulated-bioremediation technology.

DOI 10.1016/j.clay.2016.07.003
Citations Scopus - 23Web of Science - 22
Co-authors Bhaba Biswas
2016 Kumar M, Ramanathan AL, Rahman MM, Naidu R, 'Concentrations of inorganic arsenic in groundwater, agricultural soils and subsurface sediments from the middle Gangetic plain of Bihar, India', Science of the Total Environment, 573 1103-1114 (2016) [C1]

Concentrations of inorganic forms [arsenite, As(III) and arsenate, As(V) of arsenic (As) present in groundwater, agricultural soils and subsurface sediments located in the middle ... [more]

Concentrations of inorganic forms [arsenite, As(III) and arsenate, As(V) of arsenic (As) present in groundwater, agricultural soils and subsurface sediments located in the middle Gangetic plain of Bihar, India were determined. Approximately 73% of the groundwater samples (n¿=¿19) show As(III) as the dominant species while 27% reveals As(V) was the dominant species. The concentration of As(III) in agricultural soil samples varies from not detectable to 40¿µg/kg and As(V) was observed as the major species (ranging from 1050 to 6835¿µg/kg) while the total As concentration varied from 3528 to 14,690¿µg/kg. Total extracted concentration of As was higher in the subsurface sediments (range 9119¿20,056¿µg/kg in Methrapur and 4788¿19,681¿µg/kg in Harail Chapar) than the agricultural soil, indicating the subsurface sediment as a source of As. Results of X-ray diffraction (XRD) and environmental scanning electron microscope (ESEM) revealed the presence of hematite and goethite throughout the vertical section below while magnetite was observed only in the upper oxidized layer at Methrapur and Harail Chapar. Alteration of Fe-oxides and presence of fibrous goethite indicating presence of diagenetic sediment. Siderite plays a crucial role as sinks to the As in subsurface sediments. The study also concluded that decomposition of organic matter present in dark and grey sections promote the redox conditions and trigger mobilization of As into groundwater.

DOI 10.1016/j.scitotenv.2016.08.109
Citations Scopus - 48Web of Science - 42
Co-authors Mahmud Rahman
2016 Islam S, Rahman MM, Islam MR, Naidu R, 'Arsenic accumulation in rice: Consequences of rice genotypes and management practices to reduce human health risk', Environment International, 96 139-155 (2016) [C1]

Rice is an essential staple food and feeds over half of the world&apos;s population. Consumption of rice has increased from limited intake in Western countries some 50¿years ago t... [more]

Rice is an essential staple food and feeds over half of the world's population. Consumption of rice has increased from limited intake in Western countries some 50¿years ago to major dietary intake now. Rice consumption represents a major route for inorganic arsenic (As) exposure in many countries, especially for people with a large proportion of rice in their daily diet as much as 60%. Rice plants are more efficient in assimilating As into its grains than other cereal crops and the accumulation may also adversely affect the quality of rice and their nutrition. Rice is generally grown as a lowland crop in flooded soils under reducing conditions. Under these conditions the bioavailability of As is greatly enhanced leading to excessive As bioaccumulation compared to that under oxidizing upland conditions. Inorganic As species are carcinogenic to humans and even at low levels in the diet pose a considerable risk to humans. There is a substantial genetic variation among the rice genotypes in grain-As accumulation as well as speciation. Identifying the extent of genetic variation in grain-As concentration and speciation of As compounds are crucial to determining the rice varieties which accumulate low inorganic As. Varietal selection, irrigation water management, use of fertilizer and soil amendments, cooking practices etc. play a vital role in reducing As exposure from rice grains. In the meantime assessing the bioavailability of As from rice is crucial to understanding human health exposure and reducing the risk.

DOI 10.1016/j.envint.2016.09.006
Citations Scopus - 97Web of Science - 73
Co-authors Mahmud Rahman
2016 Datta B, Durand F, Laforge S, Prakash O, Esfahani HK, Chadalavada S, Naidu R, 'Preliminary Hydrogeologic Modeling and Optimal Monitoring Network Design for a Contaminated Abandoned Mine Site Area: Application of Developed Monitoring Network Design Software', Journal of Water Resource and Protection, 08 46-64 (2016) [C1]
DOI 10.4236/jwarp.2016.81005
Co-authors Sreenivasulu Chadalavada
2016 Abbasi S, Lamb DT, Palanisami T, Kader M, Matanitobua V, Megharaj M, Naidu R, 'Bioaccessibility of barium from barite contaminated soils based on gastric phase in vitro data and plant uptake', Chemosphere, 144 1421-1427 (2016) [C1]

Barite contamination of soil commonly occurs from either barite mining or explorative drilling operations. This work reported in vitro data for barite contaminated soils using the... [more]

Barite contamination of soil commonly occurs from either barite mining or explorative drilling operations. This work reported in vitro data for barite contaminated soils using the physiologically based extraction test (PBET) methodology. The existence of barite in plant tissue and the possibility of 'biomineralised' zones was also investigated using Scanning Electron Microscopy. Soils with low barium (Ba) concentrations showed a higher proportion of Ba extractability than barite rich samples. Barium uptake to spinach from soil was different between short term spiking studies and field weathered soils. Furthermore, Ba crystals were not evident in spinach tissue or acid digest solutions grown in barium nitrate spiked soils despite high accumulation. Barite was found in the plant digest solutions from barite contaminated soils only. Results indicate that under the conservative assumptions made, a child would need to consume extreme quantities of soil over an extended period to cause chronic health problems.

DOI 10.1016/j.chemosphere.2015.10.031
Citations Scopus - 21Web of Science - 19
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Chekli L, Bayatsarmadi B, Sekine R, Sarkar B, Shen AM, Scheckel KG, et al., 'Analytical characterisation of nanoscale zero-valent iron: A methodological review', Analytica Chimica Acta, 903 13-35 (2016) [C1]

Zero-valent iron nanoparticles (nZVI) have been widely tested as they are showing significant promise for environmental remediation. However, many recent studies have demonstrated... [more]

Zero-valent iron nanoparticles (nZVI) have been widely tested as they are showing significant promise for environmental remediation. However, many recent studies have demonstrated that their mobility and reactivity in subsurface environments are significantly affected by their tendency to aggregate. Both the mobility and reactivity of nZVI mainly depends on properties such as particle size, surface chemistry and bulk composition. In order to ensure efficient remediation, it is crucial to accurately assess and understand the implications of these properties before deploying these materials into contaminated environments. Many analytical techniques are now available to determine these parameters and this paper provides a critical review of their usefulness and limitations for nZVI characterisation. These analytical techniques include microscopy and light scattering techniques for the determination of particle size, size distribution and aggregation state, and X-ray techniques for the characterisation of surface chemistry and bulk composition. Example characterisation data derived from commercial nZVI materials is used to further illustrate method strengths and limitations. Finally, some important challenges with respect to the characterisation of nZVI in groundwater samples are discussed.

DOI 10.1016/j.aca.2015.10.040
Citations Scopus - 86Web of Science - 70
2016 Mandal S, Thangarajan R, Bolan NS, Sarkar B, Khan N, Ok YS, Naidu R, 'Biochar-induced concomitant decrease in ammonia volatilization and increase in nitrogen use efficiency by wheat', CHEMOSPHERE, 142 120-127 (2016) [C1]
DOI 10.1016/j.chemosphere.2015.04.086
Citations Scopus - 241Web of Science - 178
Co-authors Nanthi Bolan
2016 Xia Q, Peng C, Lamb D, Mallavarapu M, Naidu R, Ng JC, 'Bioaccessibility of arsenic and cadmium assessed for in vitro bioaccessibility in spiked soils and their interaction during the Unified BARGE Method (UBM) extraction', Chemosphere, 147 444-450 (2016) [C1]

Recent decades have seen a growing popularity of in vitro bioaccessibility being utilised as a screening tool in human health risk assessment. However the existing bioaccessibilit... [more]

Recent decades have seen a growing popularity of in vitro bioaccessibility being utilised as a screening tool in human health risk assessment. However the existing bioaccessibility studies only focus on single contaminant. Considering human are likely to ingest multi-contaminants, these contaminants could interact within human gastrointestinal tract which may lead to an increase or decrease in bioaccessibility. In this study, seven different types of soil were spiked with arsenic (As) or cadmium (Cd) and aged for one year. The effects of soil properties on the bioaccessibility were examined. Moreover, the interaction between As and Cd in simulated human digestive system was studied by mixing As-spiked soil with Cd-spiked soil of the same type during bioaccessibility test. Results shows the bioaccessibility of As ranged from 40 ± 2.8 to 95 ± 1.3% in the gastric phase and 16 ± 2.0 to 96 ± 0.8% in the intestinal phase whilst a significant difference was observed between Cd gastric bioaccessibility (72 ± 4.3 to 99 ± 0.8%) and intestinal bioaccessibility (6.2 ± 0.3 to 45 ± 2.7%). Organic carbon, iron oxide and aluminium oxide were key parameters influencing the bioaccessibility of As (gastric and intestinal phases) and Cd (intestinal phase). No interactions between As and Cd during bioaccessibility test were observed in any soils, which indicates As and Cd may age independently and did not interact while being solubilised during bioaccessibility test. Thus additive effect may be proposed when estimating the bioaccessibility of mixtures of independently-aged As and Cd in soils.

DOI 10.1016/j.chemosphere.2015.12.091
Citations Scopus - 39Web of Science - 29
Co-authors Megh Mallavarapu
2016 Laghari M, Naidu R, Xiao B, Hu Z, Mirjat MS, Hu M, et al., 'Recent developments in biochar as an effective tool for agricultural soil management: a review', JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, 96 4840-4849 (2016) [C1]
DOI 10.1002/jsfa.7753
Citations Scopus - 119Web of Science - 84
2016 Sarkar B, Neumann A, Naidu R, 'Clay and fine particle-based materials for environmental technologies and clean up', APPLIED CLAY SCIENCE, 134 69-70 (2016)
DOI 10.1016/j.clay.2016.10.026
2016 Ramakrishnan P, Nagarajan S, Thiruvenkatam V, Palanisami T, Naidu R, Mallavarapu M, Rajendran S, 'Cation doped hydroxyapatite nanoparticles enhance strontium adsorption from aqueous system: A comparative study with and without calcination', APPLIED CLAY SCIENCE, 134 136-144 (2016) [C1]
DOI 10.1016/j.clay.2016.09.022
Citations Scopus - 29Web of Science - 22
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Chekli L, Brunetti G, Marzouk ER, Maoz-Shen A, Smith E, Naidu R, et al., 'Evaluating the mobility of polymer-stabilised zero-valent iron nanoparticles and their potential to co-transport contaminants in intact soil cores', ENVIRONMENTAL POLLUTION, 216 636-645 (2016) [C1]
DOI 10.1016/j.envpol.2016.06.025
Citations Scopus - 25Web of Science - 17
2016 Matheyarasu R, Seshadri B, Bolan NS, Naidu R, 'Assessment of nitrogen losses through nitrous oxide from abattoir wastewater-irrigated soils', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 23 22633-22646 (2016) [C1]
DOI 10.1007/s11356-016-7438-y
Citations Scopus - 7Web of Science - 6
Co-authors Nanthi Bolan
2016 Prasath A, Panneerselvan L, Provatas A, Naidu R, Megharaj M, 'Genotoxicity assessment of acute exposure of 2, 4-dinitroanisole, its metabolites and 2, 4, 6-trinitrotoluene to Daphnia carinata', ECOTOXICOLOGY, 25 1873-1879 (2016) [C1]
DOI 10.1007/s10646-016-1709-8
Citations Scopus - 16Web of Science - 13
Co-authors Megh Mallavarapu, Logeshwaran Panneerselvan
2016 Kader M, Lamb DT, Wang L, Megharaj M, Naidu R, 'Predicting copper phytotoxicity based on pore-water pCu', ECOTOXICOLOGY, 25 481-490 (2016) [C1]
DOI 10.1007/s10646-015-1605-7
Citations Scopus - 14Web of Science - 14
Co-authors Liang Wang, Megh Mallavarapu
2016 Xia Q, Peng C, Lamb D, Kader M, Mallavarapu M, Naidu R, Ng JC, 'Effects of arsenic and cadmium on bioaccessibility of lead in spiked soils assessed by Unified BARGE Method', CHEMOSPHERE, 154 343-349 (2016) [C1]
DOI 10.1016/j.chemosphere.2016.03.133
Citations Scopus - 9Web of Science - 7
Co-authors Megh Mallavarapu
2016 Kader M, Lamb DT, Mahbub KR, Megharaj M, Naidu R, 'Predicting plant uptake and toxicity of lead (Pb) in long-term contaminated soils from derived transfer functions', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 23 15460-15470 (2016) [C1]
DOI 10.1007/s11356-016-6696-z
Citations Scopus - 12Web of Science - 11
Co-authors Megh Mallavarapu
2016 Matheyarasu R, Bolan NS, Naidu R, 'Abattoir Wastewater Irrigation Increases the Availability of Nutrients and Influences on Plant Growth and Development', Water, Air, and Soil Pollution, 227 (2016) [C1]

This study evaluated the effects of abattoir wastewater irrigation on plant growth and development. The soils used in this study were collected from Primo Smallgoods Abattoir (Por... [more]

This study evaluated the effects of abattoir wastewater irrigation on plant growth and development. The soils used in this study were collected from Primo Smallgoods Abattoir (Port Wakefield, South Australia) at different sites such as currently irrigated (CI), currently not irrigated (CNI) and soil outside the irrigation area as control (CTRL). A completely randomised block design was employed for the plant growth experiment, where four crops (Pennisetum purpureum, Medicago sativa, Sinapis alba and Helianthus annuus) were grown separately on three different soils (CI, CNI and CTRL) in plastic pots. Two types of water (tap water and wastewater) and two loadings were applied throughout the planting period based on the field capacity (FC 100 and 150¿%). The overall dry matter yield was compared between the soils and treatments. Under wastewater irrigation, among the four species grown in the CI soil, P. purpureum (171¿g) and H. annuus (151¿g) showed high biomass yields, followed by S. alba (115¿g) and M. sativa (31¿g). The plants grown under tap water showed about 70¿% lower yields compared to the abattoir wastewater irrigation (AWW). Similar trends in the biomass yields were observed for CNI and CTRL soils under the two water treatments, with the biomass yields in the following order CI > CNI > CTRL soils. The results confirm the beneficial effects of AWW at the greenhouse level. However, a proper cropping pattern and wastewater irrigation management plan is essential to utilise the nutrients available in the wastewater-irrigated land treatment sites. The increase in fertility is evident from the effects of wastewater on biomass growth and also the abundance of nutrients accumulated in plants. A mass balance calculation on the applied, residual and the plant-accumulated nutrients over a few cropping periods will help us in understanding the nutrient cycling processes involved in the abattoir-irrigated land treatment sites, which will serve as an effective tool for the environmental management.

DOI 10.1007/s11270-016-2947-3
Citations Scopus - 32Web of Science - 25
Co-authors Nanthi Bolan
2016 Kuppusamy S, Thavamani P, Megharaj M, Lee YB, Naidu R, 'Kinetics of PAH degradation by a new acid-metal-tolerant Trabulsiella isolated from the MGP site soil and identification of its potential to fix nitrogen and solubilize phosphorous', JOURNAL OF HAZARDOUS MATERIALS, 307 99-107 (2016) [C1]
DOI 10.1016/j.jhazmat.2015.12.068
Citations Scopus - 32Web of Science - 30
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Soil bacterial strains with heavy metal resistance and high potential in degrading diesel oil and n-alkanes', International Journal of Environmental Science and Technology, 13 2863-2874 (2016) [C1]

Four bacterial strains, capable of degrading diesel oil, n-alkanes or hexadecane, were isolated from soils contaminated with petroleum oil and identified. Strains of Pseudomonas s... [more]

Four bacterial strains, capable of degrading diesel oil, n-alkanes or hexadecane, were isolated from soils contaminated with petroleum oil and identified. Strains of Pseudomonas sp., Pseudomonas putida TPHK-1 and Pseudomonas aeruginosa TPHK-4, were more efficient in degrading high concentrations of the hydrocarbons than the other two strains, Stenotrophomonas maltophilia TPHK-2 and Acenitobacter sp. TPHK-3. P. putida TPHK-1 exhibited tolerance to very high concentrations of heavy metals such as cadmium, lead, zinc and copper. The innate ability of P. putida TPHK-1, as evidenced by the amplified genes alkB1 and alkB2 that encode alkane hydroxylases, and cat12o and cat23o coding for catechol dioxygenase, in degrading diesel oil in the presence of heavy metals is far greater than that of the strains reported in the literature. Heavy metal tolerance coupled with rapid degradation of hydrocarbons, even at high concentrations, suggests that P. putida TPHK-1 has a great potential in remediating soils contaminated with mixtures of hydrocarbons and heavy metals.

DOI 10.1007/s13762-016-1113-1
Citations Scopus - 27Web of Science - 22
Co-authors Megh Mallavarapu, Kavitha Ramadass
2016 Liu E, Sarkar B, Wang L, Naidu R, 'Copper-complexed clay/poly-acrylic acid composites: Extremely efficient adsorbents of ammonia gas', Applied Clay Science, 121-122 154-161 (2016) [C1]

Work reported in this manuscript takes into consideration the possible use of NH3 gas by terrorists and the potential for an effective and rapid removal of such toxic substance fr... [more]

Work reported in this manuscript takes into consideration the possible use of NH3 gas by terrorists and the potential for an effective and rapid removal of such toxic substance from air using a modified clay material. In this study, a series of clay/polymer composites were synthesised for ammonia gas (NH3) adsorption. The adsorbents were prepared by polymerisation of acrylic acid with N,N'-methylenebisacrylamide (MBA) as cross-linker in the presence of a large amount of highly dispersed clay nanoparticles, followed by interaction with copper ions (Cu2+). Two kinds of clays were used. One was an acid-treated bentonite that had a specific surface area (SSA) of 395 m2/g and the other was natural palygorskite with a SSA of 87 m2/g. The materials were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption-desorption and Fourier transform infrared spectroscopy (FTIR). The materials' ability to remove NH3 was investigated using NH3 breakthrough dynamic test while the strength of NH3 retention was characterised by Thermogravimetric Analysis (TGA) coupled with FTIR. The results indicate that clay/poly-acrylic acid composites are highly efficient adsorbents of NH3 after binding with Cu2+. Trapping NH3 on such adsorbents can lead to colour change and this makes it possible to predict the lifetime of the adsorption bed visually. In addition, the result of NH3 release from the material following adsorption showed that majority of the adsorbed NH3 desorbed at temperature above 180°C. The clay/polymer composites can potentially be used in air filters. They may provide an effective and cheap way for removing NH3 from contaminated air.

DOI 10.1016/j.clay.2015.12.012
Citations Scopus - 19Web of Science - 16
Co-authors Liang Wang
2016 Kuppusamy S, Thavamani P, Megharaj M, Lee YB, Naidu R, 'Polyaromatic hydrocarbon (PAH) degradation potential of a new acid tolerant, diazotrophic P-solubilizing and heavy metal resistant bacterium Cupriavidus sp. MTS-7 isolated from long-term mixed contaminated soil', Chemosphere, 162 31-39 (2016) [C1]

An isolate of Cupriavidus (strain MTS-7) was identified from a long-term PAHs and heavy metals mixed contaminated soil with the potential to biodegrade both LMW and HMW PAHs with ... [more]

An isolate of Cupriavidus (strain MTS-7) was identified from a long-term PAHs and heavy metals mixed contaminated soil with the potential to biodegrade both LMW and HMW PAHs with added unique traits of acid and alkali tolerance, heavy metal tolerance, self-nutrient assimilation by N fixation and P solubilization. This strain completely degraded the model 3 (150¿mg¿L-1 Phe), 4 (150¿mg¿L-1 Pyr) and 5 (50¿mg¿L-1 BaP) ring PAHs in 4, 20 and 30 days, respectively. It could mineralize 90¿100% of PAHs (200¿mg¿L-1 of Phe and Pyr) within 15 days across pH ranging from 5 to 8 and even in the presence of toxic metal contaminations. During biodegradation, the minimum inhibitory concentrations were 5 (Cu2+) and 3 (Cd2+, Pb2+, Zn2+) mg L-1 of the potentially bioavailable metal ions and over 17¿mg¿L-1 metal levels was lethal for the microbe. Further, it could fix 217¿274¿µg¿mL-1 of N and solubilize 79¿135¿µg¿mL-1 of P while PAHs degradation. MTS-7 as a superior candidate could be thus used in the enhanced bioaugmentation and/or phytoremediation of long-term mixed contaminated sites.

DOI 10.1016/j.chemosphere.2016.07.052
Citations Scopus - 45Web of Science - 34
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Fang C, Chen Z, Megharaj M, Naidu R, 'Potentiometric detection of AFFFs based on MIP', Environmental Technology &amp; Innovation, 5 52-59 (2016) [C1]
DOI 10.1016/j.eti.2015.12.003
Citations Scopus - 32Web of Science - 21
Co-authors Cheng Fang, Megh Mallavarapu
2016 Yirsaw BD, Megharaj M, Chen Z, Naidu R, 'Reduction of hexavalent chromium by green synthesized nano zero valent iron and process optimization using response surface methodology', Environmental Technology &amp; Innovation, 5 136-147 (2016) [C1]
DOI 10.1016/j.eti.2016.01.005
Citations Scopus - 48Web of Science - 39
Co-authors Megh Mallavarapu
2016 He W, Megharaj M, Naidu R, 'Toxicity of perfluorooctanoic acid towards earthworm and enzymatic activities in soil', Environmental Monitoring and Assessment, 188 (2016) [C1]

Perfluorooctanoic acid (PFOA) is a widespread persistent organic contaminant in the environment that has recently raised much of regulatory and public concern. Therefore, assessme... [more]

Perfluorooctanoic acid (PFOA) is a widespread persistent organic contaminant in the environment that has recently raised much of regulatory and public concern. Therefore, assessment of its ecological risk is a top priority research. Hence, this study investigated the toxicity of PFOA to beneficial microbial processes in the soil such as activities of dehydrogenase, urease and potential nitrification in addition to earthworm survival, weight loss and PFOA bioaccumulation in two contrasting soils. In general, PFOA caused inhibition of all the measured microbial processes in a dose-dependent manner and the inhibition was higher in Williamtown (WT) soil than Edinburgh (EB) soil. Thus, WT soil being sandy in nature with low clay content showed higher PFOA bioavailability and hence showed higher toxicity. There was no mortality in earthworms exposed up to 100¿mg PFOA/kilogram soil in both the soils; however, there was a significant weight loss from 25¿mg/kg onwards. This study clearly demonstrates that soil contamination of PFOA can lead to adverse effects on soil health.

DOI 10.1007/s10661-016-5416-y
Citations Scopus - 27Web of Science - 20
Co-authors Megh Mallavarapu
2016 Abbasian F, Lockington R, Megharaj M, Naidu R, 'The Biodiversity Changes in the Microbial Population of Soils Contaminated with Crude Oil', Current Microbiology, 72 663-670 (2016) [C1]

Crude oil spills resulting from excavation, transportation and downstream processes can cause intensive damage to living organisms and result in changes in the microbial populatio... [more]

Crude oil spills resulting from excavation, transportation and downstream processes can cause intensive damage to living organisms and result in changes in the microbial population of that environment. In this study, we used a pyrosequencing analysis to investigate changes in the microbial population of soils contaminated with crude oil. Crude oil contamination in soil resulted in the creation of a more homogenous population of microorganisms dominated by members of the Actinomycetales, Clostridiales and Bacillales (all belonging to Gram-positive bacteria) as well as Flavobacteriales, Pseudomonadales, Burkholderiales, Rhizobiales and Sphingomonadales (all belonging to Gram-negative bacteria). These changes in the biodiversity decreased the ratios of chemoheterotrophic bacteria at higher concentrations of crude oil contamination, with these being replaced by photoheterotrophic bacteria, mainly Rhodospirillales. Several of the dominant microbial orders in the crude oil contaminated soils are able to degrade crude oil hydrocarbons and therefore are potentially useful for remediation of crude oil in contaminated sites.

DOI 10.1007/s00284-016-1001-4
Citations Scopus - 53Web of Science - 43
Co-authors Megh Mallavarapu
2016 Mandal S, Sarkar B, Bolan N, Novak J, Ok YS, Van Zwieten L, et al., 'Designing advanced biochar products for maximizing greenhouse gas mitigation potential', Critical Reviews in Environmental Science and Technology, 46 1367-1401 (2016) [C1]

Greenhouse gas (GHG) emissions from agricultural operations continue to increase. Carbon (C)-enriched char materials like biochar have been described as a mitigation strategy. Uti... [more]

Greenhouse gas (GHG) emissions from agricultural operations continue to increase. Carbon (C)-enriched char materials like biochar have been described as a mitigation strategy. Utilization of biochar material as a soil amendment has been demonstrated to provide potentially greater soil GHG suppression due to its interactions in the soil system. However, these effects are variable and the duration of the impact remains uncertain. Various (nano)materials can be used to modify chars to obtain surface functionality to mitigate GHG emissions. This review critically focusses on the innovative methodologies for improving char efficiency, underpinning GHG mitigation and C sequestration.

DOI 10.1080/10643389.2016.1239975
Citations Scopus - 78Web of Science - 61
Co-authors Nanthi Bolan, Girish Choppala
2016 Duan L, Naidu R, Liu Y, Dong Z, Mallavarapu M, Herde P, et al., 'Comparison of oral bioavailability of benzo[a]pyrene in soils using rat and swine and the implications for human health risk assessment', Environment International, 94 95-102 (2016) [C1]

Background: There are many uncertainties concerning variations in benzo[a]pyrene (B[a]P) soil guidelines protecting human health based on carcinogenic data obtained in animal stud... [more]

Background: There are many uncertainties concerning variations in benzo[a]pyrene (B[a]P) soil guidelines protecting human health based on carcinogenic data obtained in animal studies. Although swine is recognised as being much more representative of the human child in terms of body size, gut physiology and genetic profile the rat/mice model is commonly used in practice. Objectives: We compare B[a]P bioavailability using a rat model to that estimated in a swine model, to investigate the correlation between these two animal models. This may help reduce uncertainty in applying bioavailability to human health risk assessment. Methods: Twelve spiked soil samples and a spiked silica sand (reference material) were dosed to rats in parallel with a swine study. B[a]P bioavailability was estimated by the area under the plasma B[a]P concentration-time curve (AUC) and faecal excretion as well in the rats. Direct comparison between the two animal models was made for: firstly, relative bioavailability (RB) using AUC assay; and secondly, the two assays in the rat model. Results: Both AUC and faecal excretion assays showed linear dose-response for the reference material. However, absolute bioavailability was significantly higher when using faecal excretion assay (p < 0.001). In aged soils faecal excretion estimated based on solvent extraction was not accurate due to the form of non-extractable fraction through ageing. A significant correlation existed between the two models using RB for soil samples (RBrat = 0.26RBswine + 17.3, R2 = 0.70, p < 0.001), despite the regression slope coefficient revealing that the rat model would underestimate RB by about one quarter compared to using swine. Conclusions: In the comparison employed in this study, an interspecies difference of four in RB using AUC assay was identified between the rat and swine models regarding pharmacokinetic differences, which supported the body weight scaling method recommended by US EPA. Future research should focus on the carcinogenic competency (pharmacodynamics) used in experiment animals and humans.

DOI 10.1016/j.envint.2016.04.041
Citations Scopus - 20Web of Science - 15
Co-authors Yanju Liu, Megh Mallavarapu
2016 Wang L, Fang C, Cheng Y, Lamb D, Chen Z, Megharaj M, Naidu R, 'A practical way to make solid-state reference electrodes', Journal of Biochemistry and Analytical studies, 1 1-5 (2016) [C1]
DOI 10.16966/jbt.101
Co-authors Ying Cheng, Megh Mallavarapu, Cheng Fang, Liang Wang
2016 Mandal A, Biswas B, Sarkar B, Patra AK, Naidu R, 'Surface tailored organobentonite enhances bacterial proliferation and phenanthrene biodegradation under cadmium co-contamination', Science of the Total Environment, 550 611-618 (2016) [C1]

Co-contamination of soil and water with polycyclic aromatic hydrocarbon (PAH) and heavy metals makes biodegradation of the former extremely challenging. Modified clay-modulated mi... [more]

Co-contamination of soil and water with polycyclic aromatic hydrocarbon (PAH) and heavy metals makes biodegradation of the former extremely challenging. Modified clay-modulated microbial degradation provides a novel insight in addressing this issue. This study was conducted to evaluate the growth and phenanthrene degradation performance of Mycobacterium gilvum VF1 in the presence of a palmitic acid (PA)-grafted Arquad® 2HT-75-based organobentonite in cadmium (Cd)-phenanthrene co-contaminated water. The PA-grafted organobentonite (ABP) adsorbed a slightly greater quantity of Cd than bentonite at up to 30 mg L-1 metal concentration, but its highly negative surface charge imparted by carboxylic groups indicated the potential of being a significantly superior adsorbent of Cd at higher metal concentrations. In systems co-contained with Cd (5 and 10 mg L-1), the Arquad® 2HT-75-modified bentonite (AB) and PA-grafted organobentonite (ABP) resulted in a significantly higher (72-78%) degradation of phenanthrene than bentonite (62%) by the bacterium. The growth and proliferation of bacteria were supported by ABP which not only eliminated Cd toxicity through adsorption but also created a congenial microenvironment for bacterial survival. The macromolecules produced during ABP-bacteria interaction could form a stable clay-bacterial cluster by overcoming the electrostatic repulsion among individual components. Findings of this study provide new insights for designing clay modulated PAH bioremediation technologies in mixed-contaminated water and soil.

DOI 10.1016/j.scitotenv.2016.01.164
Citations Scopus - 30Web of Science - 27
Co-authors Bhaba Biswas
2016 Nirola R, Megharaj M, Venkateswarlu K, Aryal R, Correll R, Naidu R, 'Assessment of metal toxicity and bioavailability in metallophyte leaf litters and metalliferous soils using Eisenia fetida in a microcosm study', Ecotoxicology and Environmental Safety, 129 264-272 (2016) [C1]

The leaf litters of tree species, Acacia pycnantha (Ap) and Eucalyptus camaldulensis (Ec), predominantly growing at an abandoned copper (Cu) mine and mine soils including controls... [more]

The leaf litters of tree species, Acacia pycnantha (Ap) and Eucalyptus camaldulensis (Ec), predominantly growing at an abandoned copper (Cu) mine and mine soils including controls, were assessed for determining the metal toxicity and bioavailability using earthworm species Eisenia fetida, in a microcosm. Significant reduction in body weight as well as mortality were observed when the worms were introduced into mine soil or its combination with mine Ap litter. Virtually, there were no juveniles when the worms were fed on substratum that contained mine soil or mine leaf litter. The extent of bioaccumulation was dependent on water-soluble fraction of a metal in soil. The accumulation of cadmium, lead and copper in worm tissue was significantly more in treatments that received mine soil with or without mine leaf litter. However, the tissue concentration of zinc did not differ much in earthworms irrespective of its exposure to control or contaminated samples. Mine leaf litter from Ec, a known Cu hyperaccumulator, was more hospitable to earthworm survival and juvenile than that of Ap litter. Validation of the data on bioaccumulation of metals indicated that the mine leaf litter significantly contributed to metal bioavailability. However, it was primarily the metal concentration in mine soil that was responsible for earthworm toxicity and bioavailability. Our data also indicate that detrivores like earthworm is greatly responsible for heavy metal transfer from mines into the ecosystem.

DOI 10.1016/j.ecoenv.2016.03.034
Citations Scopus - 9Web of Science - 8
Co-authors Megh Mallavarapu
2016 Chen Y, Yu B, Lin J, Naidu R, Chen Z, 'Simultaneous adsorption and biodegradation (SAB) of diesel oil using immobilized Acinetobacter venetianus on porous material', Chemical Engineering Journal, 289 463-470 (2016) [C1]

This paper investigated modified bamboo charcoal (MBC) as a cheap, abundant and alternative cell immobilization matrix for biodegrading diesel oil. The immobilized microorganism&a... [more]

This paper investigated modified bamboo charcoal (MBC) as a cheap, abundant and alternative cell immobilization matrix for biodegrading diesel oil. The immobilized microorganism's degradation capacity was compared to its free form counterparts, namely planktonic and immobilized bacteria which degraded relatively high amounts of diesel oil (>80%). Acinetobacter venetianus immobilized on MBC demonstrated superior efficiency in degrading diesel oil (94%) compared to planktonic cells culture (82%) over a 3-day period. Moreover, the simultaneous adsorption and biodegradation of diesel oil using these immobilized cells fitted well to the pseudo second order (R2 > 0.99). Scanning electron microscopy (SEM) revealed that through absorption, cells attached well to the cavum of MBC stalk cells. Fourier transform infrared analysis (FTIR) revealed that a large number of bands at 1300-1500 cm-1 existed, demonstrating that the diesel oil was degraded and new bands were formed. Gas Chromatography Mass Spectrum (GC-MS) analysis indicated the immobilized cells could degrade diesel oil into esters and aldehydes. Results justified the applicability of MBC as the carrier matrix for immobilizing microorganisms in removing diesel oil compounds from industrial wastewater.

DOI 10.1016/j.cej.2016.01.010
Citations Scopus - 80Web of Science - 61
2016 Liu E, Sarkar B, Chen Z, Naidu R, 'Decontamination of chlorine gas by organic amine modified copper-exchanged zeolite', Microporous and Mesoporous Materials, 225 450-455 (2016) [C1]

Removal of chlorine gas (Cl2) from air is of critical requirement in order to address point-source emissions possibly during a terrorist attack or an industrial accident resulting... [more]

Removal of chlorine gas (Cl2) from air is of critical requirement in order to address point-source emissions possibly during a terrorist attack or an industrial accident resulting in Cl2 contamination of the atmosphere. In this work, copper (Cu) exchanged zeolite Y (CuY) was functionalised with triethylenediamine (TEDA) and the capacity to remove Cl2 was evaluated. The materials were characterised by nitrogen (N2) adsorption-desorption studies, Fourier Transform Infrared (FTIR) spectroscopy and X-ray Photoelectron Spectroscopy (XPS). The materials' ability to remove Cl2 was investigated via a dynamic breakthrough test. Copper exchanged zeolite displayed a low adsorption of Cl2 in spite of its large surface area. However, Cl2 removal greatly improved following functionalisation with TEDA. XPS analysis revealed that Cl2 was removed via a catalytic hydrolysis reaction where adsorbed water vapour transformed Cl2 into Cl- which could be further trapped in the zeolite structural framework. Moisture could increase the Cl2 removal capacity, but the competition for adsorption between water and chlorine molecules was also observed. The spent adsorbent after exposure to Cl2 could be easily recycled with an excessive water vapour treatment. The reusability was also investigated and the adsorbent could be used for more than five times. This material can potentially be used in air filters. It may provide an efficient way for decontaminating Cl2 during a terrorist attack or an industrial accident.

DOI 10.1016/j.micromeso.2016.01.023
Citations Scopus - 15Web of Science - 13
2016 Bahar MM, Megharaj M, Naidu R, 'Influence of phosphate on toxicity and bioaccumulation of arsenic in a soil isolate of microalga Chlorella sp.', Environmental Science and Pollution Research, 23 2663-2668 (2016) [C1]

In this study, the toxicity, biotransformation and bioaccumulation of arsenite and arsenate in a soil microalga, Chlorella sp., were investigated using different phosphate levels.... [more]

In this study, the toxicity, biotransformation and bioaccumulation of arsenite and arsenate in a soil microalga, Chlorella sp., were investigated using different phosphate levels. The results indicated that arsenate was highly toxic than arsenite to the alga, and the phosphate limitation in growth media greatly enhanced arsenate toxicity. The uptake of arsenate in algal cells was more than that of arsenite, and the predominant species in the growth media was arsenate after 8¿days of exposure to arsenite or arsenate, indicating arsenite oxidation by this microalga. Arsenate reduction was also observed when the alga was incubated in a phosphate-limiting growth medium. Similar to the process of biotransformation, the alga accumulated more arsenic when it was exposed to arsenate and preferably more in a phosphate-limiting condition. Although phosphate significantly influences the biotransformation and bioaccumulation of arsenic, the oxidizing ability and higher accumulation capacity of this alga have great potential for its application in arsenic bioremediation.

DOI 10.1007/s11356-015-5510-7
Citations Scopus - 40Web of Science - 32
Co-authors Megh Mallavarapu, Mezbaul Bahar
2016 Wang L, Cheng Y, Lamb D, Chen Z, Lesniewski P, Mallavarapu M, Naidu R, 'Simultaneously determining multi-metal ions using an Ion Selective Electrode array system', Environmental Technology & Innovation, 6 165-176 (2016) [C1]
DOI 10.1016/j.eti.2016.10.001
Citations Scopus - 17Web of Science - 12
Co-authors Liang Wang, Megh Mallavarapu, Ying Cheng
2016 Kunhikrishnan A, Thangarajan R, Bolan NS, Xu Y, Mandal S, Gleeson DB, et al., 'Functional Relationships of Soil Acidification, Liming, and Greenhouse Gas Flux', Advances in Agronomy, 139 1-71 (2016) [C1]
DOI 10.1016/bs.agron.2016.05.001
Citations Scopus - 145Web of Science - 118
Co-authors Nanthi Bolan
2016 Lamb DT, Kader M, Ming H, Wang L, Abbasi S, Megharaj M, Naidu R, 'Predicting plant uptake of cadmium: validated with long-term contaminated soils', ECOTOXICOLOGY, 25 1563-1574 (2016) [C1]
DOI 10.1007/s10646-016-1712-0
Citations Scopus - 22Web of Science - 18
Co-authors Liang Wang, Megh Mallavarapu
2016 Kuppusamy S, Thavamani P, Megharaj M, Venkateswarlu K, Naidu R, 'Agronomic and remedial benefits and risks of applying biochar to soil: Current knowledge and future research directions', Environment International, 87 1-12 (2016) [C1]

&apos;Biochar&apos; represents an emerging technology that is increasingly being recognized for its potential role in carbon sequestration, reducing greenhouse gas emissions, wast... [more]

'Biochar' represents an emerging technology that is increasingly being recognized for its potential role in carbon sequestration, reducing greenhouse gas emissions, waste management, renewable energy, soil improvement, crop productivity enhancement and environmental remediation. Published reviews have so far focused mainly on the above listed agronomic and environmental benefits of applying biochar, yet paid little or no attention to its harmful effects on the ecological system. This review highlights a balanced overview of the advantages and disadvantages of the pyrolysis process of biochar production, end-product quality and the benefits versus drawbacks of biochar on: (a) soil geochemistry and albedo, (b) microflora and fauna, (c) agrochemicals, (d) greenhouse gas efflux, (e) nutrients, (f) crop yield, and (g) contaminants (organic and inorganic). Future research should focus more on the unintended long-term consequences of biochar on biological organisms and their processes in the soil.

DOI 10.1016/j.envint.2015.10.018
Citations Scopus - 279Web of Science - 214
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Kader M, Lamb DT, Megharaj M, Naidu R, 'Sorption parameters as a predictor of arsenic phytotoxicity in Australian soils', Geoderma, 265 103-110 (2016) [C1]

Arsenic (As) is a mobile and ecotoxic metalloid that is of serious concern to the environment. In this study, As phytotoxicity was studied using a dose-response approach for seven... [more]

Arsenic (As) is a mobile and ecotoxic metalloid that is of serious concern to the environment. In this study, As phytotoxicity was studied using a dose-response approach for seven contrasting soils considering 3 end-points (shoot biomass, root elongation and chlorophyll content) and focusing on predictors of toxicity. Root elongation study was carried out for 4days using both Cucumis sativus L. (cucumber) and Triticum aestivum L. (wheat) and shoot end-points with a 4week a pot study using cucumber only. Root elongation of cucumber was a substantially less sensitive indicator to As than data from the 4weeks pot study. Effective concentrations (50%)(EC50) from cucumber root elongation studies were overall 1.6 times higher than the 4week shoot data. Cucumber was however considerably more sensitive to wheat. Given the large discrepancy in phytotoxicity end points for 7 soils, root elongation data for ecotoxicological assessment should be treated with some caution. Arsenic phytotoxicity was strongly related to the sorption constants of each of the seven soils in our study. Both root elongation and shoot data were related strongly to Freundlich partitioning constants (Kf) (L/kg). Wheat and cucumber root elongation had R2 values 0.90 and 0.91 respectively, while cucumber shoot data was 0.79. The Kf values were related to soil pH and also EC50 data and, thus, shows that As phytotoxicity in our study was primarily controlled by sorption reactions. The rate of As bioaccumulation to cucumber shoots depended heavily on the soil under consideration. Chlorophyll and carotenoid content of cucumber shoots increased with As content in 3 soils and decreased in other soils.

DOI 10.1016/j.geoderma.2015.11.019
Citations Scopus - 33Web of Science - 23
Co-authors Megh Mallavarapu
2016 Ming H, Naidu R, Sarkar B, Lamb DT, Liu Y, Megharaj M, Sparks D, 'Competitive sorption of cadmium and zinc in contrasting soils', Geoderma, 268 60-68 (2016) [C1]

The sorption behavior of cadmium (Cd(II)) and zinc (Zn(II)) on two virgin soils with different pH levels was studied using single metal and competitive dual metal systems. In the ... [more]

The sorption behavior of cadmium (Cd(II)) and zinc (Zn(II)) on two virgin soils with different pH levels was studied using single metal and competitive dual metal systems. In the single metal system, Zn exhibited a greater affinity for the alkaline soil, as indicated by the Langmuir constant (KL = 8.85 L/kg) compared with Cd (KL = 1.79 L/kg). However, much less sorption of both Zn (KL = 0.19 L/kg) and Cd (KL = 0.07 L/kg) was observed in the acidic soil. The competitive sorption data were modeled using two-metal Freundlich and Langmuir functions. The competition for metal sorption occurred in the alkaline soil only at a higher concentration of the competing metals, whereas the effect was significant even at lower concentrations in the acidic soil. The cumulative amount of both metals sorbed in the soil was similar to that of single metal systems in the studied concentration range, demonstrating that the number of sites available for sorption remained constant irrespective of the competition. This study indicated that Cd might be more mobile in a mixed-metal system than in a single-metal scenario and thus poses a serious ecotoxicological threat. This study is important for assessing the risks and developing management strategies for multiple heavy metal contaminated soils.

DOI 10.1016/j.geoderma.2016.01.021
Citations Scopus - 46Web of Science - 38
Co-authors Yanju Liu, Megh Mallavarapu
2016 Jin X, Zheng M, Sarkar B, Naidu R, Chen Z, 'Characterization of bentonite modified with humic acid for the removal of Cu (II) and 2,4-dichlorophenol from aqueous solution', APPLIED CLAY SCIENCE, 134 89-94 (2016) [C1]
DOI 10.1016/j.clay.2016.09.036
Citations Scopus - 36Web of Science - 27
2016 Kuppusamy S, Thavamani P, Megharaj M, Naidu R, 'Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by novel bacterial consortia tolerant to diverse physical settings - Assessments in liquid- and slurry-phase systems', International Biodeterioration and Biodegradation, 108 149-157 (2016) [C1]

Field-scale bioremediation of PAHs contaminated soils have proved to be difficult and challenging due to inhibited growth of PAH degrading microbes. In this study, for the first t... [more]

Field-scale bioremediation of PAHs contaminated soils have proved to be difficult and challenging due to inhibited growth of PAH degrading microbes. In this study, for the first time mixed bacterial cultures designated as consortia-A and N were developed using elite metal or acid tolerant, N-fixing, P-solubilizing and biosurfactant producing PAH degraders enriched from manufactured gas plant sites. The two consortia could degrade both LMW and HMW PAHs. Kinetic studies of PAH degradation by the consortia showed the highest biodegradation rate constants (k = 0.027-0.61 day-1) and lowest half-life time (t1/2 = 1-26 days) values reported to date in liquid cultures and highlighted the use of consortium-A for the remediation of acidic soils due to its tolerance up to pH 5. Furthermore, bioaugmentation of these consortia has proven to be effective in degradation of LMW (>95%) and HMW (90%) PAHs from spiked soil slurries. Amendment of consortia-A and N exhibited 10.7 and 44.3% more total PAHs degradation, respectively than natural attenuation in 60 days even from the real long-term mixed contaminated soils. Thus the results of this study demonstrate the great potential of these novel bacterial consortia, particularly consortium-N for use in field-scale bioremediation of PAHs in long-term mixed contaminated neutral soils.

DOI 10.1016/j.ibiod.2015.12.013
Citations Scopus - 82Web of Science - 64
Co-authors Thava Palanisami, Megh Mallavarapu
2016 Kuppusamy S, Thavamani P, Megharaj M, Venkateswarlu K, Lee YB, Naidu R, 'Potential of Melaleuca diosmifolia as a novel, non-conventional and low-cost coagulating adsorbent for removing both cationic and anionic dyes', Journal of Industrial and Engineering Chemistry, 37 198-207 (2016) [C1]

© 2016 The Korean Society of Industrial and Engineering Chemistry.The potential of dried twigs of Melaleuca diosmifolia as a novel biosorbent for removing three cationic dyes, met... [more]

© 2016 The Korean Society of Industrial and Engineering Chemistry.The potential of dried twigs of Melaleuca diosmifolia as a novel biosorbent for removing three cationic dyes, methylene blue (MB), acridine orange (AO) and malachite green (MG), and an anionic dye, eriochrome black T (EB) was evaluated in a batch adsorption process. Notably, the biosorbent removed 77-99% of both cationic and anionic dyes in a wide ranging pH of 2-10, and the reactions were endothermic. The dye adsorption equilibria were rapidly attained within 3 h. The monolayer adsorption capacity of the sorbent added at 5 g L-1 was 119.05, 126.8, 116.28 and 94.34 mg g-1 for MB, AO, MG and EB, respectively. The water extract obtained from the plant material induced fast decolourization of both categories of dyes followed by gradual flocculation, indicating its potential as a natural coagulant. Gas chromatographic analysis also indicated that the main electrostatic attraction between 1,8-cineole, 1-p-methene-8-thiol and furfural compounds of the biomaterial, and dye molecules resulted in the formation of initial supramolecular complexes which further progressed into strong aggregates, leading to precipitation of dye-biomaterial complexes. Subsequently, the overall complex mechanism of dye removal was confirmed to be a combined process of adsorption and coagulation. Consistent with the batch studies, using selected plant material in real environmental water samples also resulted in effective dye removal, highlighting its potential for use in wastewater treatment.

DOI 10.1016/j.jiec.2016.03.021
Citations Scopus - 27Web of Science - 27
Co-authors Megh Mallavarapu, Thava Palanisami
2016 Naidu R, Jit J, Arias V, Kennedy B, 'Emerging contaminant uncertainties and policy: The chicken or the egg conundrum', Chemosphere, 154 385-390 (2016) [C1]
DOI 10.1016/j.chemosphere.2016.03.110
Citations Scopus - 35Web of Science - 22
2015 Ortega-Calvo J-J, Harmsen J, Parsons JR, Semple KT, Aitken MD, Ajao C, et al., 'From Bioavailability Science to Regulation of Organic Chemicals', ENVIRONMENTAL SCIENCE & TECHNOLOGY, 49 10255-10264 (2015) [C1]
DOI 10.1021/acs.est.5b02412
Citations Scopus - 155Web of Science - 135
2015 Biswas B, Sarkar B, Rusmin R, Naidu R, 'Bioremediation of PAHs and VOCs: Advances in clay mineral-microbial interaction', Environment International, 85 168-181 (2015) [C1]

Bioremediation is an effective strategy for cleaning up organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Advanced biore... [more]

Bioremediation is an effective strategy for cleaning up organic contaminants, such as polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs). Advanced bioremediation implies that biotic agents are more efficient in degrading the contaminants completely. Bioremediation by microbial degradation is often employed and to make this process efficient, natural and cost-effective materials can serve as supportive matrices. Clay/modified clay minerals are effective adsorbents of PAHs/VOCs, and readily available substrate and habitat for microorganisms in the natural soil and sediment. However, the mechanism underpinning clay-mediated biodegradation of organic compounds is often unclear, and this requires critical investigation. This review describes the role of clay/modified clay minerals in hydrocarbon bioremediation through interaction with microbial agents in specific scenarios. The vision is on a faster, more efficient and cost-effective bioremediation technique using clay-based products. This review also proposes future research directions in the field of clay modulated microbial degradation of hydrocarbons.

DOI 10.1016/j.envint.2015.09.017
Citations Scopus - 112Web of Science - 93
Co-authors Bhaba Biswas
2015 Sarkar B, Liu E, McClure S, Sundaramurthy J, Srinivasan M, Naidu R, 'Biomass derived palygorskite-carbon nanocomposites: Synthesis, characterisation and affinity to dye compounds', APPLIED CLAY SCIENCE, 114 617-626 (2015) [C1]
DOI 10.1016/j.clay.2015.07.001
Citations Scopus - 39Web of Science - 32
2015 Wu Y, Zeng S, Wang F, Megharaj M, Naidu R, Chen Z, 'Heterogeneous Fenton-like oxidation of malachite green by iron-based nanoparticles synthesized by tea extract as a catalyst', Separation and Purification Technology, 154 161-167 (2015) [C1]

The green synthesis of functional iron nanoparticles (Fe NPs) by tea extracts was used as a catalyst for the Fenton-like oxidation of malachite green (MG), where more than 85% of ... [more]

The green synthesis of functional iron nanoparticles (Fe NPs) by tea extracts was used as a catalyst for the Fenton-like oxidation of malachite green (MG), where more than 85% of MG was removed. The new findings are that the removal of MG by Fe NPs was based on the adsorption of MG onto iron oxide and degradation of MG by iron nanoparticles. This was confirmed by adsorption and degradation kinetics, indicating that: firstly, the adsorption kinetics follows the pseudo-first-order model; and secondly, degradation kinetics fitted well to the pseudo-second-order model. Morphology, size and changes in the Fe NPs surface were characterized using SEM, XRD, and FTIR techniques, showing that Fe<inf>2</inf>O<inf>3</inf> and Fe<inf>3</inf>O<inf>4</inf> was formed and green tea extract contained a high concentration of caffeine/polyphenols. It acted as both reducing and capping agents in the synthesis of Fe NPs. To further confirm the removal mechanism of MG by the functional Fe NPs, the degraded products were identified by FTIR and GC-MS analysis. Finally the mechanism of Fenton-like oxidation of MG based on both adsorption and degradation was proposed.

DOI 10.1016/j.seppur.2015.09.022
Citations Scopus - 82Web of Science - 60
Co-authors Megh Mallavarapu
2015 Naidu R, Wong MH, Nathanail P, 'Bioavailability the underlying basis for risk-based land management', Environmental Science and Pollution Research, 22 8775-8778 (2015) [C3]
DOI 10.1007/s11356-015-4295-z
Citations Scopus - 16Web of Science - 14
2015 Nguyen TC, Loganathan P, Nguyen TV, Pham TTN, Kandasamy J, Wu M, et al., 'Trace elements in road-deposited and waterbed sediments in Kogarah Bay, Sydney: enrichment, sources and fractionation', SOIL RESEARCH, 53 401-411 (2015) [C1]
DOI 10.1071/SR14163
Citations Scopus - 3Web of Science - 2
2015 Venkidusamy K, Megharaj M, Schröder U, Karouta F, Mohan SV, Naidu R, 'Electron transport through electrically conductive nanofilaments in Rhodopseudomonas palustris strain RP2', RSC Advances, 5 100790-100798 (2015) [C1]

Electronic dialogue between proteins is expected to be a key component of charge transport at the microbe-mineral interface (MMI) and requires complex structures. Microbial nanofi... [more]

Electronic dialogue between proteins is expected to be a key component of charge transport at the microbe-mineral interface (MMI) and requires complex structures. Microbial nanofilaments are one such structure produced in energetically engineered environments. These nanostructures consist of natural protein electronic conduits which can target the microbe-mineral interface and facilitate charge transport over a distance. Nanofilaments are phylogenetically diverse inducible extracellular appendages, and have the potential to serve as organic electronic conductors. However, recent investigations on such microbial nanofilaments have been confined to a few bacterial genera such as Geobacter, Shewanella and Synechocystis. Here, we report the evidence for longitudinal electron transport through inducible nanofilaments produced by another genus, the metabolically versatile photosynthetic, iron(iii) respiring bacterium Rhodopseudomonas palustris strain RP2, in photic, iron(iii) oxide-rich environments. In contrast, chemosynthetic dark-grown anoxic cells are weak in their ability to reduce ferric-oxide and no longer produce extracellular structures. Independent evaluation techniques illustrate the induction of extracellular filaments and their electrical properties. Scanning probe and nanofabricated electrode measurements provide conclusive evidence for the occurrence of direct charge transfer along the length and radius of nanofilaments from strain RP2. These findings not only expand our knowledge of the range of bacteria known to produce nanofilaments but also provide further research opportunities in the field of bionanotechnology, sustainable remediation (bioelectrochemical remediation systems) in contaminated sites (petroleum hydrocarbons) and MMI process at photic environments.

DOI 10.1039/c5ra08742b
Citations Scopus - 39Web of Science - 36
Co-authors Megh Mallavarapu
2015 Kuppusamy S, Thavamani P, Megharaj M, Naidu R, 'Bioremediation potential of natural polyphenol rich green wastes: A review of current research and recommendations for future directions', Environmental Technology and Innovation, 4 17-28 (2015) [C1]

&apos;Green waste&apos; (food, agro-industrial and forest residues) is a renowned valuable resource of polyphenols. Natural polyphenols are relatively efficient in the clean-up of... [more]

'Green waste' (food, agro-industrial and forest residues) is a renowned valuable resource of polyphenols. Natural polyphenols are relatively efficient in the clean-up of environmental pollutants based on their unique traits of chelation, adsorption, reduction, complexation, nutrient cycling, antibacterial effects and plant growth promotion. These significant traits have found emerging applications in the removal of heavy metals, pathogenic bacteria and dyes from contaminated soil and water through existing bioremedial techniques such as biosorption, phytoextraction and coagulation. Increasingly, polyphenol-rich natural extracts harnessed for green nanoparticle synthesis (production of particles between 1 and 100 nm in size using biological entities such as microorganisms or plant biomass) have found promising use as a remedial agent in the detoxification of toxic pollutants. However, current bioremediation approaches do not sufficiently exploit natural polyphenols, which are abundantly available and are non-toxic. This review examines the extent of natural polyphenol availability in green waste, and provides a critical view on the existing remedial options, knowledge gaps and hence scope for future research. It highlights the use of natural polyphenol-rich green wastes as nanofertilizers, bioamendments, biofilters and bacteriostats. Field application strategies such as microbe-assisted phytoremediation, bioaugmention and biostimulation are also emphasized, showing the multifunctional biotechnological potentials offered by natural polyphenols.

DOI 10.1016/j.eti.2015.04.001
Citations Scopus - 64Web of Science - 53
Co-authors Thava Palanisami, Megh Mallavarapu
2015 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Toxicity and oxidative stress induced by used and unused motor oil on freshwater microalga, Pseudokirchneriella subcapitata', ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 22 8890-8901 (2015) [C1]
DOI 10.1007/s11356-014-3403-9
Citations Scopus - 29Web of Science - 23
Co-authors Megh Mallavarapu, Kavitha Ramadass
2015 Thavamani P, Smith E, Kavitha R, Mathieson G, Megharaj M, Srivastava P, Naidu R, 'Risk based land management requires focus beyond the target contaminants-A case study involving weathered hydrocarbon contaminated soils', Environmental Technology and Innovation, 4 98-109 (2015) [C1]

Irrespective of the nature of contamination, the use of total contaminant loading as a measure of risk together with conservative policy guidance is proving major stumbling block ... [more]

Irrespective of the nature of contamination, the use of total contaminant loading as a measure of risk together with conservative policy guidance is proving major stumbling block towards remediation of contaminated sites. The objective of this study was to investigate the use of risk based approach to manage contaminated sites at field scale. This study recognizes the presence of weathered hydrocarbon compounds in long-term total petroleum hydrocarbon (TPH) contaminated soils and that such compounds may not pose risk to local receptors. A multispecies ecotoxicological assessment was used to determine the potential risk from weathered hydrocarbons to the surrounding environment. The ecotoxicity of soil residual TPHs was evaluated using earthworm, water-flea, two native and two non-native Australian plants, and soil microbial activity. Plant germination was 100% in all soils but post germination, seedlings except Ryegrass failed to establish. Earthworm toxicity studies found that there was a negative impact on earthworm reproduction and mortality. Further investigation of the poor plant growth and earthworm mortality revealed that it was due to the elevated salinity that developed due to surface evaporation of the saturated calcium sulphate and not residual soil TPHs. Toxicity assessment of the soil leachate on the aquatic environment showed no effect on the survival of water-flea even though the TPH concentrations in the first year leachate were as high as 1.6 mg TPH L-1. The study concluded that the residual TPHs in soils had little impact on a range of environmental receptors. Assessment of the residual TPH ecotoxicity was complicated by the elevated salinity of stockpile soils which impacted on the earthworm and phytotoxicity assessments. Therefore results of this study suggest that it is paramount to focus beyond target contaminants while implementing risk-based management approach. Indicators for risk based assessment are considered critical for regulatory decision making. The results of this study provide a valuable input in to the risk based management of contaminated sites.

DOI 10.1016/j.eti.2015.04.005
Citations Scopus - 25Web of Science - 19
Co-authors Megh Mallavarapu, Thava Palanisami
2015 Azizur Rahman M, Hogan B, Duncan E, Doyle C, Rahman MM, Nguyen TV, et al., 'Ecotoxicological Effects of an Arsenic Remediation Method on Three Freshwater Organisms - Lemna disperma, Chlorella sp. CE-35 and Ceriodaphnia cf. dubia', Water, Air, and Soil Pollution, 226 1-10 (2015) [C1]

Chemical methods have been used for the remediation of arsenic (As)-contaminated water; however, ecological consequences of these methods have not been properly addressed. The pre... [more]

Chemical methods have been used for the remediation of arsenic (As)-contaminated water; however, ecological consequences of these methods have not been properly addressed. The present study evaluated the effects of the Fe-oxide-coated sand (IOCS) remediation method on As toxicity to freshwater organisms (Lemna disperma, Chlorella sp. CE-35, and Ceriodaphnia cf. dubia). The As removal efficiency by IOCS decreased substantially with time. The IOCS remediation method was less effective at suppressing the toxicity of AsV than AsIII to L. disperma but was highly effective in reducing both the AsIII and AsV toxicity to C. cf. dubia. The growth of Chlorella sp. was significantly higher (p < 0.05) in remediated and pre-remediated water than in controls (non-As-contaminated filtered Colo River water) for AsIII, while the opposite was observed for AsV, indicating that AsV is more toxic than AsIII to this microalga. Although the IOCS can efficiently remove As from contaminated water, residual As and other constituents (e.g. Fe, nitrate) in the remediated water had a significant effect on freshwater organisms.

DOI 10.1007/s11270-015-2668-z
Citations Scopus - 1Web of Science - 1
Co-authors Mahmud Rahman
2015 Naidu R, Channey R, McConnell S, Johnston N, Semple KT, McGrath S, et al., 'Towards bioavailability-based soil criteria: past, present and future perspectives', Environmental Science and Pollution Research, 22 8779-8785 (2015)

Bioavailability has been used as a key indicator in chemical risk assessment yet poorly quantified risk factor. Worldwide, the framework used to assess potentially contaminated si... [more]

Bioavailability has been used as a key indicator in chemical risk assessment yet poorly quantified risk factor. Worldwide, the framework used to assess potentially contaminated sites is similar, and the decisions are based on threshold contaminant concentration. The uncertainty in the definition and measurement of bioavailability had limited its application to environment risk assessment and remediation. Last ten years have seen major developments in bioavailability research and acceptance. The use of bioavailability in the decision making process as one of the key variables has led to a gradual shift towards a more sophisticated risk-based approach. Now a days, many decision makers and regulatory organisations ¿more readily accept¿ this concept. Bioavailability should be the underlying basis for risk assessment and setting remediation goals of those contaminated sites that pose risk to environmental and human health. This paper summarises the potential application of contaminant bioavailability and bioaccessibility to the assessment of sites affected by different contaminants, and the potential for this to be the underlying basis for sustainable risk assessment and remediation in Europe, North America and Australia over the coming decade.

DOI 10.1007/s11356-013-1617-x
Citations Scopus - 19
Co-authors Thava Palanisami
2015 Duan L, Naidu R, Liu Y, Palanisami T, Dong Z, Mallavarapu M, Semple KT, 'Effect of ageing on benzo[a]pyrene extractability in contrasting soils', Journal of Hazardous Materials, 296 175-184 (2015) [C1]
DOI 10.1016/j.jhazmat.2015.04.050
Citations Scopus - 36Web of Science - 33
Co-authors Thava Palanisami, Yanju Liu, Megh Mallavarapu
2015 Huang L, Luo F, Chen Z, Megharaj M, Naidu R, 'Green synthesized conditions impacting on the reactivity of Fe NPs for the degradation of malachite green', SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, 137 154-159 (2015)
DOI 10.1016/j.saa.2014.08.116
Citations Scopus - 97Web of Science - 71
Co-authors Megh Mallavarapu
2015 Luo F, Yang D, Chen Z, Megharaj M, Naidu R, 'The mechanism for degrading Orange II based on adsorption and reduction by ion-based nanoparticles synthesized by grape leaf extract', Journal of Hazardous Materials, 296 37-45 (2015) [C1]
DOI 10.1016/j.jhazmat.2015.04.027
Citations Scopus - 68Web of Science - 53
Co-authors Megh Mallavarapu
2015 Kuang Y, Du J, Zhou R, Chen Z, Megharaj M, Naidu R, 'Calcium alginate encapsulated Ni/Fe nanoparticles beads for simultaneous removal of Cu (II) and monochlorobenzene', Journal of Colloid and Interface Science, 447 85-91 (2015) [C1]
DOI 10.1016/j.jcis.2015.01.080
Citations Scopus - 73Web of Science - 53
Co-authors Megh Mallavarapu
2015 Li R, Gao Y, Jin X, Chen Z, Megharaj M, Naidu R, 'Fenton-like oxidation of 2,4-DCP in aqueous solution using iron-based nanoparticles as the heterogeneous catalyst', Journal of Colloid and Interface Science, 438 87-93 (2015) [C1]
DOI 10.1016/j.jcis.2014.09.082
Citations Scopus - 100Web of Science - 80
Co-authors Megh Mallavarapu
2015 Li R, Jin X, Megharaj M, Naidu R, Chen Z, 'Heterogeneous Fenton oxidation of 2,4-dichlorophenol using iron-based nanoparticles and persulfate system', Chemical Engineering Journal, 264 587-594 (2015) [C1]
DOI 10.1016/j.cej.2014.11.128
Citations Scopus - 265Web of Science - 225
Co-authors Megh Mallavarapu
2015 Ramadass K, Megharaj M, Venkateswarlu K, Naidu R, 'Ecological implications of motor oil pollution: Earthworm survival and soil health', Soil Biology and Biochemistry, 85 72-81 (2015) [C1]
DOI 10.1016/j.soilbio.2015.02.026
Citations Scopus - 88Web of Science - 69
Co-authors Megh Mallavarapu, Kavitha Ramadass
2015 Rahman MM, Dong Z, Naidu R, 'Concentrations of arsenic and other elements in groundwater of Bangladesh and West Bengal, India: Potential cancer risk', Chemosphere, 139 54-64 (2015) [C1]
DOI 10.1016/j.chemosphere.2015.05.051
Citations Scopus - 98Web of Science - 81
Co-authors Mahmud Rahman
2015 Jiang C, Xu X, Megharaj M, Naidu R, Chen Z, 'Inhibition or promotion of biodegradation of nitrate by Paracoccus sp. in the presence of nanoscale zero-valent iron', Science of the Total Environment, 530-531 241-246 (2015) [C1]
DOI 10.1016/j.scitotenv.2015.05.044
Citations Scopus - 52Web of Science - 34
Co-authors Megh Mallavarapu
2015 Rusmin R, Sarkar B, Liu Y, McClure S, Naidu R, 'Structural evolution of chitosan-palygorskite composites and removal of aqueous lead by composite beads', Applied Surface Science, 353 363-375 (2015)
DOI 10.1016/j.apsusc.2015.06.124
Citations Scopus - 83Web of Science - 67
Co-authors Yanju Liu
2015 Donner E, Scheckel K, Sekine R, Popelka-Filcoff RS, Bennett JW, Brunetti G, et al., 'Non-labile silver species in biosolids remain stable throughout 50 years of weathering and ageing', Environmental Pollution, 205 78-86 (2015) [C1]
DOI 10.1016/j.envpol.2015.05.017
Citations Scopus - 38Web of Science - 37
2015 Abbasian F, Lockington R, Mallavarapu M, Naidu R, 'A Comprehensive Review of Aliphatic Hydrocarbon Biodegradation by Bacteria', Applied Biochemistry and Biotechnology, 176 670-699 (2015)
DOI 10.1007/s12010-015-1603-5
Citations Scopus - 288Web of Science - 193
Co-authors Megh Mallavarapu
2015 Biswas B, Sarkar B, Mandal A, Naidu R, 'Heavy metal-immobilizing organoclay facilitates polycyclic aromatic hydrocarbon biodegradation in mixed-contaminated soil', Journal of Hazardous Materials, 298 129-137 (2015) [C1]
DOI 10.1016/j.jhazmat.2015.05.009
Citations Scopus - 59Web of Science - 49
Co-authors Bhaba Biswas
2015 Sanderson P, Naidu R, Bolan N, Lim JE, Ok YS, 'Chemical stabilisation of lead in shooting range soils with phosphate and magnesium oxide: Synchrotron investigation', Journal of Hazardous Materials, 299 395-403 (2015) [C1]
DOI 10.1016/j.jhazmat.2015.06.056
Citations Scopus - 57Web of Science - 46
Co-authors Nanthi Bolan
2015 Zhuang Z, Wang F, Naidu R, Chen Z, 'Biosynthesis of Pd-Au alloys on carbon fiber paper: Towards an eco-friendly solution for catalysts fabrication', Journal of Power Sources, 291 132-137 (2015)
DOI 10.1016/j.jpowsour.2015.05.023
Citations Scopus - 39Web of Science - 22
2015 Subramaniyam V, Subashchandrabose SR, Thavamani P, Megharaj M, Chen Z, Naidu R, 'Chlorococcum sp. MM11 a novel phyco-nanofactory for the synthesis of iron nanoparticles', Journal of Applied Phycology, 27 1861-1869 (2015)
DOI 10.1007/s10811-014-0492-2
Citations Scopus - 115Web of Science - 57
Co-authors Megh Mallavarapu, Thava Palanisami, Suresh Subashchandrabose
2015 Sanderson P, Naidu R, Bolan N, 'Effectiveness of chemical amendments for stabilisation of lead and antimony in risk-based land management of soils of shooting ranges', Environmental Science and Pollution Research, 22 8942-8956 (2015)
DOI 10.1007/s11356-013-1918-0
Citations Scopus - 44
Co-authors Nanthi Bolan
2015 Krishnamurti GSR, Subashchandrabose SR, Megharaj M, Naidu R, 'Assessment of bioavailability of heavy metal pollutants using soil isolates of Chlorella sp.', Environmental Science and Pollution Research, 22 8826-8832 (2015)
DOI 10.1007/s11356-013-1799-2
Citations Scopus - 16Web of Science - 14
Co-authors Suresh Subashchandrabose, Megh Mallavarapu
2015 Thangarajan R, Bolan NS, Naidu R, Surapaneni A, 'Effects of temperature and amendments on nitrogen mineralization in selected Australian soils', Environmental Science and Pollution Research, 22 8843-8854 (2015)
DOI 10.1007/s11356-013-2191-y
Citations Scopus - 35Web of Science - 27
Co-authors Nanthi Bolan
2015 Duan L, Naidu R, Thavamani P, Meaklim J, Megharaj M, 'Managing long-term polycyclic aromatic hydrocarbon contaminated soils: a risk-based approach', Environmental Science and Pollution Research, 22 8927-8941 (2015)
DOI 10.1007/s11356-013-2270-0
Citations Scopus - 102Web of Science - 71
Co-authors Thava Palanisami, Megh Mallavarapu
2015 Das P, Megharaj M, Naidu R, 'Perfluorooctane sulfonate release pattern from soils of fire training areas in Australia and its bioaccumulation potential in the earthworm Eisenia fetida', Environmental Science and Pollution Research, 22 8902-8910 (2015)
DOI 10.1007/s11356-013-1782-y
Citations Scopus - 25Web of Science - 23
Co-authors Megh Mallavarapu
2015 Thavamani P, Megharaj M, Naidu R, 'Metal-tolerant PAH-degrading bacteria: development of suitable test medium and effect of cadmium and its availability on PAH biodegradation', Environmental Science and Pollution Research, 22 8957-8968 (2015)
DOI 10.1007/s11356-013-1850-3
Citations Scopus - 28Web of Science - 20
Co-authors Megh Mallavarapu, Thava Palanisami
2015 Subashchandrabose SR, Megharaj M, Venkateswarlu K, Naidu R, 'Interaction effects of polycyclic aromatic hydrocarbons and heavy metals on a soil microalga, Chlorococcum sp. MM11', Environmental Science and Pollution Research, 22 8876-8889 (2015)
DOI 10.1007/s11356-013-1679-9
Citations Scopus - 37Web of Science - 29
Co-authors Suresh Subashchandrabose, Megh Mallavarapu
2015 Smith E, Thavamani P, Ramadass K, Naidu R, Srivastava P, Megharaj M, 'Remediation trials for hydrocarbon-contaminated soils in arid environments: Evaluation of bioslurry and biopiling techniques', International Biodeterioration and Biodegradation, 101 56-65 (2015)
DOI 10.1016/j.ibiod.2015.03.029
Citations Scopus - 93Web of Science - 54
Co-authors Kavitha Ramadass, Megh Mallavarapu, Thava Palanisami
2015 Yirsaw BD, Megharaj M, Chen Z, Naidu R, 'Environmental application and ecological significance of nano-zero valent iron', Journal of Environmental Sciences (China), 44 88-98 (2015)
DOI 10.1016/j.jes.2015.07.016
Citations Scopus - 87Web of Science - 62
Co-authors Megh Mallavarapu
2015 Zheng X, Han B, Thavamani P, Duan L, Naidu R, 'Composition, source identification and ecological risk assessment of polycyclic aromatic hydrocarbons in surface sediments of the Subei Grand Canal, China', ENVIRONMENTAL EARTH SCIENCES, 74 2669-2677 (2015)
DOI 10.1007/s12665-015-4287-9
Citations Scopus - 13Web of Science - 12
Co-authors Thava Palanisami
2015 Lin J, Gan L, Chen Z, Naidu R, 'Biodegradation of tetradecane using Acinetobacter venetianus immobilized on bagasse', Biochemical Engineering Journal, 100 76-82 (2015) [C1]
DOI 10.1016/j.bej.2015.04.014
Citations Scopus - 36Web of Science - 31
2015 Nguyen TC, Loganathan P, Nguyen TV, Vigneswaran S, Kandasamy J, Naidu R, 'Simultaneous adsorption of Cd, Cr, Cu, Pb, and Zn by an iron-coated Australian zeolite in batch and fixed-bed column studies', Chemical Engineering Journal, 270 393-404 (2015) [C1]
DOI 10.1016/j.cej.2015.02.047
Citations Scopus - 235Web of Science - 202
2015 Ramadass K, Smith E, Palanisami T, Mathieson G, Srivastava P, Megharaj M, Naidu R, 'Evaluation of constraints in bioremediation of weathered hydrocarbon-contaminated arid soils through microcosm biopile study', International Journal of Environmental Science and Technology, 12 3597-3612 (2015)
DOI 10.1007/s13762-015-0793-2
Citations Scopus - 16Web of Science - 13
Co-authors Thava Palanisami, Kavitha Ramadass, Megh Mallavarapu
2015 Pal R, Megharaj M, Kirkbride KP, Naidu R, 'Adsorption and desorption characteristics of methamphetamine, 3,4-methylenedioxymethamphetamine, and pseudoephedrine in soils', Environmental science and pollution research international, 22 8855-8865 (2015)
DOI 10.1007/s11356-014-2940-6
Citations Scopus - 8Web of Science - 5
Co-authors Megh Mallavarapu
2015 Wijayawardena MAA, Naidu R, Megharaj M, Lamb D, Thavamani P, Kuchel T, 'Influence of ageing on lead bioavailability in soils: a swine study', Environmental science and pollution research international, 22 8979-8988 (2015) [C1]
DOI 10.1007/s11356-014-3577-1
Citations Scopus - 21Web of Science - 16
Co-authors Ayanka Wijayawardena, Megh Mallavarapu, Thava Palanisami
2015 Wijayawardena MAA, Naidu R, Megharaj M, Lamb D, Thavamani P, Kuchel T, 'Using soil properties to predict in vivo bioavailability of lead in soils', CHEMOSPHERE, 138 422-428 (2015) [C1]
DOI 10.1016/j.chemosphere.2015.06.073
Citations Scopus - 25Web of Science - 21
Co-authors Thava Palanisami, Ayanka Wijayawardena, Megh Mallavarapu
2015 Seshadri B, Bolan NS, Naidu R, 'Rhizosphere-induced heavy metal(Loid) transformation in relation to bioavailability and remediation', Journal of Soil Science and Plant Nutrition, 15 524-548 (2015) [C1]
Citations Scopus - 109Web of Science - 70
Co-authors Nanthi Bolan
2015 Fang C, Megharaj M, Naidu R, 'Chemical oxidization of some AFFFs leads to the formation of 6:2FTS and 8:2FTS', Environmental Toxicology and Chemistry, 34 2625-2628 (2015) [C1]

The present study tested some aqueous film-forming foam (AFFF) products for the presence of or the potential to form 1H,1H,2H,2H-perfluorooctanesulfonic acid (6:2FTS) and 1H,1H,2H... [more]

The present study tested some aqueous film-forming foam (AFFF) products for the presence of or the potential to form 1H,1H,2H,2H-perfluorooctanesulfonic acid (6:2FTS) and 1H,1H,2H,2H-perfluorodecane sulfonic acid (8:2FTS). The results demonstrated the appearance of significant levels of 6:2FTS and 8:2FTS after the oxidization of those AFFFs. The authors concluded that fluorotelomer skeletons exist but are derived from those formulations of AFFFs.

DOI 10.1002/etc.3115
Citations Scopus - 25Web of Science - 20
Co-authors Megh Mallavarapu, Cheng Fang
2015 Dong Z, Liu Y, Duan L, Bekele D, Naidu R, 'Uncertainties in human health risk assessment of environmental contaminants: A review and perspective', Environment International, 85 120-132 (2015) [C1]

Addressing uncertainties in human health risk assessment is a critical issue when evaluating the effects of contaminants on public health. A range of uncertainties exist through t... [more]

Addressing uncertainties in human health risk assessment is a critical issue when evaluating the effects of contaminants on public health. A range of uncertainties exist through the source-to-outcome continuum, including exposure assessment, hazard and risk characterisation. While various strategies have been applied to characterising uncertainty, classical approaches largely rely on how to maximise the available resources. Expert judgement, defaults and tools for characterising quantitative uncertainty attempt to fill the gap between data and regulation requirements. The experiences of researching 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) illustrated uncertainty sources and how to maximise available information to determine uncertainties, and thereby provide an 'adequate' protection to contaminant exposure. As regulatory requirements and recurring issues increase, the assessment of complex scenarios involving a large number of chemicals requires more sophisticated tools. Recent advances in exposure and toxicology science provide a large data set for environmental contaminants and public health. In particular, biomonitoring information, in vitro data streams and computational toxicology are the crucial factors in the NexGen risk assessment, as well as uncertainties minimisation. Although in this review we cannot yet predict how the exposure science and modern toxicology will develop in the long-term, current techniques from emerging science can be integrated to improve decision-making.

DOI 10.1016/j.envint.2015.09.008
Citations Scopus - 97Web of Science - 81
Co-authors Yanju Liu, Dawit Bekele
2015 Arias Espana VA, Mallavarapu M, Naidu R, 'Treatment technologies for aqueous perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA): A critical review with an emphasis on field testing', Environmental Technology &amp; Innovation, 4 168-181 (2015) [C1]
DOI 10.1016/j.eti.2015.06.001
Citations Scopus - 171Web of Science - 134
Co-authors Megh Mallavarapu
2015 Feng Y, Xiao B, Goerner K, Naidu R, 'The Influence of Catalyst and Temperature on Pine Sawdust Gasification Performance by an Externally Heated Gasifier', ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS, 37 1033-1038 (2015)
DOI 10.1080/15567036.2011.588678
Citations Scopus - 1Web of Science - 1
2015 Singh S, Thavamani P, Megharaj M, Naidu R, 'Multifarious activities of cellulose degrading bacteria from Koala (Phascolarctos cinereus) faeces.', Journal of animal science and technology, 57 23 (2015) [C1]
DOI 10.1186/s40781-015-0056-2
Co-authors Megh Mallavarapu, Thava Palanisami
2015 Nirola R, Megharaj M, Palanisami T, Aryal R, Venkateswarlu K, Ravi Naidu, 'Evaluation of metal uptake factors of native trees colonizing an abandoned copper mine a quest for phytostabilization', Journal of Sustainable Mining, 14 115-123 (2015)

Accumulation and enrichment of heavy metals in the above ground parts of Australian native Acacia pycnantha (Ap) and Eucalyptus camaldulensis (Ec) growing in an abandoned copper m... [more]

Accumulation and enrichment of heavy metals in the above ground parts of Australian native Acacia pycnantha (Ap) and Eucalyptus camaldulensis (Ec) growing in an abandoned copper mine located in Kapunda, South Australia have been studied. Cu and other metals (Na, Al, K, Ca, Fe, Zn, Cd and Pb) in plants and corresponding soils were analysed to evaluate plant interaction with soils containing heavy metals. As per the total metal analysis of leaf and corresponding soil samples, Ap accumulated 93.6 mg kg-1 of Cu in leaf while the corresponding soil concentration was 1632 mg kg-1. The Ec accumulated 5341 mg kg-1 of Cu in leaf while the concentration of this heavy metal in soil was 65 mg kg-1 in soil. The ESEM spectral analysis also showed a high leaf concentration of Cu in Ec (7%) as against only 0.12% in Ap. The average bioconcentration factor for Cu, Zn, Cd and Pb in Ec was much higher than that of Ap. Similarly, enrichment factor was more in Ec for Cu, Zn and Pb than in Ap. In contrast, translocation factor for only Zn and Cd was high in Ap. This study points out that Ec and Ap have different stabilising potential in remediating heavy metals like Cu in mined soils.

DOI 10.1016/j.jsm.2015.11.001
Citations Scopus - 69
Co-authors Thava Palanisami, Megh Mallavarapu
2015 Rajmohan M, Naidu RM, Thamaraiselvi D, Deepasree M, 'In vivo autofluorescence spectroscopic study and evaluation of DNA damage by comet assay in smokers', Journal of Clinical and Diagnostic Research, 9 ZC16-ZC19 (2015)

Context: Tobacco is known environmental factor to alter the chemical composition of cells and the structure of DNA. Cellular level changes of smoker¿s mucosa are assessed by autof... [more]

Context: Tobacco is known environmental factor to alter the chemical composition of cells and the structure of DNA. Cellular level changes of smoker¿s mucosa are assessed by autofluorescence spectroscopy and the DNA damage can be evaluated by single cell gel electrophoresis (comet assay). Aim: To substantiate the changes in the autofluorescence due to smoking with that of early DNA damage without any clinical change. Materials and Methods: Group I consists of 20 individuals with normal mucosa and Group II consists of 40 individuals with smoking habit. Only males were included in this study and their age ranging from 25 to 35 years. In vivo fluorescence spectra from both groups were obtained by using hand held fiber optic probe attached to Varian Cary Eclipse fluorescence spectrophotometer and comet assay was carried out for normal and smokers by their peripheral blood. Statistical Analysis Used: Independent-Samples t-test was used for statistical analysis. P-value was obtained to discriminate the statistical differences between the two groups. Results: The averaged excitation and emission spectra of normal and smoker¿s mucosa showed significant differences statistically. In comet assay, the mean tail length of smoker group was higher than the normal group. The results showed statistically significant differences (p = 0.05). Conclusion: These techniques will be very useful for monitoring of very early changes of mucosa before clinical manifestation of the lesion in high risk smokers and thus prevents the occurrence of premalignant disorders and early invasive carcinoma.

DOI 10.7860/JCDR/2015/13805.5874
Citations Scopus - 5
2015 Abbasian F, Lockington R, Megharaj M, Naidu R, 'The integration of sequencing and bioinformatics in metagenomics', REVIEWS IN ENVIRONMENTAL SCIENCE AND BIO-TECHNOLOGY, 14 357-383 (2015) [C1]
DOI 10.1007/s11157-015-9365-7
Citations Scopus - 9Web of Science - 9
Co-authors Megh Mallavarapu
2015 Shakoor MB, Niazi NK, Bibi I, Rahman MM, Naidu R, Dong Z, et al., 'Unraveling health risk and speciation of arsenic from groundwater in rural areas of Punjab, Pakistan', International Journal of Environmental Research and Public Health, 12 12371-12390 (2015) [C1]

This study determined the total and speciated arsenic (As) concentrations and other health-related water quality parameters for unraveling the health risk of As from drinking wate... [more]

This study determined the total and speciated arsenic (As) concentrations and other health-related water quality parameters for unraveling the health risk of As from drinking water to humans. Groundwater samples (n = 62) were collected from three previously unexplored rural areas (Chichawatni, Vehari, Rahim Yar Khan) of Punjab in Pakistan. The mean and median As concentrations in groundwater were 37.9 and 12.7 µg¿L-1 (range = 1.5¿201 µg¿L-1). Fifty three percent groundwater samples showed higher As value than WHO safe limit of 10 µg¿L-1. Speciation of As in groundwater samples (n = 13) showed the presence of inorganic As only; arsenite (As(III)) constituted 13%¿67% of total As and arsenate (As(V)) ranged from 33% to 100%. For As health risk assessment, the hazard quotient and cancer risk values were 11¿18 and 46¿600 times higher than the recommended values of US-EPA (i.e., 1.00 and 10-6, respectively). In addition to As, various water quality parameters (e.g., electrical conductivity, Na, Ca, Cl-, NO3-, SO42-, Fe, Mn, Pb) also enhanced the health risk. The results show that consumption of As-contaminated groundwater poses an emerging health threat to the communities in the study area, and hence needs urgent remedial and management measures.

DOI 10.3390/ijerph121012371
Citations Scopus - 151Web of Science - 124
Co-authors Mahmud Rahman
2015 Li S-W, Li J, Li H-B, Naidu R, Ma LQ, 'Arsenic bioaccessibility in contaminated soils: Coupling in vitro assays with sequential and HNO3 extraction', JOURNAL OF HAZARDOUS MATERIALS, 295 145-152 (2015) [C1]
DOI 10.1016/j.jhazmat.2015.04.011
Citations Scopus - 64Web of Science - 50
2015 Wang L, Yang D, Lamb D, Chen Z, Lesniewsk PJ, Mallavarapu M, Naidu R, 'Application of mathematical models and genetic algorithm to simulate the response characteristics of an ion selective electrode array for system recalibration', Chemometrics and Intelligent Laboratory Systems, 144 24-30 (2015) [C1]
DOI 10.1016/j.chemolab.2015.03.007
Citations Scopus - 10Web of Science - 7
Co-authors Megh Mallavarapu, Liang Wang
2015 Kader M, Lamb DT, Correll R, Megharaj M, Naidu R, 'Pore-water chemistry explains zinc phytotoxicity in soil', Ecotoxicology and Environmental Safety, 122 252-259 (2015) [C1]

Zinc (Zn) is a widespread soil contaminant arising from a numerous anthropogenic sources. However, adequately predicting toxicity of Zn to ecological receptors remains difficult d... [more]

Zinc (Zn) is a widespread soil contaminant arising from a numerous anthropogenic sources. However, adequately predicting toxicity of Zn to ecological receptors remains difficult due to the complexity of soil characteristics. In this study, we examined solid-solution partitioning using pore-water data and toxicity of Zn to cucumber (Cucumis sativus L.) in spiked soils. Pore-water effective concentration (ECx, x=10%, 20% and 50% reduction) values were negatively related to pH, indicating lower Zn pore water concentration were needed to cause phytotoxicity at high pH soils. Total dissolved zinc (Zn<inf>pw</inf>) and free zinc (Zn<sup>2+</sup>) in soil-pore water successfully described 78% and 80.3% of the variation in relative growth (%) in the full dataset. When the complete data set was used (10 soils), the estimated EC50<inf>pw</inf> was 450 and 79.2µM for Zn<inf>pw</inf> and Zn<sup>2+</sup>, respectively. Total added Zn, soil pore water pH (pH<inf>pw</inf>) and dissolve organic carbon (DOC) were the best predictors of Zn<inf>pw</inf> and Zn<sup>2+</sup> in pore-water. The EC10 (total loading) values ranged from 179 to 5214mg/kg, depending on soil type. Only pH measurements in soil were related to ECx total Zn data. The strongest relationship to ECx overall was pH<inf>ca</inf>, although pH<inf>w</inf> and pH<inf>pw</inf> were in general related to Zn ECx. Similarly, when a solution-only model was used to predict Zn in shoot, DOC was negatively related to Zn in shoot, indicating a reduction in uptake/ translocation of Zn from solution with increasing DOC.

DOI 10.1016/j.ecoenv.2015.08.004
Citations Scopus - 29Web of Science - 22
Co-authors Megh Mallavarapu
2015 Mukkata K, Kantachote D, Wittayaweerasak B, Techkarnjanaruk S, Mallavarapu M, Naidu R, 'Distribution of Mercury in Shrimp Ponds and Volatilization of Hg by Isolated Resistant Purple Nonsulfur Bacteria', WATER AIR AND SOIL POLLUTION, 226 (2015) [C1]
DOI 10.1007/s11270-015-2418-2
Citations Scopus - 13Web of Science - 11
Co-authors Megh Mallavarapu
2015 Yu B, Jin X, Kuang Y, Megharaj M, Naidu R, Chen Z, 'An integrated biodegradation and nano-oxidation used for the remediation of naphthalene from aqueous solution', CHEMOSPHERE, 141 205-211 (2015) [C1]
DOI 10.1016/j.chemosphere.2015.07.050
Citations Scopus - 19Web of Science - 15
Co-authors Megh Mallavarapu
2015 Poorvisha R, Suriyaraj SP, Thavamani P, Naidu R, Megharaj M, Bhattacharyya A, Selvakumar R, 'Synthesis and characterisation of 3-dimensional hydroxyapatite nanostructures using a thermoplastic polyurethane nanofiber sacrificial template', RSC Advances, 5 97773-97780 (2015) [C1]

In this study, we report a facile synthesis of shape controlled three dimensional hydroxyapatite nanostructures (HAp) using a sacrificial thermoplastic polyurethane (TPU) nanofibe... [more]

In this study, we report a facile synthesis of shape controlled three dimensional hydroxyapatite nanostructures (HAp) using a sacrificial thermoplastic polyurethane (TPU) nanofiber template. The TPU nanofibers synthesised using an electrospinning process were used as a template during the HAp synthesis through a precipitation process. Various HAp morphologies including distinctly placed cylindrically porous HAp architecture, coral reef like, tightly packed fibrous sheet like and nanofiber like were synthesised using the TPU nanofiber template. All the synthesised HAp were characterized using appropriate techniques like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) attached with selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The morphology, pore arrangement and the particle size of the HAp varied significantly with varying dimensions of the template and the template available per unit area of HAp. Hence, we have achieved four different 3D HAp morphologies using a single type of TPU nanofiber template. The TPU templated HAp nanostructures were more biodegradable than the control HAp.

DOI 10.1039/c5ra18593a
Citations Scopus - 10Web of Science - 7
Co-authors Megh Mallavarapu, Thava Palanisami
2015 Wang L, Liu E, Cheng Y, Bekele DN, Lamb D, Chen Z, et al., 'Novel methodologies for automatically and simultaneously determining BTEX components using FTIR spectra', Talanta, 144 1104-1110 (2015) [C1]

This study introduced a patented novel methodological system for automatically analysis of Fourier Transform Infrared Spectrometer (FTIR) spectrum data located at &apos;fingerprin... [more]

This study introduced a patented novel methodological system for automatically analysis of Fourier Transform Infrared Spectrometer (FTIR) spectrum data located at 'fingerprint' region (wavenumber 670-800 cm-1), to simultaneously determinate multiple petroleum hydrocarbons (PHs) in real mixture samples. This system includes: an object oriented baseline correction; Band decomposition (curve fitting) method with mathematical optimization; and Artificial Neural Network (ANN) for determination, which is suitable for the characteristics of this IR regions, where the spectra are normally with low signal to noise ratio and high density of peaks. BTEX components are potentially lethal carcinogens and contained in many petroleum products. As a case study, six BTEX components were determinate automatically and simultaneously in mixture vapor samples. The robustness of the BTEX determination was validated using real petroleum samples, and the prediction results were compared with gas chromatography-mass spectrometry (GC-MS).

DOI 10.1016/j.talanta.2015.07.044
Citations Scopus - 11Web of Science - 10
Co-authors Liang Wang, Megh Mallavarapu, Ying Cheng, Dawit Bekele
2015 Wang L, Yang D, Fang C, Chen Z, Lesniewski PJ, Mallavarapu M, Naidu R, 'Application of neural networks with novel independent component analysis methodologies to a Prussian blue modified glassy carbon electrode array', Talanta, 131 395-403 (2015) [C1]
DOI 10.1016/j.talanta.2014.08.010
Citations Scopus - 14Web of Science - 13
Co-authors Liang Wang, Cheng Fang, Megh Mallavarapu
2015 Abbasian F, Lockington R, Mallavarapu M, Naidu R, 'A pyrosequencing-based analysis of microbial diversity governed by ecological conditions in the Winogradsky column', WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY, 31 1115-1126 (2015) [C1]
DOI 10.1007/s11274-015-1861-y
Citations Scopus - 13Web of Science - 13
Co-authors Megh Mallavarapu
2015 Arias E VA, Mallavarapu M, Naidu R, 'Identification of the source of PFOS and PFOA contamination at a military air base site', Environmental Monitoring and Assessment, 187 4111-4111 (2015) [C1]
DOI 10.1007/s10661-014-4111-0
Citations Scopus - 35Web of Science - 23
Co-authors Megh Mallavarapu
2015 Lin J, Weng X, Jin X, Megharaj M, Naidu R, Chen Z, 'Reactivity of iron-based nanoparticles by green synthesis under various atmospheres and their removal mechanism of methylene blue', RSC ADVANCES, 5 70874-70882 (2015) [C1]
DOI 10.1039/c5ra10629j
Citations Scopus - 27Web of Science - 21
Co-authors Megh Mallavarapu
2014 Selvakumar R, Seethalakshmi N, Thavamani P, Naidu R, Megharaj M, 'Recent advances in the synthesis of inorganic nano/microstructures using microbial biotemplates and their applications', RSC ADVANCES, 4 52156-52169 (2014)
DOI 10.1039/c4ra07903e
Citations Scopus - 75Web of Science - 58
Co-authors Thava Palanisami, Megh Mallavarapu