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Li L, Guo Z, Deng R, Fan T, Dong D, Dai Y, Li C. The concentrations and behavior of classic phthalates and emerging phthalate alternatives in different environmental matrices and their biological health risks. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:46790-46805. [PMID: 38977546 DOI: 10.1007/s11356-024-34213-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 06/28/2024] [Indexed: 07/10/2024]
Abstract
Because of their excellent plasticity, phthalates or phthalic acid esters (PAEs) are widely used in plastic products. However, due to the recognized toxicity of PAEs and legislative requirements, the production and use of emerging PAE alternatives have rapidly grown, such as di-isononyl cyclohexane-1,2-dicarboxylate (DINCH) and di(2-ethylhexyl) terephthalate (DEHTP) which are the primary replacements for classic PAEs. Nowadays, PAEs and emerging PAE alternatives are frequently found in a variety of environmental media, including the atmosphere, sludge, rivers, and seawater/sediment. PAEs and emerging PAE alternatives are involved in endocrine-disrupting effects, and they affect the reproductive physiology of different species of fish and mammals. Therefore, their presence in the environment is of considerable concern due to their potential effects on ecosystem function and public health. Nevertheless, current research on the prevalence, destiny, and conduct of PAEs in the environment has primarily focused on classic PAEs, with little attention given to emerging PAE alternatives. The present article furnishes a synopsis of the physicochemical characteristics, occurrence, transport, fate, and adverse effects of both classic PAEs and emerging PAE alternatives on organisms in the ecosystem. Our analysis reveals that both classic PAEs and emerging PAE alternatives are widely distributed in all environmental media, with emerging PAE alternatives increasingly replacing classic PAEs. Various pathways can transform and degrade both classic PAEs and emerging PAE alternatives, and their own and related metabolites can have toxic effects on organisms. This research offers a more extensive comprehension of the health hazards associated with classic PAEs and emerging PAE alternatives.
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Affiliation(s)
- Lele Li
- School of Resources and Environmental Engineering, Hefei University of Technology, No. 193 Tunxi Road, Hefei, 230009, China
- Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, 230009, China
| | - Zhi Guo
- School of Resources and Environmental Engineering, Hefei University of Technology, No. 193 Tunxi Road, Hefei, 230009, China.
- Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, 230009, China.
| | - Rui Deng
- School of Resources and Environmental Engineering, Hefei University of Technology, No. 193 Tunxi Road, Hefei, 230009, China
- Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, 230009, China
| | - Ting Fan
- School of Resources and Environment, Anhui Agricultural University, Hefei, 230036, China
| | - Dazhuang Dong
- School of Resources and Environmental Engineering, Hefei University of Technology, No. 193 Tunxi Road, Hefei, 230009, China
- Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, 230009, China
| | - Yaodan Dai
- School of Resources and Environmental Engineering, Hefei University of Technology, No. 193 Tunxi Road, Hefei, 230009, China
- Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, 230009, China
| | - Chenxuan Li
- School of Resources and Environmental Engineering, Hefei University of Technology, No. 193 Tunxi Road, Hefei, 230009, China
- Anhui Engineering Research Center of Industrial Wastewater Treatment and Resource Recovery, Hefei University of Technology, Hefei, 230009, China
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Zhang Y, Gao Y, Xi B, Li Y, Ge X, Gong Y, Chen H, Chen J, Tan W, Yuan Y. Full life cycle and sustainability transitions of phthalates in landfill: A review. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 170:215-229. [PMID: 37717503 DOI: 10.1016/j.wasman.2023.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 08/26/2023] [Accepted: 09/12/2023] [Indexed: 09/19/2023]
Abstract
Phthalates (PAEs) are added to various products as a plasticizer. As these products age and are disposed of, plastic waste containing PAEs enters the landfill. The landfill environment is complicated and can be regarded as a "black box". Also, PAEs do not bind with the polymer matrix. Therefore, when a series of physical chemistry and biological reactions occur during the stabilization of landfills, PAEs leach from waste and migrate to the surrounding environmental media, thereby contaminating the surrounding soil, water ecosystems, and atmosphere. Although research on PAEs has achieved progress over the years, they are mainly concentrated on a particular aspect of PAEs in the landfill; there are fewer inquiries on the life cycle of PAEs. In this study, we review the presence of PAEs in the landfill in the following aspects: (1) the main source of PAEs in landfills; (2) the impact of the landfill environment on PAE migration and conversion; (3) distribution and transmedia migration of PAEs in aquatic ecosystems, soils, and atmosphere; and (4) PAE management and control in the landfill and future research direction. The purpose is to track the life cycle of PAEs in landfills, provide scientific basis for in-depth understanding of the migration and transformation of PAEs and environmental pollution control in landfills, and new ideas for the sustainable utilization of landfills.
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Affiliation(s)
- Yifan Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Yiman Gao
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Beidou Xi
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Yanjiao Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Xiaoyuan Ge
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Lan Zhou Jiao Tong University, Lanzhou 730070, China
| | - Yi Gong
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Beijing University of Chemical Technology, Beijing 100029, China
| | - Huiru Chen
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; North China University of Water Resources and Electric Power, Zheng Zhou 450046, China
| | - Jiabao Chen
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China
| | - Wenbing Tan
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Ying Yuan
- State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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3
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Wang F, Liu Y, Cao M, Zhou B, Chen H, Yuan R, Liu S, Xing B. Mechanisms of ZnO Nanoparticles Enhancing Phototransformation of Biologically Derived Organic Phosphorus in Aquatic Environments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:3691-3702. [PMID: 36821710 DOI: 10.1021/acs.est.3c00704] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Zinc oxide nanoparticles (ZnO NPs), as the highly efficient photocatalysts, could enhance the transformation of biogenic organic phosphorus (OP) to orthophosphate (PO43-) by photodegradation, accelerating eutrophication. Conversely, orthophosphate can also transform ZnO NPs and thus potentially alter their catalytic and chemical properties. Here, we investigated the transformation mechanisms of three biogenic OP compounds and ZnO NPs under ultraviolet light (UV) illumination: inositol phosphates (IHPs), nucleic acids (DNA), and aminoethylphosphonic acid (AEP). The physicochemical characteristics of the resulting products were systematically characterized. Results show that ZnO NPs accelerated the transformation of IHPs, DNA, and AEP to inorganic phosphorus with the direct photolysis efficiencies of 98.14, 87.68, and 51.76%, respectively. The main component of the precipitates remained ZnO NPs, and Zn3(PO4)2 was identified. Zinc phytate was determined in the ZnO NP-IHP system. 31P NMR and FTIR further confirmed that the aquatic phase contained orthophosphate. Photoproduced hydroxyl (·OH) and superoxide (·O2-) were proved to play a dominant role in the OP photomineralization. Furthermore, ZnO NPs significantly enhanced the intensity of ·OH and ·O2- compared to the OP and Zn2+ solution alone. This work explored the light-induced mineralization processes of OP with ZnO NPs indicating that nanophotocatalysts may play a positive role in transformation of OP species in aquatic environments to further contribute to eutrophication.
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Affiliation(s)
- Fei Wang
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875 Beijing, China
| | - Yuxin Liu
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875 Beijing, China
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Manman Cao
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875 Beijing, China
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Beihai Zhou
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Huilun Chen
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Rongfang Yuan
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Shuhu Liu
- Laboratory of Synchrotron Radiation, Institute of High Energy Physics, The Chinese Academy of Sciences, Beijing 100039, China
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, Massachusetts 01003, United States
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Trombino S, Sole R, Di Gioia ML, Procopio D, Curcio F, Cassano R. Green Chemistry Principles for Nano- and Micro-Sized Hydrogel Synthesis. Molecules 2023; 28:molecules28052107. [PMID: 36903352 PMCID: PMC10004334 DOI: 10.3390/molecules28052107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/26/2023] [Accepted: 01/26/2023] [Indexed: 03/06/2023] Open
Abstract
The growing demand for drug carriers and green-technology-based tissue engineering materials has enabled the fabrication of different types of micro- and nano-assemblies. Hydrogels are a type of material that have been extensively investigated in recent decades. Their physical and chemical properties, such as hydrophilicity, resemblance to living systems, swelling ability and modifiability, make them suitable to be exploited for many pharmaceutical and bioengineering applications. This review deals with a brief account of green-manufactured hydrogels, their characteristics, preparations, importance in the field of green biomedical technology and their future perspectives. Only hydrogels based on biopolymers, and primarily on polysaccharides, are considered. Particular attention is given to the processes of extracting such biopolymers from natural sources and the various emerging problems for their processing, such as solubility. Hydrogels are catalogued according to the main biopolymer on which they are based and, for each type, the chemical reactions and the processes that enable their assembly are identified. The economic and environmental sustainability of these processes are commented on. The possibility of large-scale processing in the production of the investigated hydrogels are framed in the context of an economy aimed at waste reduction and resource recycling.
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5
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Min N, Yao J, Li H, Chen Z, Pang W, Zhu J, Kümmel S, Schaefer T, Herrmann H, Richnow HH. Humic Substance Photosensitized Degradation of Phthalate Esters Characterized by 2H and 13C Isotope Fractionation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:1930-1939. [PMID: 36689325 PMCID: PMC9910037 DOI: 10.1021/acs.est.2c06783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 01/06/2023] [Accepted: 01/06/2023] [Indexed: 06/17/2023]
Abstract
The photosensitized transformation of organic chemicals is an important degradation mechanism in natural surface waters, aerosols, and water films on surfaces. Dissolved organic matter including humic-like substances (HS), acting as photosensitizers that participate in electron transfer reactions, can generate a variety of reactive species, such as OH radicals and excited triplet-state HS (3HS*), which promote the degradation of organic compounds. We use phthalate esters, which are important contaminants found in wastewaters, landfills, soils, rivers, lakes, groundwaters, and mine tailings. We use phthalate esters as probes to study the reactivity of HS irradiated with artificial sunlight. Phthalate esters with different side-chain lengths were used as probes for elucidation of reaction mechanisms using 2H and 13C isotope fractionation. Reference experiments with the artificial photosensitizers 4,5,6,7-tetrachloro-2',4',5',7'-tetraiodofluorescein (Rose Bengal), 3-methoxy-acetophenone (3-MAP), and 4-methoxybenzaldehyde (4-MBA) yielded characteristic fractionation factors (-4 ± 1, -4 ± 2, and -4 ± 1‰ for 2H; 0.7 ± 0.2, 1.0 ± 0.4, and 0.8 ± 0.2‰ for 13C), allowing interpretation of reaction mechanisms of humic substances with phthalate esters. The correlation of 2H and 13C fractions can be used diagnostically to determine photosensitized reactions in the environment and to differentiate among biodegradation, hydrolysis, and photosensitized HS reaction.
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Affiliation(s)
- Ning Min
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
- Department
of Isotope Biogeochemistry, Helmholtz Centre
for Environmental Research − UFZ, Permoserstraße 15, Leipzig 04318, Germany
| | - Jun Yao
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
| | - Hao Li
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
| | - Zhihui Chen
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
| | - Wancheng Pang
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
| | - Junjie Zhu
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
| | - Steffen Kümmel
- Department
of Isotope Biogeochemistry, Helmholtz Centre
for Environmental Research − UFZ, Permoserstraße 15, Leipzig 04318, Germany
| | - Thomas Schaefer
- Atmospheric
Chemistry Department (ACD), Leibniz Institute
for Tropospheric Research (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany
| | - Hartmut Herrmann
- Atmospheric
Chemistry Department (ACD), Leibniz Institute
for Tropospheric Research (TROPOS), Permoserstraße 15, 04318 Leipzig, Germany
| | - Hans Hermann Richnow
- School
of Water Resources and Environment and Research Center of Environmental
Science and Engineering, Sino-Hungarian Joint Laboratory of Environmental
Science and Health, China University of
Geosciences (Beijing), 29 Xueyuan Road, Haidian District, 100083 Beijing, China
- Department
of Isotope Biogeochemistry, Helmholtz Centre
for Environmental Research − UFZ, Permoserstraße 15, Leipzig 04318, Germany
- Isodetect
Leipzig GmbH, Deutscher
Platz 5b, Leipzig 04103, Germany
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Min N, Yao J, Amde M, Li H, Pang W, Zhu J, Cao Y, Richnow HH. Compound-specific isotopic analysis to characterize the photocatalytic reaction of TiO 2 nanoparticles with diethyl phthalate. CHEMOSPHERE 2022; 307:135892. [PMID: 35987264 DOI: 10.1016/j.chemosphere.2022.135892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 07/07/2022] [Accepted: 07/28/2022] [Indexed: 06/15/2023]
Abstract
In this study compound-specific isotope analysis (CSIA) has been used to explore the degradation mechanism of nano titanium dioxide (TiO2) catalyzes photodegradation of diethyl phthalate (DEP). TiO2 is a popular photosensitizer with potential in waste water treatment and application in advanced oxidation processes. The degradation process of DEP can be described with a first-order kinetics in the applied concentration ranges. The larger degradation rate constant has been found at neutral conditions. The 13C and 2H isotope fractionation associated with the nano TiO2 catalyzes photodegradation of DEP at pH 3, 7 and 11 yield normal isotope effects. In the TiO2/UV/DEP and TiO2/H2O2/UV/DEP systems, the correlation of 13C and 2H fractionation (Λ) were calculated to be 2.7 ± 0.2, 2.8 ± 0.2 at pH 3, 2.2 ± 0.4, 2.5 ± 0.2, 2.3 ± 0.6 at pH 7 and 2.6 ± 0.3, 2.2 ± 0.3, 2.7 ± 0.2 and 2.3 ± 0.3 at pH11, respectively. The dominant free radical species in studied systems were explored by combining free radical quenching method and electron paramagnetic resonance analysis. The hydroxyl radicals have been found as the main radical species at all pH conditions studied. Furthermore, the 13C and 2H fractionation suggested that the addition of •OH on the benzene ring of DEP is the main conversion pathway. Therefore, CSIA is a promising technology for the identification of reaction pathways of DEP for example in water treatment systems.
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Affiliation(s)
- Ning Min
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China; Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research, UFZ, Permoserstraße 15, 04318 Leipzig, Germany.
| | - Jun Yao
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Meseret Amde
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China; Department of Chemistry, College of Natural and Computational Sciences, Haramaya University, Oromia, Ethiopia.
| | - Hao Li
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Wancheng Pang
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Junjie Zhu
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Ying Cao
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China.
| | - Hans Hermann Richnow
- School of Water Resource and Environment, Research Center of Environmental Science and Engineering, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), 29 Xueyuan Road, Haidian District, Beijing, 100083, China; Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research, UFZ, Permoserstraße 15, 04318 Leipzig, Germany; Isodetect GmbH, Deutscher Platz 5b, 04103, Leipzig, Germany.
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7
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Mondal T, Mondal S, Ghosh SK, Pal P, Soren T, Pandey S, Maiti TK. Phthalates - A family of plasticizers, their health risks, phytotoxic effects, and microbial bioaugmentation approaches. ENVIRONMENTAL RESEARCH 2022; 214:114059. [PMID: 35961545 DOI: 10.1016/j.envres.2022.114059] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 07/18/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Phthalates are a family of reprotoxicant compounds, predominantly used as a plasticizer to improve the flexibility and longevity of consumable plastic goods. After their use these plastic products find their way to the waste disposal sites where they leach out the hazardous phthalates present within them, into the surrounding environment, contaminating soil, groundwater resources, and the nearby water bodies. Subsequently, phthalates move into the living system through the food chain and exhibit the well-known phenomenon of biological magnification. Phthalates as a primary pollutant have been classified as 1B reprotoxicants and teratogens by different government authorities and they have thus imposed restrictions on their use. Nevertheless, the release of these compounds in the environment is unabated. Bioremediation has been suggested as one of the ways of mitigating this menace, but studies regarding the field applications of phthalate utilizing microbes for this purpose are limited. Through this review, we endeavor to make a deeper understanding of the cause and concern of the problem and to find out a possible solution to it. The review critically emphasizes the various aspects of phthalates toxicity, including their chemical nature, human health risks, phytoaccumulation and entry into the food chain, microbial role in phthalate degradation processes, and future challenges.
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Affiliation(s)
- Tanushree Mondal
- Microbiology Laboratory, Department of Botany, The University of Burdwan, Golapbag, Purba Bardhaman, P. O. -Rajbati, 713104, West Bengal, India.
| | - Sayanta Mondal
- Microbiology Laboratory, Department of Botany, The University of Burdwan, Golapbag, Purba Bardhaman, P. O. -Rajbati, 713104, West Bengal, India.
| | - Sudip Kumar Ghosh
- Microbiology Laboratory, Department of Botany, The University of Burdwan, Golapbag, Purba Bardhaman, P. O. -Rajbati, 713104, West Bengal, India.
| | - Priyanka Pal
- Microbiology Laboratory, Department of Botany, The University of Burdwan, Golapbag, Purba Bardhaman, P. O. -Rajbati, 713104, West Bengal, India.
| | - Tithi Soren
- Microbiology Laboratory, Department of Botany, The University of Burdwan, Golapbag, Purba Bardhaman, P. O. -Rajbati, 713104, West Bengal, India.
| | - Sanjeev Pandey
- Department of Botany, Banwarilal Bhalotia College, Asansol, 713303, West Bengal, India.
| | - Tushar Kanti Maiti
- Microbiology Laboratory, Department of Botany, The University of Burdwan, Golapbag, Purba Bardhaman, P. O. -Rajbati, 713104, West Bengal, India.
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8
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Feng JR, Ni HG. A 2D CSIA-based math method to quantify degradation rate by C-H bond breaking. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2022; 44:2835-2842. [PMID: 34309790 DOI: 10.1007/s10653-021-01045-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 07/19/2021] [Indexed: 06/13/2023]
Abstract
Compound-specific isotope analysis has been demonstrated to be a powerful tool for the assessment of in situ pollutant degradation. Enrichment factor, an essential and prerequisite parameter, could be determined under simulated control laboratory in advance. However, different microbial community composition and substrate availability may significantly affect the accuracy of simulated enrichment factor. Here, a modified mathematic method of two dimensional is proposed to quantify the extent of pollutant degradation involving the break of carbon and hydrogen bond. In this new model, the laboratory cultures used to determine carbon or hydrogen enrichment factors in advance could be canceled and the key point to assess the extent of biodegradation is only determining the value of Λri (dual C-H isotope slope calculated with a self-modified model) in the field investigation. As a new and convenient method, this math model greatly facilitates the investigation of pollutant degradation extent under field conditions. Two approaches are applied to evaluate the proposed model. With our model, the estimated results based on C isotope are consistent with those measured values, while those based on H isotope are unsatisfactory. This can be attributed to the differences in accuracy of C-H isotope determinations. Overall, enrichment factors and biodegradation rates calculated with the proposed model are comparable with those measured figures.
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Affiliation(s)
- Jin-Ru Feng
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China
| | - Hong-Gang Ni
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China.
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9
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Feng JR, Deng QX, Ni HG. Photodegradation of phthalic acid esters under simulated sunlight: Mechanism, kinetics, and toxicity change. CHEMOSPHERE 2022; 299:134475. [PMID: 35381265 DOI: 10.1016/j.chemosphere.2022.134475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 03/26/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
The photodegradation of two phthalic acid esters (PAEs), dimethyl phthalate (DMP) and di-n-octyl phthalate (DOP), under simulated sunlight in aqueous or organic phases (n-hexane (HEX) and dichloromethane (DCM)) was investigated. The mean photodegradation rates were ranked by half-lives as follows: DOP in DCM (3.77 h) < DMP in DCM (9.62 h) < DOP in H2O (3.99 days) < DMP in H2O (19.2 days) < DOP in HEX (21.0 days) < DMP in HEX (>30 days). Compound-specific stable isotope analysis (CSIA) combined with intermediate analysis was employed to explore the involved initial photoreaction mechanism. C-O bond cleavage, chlorine radical adduction to the aromatic ring, competing reactions of chlorine radical adduction to the aromatic ring and side chain, and a singlet oxygen-mediated pathway were mainly responsible for initial photodegradation mechanism of PAEs in H2O, DMP in DCM, DOP in DCM, and DOP in HEX, respectively. Furthermore, distinct isotope fractionation patterns of PAEs photodegradation open the possibility of using CSIA to differentiate the involved solvents in the field. More toxic and recalcitrant intermediates emerged during the photodegradation of DMP in DCM, while the risk to human health was reduced during the photochemical transformation of DOP in organic solvents.
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Affiliation(s)
- Jin-Ru Feng
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China
| | - Qing-Xin Deng
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China
| | - Hong-Gang Ni
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China.
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10
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Huang Y, Ren W, Liu H, Wang H, Xu Y, Han Y, Teng Y. Contrasting impacts of drying-rewetting cycles on the dissipation of di-(2-ethylhexyl) phthalate in two typical agricultural soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 792:148433. [PMID: 34146807 DOI: 10.1016/j.scitotenv.2021.148433] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/09/2021] [Accepted: 06/09/2021] [Indexed: 06/12/2023]
Abstract
Di-(2-ethylhexyl) phthalate (DEHP) pollution has become a growing problem in farmlands of China. Drying-rewetting (DW) cycle is one of frequent environmental changes that agricultural production is confronted with, and also a convenient and practical agronomic regulation measure. In this study, in order to explore the effects of DW cycles on the dissipation of DEHP and their driving mechanisms in different types of soils, we performed a 45-day microcosm culture experiment with two typical agricultural soils, Lou soil (LS) and Red soil (RS). High-throughput sequencing was applied to study the response of soil microbial communities in the process of DEHP dissipation under DW cycles. The results showed that the DW cycles considerably inhibited the dissipation of DEHP in LS while promoted that in RS. The DW cycles obviously decreased the diversity, the relative abundance of significantly differential bacteria, and the total abundance of potential degrading bacterial groups in LS, whereas have little effect on bacterial community in RS, except at the initial cultivation stage when the corresponding parameters were promoted. The inhibition of the DW cycles on DEHP dissipation in LS was mainly derived from microbial degradation, but the interplay between microbial functions and soil attributes contributed to the promotion of DEHP dissipation in RS under the DW cycles. This comprehensive understanding of the contrasting impacts and underlying driving mechanisms may provide crucial implications for the prevention and control of DEHP pollution in regional soils.
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Affiliation(s)
- Yiwen Huang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; School of Environment and Safety Engineering, Changzhou University, Changzhou 213164, China
| | - Wenjie Ren
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Haoran Liu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Huimin Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yongfeng Xu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yujuan Han
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Ying Teng
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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11
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Feng JR, Ni HG. A modified method to calculate dual-isotope slopes for the natural attenuation of organic pollutants in the environment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:30399-30408. [PMID: 33963995 DOI: 10.1007/s11356-021-14313-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 05/03/2021] [Indexed: 06/12/2023]
Abstract
Two-dimensional compound-specific isotope analysis has become a powerful tool for distinguishing reaction mechanisms. Lambda (Λ), an essential and important parameter for processing two-dimensional isotope fractionation data, exhibits values specific to a reaction mechanism. In the present article, we modified the existing algorithms for calculation of lambdas based on a review of current methods. Specifically, by regressing [(1000+δE0,2)*(n1*x2)*ΔδEbulk,1] versus [(1000+δE0,1)*(n2*x1)*ΔδEbulk,2] by the York method, a novel method was developed to calculate Λs. The improved method eliminates both the influence of the nonreacting position and the initial isotope signatures. Furthermore, this method retains the advantages of a two-dimensional isotope plot, which eliminates contributions from commitment to catalysis, does not require determination of the fraction of remaining substrate, and can be constructed even from field data. Additionally, the one-sample t test is applied to generate a 95% confidence interval of the dataset of Λris for various reaction mechanisms. The ranges of 5.67-24.8, 8.54-9.80, 0.51-8.35, 25.2-36.8, and 7.09-21.9 are applicable for the oxidation of C-H bonds (ZC=1, ZH=3; ZC and ZH are the number of indistinguishable carbon and hydrogen atoms in intramolecular competition, respectively), oxidation of C-H bonds (ZC=1, ZH=4), aerobic biodegradation of benzene (ZC=6, ZH=6), methanogenic or sulfate-reducing biodegradation of benzene (ZC=6, ZH=6), and nitrate-reducing biodegradation of benzene (ZC=6, ZH=6). The accumulation and correction of these values will make the data measured in the field easier to interpret.
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Affiliation(s)
- Jin-Ru Feng
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, People's Republic of China
| | - Hong-Gang Ni
- School of Urban Planning and Design, Shenzhen Graduate School, Peking University, Shenzhen, 518055, People's Republic of China.
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12
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Wang T, Huang T, Jiang H, Ma R. Electrochemical degradation of atrazine by BDD anode: Evidence from compound-specific stable isotope analysis and DFT simulations. CHEMOSPHERE 2021; 273:129754. [PMID: 33524760 DOI: 10.1016/j.chemosphere.2021.129754] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/16/2021] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
Direct charge transfer (DCT) and •OH attack played important roles in contaminant degradation by BDD electrochemical oxidation. Their separate contributions and potential bond-cleavage processes were required but lacking. Here, we carried out promising compound-specific isotope fractionation analysis (CSIA) to explore 13C and 2H isotope fractionation of atrazine (ATZ), followed by assessing the reaction pathway by BDD anode. The correlation of 2H and 13C fractionation allows to remarkably differentiate DCT process and •OH attack, with Λ values of 18.99 and 53.60, respectively. Radical quenching identified that •OH accounted for 79.0%-88.5% in the whole reaction. While CSIA methods provided biased results, which suggested that ATZ degradation exhibited two stages with •OH contributions of 24.6% and 84.3% respectively, confirming CSIA was more sensitive and provided more possibilities to estimate degradation processes. Combined with Fukui index and intermediate products identification, we deduced that dechlorination-hydroxylation mainly occurred in the first 30 min by DCT reaction. While lateral chain oxidation with C-N broken was the governing route once •OH was largely generated, with the production of DEA (m/z 188), DIA (m/z 174), DEIA (m/z 146) and DEIHA (m/z 128). Our results demonstrated that isotope fractionation can offer "isotopic footprints" for identifying the rate-limiting steps and bond breakage process, and opens new avenues for degradation pathways of contaminants.
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Affiliation(s)
- Ting Wang
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China; State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, Beijing, 100871, China.
| | - Taobo Huang
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China
| | - Huan Jiang
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China
| | - Ruoqi Ma
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China
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Li H, Li X, Jain P, Peng H, Rahimi K, Singh S, Pich A. Dual-Degradable Biohybrid Microgels by Direct Cross-Linking of Chitosan and Dextran Using Azide-Alkyne Cycloaddition. Biomacromolecules 2020; 21:4933-4944. [PMID: 33210916 DOI: 10.1021/acs.biomac.0c01158] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In this work, biocompatible and degradable biohybrid microgels based on chitosan and dextran were synthesized for drug delivery applications. Two kinds of bio-based building blocks, alkyne-modified chitosan and azide-modified dextran, were used to fabricate microgels via single-step cross-linking in water-in-oil emulsions. The cross-linking was initiated in the presence of copper(II) without the use of any extra cross-linkers. A series of pH-responsive and degradable microgels were successfully synthesized by varying the degree of cross-links. The microgels were characterized using 1H NMR and FTIR spectroscopy which proved the successful cross-linking of alkyne-modified chitosan and azide-modified dextran by copper(II)-mediated click reaction. The obtained microgels exhibit polyampholyte character and can carry positive or negative charges in aqueous solutions at different pH values. Biodegradability of microgels was shown at pH 9 or in the presence of Dextranase due to the hydrolysis of carbonate esters in the microgels or 1,6-α-glucosidic linkages in dextran structure, respectively. Furthermore, the microgels could encapsulate vancomycin hydrochloride (VM), an antibiotic, with a high loading of approximately 93.67% via electrostatic interactions. The payload could be released in the presence of Dextranase or under an alkaline environment, making the microgels potential candidates for drug delivery, such as colon-specific drug release.
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Affiliation(s)
- Helin Li
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany.,DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Xin Li
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany.,DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Puja Jain
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Huan Peng
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Khosrow Rahimi
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Smriti Singh
- DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany
| | - Andrij Pich
- Functional and Interactive Polymers, Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany.,DWI-Leibniz-Institute for Interactive Materials e.V., Forckenbeckstraße 50, 52056 Aachen, Germany.,Aachen Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Brightlands Chemelot Campus, Urmonderbaan 22, 6167 RD Geleen, The Netherlands
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Zhang ZM, Yang GP, Zhang HH, Shi XZ, Zou YW, Zhang J. Phthalic acid esters in the sea-surface microlayer, seawater and sediments of the East China Sea: Spatiotemporal variation and ecological risk assessment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 259:113802. [PMID: 31896480 DOI: 10.1016/j.envpol.2019.113802] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 11/12/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
The spatial and temporal distribution, congener profiles and ecological risk of phthalic acid esters (PAEs) were investigated in the seawater and sediment samples from the East China Sea in spring and autumn. The average concentrations of ΣPAEs in water samples were 3.16 ± 2.16 μg L-1 in autumn and 1.63 ± 1.20 μg L-1 in spring. The ΣPAEs in sediment was much higher than that in seawater, with an average value of 7.36 ± 6.70 mg kg-1 (dw). PAEs levels in the sea-surface microlayer (SML) in spring were 3.61 ± 3.36 μg L-1, indicating that the PAEs were noticeably concentrated in the SML, with an average enrichment factor of 2.10. Among the 16 PAE congeners, di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and di(2-ethylhexyl) phthalate (DEHP) were the preponderant PAEs in both sediment and seawater samples. Additionally, PAE concentrations in autumn were higher than those in spring, and this difference resulted mainly from the terrigenous input and marine transportation. The horizontal distributions of PAEs showed an opposite distribution pattern to salinity and temperature, a pattern which might be influenced by the inputs of fresh water. The vertical distributions of ΣPAEs were characterized by high concentrations in the surface waters, with a slight decrease with depth, and then an increase close to the seabed. The results of ecological risk in the water-phase showed that the level of potential risk followed the order of DEHP > DiBP and DnBP > DMP and DEP, which posed a high (DEHP), medium (DiBP and DnBP) and low (DMP and DEP) risk to the sensitive organisms, respectively. For the sediment-phase, DiBP and DnBP represented a high risk to the sensitive organisms, whereas DMP, DEP and DEHP had only a low risk.
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Affiliation(s)
- Ze-Ming Zhang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266100, China; Ningbo University, School of Marine Science, 818 Fenghua Road, Ningbo, 315211, Zhejiang, China
| | - Gui-Peng Yang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266100, China; Institute of Marine Chemistry, Ocean University of China, Qingdao, 266100, China
| | - Hong-Hai Zhang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266100, China; Institute of Marine Chemistry, Ocean University of China, Qingdao, 266100, China
| | - Xi-Zhi Shi
- Ningbo University, School of Marine Science, 818 Fenghua Road, Ningbo, 315211, Zhejiang, China
| | - Ya-Wen Zou
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266100, China
| | - Jing Zhang
- Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Institute for Advanced Ocean Study, Ocean University of China, Qingdao, 266100, China; Institute of Marine Chemistry, Ocean University of China, Qingdao, 266100, China.
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15
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Chen S, Zhang K, Jha RK, Ma L. Impact of atrazine concentration on bioavailability and apparent isotope fractionation in Gram-negative Rhizobium sp. CX-Z. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 257:113614. [PMID: 31761577 DOI: 10.1016/j.envpol.2019.113614] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 11/10/2019] [Accepted: 11/10/2019] [Indexed: 06/10/2023]
Abstract
Compound-specific stable isotope analysis of micropollutants has become an established method for the qualitative and quantitative assessment of biodegradation in the field. However, many of environmental factors may have an influence on the observed isotope fractionation. Herein, we investigate the impact of substrate concentration on the observed enrichment factor derived from Rayleigh plot of batch laboratory experiments conducted to measure the atrazine carbon isotope fractionation of Rhizobium sp. CX-Z subjected to the different initial concentration level of atrazine. The Rayleigh plot (changes in bulk concentration vs. isotopic composition) derived from batch experiments shown divergence from the linear relation towards the end of degradation, confirming bioavailability of atrazine changed along with the decay of substrate concentration, consequently, influenced the isotope fractionation and lowered the observed enrichment factor. When microbial degradation is coupled to a mass transfer step limiting the bioavailability of substrate, the observed enrichment factor displays a dependence on initial atrazine concentration. Observed enrichment factors (ε) (absolute value) derived from the low concentration (i.e. 9.5 μM) are below 3.5‰ to the value of -5.4‰ determined at high bioavailability (membrane-free cells). The observed enrichment factor depended significantly on the atrazine concentration, indicating the concentration level and the bioavailability of a substrate in realistic environments should be considered during the assessment of microbial degradation or in situ bioremediation based on compound-specific stable isotope analysis (CSIA) method.
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Affiliation(s)
- Songsong Chen
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Kai Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China
| | - Rohit Kumar Jha
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China
| | - Limin Ma
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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