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G H, G S, R S R, R D, R P, R R. Early detection of emerging persistent perfluorinated alkyl substances (PFAS) along the east coast of India. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166155. [PMID: 37562629 DOI: 10.1016/j.scitotenv.2023.166155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 08/04/2023] [Accepted: 08/07/2023] [Indexed: 08/12/2023]
Abstract
Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonate (PFOS) are resistant to breakdown and are now considered global contaminants. However, interest in these recalcitrant compounds among scientists and legislators has grown significantly in recent years. In the present study, we analyzed the level of PFOA and PFOS contamination in surface water from the coastal regions of Tamil Nadu and West Bengal. After solid phase extraction, 49 samples were analyzed by liquid chromatography coupled with mass spectrometry (LOD ≤ 1.5 ng L-1). The PFOA and PFOS present in all samples at the highest concentration were found in the Ennore coastal region (reaching a maximum of 24.8 ng L-1 and 13.9 ng L-1 in CH-6 and CH-14 respectively). Similarly, on the West Bengal coast, concentrations of PFOA ranged from <1.5 to 14.0 ng L-1 and <1.3 to 8.2 ng g-1 in water and sediment respectively. PFOS concentrations in water and sediment ranged from <1.2 to 9.0 ng L-1 and <1.2 to 7.9 ng g-1, respectively. According to the principal component analysis, the majority of the variances (65.04 %) show a positive association, which points to industrial and domestic discharges as significant point sources of these compounds. The results from this study could be used to determine and understand the levels of PFOA and PFOS contamination along the Indian Coast as well as provide baseline information for imminent monitoring investigations. The environmental occurrences of PFOA and PFOS reported in the current study would allow policymakers to take appropriate measures to safeguard coastal ecosystems or reduce the likelihood of contamination, creating a sustainable and healthy environment.
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Affiliation(s)
- Hariharan G
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Anna University Campus, Chennai 600 025, India.
| | - Sunantha G
- School of Biosciences and Technology, Vellore Institute of Technology, Vellore 632 014, India
| | - Robin R S
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Anna University Campus, Chennai 600 025, India
| | - Darwin R
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Anna University Campus, Chennai 600 025, India
| | - Purvaja R
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Anna University Campus, Chennai 600 025, India
| | - Ramesh R
- National Centre for Sustainable Coastal Management, Ministry of Environment, Forest and Climate Change, Anna University Campus, Chennai 600 025, India
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2
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Ma J, Lu Y, Teng Y, Tan C, Ren W, Cao X. Occurrence and health risk assessment of phthalate esters in tobacco and soils in tobacco-producing areas of Guizhou province, southwest China. CHEMOSPHERE 2022; 303:135193. [PMID: 35679984 DOI: 10.1016/j.chemosphere.2022.135193] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Flue-cured tobacco is one of the important sources of national economy in China. However, Phthalic acid esters (PAEs) are ubiquitous contaminants in the cultivation and growth management of flue-cured tobacco, and attracting more and more attention. Here, six priority PAEs were detected in tobacco and soils and their residue characteristics, pollution sources were analyzed, and their exposure risks to the health of farmers were assessed. The concentration of six total PAEs ranged from 0.78 to 4.79 mg/kg in tobacco with the average of 1.75 mg/kg, and 0.84-25.68 mg/kg in soils with the average of 5.40 mg/kg. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) had the highest detection frequency (DF = 100%) both in soil and tobacco samples. DEHP was the most abundant of the total PAEs in soil and tobacco samples, with the mean contribution values of 71.0% and 58.8%, respectively. Principal component analysis (PCA) indicates that the major sources of PAEs in the tobacco-soil system were plastic films, fertilizers and pesticides. Health risk assessment suggests that the non-cancer hazard indexes (NCHI) of dimethyl phthalate (DMP), diethyl phthalate (DEP), DBP and di-n-octyl phthalate (DnOP) in all samples for farmers were at acceptable levels (NCHI < 1), and the average carcinogenic hazard indexes (CHI) of butyl benzyl phthalate (BBP) and DEHP for farmers were 3.79 × 10-13 and 8.54 × 10-11 in soils, respectively, 8.23 × 10-13 and 1.95 × 10-11 in tobacco, respectively, which were considered to be very low level (CHI < 10-6). This study provides data on PAEs in tobacco and soils and their health risks which may provide valuable information to aid the management of tobacco cultivation and risk avoidance.
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Affiliation(s)
- Jun Ma
- School of Geographic Sciences, Hunan Normal University, Changsha, 410081, China; College of Materials and Chemistry, Tongren University, Tongren, 554300, China.
| | - Yingang Lu
- College of Agriculture, Guizhou University, Guiyang, 550025, China
| | - Ying Teng
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Changyin Tan
- School of Geographic Sciences, Hunan Normal University, Changsha, 410081, China.
| | - Wenjie Ren
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Xueying Cao
- Rural Vitalization Research Institute, Changsha University, Changsha, 410022, China
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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 2019; 368:72-80. [PMID: 30665110 DOI: 10.1016/j.jhazmat.2019.01.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 01/05/2019] [Accepted: 01/11/2019] [Indexed: 06/09/2023]
Abstract
There is a lack of understanding about the potential for remobilisation of polycyclic aromatic hydrocarbons (PAHs) residues in soils, specifically after the removal of readily available fractions, and the likelihood to cause harm to human and environmental health. Sequential solvent extractions, using butanol (BuOH), dichloromethane/acetone, and methanolic saponification were used to investigate the time-dependent remobilisation of B[a]P residues in aged soils, after removal of readily available or total-extractable fractions. After 120 d of aging, BuOH-remobilised B[a]P were small or extremely small ranging from 2.3 ± 0.1 mg/kg to 4.5 ± 0.5 mg/kg and from 0.9 ± 0.0 mg/kg to 1.0 ± 0.1 mg/kg, after removal of readily available and total-extractable fractions, respectively. After removal of readily available fractions, the remobilisation rates of B[a]P residues were constant over 5 re-equilibration times, as shown by first-order kinetics. The amounts of B[a]P remobilised significantly (p < 0.05) decreased with aging, particularly in hard organic carbon-rich soils. After 4 years of aging, BuOH- and total-remobilised B[a]P were generally < 5% of the initially spiked 50 mg/kg. Based on the findings of this study, the potential or significant potential for B[a]P NERs in soils to cause significant harm to human and environmental health are minimal.
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Affiliation(s)
- Anthony C Umeh
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Co-operative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Luchun Duan
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Co-operative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Co-operative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Kirk T Semple
- Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom
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Rong X, Zhao G, Fein JB, Yu Q, Huang Q. Role of interfacial reactions in biodegradation: A case study in a montmorillonite, Pseudomonas sp. Z1 and methyl parathion ternary system. JOURNAL OF HAZARDOUS MATERIALS 2019; 365:245-251. [PMID: 30447631 DOI: 10.1016/j.jhazmat.2018.11.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/24/2018] [Accepted: 11/05/2018] [Indexed: 06/09/2023]
Abstract
Organophosphate pesticides are currently the most commonly used pesticides, but the mechanisms of biodegradation of these compounds are often unknown. In this study, we constructed a ternary biodegradation system containing methyl parathion (MP), a bacterial strain of Pseudomonas sp. Z1 with capability of degrading MP and montmorillonite, which is a common clay mineral in soils. The role of interfacial reactions between montmorillonite and the MP degrader on the biodegradation of MP was investigated by batch adsorption as well as through semi-permeable membrane experiments. The contact between degrader and montmorillonite in biodegradation was also dynamically examined using in situ attenuated total reflectance Fourier transform infrared spectroscopy. The metabolic activity of the degrading bacteria was also assessed using an isothermal microcalorimetric technique. The results indicate that sorption of bacterial cells onto montmorillonite enhances the metabolic activity of the bacteria and hence the biodegradation of MP by the bacteria, and that an amide group on a bacterial surface protein is responsible for the bacterial adhesion onto the montmorillonite. This stimulated effect ceased when the bacteria were physically separated from the surface of the clay by a membrane, demonstrating the importance of sorption of both the bacteria and the MP in the biodegradation process.
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Affiliation(s)
- Xingmin Rong
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Gang Zhao
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China; Guangdong Institute of Microbiology, Chinese Academy of Science, Guangzhou 510070, China
| | - Jeremy B Fein
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Qiang Yu
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN, 46556, USA
| | - Qiaoyun Huang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
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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. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 613-614:1140-1153. [PMID: 28954375 DOI: 10.1016/j.scitotenv.2017.09.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 09/02/2017] [Accepted: 09/03/2017] [Indexed: 06/07/2023]
Abstract
The bioavailability and bioaccessibility of polycyclic aromatic hydrocarbons (PAHs) in soil underpin the risk assessment of contaminated land with these contaminants. Despite a significant volume of research conducted in the past few decades, comprehensive understanding of the factors controlling the behaviour of soil PAHs and a set of descriptive soil parameters to explain variations in PAH bioavailability and bioaccessibility are still lacking. This review focuses on the role of source materials on bioavailability and bioaccessibility of soil PAHs, which is often overlooked, along with other abiotic factors including contaminant concentration and mixture, soil composition and properties, as well as environmental factors. It also takes into consideration the implications of different types of risk assessment (ecological and human health) on bioavailability and bioaccessibility of PAHs in soil. We recommend that future research should (1) account for the effects of source materials on bioavailability and bioaccessibility of soil PAHs; (2) adopt non-disruptive methods to analyse soil components controlling PAH sequestration; (3) integrate both natural organic matter (NOM) and xenobiotic organic matter (XOM) while evaluating the influences of soil organic matter (SOM) on the behaviour of PAHs; and (4) consider the dissimilar desorption scenarios in ecological risk assessment and human health risk assessment while assessing PAH bioavailability and bioaccessibility.
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Affiliation(s)
- Linbo Yu
- Global Centre for Environmental Remediation (GCER), ATC Building, University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE Pty Ltd), ATC Building, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Luchun Duan
- Global Centre for Environmental Remediation (GCER), ATC Building, University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE Pty Ltd), ATC Building, University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), ATC Building, University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE Pty Ltd), ATC Building, University of Newcastle, Callaghan, NSW 2308, Australia
| | - Kirk T Semple
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
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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 2017; 98:18-34. [PMID: 27745947 DOI: 10.1016/j.envint.2016.09.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 06/06/2023]
Abstract
Risk-based approaches to managing contaminated land, rather than approaches based on complete contaminant removal, have gained acceptance as they are likely to be more feasible and cost effective. Risk-based approaches aim to minimise risks of exposure of a specified contaminant to humans. However, adopting a risk-based approach over alternative overly-conservative approaches requires that associated uncertainties in decision making are understood and minimised. Irrespective of the nature of contaminants, a critical uncertainty is whether there are potential risks associated with exposure to the residual contaminant fractions in soil to humans and other ecological receptors, and how they should be considered in the risk assessment process. This review focusing on hydrophobic organic contaminants (HOCs), especially polycyclic aromatic hydrocarbons (PAHs), suggests that there is significant uncertainty on the residual fractions of contaminants from risk perspectives. This is because very few studies have focused on understanding the desorption behaviour of HOCs, with few or no studies considering the influence of exposure-specific factors. In particular, it is not clear whether the exposure of soil-associated HOCs to gastrointestinal fluids and enzyme processes release bound residues. Although, in vitro models have been used to predict PAH bioaccessibility, and chemical extractions have been used to determine residual fractions in various soils, there are still doubts about what is actually being measured. Therefore it is not certain which bioaccessibility method currently represents the best choice, or provides the best estimate, of in vivo PAH bioavailability. It is suggested that the fate and behaviour of HOCs in a wide range of soils, and that consider exposure-specific scenarios, be investigated. Exposure-specific scenarios are important for validation purposes, which may be useful for the development of standardised methods and procedures for HOC bioaccessibility determinations. Research is needed to propose the most appropriate testing methods and for assessing potential risks posed by residual fractions of HOCs. Such investigations may be useful for minimising uncertainties associated with a risk-based approach, so that consideration may then be given to its adoption on a global scale. This review critically appraises existing information on the bioavailability of HOC residues in soil to establish whether there may be risks from highly sequestered contaminant residues.
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Affiliation(s)
- Anthony C Umeh
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Co-operative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Luchun Duan
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Co-operative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation (GCER), University of Newcastle, Callaghan, NSW 2308, Australia; Co-operative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Kirk T Semple
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
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Ivshina I, Kostina L, Krivoruchko A, Kuyukina M, Peshkur T, Anderson P, Cunningham C. Removal of polycyclic aromatic hydrocarbons in soil spiked with model mixtures of petroleum hydrocarbons and heterocycles using biosurfactants from Rhodococcus ruber IEGM 231. JOURNAL OF HAZARDOUS MATERIALS 2016; 312:8-17. [PMID: 27015374 DOI: 10.1016/j.jhazmat.2016.03.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 02/12/2016] [Accepted: 03/03/2016] [Indexed: 06/05/2023]
Abstract
Removal of polycyclic aromatic hydrocarbons (PAHs) in soil using biosurfactants (BS) produced by Rhodococcus ruber IEGM 231 was studied in soil columns spiked with model mixtures of major petroleum constituents. A crystalline mixture of single PAHs (0.63g/kg), a crystalline mixture of PAHs (0.63g/kg) and polycyclic aromatic sulfur heterocycles (PASHs), and an artificially synthesized non-aqueous phase liquid (NAPL) containing PAHs (3.00g/kg) dissolved in alkanes C10-C19 were used for spiking. Percentage of PAH removal with BS varied from 16 to 69%. Washing activities of BS were 2.5 times greater than those of synthetic surfactant Tween 60 in NAPL-spiked soil and similar to Tween 60 in crystalline-spiked soil. At the same time, amounts of removed PAHs were equal and consisted of 0.3-0.5g/kg dry soil regardless the chemical pattern of a model mixture of petroleum hydrocarbons and heterocycles used for spiking. UV spectra for soil before and after BS treatment were obtained and their applicability for differentiated analysis of PAH and PASH concentration changes in remediated soil was shown. The ratios A254nm/A288nm revealed that BS increased biotreatability of PAH-contaminated soils.
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Affiliation(s)
- Irina Ivshina
- Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Sciences, 13 Golev Street, 614081 Perm, Russia; Perm State University, 15 Bukirev Street, 614990 Perm, Russia
| | - Ludmila Kostina
- Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Sciences, 13 Golev Street, 614081 Perm, Russia
| | - Anastasiya Krivoruchko
- Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Sciences, 13 Golev Street, 614081 Perm, Russia; Perm State University, 15 Bukirev Street, 614990 Perm, Russia.
| | - Maria Kuyukina
- Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Sciences, 13 Golev Street, 614081 Perm, Russia; Perm State University, 15 Bukirev Street, 614990 Perm, Russia
| | - Tatyana Peshkur
- Strathclyde Eco-Innovation Unit (SEIU), University of Strathclyde, 204 George Street, Glasgow G1 1XQ, United Kingdom
| | - Peter Anderson
- Strathclyde Eco-Innovation Unit (SEIU), University of Strathclyde, 204 George Street, Glasgow G1 1XQ, United Kingdom
| | - Colin Cunningham
- Strathclyde Eco-Innovation Unit (SEIU), University of Strathclyde, 204 George Street, Glasgow G1 1XQ, United Kingdom
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Song M, Jiang L, Zhang D, Luo C, Wang Y, Yu Z, Yin H, Zhang G. Bacteria capable of degrading anthracene, phenanthrene, and fluoranthene as revealed by DNA based stable-isotope probing in a forest soil. JOURNAL OF HAZARDOUS MATERIALS 2016; 308:50-57. [PMID: 26808242 DOI: 10.1016/j.jhazmat.2016.01.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 12/30/2015] [Accepted: 01/06/2016] [Indexed: 06/05/2023]
Abstract
Information on microorganisms possessing the ability to metabolize different polycyclic aromatic hydrocarbons (PAHs) in complex environments helps in understanding PAHs behavior in natural environment and developing bioremediation strategies. In the present study, stable-isotope probing (SIP) was applied to investigate degraders of PAHs in a forest soil with the addition of individually (13)C-labeled phenanthrene, anthracene, and fluoranthene. Three distinct phylotypes were identified as the active phenanthrene-, anthracene- and fluoranthene-degrading bacteria. The putative phenanthrene degraders were classified as belonging to the genus Sphingomona. For anthracene, bacteria of the genus Rhodanobacter were the putative degraders, and in the microcosm amended with fluoranthene, the putative degraders were identified as belonging to the phylum Acidobacteria. Our results from DNA-SIP are the first to directly link Rhodanobacter- and Acidobacteria-related bacteria with anthracene and fluoranthene degradation, respectively. The results also illustrate the specificity and diversity of three- and four-ring PAHs degraders in forest soil, contributes to our understanding on natural PAHs biodegradation processes, and also proves the feasibility and practicality of DNA-based SIP for linking functions with identity especially uncultured microorganisms in complex microbial biota.
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Affiliation(s)
- Mengke Song
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Longfei Jiang
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Dayi Zhang
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Chunling Luo
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Yan Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Zhiqiang Yu
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Hua Yin
- College of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Gan Zhang
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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Xin J, Liu X, Liu W, Zheng X. Effects of biochar-BDE-47 interactions on BDE-47 bioaccessibility and biodegradation by Pseudomonas putida TZ-1. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 106:27-32. [PMID: 24836874 DOI: 10.1016/j.ecoenv.2014.04.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 04/21/2014] [Accepted: 04/22/2014] [Indexed: 06/03/2023]
Abstract
With biochar amendments widely accepted as efficient POPs contamination remediation methods, the post-remediation risk assessment and effectiveness evaluation were urgently needed. So in the study, the effects of biochar -2,2',4,4'-tetrabromodiphenyl ether (BDE-47) interactions on the bioaccessibility and biodegradation of BDE-47 were systematically examined. Biodegradation was monitored over 7 day incubation time with strain Pseudomonas putida TZ-1 and it was revealed that the presence of three model biochars dramatically decreased the biodegradation rate by 87.50-92.19%. The desorption rate gradually decreased to eventually make it a rate-limiting process for BDE-47 biodegradation. To further explore the impact of biochar-BDE-47 sorption on its bioaccessibility, chemical extraction and biosurfactant facilitated desorption experiments were conducted. Both results suggested that almost all the molecules sorbed onto non-porous biochars could be completely desorbed, whereas BDE-47 molecules sequestered within deep micropores were more persistent on the solid phase, and resulted in lower bioaccessibility.
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Affiliation(s)
- Jia Xin
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China.
| | - Xiang Liu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Wei Liu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Xilai Zheng
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
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10
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Crampon M, Bureau F, Akpa-Vinceslas M, Bodilis J, Machour N, Le Derf F, Portet-Koltalo F. Correlations between PAH bioavailability, degrading bacteria, and soil characteristics during PAH biodegradation in five diffusely contaminated dissimilar soils. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:8133-8145. [PMID: 24671402 DOI: 10.1007/s11356-014-2799-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 03/11/2014] [Indexed: 06/03/2023]
Abstract
The natural biodegradation of seven polycyclic aromatic hydrocarbons (PAHs) by native microorganisms was studied in five soils from Normandy (France) from diffusely polluted areas, which can also pose a problem in terms of surfaces and amounts of contaminated soils. Bioavailability tests using cyclodextrin-based extractions were performed. The natural degradation of low molecular weight (LMW) PAHs was not strongly correlated to their bioavailability due to their sorption to geosorbents. Conversely, the very low degradation of high molecular weight (HMW) PAHs was partly correlated to their poor availability, due to their sorption on complexes of organic matter and kaolinites or smectites. A principal component analysis allowed us to distinguish between the respective degradation behaviors of LMW and HMW PAHs. LMW PAHs were degraded in less than 2-3 months and were strongly influenced by the relative percentage of phenanthrene-degrading bacteria over total bacteria in soils. HMW PAHs were not significantly degraded, not only because they were less bioavailable but also because of a lack of degrading microorganisms. Benzo[a]pyrene stood apart since it was partly degraded in acidic soils, probably because of a catabolic cooperation between bacteria and fungi.
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Affiliation(s)
- M Crampon
- COBRA UMR CNRS 6014, Université de Rouen, 55 rue saint Germain, 27000, Evreux, France,
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Chen G, Cheng L, Ding A, Jiang L. Effects of Metallic Cations on Desorption of Phenanthrene and Fluoranthene from Long-Term Contaminated Soil Particles. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.proeng.2011.11.066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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12
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Yap CL, Gan S, Ng HK. Application of vegetable oils in the treatment of polycyclic aromatic hydrocarbons-contaminated soils. JOURNAL OF HAZARDOUS MATERIALS 2010; 177:28-41. [PMID: 20006435 DOI: 10.1016/j.jhazmat.2009.11.078] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 10/21/2009] [Accepted: 11/12/2009] [Indexed: 05/21/2023]
Abstract
A brief review is conducted on the application of vegetable oils in the treatment of PAH-contaminated soils. Three main scopes of treatment strategies are discussed in this work including soil washing by oil, integrated oil-biological treatment and integrated oil-non-biological treatment. For each of these, the arguments supporting vegetable oil application, the applied treatment techniques and their efficiencies, associated factors, as well as the feasibility of the techniques are detailed. Additionally, oil regeneration, the environmental impacts of oil residues in soil and comparison with other commonly employed techniques are also discussed.
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Affiliation(s)
- C L Yap
- Department of Chemical and Environmental Engineering, The University of Nottingham Malaysia Campus, Jalan Broga, 43500 Semenyih, Selangor Darul Ehsan, Malaysia
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Rhodes AH, McAllister LE, Semple KT. Linking desorption kinetics to phenanthrene biodegradation in soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2010; 158:1348-1353. [PMID: 20172637 DOI: 10.1016/j.envpol.2010.01.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 01/03/2010] [Accepted: 01/11/2010] [Indexed: 05/28/2023]
Abstract
The desorption of polycyclic aromatic hydrocarbons (PAHs) often exhibits a biphasic profile similar to that observed for biodegradation whereby an initial rapid phase of degradation or desorption is followed by a phase of much slower transformation or release. Most investigations to-date have utilised a polymeric sorbent, such as Tenax, to characterise desorption, which is methodologically unsuitable for the analysis of soil. In this study, desorption kinetics of (14)C-phenanthrene were measured by consecutive extraction using aqueous solutions of hydroxypropyl-beta-cyclodextrin (HPCD). The data indicate that the fraction extracted after 24 h generally approximated the linearly sorbed, rapidly desorbing fraction (F(rap)), calculated using a three-compartment model. A good linear correlation between phenanthrene mineralised and F(rap) was observed (r(2) = 0.89; gradient = 0.85; intercept = 8.20). Hence HPCD extraction (24 h) and first-order three-compartment modelling appear to provide an operationally straightforward tool for estimating mass-transfer limited biodegradation in soil.
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Affiliation(s)
- Angela H Rhodes
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
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Rhodes AH, McAllister LE, Chen R, Semple KT. Impact of activated charcoal on the mineralisation of 14C-phenanthrene in soils. CHEMOSPHERE 2010; 79:463-469. [PMID: 20171713 DOI: 10.1016/j.chemosphere.2010.01.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 01/14/2010] [Accepted: 01/15/2010] [Indexed: 05/28/2023]
Abstract
The development of phenanthrene catabolism in four soils amended with varying concentrations of activated charcoal (AC) (0%, 0.1%, 1% and 5%), a type of black carbon, was investigated. Mineralisation of (14)C-phenanthrene was monitored after 1, 25, 50 and 100 d soil-PAH contact time; lag phases, rates and extents of mineralisation of the (14)C-phenanthrene to (14)CO(2) were determined. At concentrations >0.1% AC rates and extents of mineralisation were reduced by more than 99%. This revealed that the presence of >0.1% AC in soils may substantially diminish the rate at which the catabolic activity of indigenous soil microflora develops in contaminated soil. Soil C, which had the highest organic carbon (OC) content, consistently exhibited the highest extents of degradation. It is suggested that, in accordance with other researchers, OC may have blocked available phenanthrene sorption sites. This enhanced phenanthrene availability ultimately facilitated a greater level of catabolic activity within this soil. Such results reflect the complex nature of interactions between soil, biota and contaminants and their influence on the degradation of contaminants in the environment.
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Affiliation(s)
- Angela H Rhodes
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom
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15
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Ke L, Bao W, Chen L, Wong YS, Tam NFY. Effects of humic acid on solubility and biodegradation of polycyclic aromatic hydrocarbons in liquid media and mangrove sediment slurries. CHEMOSPHERE 2009; 76:1102-1108. [PMID: 19433332 DOI: 10.1016/j.chemosphere.2009.04.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Revised: 04/03/2009] [Accepted: 04/08/2009] [Indexed: 05/27/2023]
Abstract
The effects of humic acid (HA) on the solubility and biodegradability of mixed polycyclic aromatic hydrocarbons (PAHs) (phenanthrene (PHE), pyrene (PYR), and benzo[a]pyrene (BAP)) in liquid media and mangrove sediment slurries were investigated. The addition of HA to the liquid media (0-1.6%, w/v) significantly enhanced the solubility of all mixed three PAHs and the biodegradation of PHE and PYR (but not BAP) by MP-PYR1, a PYR-degrading bacterium isolated from mangrove sediment. Amendment with 0.2% HA to the sediment slurries exhibited little enhancement in either PAH solubility or degradation. Although amendment with 1.6% HA increased the aqueous phase PAHs in the sediment slurries, it did not have any significant enhancement effect on biodegradation. Natural attenuation of PHE in sediment was evident, with 91% degraded after 7 d. The highest biodegradation of PHE and PYR was found in the sediment slurries inoculated with MP-PYR1, and the degradation efficiency was even higher than that in the liquid media (99% vs. 85% for PHE and 97% vs. 63% for PYR). The degradation capacity of MP-PYR1 for both PHE and PYR was comparable when it was inoculated to the sterile and non-sterile sediment slurries, implying that the inoculum was able to compete with the indigenous microorganisms. The reason why BAP was not degraded in either liquid media or mangrove sediment slurries was more likely due to the lack of degraders than its low solubility. These results suggested that the success of PAH degradation did not rely solely on the amounts of soluble PAHs which could be enhanced by the HA amendment; the presence of a suitable degrader was also important.
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Affiliation(s)
- Lin Ke
- South China University of Technology, Guangzhou, Guangdong, PR China
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16
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Jones MD, Singleton DR, Carstensen DP, Powell SN, Swanson JS, Pfaender FK, Aitken MD. Effect of incubation conditions on the enrichment of pyrene-degrading bacteria identified by stable-isotope probing in an aged, PAH-contaminated soil. MICROBIAL ECOLOGY 2008; 56:341-349. [PMID: 18165874 DOI: 10.1007/s00248-007-9352-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2006] [Revised: 11/20/2007] [Accepted: 11/30/2007] [Indexed: 05/25/2023]
Abstract
To determine whether the diversity of pyrene-degrading bacteria in an aged polycyclic aromatic hydrocarbon-contaminated soil is affected by the addition of inorganic nutrients or by slurrying the soil, various incubation conditions (all including phosphate buffer) were examined by mineralization studies and stable-isotope probing (SIP). The addition of nitrogen to either continuously mixed slurry or static field-wet soil incubations increased the rate and extent of mineralization of [(14)C]pyrene, with the most rapid mineralization observed in slurried, nitrogen-amended soil. Microcosms of slurry and static field-wet soil amended with nitrogen were also examined by SIP with [U-(13)C]pyrene. Recovered (13)C-enriched deoxyribonucleic acid (DNA) was analyzed by denaturing-gradient gel electrophoresis (DGGE) and 16S ribosomal ribonucleic acid (rRNA) gene clone libraries. DGGE profiles of (13)C-enriched DNA fractions from both incubation conditions were similar, suggesting that pyrene-degrading bacterial community diversity may be independent of treatment method. The vast majority (67 of 71) of the partial sequences recovered from clone libraries were greater than or equal to 97% similar to one another, 98% similar to sequences of pyrene-degrading bacteria previously detected by SIP with pyrene in different soil, and only 89% similar to the closest cultivated genus. All of the sequences recovered from the field-wet incubation and most of the sequences recovered from the slurry incubation were in this clade. Of the four sequences from slurry incubations not within this clade, three possessed greater than 99% similarity to the 16S rRNA gene sequences of phylogenetically dissimilar Caulobacter spp.
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Affiliation(s)
- Maiysha D Jones
- Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431, USA
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17
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Jurjanz S, Rychen G. In vitro bioaccessibility of soil-bound polycyclic aromatic hydrocarbons in successive digestive compartments in cows. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:8800-5. [PMID: 17880154 DOI: 10.1021/jf0708950] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Ruminants, which have a central place in the food chain, ingest soil that may contain pollutants. The bioaccessibility of three different polycyclic aromatic hydrocarbon compounds from soil was studied using an in vitro model based on the digestive tract of cows. For this purpose, pasture soil was spiked with (14)C radio-labeled compounds, aged, and then exposed to conditions which simulated the digestive compartments of the rumen, abomasum, and intestines. Our results show that aging generally reduced the bioaccessibility of all the compounds tested. Total bioaccessibilty in the first digestive compartment, i.e., the rumen, depended on the considered compound: elevated for phenanthrene (17-24%), moderate for pyrene (6.6-8.1%), and low for benzo[ a]pyrene (2.3-3.6%). Bioaccessibility was very low in abomasal acidity (generally <2%) and intestinal colloids (<8%). The liquid phases of intestinal medium successfully extracted compounds from freshly contaminated soil (25-28%), but the bioaccessibilty dropped markedly after aging (17% for phenanthrene and <9% for the more lipophylic compounds). Total bioaccessibilty in this in vitro model ranged from 11% for benzo[ a]pyrene in aged soil to 58% for phenanthrene in freshly contaminated soil, and the bioaccessibility of this latter compound was always higher compared to pyrene or benzo[ a]pyrene. Residual soil contained around half of the initial load, the highest residual levels being of benzo[ a]pyrene, which confirms the observed bioaccessibility.
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Affiliation(s)
- Stefan Jurjanz
- INPL-INRA, UR Animal et Fonctionnalités des Produits Animaux, ENSAIA de Nancy, BP 172, 2 avenue de la Forêt de Haye, 54505 Vandoeuvre cedex, France.
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18
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Chevron Cottin N, Merlin G. Study of pyrene biodegradation capacity in two types of solid media. THE SCIENCE OF THE TOTAL ENVIRONMENT 2007; 380:116-23. [PMID: 17462711 DOI: 10.1016/j.scitotenv.2007.03.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2005] [Revised: 01/11/2007] [Accepted: 03/14/2007] [Indexed: 05/15/2023]
Abstract
Removal of pyrene, a representative PAH, was studied using laboratory tests in two different types of solid media: an organic matter collected on the surface of a vertical flow constructed wetland (VFCW) and a formulated clay silicate sand (inorganic matter). The aim of this study was to evaluate the capacity of pyrene biodegradation in these media in order to use them for treating run-off water. The sorption process, the kinetics of pyrene biodegradation and the influence of selected bacteria were also investigated. The sorption process was evaluated by adsorption isotherms and desorption kinetics using a batch equilibration method. The adsorption coefficient values of 28.8 and 2.1 for the organic and the inorganic matter respectively, confirmed the relationship of adsorption with organic carbon content. A small proportion of the sorbed pyrene was available for desorption (8% and 15% for the organic and the inorganic matter, respectively), indicating that sorption was partially irreversible, with the presence of hysteresis. For the formulated clay silicate sand inoculated with a specific bacteria (Mycobacterium sp.6PY1), selected for its ability to degrade PAHs, pyrene removal was complete in 32 days. With the organic matter, these values ranged from 40% to 95% for the different experiments, following a lag time of 3 weeks before observation of a significant degradation. Indigenous bacterial species in the organic medium had the metabolic capacity to degrade pyrene, and microbial populations pre-exposed to the PAH degraded pyrene faster than similar unexposed populations. Three metabolites of pyrene degradation by Mycobacterium were found. They accumulated in both organic and inorganic matter, indicating that the enzymes catalyzing them have slow kinetics.
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Affiliation(s)
- N Chevron Cottin
- Laboratoire d'Optimisation et Conception en Ingénierie de l'Environnement (LOCIE), ESIGEC-Université de Savoie, 73376 Le Bourget du Lac, France.
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Xia XH, Yu H, Yang ZF, Huang GH. Biodegradation of polycyclic aromatic hydrocarbons in the natural waters of the Yellow River: effects of high sediment content on biodegradation. CHEMOSPHERE 2006; 65:457-66. [PMID: 16540147 DOI: 10.1016/j.chemosphere.2006.01.075] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Revised: 11/13/2005] [Accepted: 01/25/2006] [Indexed: 05/07/2023]
Abstract
The contamination of polycyclic aromatic hydrocarbons (PAHs) has become one of the major problems in the Yellow River of China. As the Yellow River is the most turbid large river in the world, it remains unknown to which extent the high suspended sediment content in the river may affect the fate and effect of PAHs. Here we report the effect of sediment on biodegradation of chrysene, benzo(a)pyrene and benzo(g,h,i)perylene with phenanthrene as a co-metabolism substrate in natural waters from the Yellow River. Biodegradation kinetics of the PAHs in the river water with various levels of sediment contents were studied in the laboratory by fitting with a biodegradation kinetics model for organic compounds not supporting growth. The results indicated that the biodegradation rates of PAHs increased with the sediment content in the water. When the sediment contents were 0, 4 and 10 g/l, the biodegradation rate constants of chrysene with the initial concentration of 3.80 microg/l were 0.053, 0.084 and 0.111 d(-1), respectively. Further studies suggested the enhanced biodegradation rate in the presence of sediment was caused by the following mechanisms: (1) the population of PAH-degrading bacteria in the water system was found to increase with the sediment content; the bacteria population on sediment phase was far greater than that on water phase during the cultivation process; (2) the sorption of PAHs on the sediment phase was well described by the dual adsorption-partition model. Although the sorption capacity of PAH per unit weight of sediment decreased with the increase of the sediment content, the amount of sorbed PAH increased with the sediment content; and, (3) the desorption of PAHs from the solid phase led to a higher concentration near the water-sediment interface. Since the bacteria were also attached to the interface, this resulted in an increased contact chance between the bacteria and PAHs.
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Affiliation(s)
- X H Xia
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
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20
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Leglize P, Saada A, Berthelin J, Leyval C. Evaluation of matrices for the sorption and biodegradation of phenanthrene. WATER RESEARCH 2006; 40:2397-404. [PMID: 16735045 DOI: 10.1016/j.watres.2006.03.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2005] [Revised: 03/27/2006] [Accepted: 03/29/2006] [Indexed: 05/09/2023]
Abstract
Permeable reactive barriers (PRBs), a new cost effective technology for the remediation of contaminated groundwater, have rarely been considered for PAH contamination. We evaluated three candidate matrices (activated carbon (AC), pouzzolana coated (PzF) or not (Pz) with heavy fuel oil) for phenanthrene (PHE) sorption capacity and the biodegradation of adsorbed PHE. Adsorption-desorption batch experiments showed higher sorption capacity of AC than PzF (60 fold) and Pz (1,500 fold). Sorption isotherms were not linear for all matrices as described by a Freundlich model. Phenanthrene desorption from AC and PzF within 48 h was limited (1-3%). Mineralization of (14)C-PHE by a PAH-degrading bacterial strain increased in the presence of AC and Pz (+16 and +12%). Among the three matrices, AC may be a good candidate for PRBs due to high adsorption, low desorption and increased PHE degradation.
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Affiliation(s)
- Pierre Leglize
- Laboratoire des Interactions Microorganismes, Minéraux, Matière Organique dans les Sols, LIMOS, UMR 7137 CNRS-UHP Nancy I, Faculté des Sciences, BP 239, F54506 Vandoeuvre-lès-Nancy Cedex, France
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21
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Antízar-Ladislao B, Lopez-Real J, Beck AJ. Investigation of organic matter dynamics during in-vessel composting of an aged coal-tar contaminated soil using fluorescence excitation-emission spectroscopy. CHEMOSPHERE 2006; 64:839-47. [PMID: 16330081 DOI: 10.1016/j.chemosphere.2005.10.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Revised: 10/19/2005] [Accepted: 10/25/2005] [Indexed: 05/05/2023]
Abstract
In-vessel composting of an aged coal-tar contaminated soil from a manufactured gas plant site was investigated over 98days using laboratory-scale in-vessel composting reactors. The composting reactors were operated at 18 different operational conditions using a logistic three-factor factorial design with three temperatures (T=38, 55 and 70 degrees C), four soil to green waste ratios (S:GW; 0.6:1, 0.7:1, 0.8:1 and 0.9:1 on a dry weight basis) and three moisture contents (MC; 40%, 60% and 80%). Excitation-emission matrix (EEM) fluorescence spectroscopy was used to investigate organic matter dynamics in the composting mixture. The results of this investigation indicated that formation of humic substances can be monitored by fluorescence excitation-emission matrix, and provided evidence of progressive mineralization or humification of the composting mixture. Peak excitation wavelength shifts and peak fluorescence intensity can both be used as indicators to monitor the humification or maturation of compost. Finally, the fluorescence index can be applied to investigate the origin of humic substances and fulvic acids, and the humification or maturation of compost.
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Affiliation(s)
- Blanca Antízar-Ladislao
- Imperial College London, Wye campus, Agriculture Science, High Street, Wye, Ashford, Kent TN25 5AH, United Kingdom.
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