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Masbou J, Payraudeau S, Guyot B, Imfeld G. Dimethomorph degradation in vineyards examined by isomeric and isotopic fractionation. CHEMOSPHERE 2023; 313:137341. [PMID: 36423721 DOI: 10.1016/j.chemosphere.2022.137341] [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: 06/29/2022] [Revised: 11/15/2022] [Accepted: 11/19/2022] [Indexed: 06/16/2023]
Abstract
Knowledge of the degradation extent and pathways of fungicides in the environment is scarce. Fungicides may have isomers with distinct fungal-control efficiency, toxicity and fate in the environment, requiring specific approaches to follow up the degradation of individual isomers. Here we examined the degradation of the widely used fungicide dimethomorph (DIM) in a vineyard catchment using ratios of carbon stable isotopes (δ13C) and E/Z isomer fractionation (IF(Z)). In a microcosm laboratory experiment, DIM degradation half-life in soil was 20 ± 3 days, and was associated with significant isomeric (ΔIF(Z) = +30%) and isotopic (Δδ13C up to 7‰) fractionation. This corresponds to an isomer enrichment factor of εIR = -54 ± 6%, suggesting isomer selectivity and similar carbon stable isotopic fractionation values of εDIM-(Z) = -1.6 ± 0.2‰ and εDIM-(E) = -1.5 ± 0.2‰. Isomeric and isotopic fractionation values were used to estimate DIM degradation in topsoil and transport in a vineyard catchment over two wine-growing seasons. DIM concentrations following DIM application were up to 3 μg g-1 in topsoil and 29 μg L-1 in runoff water at the catchment outlet. Accordingly, the IF(Z) and δ13C values of DIM in soil were similar to those observed in DIM commercial formulations. The gradual enrichments in DIM-(Z) and 13C of the residual DIM in soil indicated DIM biodegradation over time. DIM biodegradation estimated based on E/Z isomer and carbon stable isotope ratios in topsoil and runoff water ranged from 0% after DIM application up to 100% at the end of the wine-growing season. DIM biodegradation was overestimated compared to conventional approaches relying on DIM mass balance, field concentrations and half-lives. Altogether, our study highlights the usefulness of combining carbon stable isotopes, E/Z isomers and classical approaches to estimate fungicide degradation at the catchment scale, and uncovers difficulties in using laboratory-derived values in field studies.
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Affiliation(s)
- Jérémy Masbou
- Université de Strasbourg, CNRS, ENGEES, ITES UMR7063, F-67084, Strasbourg, France
| | - Sylvain Payraudeau
- Université de Strasbourg, CNRS, ENGEES, ITES UMR7063, F-67084, Strasbourg, France
| | - Benoit Guyot
- Université de Strasbourg, CNRS, ENGEES, ITES UMR7063, F-67084, Strasbourg, France
| | - Gwenaël Imfeld
- Université de Strasbourg, CNRS, ENGEES, ITES UMR7063, F-67084, Strasbourg, France.
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2
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Blessing M, Baran N. A review on environmental isotope analysis of aquatic micropollutants: Recent advances, pitfalls and perspectives. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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3
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Wu L, Suchana S, Flick R, Kümmel S, Richnow H, Passeport E. Carbon, hydrogen and nitrogen stable isotope fractionation allow characterizing the reaction mechanisms of 1H-benzotriazole aqueous phototransformation. WATER RESEARCH 2021; 203:117519. [PMID: 34391022 DOI: 10.1016/j.watres.2021.117519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/13/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
1H-benzotriazole is part of a larger family of benzotriazoles, which are widely used as lubricants, polymer stabilizers, corrosion inhibitors, and anti-icing fluid components. It is frequently detected in urban runoff, wastewater, and receiving aquatic environments. 1H-benzotriazole is typically resistant to biodegradation and hydrolysis, but can be transformed via direct photolysis and photoinduced mechanisms. In this study, the phototransformation mechanisms of 1H-benzotriazole were characterized using multi-element compound-specific isotope analysis (CSIA). The kinetics, transformation products, and isotope fractionation results altogether revealed that 1H-benzotriazole direct photolysis and indirect photolysis induced by OH radicals involved two alternative pathways. In indirect photolysis, aromatic hydroxylation dominated and was associated with small carbon (εC = -0.65 ± 0.03‰), moderate hydrogen (εH = -21.6‰), and negligible nitrogen isotope enrichment factors and led to hydroxylated forms of benzotriazole. In direct photolysis of 1H-benzotriazole, significant nitrogen (εN = -8.4 ± 0.4 to -4.2 ± 0.3‰) and carbon (εC = -4.3 ± 0.2 to -1.64 ± 0.04‰) isotope enrichment factors indicated an initial N-N bond cleavage followed by nitrogen elimination with a C-N bond cleavage. The results of this study highlight the potential for multi-element CSIA application to track 1H-benzotriazole degradation in aquatic environments.
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Affiliation(s)
- Langping Wu
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George St., Toronto, ON M5S 1A4, Canada
| | - Shamsunnahar Suchana
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George St., Toronto, ON M5S 1A4, Canada
| | - Robert Flick
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5, Canada
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, Leipzig 04318, Germany
| | - Hans Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, Leipzig 04318, Germany
| | - Elodie Passeport
- Department of Civil and Mineral Engineering, University of Toronto, 35 St. George St., Toronto, ON M5S 1A4, Canada; Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5, Canada.
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4
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Exploring the enantiomeric 13C position-specific isotope fractionation: challenges and anisotropic NMR-based analytical strategy. Anal Bioanal Chem 2021; 413:6379-6392. [PMID: 34498104 DOI: 10.1007/s00216-021-03599-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 07/27/2021] [Accepted: 08/03/2021] [Indexed: 10/20/2022]
Abstract
Trying to answer the intriguing and fundamental question related to chiral induction/amplification at the origin of homochirality in Nature: "Is there a relationship between enantiomeric and isotopic fractionation of carbon 13 in chiral molecules?" is a difficult but stimulating challenge. Although isotropic 13C-PSIA NMR is a promising tool for the determination of (13C/12C) ratios capable of providing key 13C isotopic data for understanding the reaction mechanisms of biological processes or artificial transformations, this method does not provide access to any enantiomeric 13C isotopic data unless mirror-image isomers are first physically separated. Interestingly, 13C spectral enantiodiscriminations can be potentially performed in situ in the presence of enantiopure entities as chiral-europium complexes or chiral liquid crystals (CLCs). In this work, we explored for the first time the capabilities of the anisotropic 13C-{1H} NMR using PBLG-based lyotropic CLCs as enantiodiscriminating media in the context of the enantiomeric position-specific 13C isotope fractionation (EPSIF), within the requested precision of the order of the permil. As enantiomeric NMR signals are discriminated on the basis of a difference of 13C residual chemical shift anisotropy (13C-RCSA) prior to being deconvoluted, analysis of enantiomeric mixtures becomes possible. The analytical potential of this approach when using poly-γ-benzyl-L-glutamate (PBLG) is presented, and the preliminary quantitative results on small model chiral molecules obtained at 17.5 T with a cryogenic NMR probe are reported and discussed. A promising analytical approach based on anisotropic irm-13C-NMR spectrometry to potentially reveal the natural 13C/12C isotopic enantiofractionation effects in organic chiral molecules is proposed and discussed.
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Würth A, Menberg K, Martus P, Sültenfuß J, Blum P. Quantifying biodegradation rate constants of o-xylene by combining compound-specific isotope analysis and groundwater dating. JOURNAL OF CONTAMINANT HYDROLOGY 2021; 238:103757. [PMID: 33465657 DOI: 10.1016/j.jconhyd.2020.103757] [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: 06/05/2020] [Revised: 10/26/2020] [Accepted: 12/12/2020] [Indexed: 06/12/2023]
Abstract
The objective of this study is to estimate hydraulic conductivities and biodegradation rate constants in a coal-tar contaminated aquifer by compound-specific isotope analysis (CSIA) and tracer-based (3H-3He) groundwater dating (TGD). In two observation wells downgradient from the contaminant source in situ biodegradation of o-xylene, toluene and naphthalene under sulfate-reducing redox conditions could be demonstrated using CSIA. Median biodegradation rate constants for o-xylene ranging between 0.08 and 0.22 a-1 were estimated. By using tracer-based groundwater dating in these two wells, hydraulic conductivities could be also estimated, which are in a similar range as k-values derived from sieve analysis, a pumping test and a calibrated groundwater flow model. These results clearly demonstrate the applicability of tracer-based groundwater dating for the determination of in situ hydraulic conductivities in aquifers without pumping contaminated groundwater. Finally, a sensitivity analysis is performed using a Monte Carlo simulation. These results indicate high sensitivities of the assumed effective porosity for the estimation of the hydraulic conductivity and the selected isotope enrichment factor for the biodegradation rate constant, respectively. Conversely, the outcome also evidently demonstrates the main limitations of the novel combined isotope approach for a successful implementation of monitored natural attenuation (MNA) at such field sites.
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Affiliation(s)
- Andreas Würth
- Karlsruhe Institute of Technology (KIT), Institute for Applied Geosciences (AGW), Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Kathrin Menberg
- Karlsruhe Institute of Technology (KIT), Institute for Applied Geosciences (AGW), Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Peter Martus
- AECOM Deutschland GmbH, Siemensstraße 10, 63263 Neu-Isenburg, Germany
| | - Jürgen Sültenfuß
- University of Bremen, Institute of Environmental Physics, Otto-Hahn-Allee, 28359 Bremen, Germany
| | - Philipp Blum
- Karlsruhe Institute of Technology (KIT), Institute for Applied Geosciences (AGW), Kaiserstraße 12, 76131 Karlsruhe, Germany.
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Torrentó C, Bakkour R, Glauser G, Melsbach A, Ponsin V, Hofstetter TB, Elsner M, Hunkeler D. Solid-phase extraction method for stable isotope analysis of pesticides from large volume environmental water samples. Analyst 2019; 144:2898-2908. [PMID: 30896686 DOI: 10.1039/c9an00160c] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Compound-specific isotope analysis (CSIA) is a valuable tool for assessing the fate of organic pollutants in the environment. However, the requirement of sufficient analyte mass for precise isotope ratio mass spectrometry combined with prevailing low environmental concentrations currently limits comprehensive applications to many micropollutants. Here, we evaluate the upscaling of solid-phase extraction (SPE) approaches for routine CSIA of herbicides. To cover a wide range of polarity, a SPE method with two sorbents (a hydrophobic hypercrosslinked sorbent and a hydrophilic sorbent) was developed. Extraction conditions, including the nature and volume of the elution solvent, the amount of sorbent and the solution pH, were optimized. Extractions of up to 10 L of agricultural drainage water (corresponding to up to 200 000-fold pre-concentration) were successfully performed for precise and sensitive carbon and nitrogen CSIA of the target herbicides atrazine, acetochlor, metolachlor and chloridazon, and metabolites desethylatrazine, desphenylchloridazon and 2,6-dichlorobenzamide in the sub-μg L-1-range. 13C/12C and 15N/14N ratios were measured by gas chromatography-isotope ratio mass spectrometry (GC/IRMS), except for desphenylchloridazon, for which liquid chromatography (LC/IRMS) and derivatization-GC/IRMS were used, respectively. The method validated in this study is an important step towards analyzing isotope ratios of pesticide mixtures in aquatic systems and holds great potential for multi-element CSIA applications to trace pesticide degradation in complex environments.
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Affiliation(s)
- Clara Torrentó
- Centre for Hydrogeology and Geothermics (CHYN), University of Neuchâtel, 2000 Neuchâtel, Switzerland.
| | - Rani Bakkour
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Gaétan Glauser
- Neuchâtel Platform of Analytical Chemistry (NPAC), University of Neuchâtel, 2000 Neuchâtel, Switzerland
| | - Aileen Melsbach
- Helmholtz Zentrum München, Institute of Groundwater Ecology, 85764 Neuherberg, Germany
| | - Violaine Ponsin
- Centre for Hydrogeology and Geothermics (CHYN), University of Neuchâtel, 2000 Neuchâtel, Switzerland.
| | - Thomas B Hofstetter
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Martin Elsner
- Helmholtz Zentrum München, Institute of Groundwater Ecology, 85764 Neuherberg, Germany and Technical University of Munich, Chair of Analytical Chemistry and Water Chemistry, 81377 Munich, Germany
| | - Daniel Hunkeler
- Centre for Hydrogeology and Geothermics (CHYN), University of Neuchâtel, 2000 Neuchâtel, Switzerland.
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7
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Wu L, Verma D, Bondgaard M, Melvej A, Vogt C, Subudhi S, Richnow HH. Carbon and hydrogen isotope analysis of parathion for characterizing its natural attenuation by hydrolysis at a contaminated site. WATER RESEARCH 2018; 143:146-154. [PMID: 29945030 DOI: 10.1016/j.watres.2018.06.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 06/07/2018] [Accepted: 06/16/2018] [Indexed: 05/22/2023]
Abstract
The applicability of compound-specific isotope analysis (CSIA) for assessing in situ hydrolysis of parathion was investigated in a contaminated aquifer at a former pesticide wastes landfill site. Stable isotope analysis of parathion extracted from groundwater taken from different monitoring wells revealed a maximum enrichment in carbon isotope ratio of +4.9‰ compared to the source of parathion, providing evidence that in situ hydrolysis took place. Calculations based on the Rayleigh-equation approach indicated that the natural attenuation of parathion was up to 8.6% by hydrolysis under neutral and acidic conditions. In degradation experiments with aerobic and anaerobic parathion-degrading microbes, no carbon and hydrogen isotope fractionation of parathion were observed. For the first time, CSIA has been applied for the exclusive assessment of the hydrolysis of phosphorothioate-containing organophosphorus pesticides at a contaminated field site.
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Affiliation(s)
- Langping Wu
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Dipti Verma
- Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, New Delhi 110003, India
| | - Morten Bondgaard
- Department of Environment, Central Denmark Region, Lægårdvej 10, 7500 Holstebro, Denmark
| | - Anja Melvej
- Department of Environment, Central Denmark Region, Lægårdvej 10, 7500 Holstebro, Denmark
| | - Carsten Vogt
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Sanjukta Subudhi
- Environmental and Industrial Biotechnology Division, The Energy and Resources Institute, New Delhi 110003, India
| | - Hans H Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany.
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8
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Masbou J, Meite F, Guyot B, Imfeld G. Enantiomer-specific stable carbon isotope analysis (ESIA) to evaluate degradation of the chiral fungicide Metalaxyl in soils. JOURNAL OF HAZARDOUS MATERIALS 2018; 353:99-107. [PMID: 29649698 DOI: 10.1016/j.jhazmat.2018.03.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 03/23/2018] [Accepted: 03/24/2018] [Indexed: 05/21/2023]
Abstract
Chiral pesticides are often degraded enantioselectively in soils, leading to disparity among enantiomers that may display different toxicity levels. Monitoring pesticide degradation extents and processes remains out of reach in the field using conventional bulk and enantiomer concentration analyses. Enantioselective stable carbon isotope analysis (ESIA) combines compound specific isotope analysis (CSIA) and enantioselective analysis, and bears potential to distinguish enantiomer degradation from non-destructive dissipation. We developed ESIA of the fungicide Metalaxyl, providing the 13C/12C ratios for S-Metalaxyl and R-Metalaxyl separately, and applied it to follow degradation in soil incubation experiments. Significant enantioselective degradation (kS-MTY = 0.007-0.011 day-1 < kR-MTY = 0.03-0.07 day-1) was associated with isotope fractionation (Δδ13CS-MTY ranging from 2 to 6‰). While R-Metalaxyl degradation was rapid (T1/2≈10 days), concomitant enrichment in heavy isotopes of the persistent S-Metalaxyl occurred after 200 days of incubation (εS-Metalaxyl ranging from -1.3 to -2.7‰). In contrast, initial racemic ratios and isotopic compositions were conserved in abiotic experiments, which indicates the predominance of microbial degradation in soils. Degradation products analysis and apparent kinetic isotope effect (AKIE) suggested hydroxylation as a major enantioselective degradation pathway in our soils. Altogether, our study underscores the potential of ESIA to evaluate the degradation extent and mechanisms of chiral micropollutants in soils.
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Affiliation(s)
- Jérémy Masbou
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Fatima Meite
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Benoît Guyot
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Gwenaël Imfeld
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France.
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Marie L, Sylvain P, Benoit G, Maurice M, Gwenaël I. Degradation and Transport of the Chiral Herbicide S-Metolachlor at the Catchment Scale: Combining Observation Scales and Analytical Approaches. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:13231-13240. [PMID: 29056040 DOI: 10.1021/acs.est.7b02297] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Evaluating pesticide degradation and transport in the soil-surface water continuum remains challenging at the catchment scale. Here we investigated the dissipation of the chiral herbicide S-metolachlor (SM) in soil in relation to its transport in runoff. Analyses of SM, transformation products (TPs, i.e., MESA and MOXA), and enantiomers were combined to determine SM degradation at plot and catchment scales. Assisted by modeling, we found that the main dissipation pathways of SM at the plot scale were degradation (71%), volatilization (5%), leaching (8%) and runoff (3%), while 13% of SM persisted in topsoil. This highlights the relevance of degradation processes. TPs could trace the different discharge contributions: MOXA prevailed in runoff water, whereas MESA was associated with slower flowpaths. At the catchment outlet, 11% of SM applied was exported in dissolved or particulate phases or as TPs (in SM mass equivalent). A single event 1 week after application exported 96% of SM, which underlined the potential importance of severe rainfall on seasonal SM export. Enantioselective degradation enriched SM in the R-enantiomer over longer periods and may be associated with slower flowpaths. Altogether, combining observation scales and analytical approaches enabled to quantify SM degradation and to identify how degradation controls SM export at the catchment scale.
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Affiliation(s)
- Lefrancq Marie
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
- LETG-Angers (UMR CNRS 6554), University of Angers , 2 bd Lavoisier, 49045 Angers, France
| | - Payraudeau Sylvain
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
| | - Guyot Benoit
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
| | - Millet Maurice
- Atmospheric Physical Chemistry Department (ICPEES UMR 7515), University of Strasbourg, CNRS , 1 rue Blessig, 67084 Strasbourg cedex, France
| | - Imfeld Gwenaël
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
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Doğan-Subaşı E, Elsner M, Qiu S, Cretnik S, Atashgahi S, Shouakar-Stash O, Boon N, Dejonghe W, Bastiaens L. Contrasting dual (C, Cl) isotope fractionation offers potential to distinguish reductive chloroethene transformation from breakdown by permanganate. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 596-597:169-177. [PMID: 28431360 DOI: 10.1016/j.scitotenv.2017.03.292] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/31/2017] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
cis-1,2-Dichloroethene (cis-DCE) and trichloroethene (TCE) are persistent, toxic and mobile pollutants in groundwater systems. They are both conducive to reductive dehalogenation and to oxidation by permanganate. In this study, the potential of dual element (C, Cl) compound specific isotope analyses (CSIA) for distinguishing between chemical oxidation and anaerobic reductive dechlorination of cis-DCE and TCE was investigated. Well-controlled cis-DCE degradation batch tests gave similar carbon isotope enrichment factors εC (‰), but starkly contrasting dual element isotope slopes Δδ13C/Δδ37Cl for permanganate oxidation (εC=-26‰±6‰, Δδ13C/Δδ37Cl≈-125±47) compared to reductive dechlorination (εC=-18‰±4‰, Δδ13C/Δδ37Cl≈4.5±3.4). The difference can be tracked down to distinctly different chlorine isotope fractionation: an inverse isotope effect during chemical oxidation (εCl=+0.2‰±0.1‰) compared to a large normal isotope effect in reductive dechlorination (εCl=-3.3‰±0.9‰) (p≪0.05). A similar trend was observed for TCE. The dual isotope approach was evaluated in the field before and up to 443days after a pilot scale permanganate injection in the subsurface. Our study indicates, for the first time, the potential of the dual element isotope approach for distinguishing cis-DCE (and TCE) concentration drops caused by dilution, oxidation by permanganate and reductive dechlorination both at laboratory and field scale.
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Affiliation(s)
- Eylem Doğan-Subaşı
- Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium; Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Martin Elsner
- Institute of Groundwater Ecology, Helmholtz Zentrum München-National Research Center for Environmental Health, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Shiran Qiu
- Institute of Groundwater Ecology, Helmholtz Zentrum München-National Research Center for Environmental Health, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Stefan Cretnik
- Institute of Groundwater Ecology, Helmholtz Zentrum München-National Research Center for Environmental Health, Ingolstädter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Siavash Atashgahi
- Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium
| | - Orfan Shouakar-Stash
- Department of Earth Sciences, University of Waterloo, 200 University Avenue W., Waterloo, Ont. N2L 3G1, Canada
| | - Nico Boon
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Winnie Dejonghe
- Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium
| | - Leen Bastiaens
- Flemish Institute for Technological Research (VITO), Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium.
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Niu L, Xu C, Zhu S, Bao H, Xu Y, Li H, Zhang Z, Zhang X, Qiu J, Liu W. Enantiomer signature and carbon isotope evidence for the migration and transformation of DDTs in arable soils across China. Sci Rep 2016; 6:38475. [PMID: 27922096 PMCID: PMC5138824 DOI: 10.1038/srep38475] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 11/09/2016] [Indexed: 11/21/2022] Open
Abstract
Due to the adverse impact of DDTs on ecosystems and humans, a full fate assessment deems a comprehensive study on their occurrence in soils over a large region. Through a sampling campaign across China, we measured the concentrations, enantiomeric fractions (EFs), compound-specific carbon isotope composition of DDT and its metabolites, and the microbial community in related arable soils. The geographically total DDT concentrations are higher in eastern than western China. The EFs and δ13C of o,p’-DDT in soils from western China show smaller deviations from those of racemic/standard compound, indicating the DDT residues there mainly result from atmospheric transport. However, the sources of DDT in eastern China are mainly from historic application of technical DDTs and dicofol. The inverse dependence of o,p’-DDT and p,p’-DDE on temperature evidences the transformation of parent DDT to its metabolites. Initial usage, abiotic parameters and microbial communities are found to be the main factors influencing the migration and transformation of DDT isomers and their metabolites in soils. In addition, a prediction equation of DDT concentrations in soils based on stepwise multiple regression analysis is developed. Results from this study offer insights into the migration and transformation pathways of DDTs in Chinese arable soils, which will allow data-based risk assessment on their use.
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Affiliation(s)
- Lili Niu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Chao Xu
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
| | - Siyu Zhu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Huiming Bao
- Department of Geology &Geophysics, Louisiana State University, Baton Rouge, LA, 70803-4101, USA
| | - Yang Xu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongyi Li
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhijian Zhang
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xichang Zhang
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiguo Qiu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.,College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
| | - Weiping Liu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
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12
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Jin B, Rolle M. Joint interpretation of enantiomer and stable isotope fractionation for chiral pesticides degradation. WATER RESEARCH 2016; 105:178-186. [PMID: 27619494 DOI: 10.1016/j.watres.2016.08.057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 08/22/2016] [Accepted: 08/27/2016] [Indexed: 06/06/2023]
Abstract
Chiral pesticides are important contaminants affecting the health and functioning of aquatic systems. The combination of stable isotope and enantiomer analysis techniques has been recently proposed to better characterize the fate of these contaminants in natural and engineered settings. We introduce a modeling approach with the aim of unifying and integrating the interpretation of isotopic and enantiomeric fractionation. The model is based on the definition of enantiomer-specific isotopologues and jointly predicts the evolution of concentration, enantiomer fractionation, as well as changes in stable isotope ratios of different elements. The method allows evaluating different transformation pathways and was applied to investigate enzymatic degradation of dichlorprop (DCPP), enzymatic degradation of mecoprop methyl ester (MCPPM), and microbial degradation of α-hexachlorocyclohexane (α-HCH) by different bacterial strains and under different redox conditions. The model accurately reproduces the isotopic and enantiomeric data observed in previous experimental studies and precisely captures the dual-dimensional trends characterizing different reaction pathways. Furthermore, the model allows testing possible combinations of enantiomer analysis (EA), compound specific isotope analysis (CSIA), and enantiomer specific isotope analysis (ESIA) to identify and assess isotope and enantiomer selective reaction mechanisms.
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Affiliation(s)
- Biao Jin
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej Building 113, DK-2800 Kgs. Lyngby, Denmark
| | - Massimo Rolle
- Department of Environmental Engineering, Technical University of Denmark, Miljøvej Building 113, DK-2800 Kgs. Lyngby, Denmark.
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13
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Elsner M, Imfeld G. Compound-specific isotope analysis (CSIA) of micropollutants in the environment - current developments and future challenges. Curr Opin Biotechnol 2016; 41:60-72. [PMID: 27340797 DOI: 10.1016/j.copbio.2016.04.014] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/14/2016] [Accepted: 04/12/2016] [Indexed: 10/21/2022]
Abstract
Over the last decade, the occurrence of micropollutants in the environment has become a worldwide issue of increasing concern. Compound-specific stable-isotope analysis (CSIA) of natural isotopic abundance may greatly enhance the evaluation of sources and transformation processes of micropollutants, such as pesticides, personal care products or pharmaceuticals. We summarize recent advances from laboratory studies, review current limitations and analytical challenges associated with low concentrations and high polarity of micropollutants, and delineate the potential of micropolluant CSIA for field applications. We highlight future challenges and prospects regarding source apportionment, identification of biotic and abiotic transformation reactions on a mechanistic level, as well as integrative evaluation of degradation hot spots on the catchment scale. Such advances may feed into a framework for risk assessment of micropollutants that includes CSIA.
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Affiliation(s)
- Martin Elsner
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany.
| | - Gwenaël Imfeld
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), UMR 7517, Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
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14
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Schürner HKV, Maier MP, Eckert D, Brejcha R, Neumann CC, Stumpp C, Cirpka OA, Elsner M. Compound-Specific Stable Isotope Fractionation of Pesticides and Pharmaceuticals in a Mesoscale Aquifer Model. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:5729-39. [PMID: 27100740 DOI: 10.1021/acs.est.5b03828] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Compound-specific isotope analysis (CSIA) receives increasing interest for its ability to detect natural degradation of pesticides and pharmaceuticals. Despite recent laboratory studies, CSIA investigations of such micropollutants in the environment are still rare. To explore the certainty of information obtainable by CSIA in a near-environmental setting, a pulse of the pesticide bentazone, the pesticide metabolite 2,6-dichlorobenzamide (BAM), and the pharmaceuticals diclofenac and ibuprofen was released into a mesoscale aquifer with quasi-two-dimensional flow. Concentration breakthrough curves (BTC) of BAM and ibuprofen demonstrated neither degradation nor sorption. Bentazone was transformed but did not sorb significantly, whereas diclofenac showed both degradation and sorption. Carbon and nitrogen CSIA could be accomplished in similar concentrations as for "traditional" priority pollutants (low μg/L range), however, at the cost of uncertainties (0.4-0.5‰ (carbon), 1‰ (nitrogen)). Nonetheless, invariant carbon and nitrogen isotope values confirmed that BAM was neither degraded nor sorbed, while significant enrichment of (13)C and in particular (15)N corroborated transformation of diclofenac and bentazone. Retardation of diclofenac was reflected in additional (15)N sorption isotope effects, whereas isotope fractionation of transverse dispersion could not be identified. These results provide a benchmark on the performance of CSIA to monitor the reactivity of micropollutants in aquifers and may guide future efforts to accomplish CSIA at even lower concentrations (ng/L range).
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Affiliation(s)
- Heide K V Schürner
- Institute of Groundwater Ecology, Helmholtz Zentrum München , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Michael P Maier
- Institute of Groundwater Ecology, Helmholtz Zentrum München , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Dominik Eckert
- Center for Applied Geosciences, University of Tübingen , Hölderlinstraße 12, 72074 Tübingen, Germany
| | - Ramona Brejcha
- Institute of Groundwater Ecology, Helmholtz Zentrum München , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Claudia-Constanze Neumann
- Institute of Groundwater Ecology, Helmholtz Zentrum München , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Christine Stumpp
- Institute of Groundwater Ecology, Helmholtz Zentrum München , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Olaf A Cirpka
- Center for Applied Geosciences, University of Tübingen , Hölderlinstraße 12, 72074 Tübingen, Germany
| | - Martin Elsner
- Institute of Groundwater Ecology, Helmholtz Zentrum München , Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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15
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Maillard E, Lange J, Schreiber S, Dollinger J, Herbstritt B, Millet M, Imfeld G. Dissipation of hydrological tracers and the herbicide S-metolachlor in batch and continuous-flow wetlands. CHEMOSPHERE 2016; 144:2489-2496. [PMID: 26630289 DOI: 10.1016/j.chemosphere.2015.11.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/04/2015] [Accepted: 11/07/2015] [Indexed: 06/05/2023]
Abstract
Pesticide dissipation in wetland systems with regard to hydrological conditions and operational modes is poorly known. Here, we investigated in artificial wetlands the impact of batch versus continuous-flow modes on the dissipation of the chiral herbicide S-metolachlor (S-MET) and hydrological tracers (bromide, uranine and sulforhodamine B). The wetlands received water contaminated with the commercial formulation Mercantor Gold(®) (960 g L(-1) of S-MET, 87% of the S-enantiomer). The tracer mass budget revealed that plant uptake, sorption, photo- and presumably biodegradation were prominent under batch mode (i.e. characterized by alternating oxic-anoxic conditions), in agreement with large dissipation of S-MET (90%) under batch mode. Degradation was the main dissipation pathway of S-MET in the wetlands. The degradate metolachlor oxanilic acid (MOXA) mainly formed under batch mode, whereas metolachlor ethanesulfonic acid (MESA) prevailed under continuous-flow mode, suggesting distinct degradation pathways in each wetland. R-enantiomer was preferentially degraded under batch mode, which indicated enantioselective biodegradation. The release of MESA and MOXA by the wetlands as well as the potential persistence of S-MET compared to R-MET under both oxic and anoxic conditions may be relevant for groundwater and ecotoxicological risk assessment. This study shows the effect of batch versus continuous modes on pollutant dissipation in wetlands, and that alternate biogeochemical conditions under batch mode enhance S-MET biodegradation.
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Affiliation(s)
- Elodie Maillard
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), UMR 7517, Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Jens Lange
- Chair of Hydrology, University of Freiburg, Fahnenbergplatz, D-79098 Freiburg, Germany
| | - Steffi Schreiber
- Chair of Hydrology, University of Freiburg, Fahnenbergplatz, D-79098 Freiburg, Germany
| | - Jeanne Dollinger
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), UMR 7517, Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Barbara Herbstritt
- Chair of Hydrology, University of Freiburg, Fahnenbergplatz, D-79098 Freiburg, Germany
| | - Maurice Millet
- Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé ICPEES, UMR 7515, Groupe de Physico-Chimie de l'Atmosphère, Université de Strasbourg/CNRS, France
| | - Gwenaël Imfeld
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), UMR 7517, Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France.
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16
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Feld L, Nielsen TK, Hansen LH, Aamand J, Albers CN. Establishment of Bacterial Herbicide Degraders in a Rapid Sand Filter for Bioremediation of Phenoxypropionate-Polluted Groundwater. Appl Environ Microbiol 2016; 82:878-887. [PMID: 26590282 DOI: 10.1128/aem.02600-15.editor] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 11/16/2015] [Indexed: 05/24/2023] Open
Abstract
In this study, we investigated the establishment of natural bacterial degraders in a sand filter treating groundwater contaminated with the phenoxypropionate herbicides (RS)-2-(4-chloro-2-methylphenoxy)propanoic acid (MCPP) and (RS)-2-(2,4-dichlorophenoxy)propanoic acid (DCPP) and the associated impurity/catabolite 4-chlorophenoxypropanoic acid (4-CPP). A pilot facility was set up in a contaminated landfill site. Anaerobic groundwater was pumped up and passed through an aeration basin and subsequently through a rapid sand filter, which is characterized by a short residence time of the water in the filter. For 3 months, the degradation of DCPP, MCPP, and 4-CPP in the sand filter increased to 15 to 30% of the inlet concentration. A significant selection for natural bacterial herbicide degraders also occurred in the sand filter. Using a most-probable-number (MPN) method, we found a steady increase in the number of culturable phenoxypropionate degraders, reaching approximately 5 × 10(5) degraders per g sand by the end of the study. Using a quantitative PCR targeting the two phenoxypropionate degradation genes, rdpA and sdpA, encoding stereospecific dioxygenases, a parallel increase was observed, but with the gene copy numbers being about 2 to 3 log units higher than the MPN. In general, the sdpA gene was more abundant than the rdpA gene, and the establishment of a significant population of bacteria harboring sdpA occurred faster than the establishment of an rdpA gene-carrying population. The identities of the specific herbicide degraders in the sand filter were assessed by Illumina MiSeq sequencing of 16S rRNA genes from sand filter samples and from selected MPN plate wells. We propose a list of potential degrader bacteria involved in herbicide degradation, including representatives belonging to the Comamonadaceae and Sphingomonadales.
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Affiliation(s)
- Louise Feld
- Department of Geochemistry, Geological Survey of Denmark & Greenland, Copenhagen, Denmark
| | | | | | - Jens Aamand
- Department of Geochemistry, Geological Survey of Denmark & Greenland, Copenhagen, Denmark
| | - Christian Nyrop Albers
- Department of Geochemistry, Geological Survey of Denmark & Greenland, Copenhagen, Denmark
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17
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Establishment of Bacterial Herbicide Degraders in a Rapid Sand Filter for Bioremediation of Phenoxypropionate-Polluted Groundwater. Appl Environ Microbiol 2015; 82:878-87. [PMID: 26590282 DOI: 10.1128/aem.02600-15] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 11/16/2015] [Indexed: 02/01/2023] Open
Abstract
In this study, we investigated the establishment of natural bacterial degraders in a sand filter treating groundwater contaminated with the phenoxypropionate herbicides (RS)-2-(4-chloro-2-methylphenoxy)propanoic acid (MCPP) and (RS)-2-(2,4-dichlorophenoxy)propanoic acid (DCPP) and the associated impurity/catabolite 4-chlorophenoxypropanoic acid (4-CPP). A pilot facility was set up in a contaminated landfill site. Anaerobic groundwater was pumped up and passed through an aeration basin and subsequently through a rapid sand filter, which is characterized by a short residence time of the water in the filter. For 3 months, the degradation of DCPP, MCPP, and 4-CPP in the sand filter increased to 15 to 30% of the inlet concentration. A significant selection for natural bacterial herbicide degraders also occurred in the sand filter. Using a most-probable-number (MPN) method, we found a steady increase in the number of culturable phenoxypropionate degraders, reaching approximately 5 × 10(5) degraders per g sand by the end of the study. Using a quantitative PCR targeting the two phenoxypropionate degradation genes, rdpA and sdpA, encoding stereospecific dioxygenases, a parallel increase was observed, but with the gene copy numbers being about 2 to 3 log units higher than the MPN. In general, the sdpA gene was more abundant than the rdpA gene, and the establishment of a significant population of bacteria harboring sdpA occurred faster than the establishment of an rdpA gene-carrying population. The identities of the specific herbicide degraders in the sand filter were assessed by Illumina MiSeq sequencing of 16S rRNA genes from sand filter samples and from selected MPN plate wells. We propose a list of potential degrader bacteria involved in herbicide degradation, including representatives belonging to the Comamonadaceae and Sphingomonadales.
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18
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Xu Z, Shen X, Zhang XC, Liu W, Yang F. Microbial degradation of alpha-cypermethrin in soil by compound-specific stable isotope analysis. JOURNAL OF HAZARDOUS MATERIALS 2015; 295:37-42. [PMID: 25880047 DOI: 10.1016/j.jhazmat.2015.03.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 03/27/2015] [Accepted: 03/28/2015] [Indexed: 06/04/2023]
Abstract
To assess microbial degradation of alpha-cypermethrin in soil, attenuation of alpha-cypermethrin was investigated by compound-specific stable isotope analysis. The variations of the residual concentrations and stable carbon isotope ratios of alpha-cypermethrin were detected in unsterilized and sterilized soils spiked with alpha-cypermethrin. After an 80 days' incubation, the concentrations of alpha-cypermethrin decreased to 0.47 and 3.41 mg/kg in the unsterilized soils spiked with 2 and 10 mg/kg, while those decreased to 1.43 and 6.61 mg/kg in the sterilized soils. Meanwhile, the carbon isotope ratios shifted to -29.14 ± 0.22‰ and -29.86 ± 0.33‰ in the unsterilized soils spiked with 2 and 10 mg/kg, respectively. The results revealed that microbial degradation contributed to the attenuation of alpha-cypermethrin and induced the carbon isotope fractionation. In order to quantitatively assess microbial degradation, a relationship between carbon isotope ratios and residual concentrations of alpha-cypermethrin was established according to Rayleigh equation. An enrichment factor, ϵ = -1.87‰ was obtained, which can be employed to assess microbial degradation of alpha-cypermethrin. The significant carbon isotope fractionation during microbial degradation suggests that CSIA is a proper approach to qualitatively detect and quantitatively assess the biodegradation during attenuation process of alpha-cypermethrin in the field.
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Affiliation(s)
- Zemin Xu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaoli Shen
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Department of Environmental Engineering, Quzhou University, Quzhou 324000, China
| | - Xi-Chang Zhang
- Laboratory for Teaching in Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Weiping Liu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Fangxing Yang
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Department of Effect-Directed Analysis, Helmholtz Center for Environmental Research - UFZ, Leipzig 04318, Germany.
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19
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Elsayed OF, Maillard E, Vuilleumier S, Millet M, Imfeld G. Degradation of chloroacetanilide herbicides and bacterial community composition in lab-scale wetlands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 520:222-231. [PMID: 25817759 DOI: 10.1016/j.scitotenv.2015.03.061] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/17/2015] [Accepted: 03/17/2015] [Indexed: 06/04/2023]
Abstract
Degradation of chloroacetanilide herbicides rac-metolachlor, acetochlor, and alachlor, as well as associated bacterial populations, were evaluated in vertical upflow wetland columns using a combination of hydrochemical and herbicide analyses, and DNA-based approaches. Mass dissipation of chloroacetanilides, continuously supplied at 1.8-1.9 μM for 112 days, mainly occurred in the rhizosphere zone under nitrate and sulphate-reducing conditions, and averaged 61±14%, 52±12% and 29±19% for acetochlor, alachlor and rac-metolachlor, respectively. Metolachlor enantiomer fractions of 0.494±0.009 in the oxic zone and 0.480±0.005 in the rhizosphere zone indicated preferential biodegradation of the S-enantiomer. Chloroacetanilide ethane sulfonic acid and oxanilic acid degradates were detected at low concentrations only (0.5 nM), suggesting extensive degradation and the operation of yet unknown pathways for chloroacetanilide degradation. Hydrochemical parameters and oxygen concentration were major drivers of bacterial composition, whereas exposure to chloroacetanilides had no detectable impact. Taken together, the results underline the importance of anaerobic degradation of chloroacetanilides in wetlands, and highlight the potential of complementary chemical and biological approaches to characterise processes involved in the environmental dissipation of chloroacetanilides.
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Affiliation(s)
- Omniea Fawzy Elsayed
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS), University of Strasbourg/EOST, UMR 7517 CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France; Génétique Moléculaire, Génomique, Microbiologie (GMGM), University of Strasbourg, UMR 7156 CNRS, 28 rue Goethe, 67083 Strasbourg Cedex, France
| | - Elodie Maillard
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS), University of Strasbourg/EOST, UMR 7517 CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Stéphane Vuilleumier
- Génétique Moléculaire, Génomique, Microbiologie (GMGM), University of Strasbourg, UMR 7156 CNRS, 28 rue Goethe, 67083 Strasbourg Cedex, France
| | - Maurice Millet
- Institute of Chemistry for Energy, Environment and Health (ICPEES), University of Strasbourg, UMR 7515 CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Gwenaël Imfeld
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS), University of Strasbourg/EOST, UMR 7517 CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France.
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20
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Badea SL, Danet AF. Enantioselective stable isotope analysis (ESIA) - a new concept to evaluate the environmental fate of chiral organic contaminants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 514:459-466. [PMID: 25687672 DOI: 10.1016/j.scitotenv.2015.01.082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 01/26/2015] [Accepted: 01/26/2015] [Indexed: 06/04/2023]
Abstract
Since 2011, the enantiospecific stable carbon isotope analysis (ESIA) has emerged as an innovative technique to assess the environmental fate of chiral emerging compounds by combining in one experimental technique both compound specific isotope analysis (CSIA) and enantioselective analysis. To date, the ESIA was applied for four classes of compounds: α-hexachlorocyclohexane (α-HCH), polar herbicides (phenoxy acids), synthetic polycyclic musk galaxolide (HHCB), and phenoxyalkanoic methyl herbicides. From an analytical point of view there are factors that are hindering the application of ESIA methods for the field samples: (i.e. amounts of target analyte, matrix effects, GC resolution) and overcoming these factors is challenging. While ESIA was shown as a mature technique for the first three abovementioned class of compounds, no isotope analysis of individual enantiomers could be performed for phenoxyalkanoic methyl herbicides. With respect to field studies, one study showed that ESIA might be a promising tool to distinguish between biotic and abiotic transformation pathways of chiral organic contaminants and even to differentiate between their aerobic and anaerobic biotransformation pathways. The development of ESIA methods for new chiral emerging contaminants in combination with development of multi-element isotope analysis will contribute to a better characterization of transformation pathways of chiral organic contaminants.
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Affiliation(s)
| | - Andrei-Florin Danet
- Department of Analytical Chemistry, University of Bucharest, Faculty of Chemistry, 90-92 Panduri Str., Bucharest 050657, Romania
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21
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Qiu S, Gözdereliler E, Weyrauch P, Lopez ECM, Kohler HPE, Sørensen SR, Meckenstock RU, Elsner M. Small 13C/ 12C Fractionation Contrasts with Large Enantiomer Fractionation in Aerobic Biodegradation of Phenoxy Acids. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:5501-11. [PMID: 24708181 DOI: 10.1021/es405103g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Affiliation(s)
- Shiran Qiu
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstadter Landstr. 1, 85764 Neuherberg, Germany
| | - Erkin Gözdereliler
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstadter Landstr. 1, 85764 Neuherberg, Germany
- Department of Geochemistry, Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, 1350 Copenhagen K, Denmark
| | - Philip Weyrauch
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstadter Landstr. 1, 85764 Neuherberg, Germany
| | - Eva C. Magana Lopez
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstadter Landstr. 1, 85764 Neuherberg, Germany
| | - Hans-Peter E. Kohler
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Überlandstrasse 133, CH-8600 Dübendorf, Switzerland
| | - Sebastian R. Sørensen
- Department of Geochemistry, Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, 1350 Copenhagen K, Denmark
| | - Rainer U. Meckenstock
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstadter Landstr. 1, 85764 Neuherberg, Germany
| | - Martin Elsner
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Ingolstadter Landstr. 1, 85764 Neuherberg, Germany
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22
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Levi S, Hybel AM, Bjerg PL, Albrechtsen HJ. Stimulation of aerobic degradation of bentazone, mecoprop and dichlorprop by oxygen addition to aquifer sediment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 473-474:667-75. [PMID: 24412734 DOI: 10.1016/j.scitotenv.2013.12.061] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/12/2013] [Accepted: 12/12/2013] [Indexed: 05/23/2023]
Abstract
In order to investigate aerobic degradation potential for the herbicides bentazone, mecoprop and dichlorprop, anaerobic groundwater samples from two monitoring and three drinking water wells near a drinking water abstraction field in Nybølle, Denmark, were screened for their degradation potential for the herbicides. In the presence of oxygen (14)C-labelled bentazone and mecoprop were removed significantly from the two monitoring wells' groundwater samples. Oxygen was added to microcosms in order to investigate whether different oxygen concentrations stimulate the biodegradation of the three herbicides in microcosms using groundwater and sandy aquifer materials. To maintain a certain oxygen concentration this level was measured from the outside of the bottles with a fibre oxygen meter using oxygen-sensitive luminescent sensor foil mounted inside the microcosm, to which supplementary oxygen was added. The highest oxygen concentrations (corresponding to 4-11 mg L(-1)) stimulated degradation (a 14-27% increase for mecoprop, 3-9% for dichlorprop and 15-20% for bentazone) over an experimental period of 200 days. Oxygen was required to biodegrade the herbicides, since no degradation was observed under anaerobic conditions. This is the first time bentazone degradation has been observed in aquifer material at low oxygen concentrations (2 mg L(-1)). The sediment had substantial oxygen consumption (0.92-1.45O2 g(-1)dw over 200 days) and oxygen was depleted rapidly in most incubations soon after its addition, which might be due to the oxidation of organic matter and other reduced species such as Fe(2+), S(2-) and Mn in sediment before the biodegradation of herbicides takes place. This study suggests that oxygen enhancement around a drinking water abstraction field could stimulate the bioremediation of diffuse source contamination.
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Affiliation(s)
- S Levi
- Technical University of Denmark, DTU Environment, Department of Environmental Engineering, Miljoevej 113, 2800 Kongens Lyngby, Denmark
| | - A-M Hybel
- Technical University of Denmark, DTU Environment, Department of Environmental Engineering, Miljoevej 113, 2800 Kongens Lyngby, Denmark
| | - P L Bjerg
- Technical University of Denmark, DTU Environment, Department of Environmental Engineering, Miljoevej 113, 2800 Kongens Lyngby, Denmark
| | - H-J Albrechtsen
- Technical University of Denmark, DTU Environment, Department of Environmental Engineering, Miljoevej 113, 2800 Kongens Lyngby, Denmark.
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Prieto A, Rodil R, Quintana JB, Cela R, Möder M, Rodríguez I. Evaluation of polyethersulfone performance for the microextraction of polar chlorinated herbicides from environmental water samples. Talanta 2014; 122:264-71. [PMID: 24720994 DOI: 10.1016/j.talanta.2014.01.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 01/15/2014] [Accepted: 01/20/2014] [Indexed: 10/25/2022]
Abstract
In this work, the suitability of bulk polyethersulfone (PES) for sorptive microextraction of eight polar, chlorinated phenoxy acids and dicamba from environmental water samples is assessed and the analytical features of the optimized method are compared to those reported for other microextraction techniques. Under optimized conditions, extractions were performed with samples (18 mL) adjusted at pH 2 and containing a 30% (w/v) of sodium chloride, using a tubular PES sorbent (1 cm length × 0.7 mm o.d., sorbent volume 8 µL). Equilibrium conditions were achieved after 3h of direct sampling, with absolute extraction efficiencies ranging from 39 to 66%, depending on the compound. Analytes were recovered soaking the polymer with 0.1 mL of ethyl acetate, derivatized and determined by gas chromatography-mass spectrometry (GC-MS). Achieved quantification limits (LOQs) varied between 0.005 and 0.073 ng mL(-1). After normalization with the internal surrogate (IS), the efficiency of the extraction was only moderately affected by the particular characteristics of different water samples (surface and sewage water); thus, pseudo-external calibration, using spiked ultrapure water solutions, can be used as quantification technique. The reduced cost of the PES polymer allowed considering it as a disposable sorbent, avoiding variations in the performance of the extraction due to cross-contamination problems and/or surface modification with usage.
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Affiliation(s)
- Ailette Prieto
- Department of Analytical Chemistry, University of the Basque Country, P.K. 644, 48080 Bilbao, Spain
| | - Rosario Rodil
- Department of Analytical Chemistry, Nutrition and Food Science, IIAA-Institute for Food Analysis and Research, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - José Benito Quintana
- Department of Analytical Chemistry, Nutrition and Food Science, IIAA-Institute for Food Analysis and Research, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Rafael Cela
- Department of Analytical Chemistry, Nutrition and Food Science, IIAA-Institute for Food Analysis and Research, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Monika Möder
- Department of Analytical Chemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, D-04318 Leipzig, Germany
| | - Isaac Rodríguez
- Department of Analytical Chemistry, Nutrition and Food Science, IIAA-Institute for Food Analysis and Research, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
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24
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Bashir S, Fischer A, Nijenhuis I, Richnow HH. Enantioselective carbon stable isotope fractionation of hexachlorocyclohexane during aerobic biodegradation by Sphingobium spp. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:11432-11439. [PMID: 24007541 DOI: 10.1021/es402197s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Carbon isotope fractionation was investigated for the biotransformation of γ- and α- hexachlorocyclohexane (HCH) as well as enantiomers of α-HCH using two aerobic bacterial strains: Sphingobium indicum strain B90A and Sphingobium japonicum strain UT26. Carbon isotope enrichment factors (ε(c)) for γ-HCH (ε(c) = -1.5 ± 0.1 ‰ and -1.7 ± 0.2 ‰) and α-HCH (ε(c) = -1.0 ± 0.2 ‰ and -1.6 ± 0.3 ‰) were similar for both aerobic strains, but lower in comparison with previously reported values for anaerobic γ- and α-HCH degradation. Isotope fractionation of α-HCH enantiomers was higher for (+) α-HCH (ε(c) = -2.4 ± 0.8 ‰ and -3.3 ± 0.8 ‰) in comparison to (-) α-HCH (ε(c) = -0.7 ± 0.2 ‰ and -1.0 ± 0.6 ‰). The microbial fractionation between the α-HCH enantiomers was quantified by the Rayleigh equation and enantiomeric fractionation factors (ε(e)) for S. indicum strain B90A and S. japonicum strain UT26 were -42 ± 16% and -22 ± 6%, respectively. The extent and range of isomer and enantiomeric carbon isotope fractionation of HCHs with Sphingobium spp. suggests that aerobic biodegradation of HCHs can be monitored in situ by compound-specific stable isotope analysis (CSIA) and enantiomer-specific isotope analysis (ESIA). In addition, enantiomeric fractionation has the potential as a complementary approach to CSIA and ESIA for assessing the biodegradation of α-HCH at contaminated field sites.
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Affiliation(s)
- Safdar Bashir
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ , Permoserstraße 15, 04318, Leipzig, Germany
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Fenner K, Canonica S, Wackett LP, Elsner M. Evaluating pesticide degradation in the environment: blind spots and emerging opportunities. Science 2013; 341:752-8. [PMID: 23950532 DOI: 10.1126/science.1236281] [Citation(s) in RCA: 591] [Impact Index Per Article: 53.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The benefits of global pesticide use come at the cost of their widespread occurrence in the environment. An array of abiotic and biotic transformations effectively removes pesticides from the environment, but may give rise to potentially hazardous transformation products. Despite a large body of pesticide degradation data from regulatory testing and decades of pesticide research, it remains difficult to anticipate the extent and pathways of pesticide degradation under specific field conditions. Here, we review the major scientific challenges in doing so and discuss emerging opportunities to identify pesticide degradation processes in the field.
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Affiliation(s)
- Kathrin Fenner
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dubendorf, Switzerland.
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26
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Enantioselective stable isotope analysis (ESIA) of polar herbicides. Anal Bioanal Chem 2013; 405:2825-31. [DOI: 10.1007/s00216-013-6745-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 01/07/2013] [Accepted: 01/13/2013] [Indexed: 10/27/2022]
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