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Zhang X, Zheng Y, Su Z, Wang Z, Zhang J, Jia Z, Kümmel S, Qin C, Liu Y, Wang S, Nijenhuis I, Richnow HH. Anaerobic biotransformation of hexachlorocyclohexane isomers in aqueous condition: Dual CCl isotope fractionation and impact on microbial community compositions. WATER RESEARCH 2024; 254:121389. [PMID: 38492479 DOI: 10.1016/j.watres.2024.121389] [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: 12/19/2023] [Revised: 02/18/2024] [Accepted: 02/26/2024] [Indexed: 03/18/2024]
Abstract
Hexachlorocyclohexane (HCH) isomers are persistent organic pollutants (POPs) with high toxicity, lipid solubility, chemical stability. Despite the current ban on usage of Lindane, residual contamination cannot be ignored, and HCH are frequently detected in groundwater and threaten human health. Cultures capable of degrading α-HCH, β-HCH, γ-HCH, and δ-HCH individually have been enriched in anoxic aqueous conditions. Compound-Specific Isotope Analysis (CSIA) was applied to examine the transformation mechanisms of different HCH isomers by the four enrichment cultures. 16S rRNA sequencing techniques were employed to examine the community composition of the enrichment cultures and detect changes in these communities resulting from adding individual HCH isomers. The results indicated that the ability of the enrichment cultures for dichloroelimination of HCH isomers was inconsistent. During dichloroelimination, different bond cleavage mode of β- and δ-HCH led to distinct isotopic effects. HCH isomers had significant impact on the microbial community, while different microbial communities showed comparable isotopic effects during the transformation of a specific HCH isomer. In addition, bacteria in the phyla Proteobacteria and Firmicutes were proposed as the dominant dechlorinators. This study provides a novel perspective on the mode of bond cleavage during HCH dichloroelimination and the effect of HCH on microbial communities, which could potentially support the evaluation of HCH transformation by CSIA and their effects on the microecosystems of groundwater.
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Affiliation(s)
- Xinyu Zhang
- College of Light Industry and Food Engineering, Guangxi University, Daxue Road 100, Nanning 530004, China
| | - Yan Zheng
- College of Food and Biological Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, China
| | - Ziming Su
- School of Resources, Environment and Materials, Guangxi University, Daxue Road 100, Nanning 530004, China
| | - Zhenyu Wang
- Department of Technical Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany
| | - Jian Zhang
- College of Light Industry and Food Engineering, Guangxi University, Daxue Road 100, Nanning 530004, China
| | - Zhongjun Jia
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Steffen Kümmel
- Department of Technical Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany
| | - Chengrong Qin
- College of Light Industry and Food Engineering, Guangxi University, Daxue Road 100, Nanning 530004, China.
| | - Yaqing Liu
- College of Light Industry and Food Engineering, Guangxi University, Daxue Road 100, Nanning 530004, China.
| | - Shuangfei Wang
- College of Light Industry and Food Engineering, Guangxi University, Daxue Road 100, Nanning 530004, China
| | - Ivonne Nijenhuis
- Department of Technical Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany
| | - Hans H Richnow
- Department of Technical Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany; Isodetect, Deutscher Platz 5b, 04103 Leipzig, Germany
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Xu C, Cai Y, Wang R, Wu J, Yang G, Lv Y, Liu D, Deng Y, Zhu Y, Zhang Q, Wang L, Zhang S. Reduced attention on restricted organochlorine pesticides, whereas still noteworthy of the impact on the deep soil and groundwater: a historical site study in southern China. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:8787-8802. [PMID: 37749354 DOI: 10.1007/s10653-023-01761-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 09/13/2023] [Indexed: 09/27/2023]
Abstract
The use of hexachlorocyclohexanes (HCHs) in pesticides has been prohibited for decades in China. Since then, there have been urbanization and transformation of the functional areas of many sites, which were formerly involved in the HCH industry. However, it is possible that, unless properly managed, these sites may still contain HCH residues in the soil and thus pose a threat to the surrounding environment and the quality of groundwater. This study aimed to characterize soil residues in a typical site that was historically involved in HCH production in southern China, by analyzing the α-HCH, β-HCH, and γ-HCH contents of the soil. The results suggested that HCHs persist in the environment and can have long-term effects. It was found that α-HCH and β-HCH were present in many samples in concentrations that were comparable or higher than those specified by China's Class 1 screening values. The distribution of residues was significantly correlated with the historical HCH production activities in the areas. The characteristic ratios of α-HCH/γ-HCH and β-HCH/(α + γ)-HCH at different soil depths were 1.4-3.7 and 0.21-1.04, respectively, which indicated the presence of significant localized residues of HCHs. The presence of HCHs in the soil suggested a downward migration, with concentrations rapidly decreasing in the upper layer soil (0-5 m), but a gradual increase in the deeper soil (5-14 m). HCHs were detected at depths exceeding 24 m, indicating heavy penetration. The proportions of γ-HCH and β-HCH changed with increasing soil depth, which was related to their relatively volatile and stable molecular structures, respectively. The results strongly suggested that there is widespread contamination of both soil and groundwater by HCHs even after decades. The likelihood of residual HCHs in the soil should therefore be taken into full consideration during urban planning to limit risks to human and environmental health.
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Affiliation(s)
- Changlin Xu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Yue Cai
- State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655, China
| | - Rui Wang
- Department of Municipal and Environmental Engineering, School of Civil Engineering, Beijing Jiaotong University, Beijing, 100044, China
| | - Jing Wu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Guoyi Yang
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Yahui Lv
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Dehong Liu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Yu Deng
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Yaqi Zhu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Qing Zhang
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Ecoenvironmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangzhou, 510650, China
| | - Lijun Wang
- Department of Environmental Science and Engineering, School of Geography and Tourism, Shaanxi Normal University, Xi'an, 710119, China
| | - Shengwei Zhang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China.
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Liu X, Kümmel S, Trapp S, Richnow HH. Uptake and Transformation of Hexachlorocyclohexane Isomers (HCHs) in Tree Growth Rings at a Contaminated Field Site. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37267390 DOI: 10.1021/acs.est.3c01929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The potential transformation of hexachlorocyclohexane isomers (HCHs) within tree trunks could have a significant impact on the use of phytoscreening. However, the transformation mechanisms of HCH in trunks particularly in growth rings are not yet well understood. Therefore, a field study on an HCH-contaminated field site was conducted to investigate the fate of HCH, particularly α-HCH in tree trunks using multielement compound-specific isotope analysis (ME-CSIA) and enantiomer fractionation. The results indicate that α-HCH was transformed, as evidenced by higher δ13C and δ37Cl values detected across different growth ring sections and in the bark compared to those in muck and soil. Remarkably, in the middle growth ring section, δ13C values of HCH were only marginally higher or comparable to those in muck, whereas δ37Cl values were higher than those of the muck, indicating a different transformation mechanism. Moreover, the δ37Cl values of β-HCH also increased in the tree trunks compared to those in soil and muck, implying a transformation of β-HCH. Additionally, dual-element isotope analysis revealed that there are different transformation mechanisms between the middle growth rings and other sections. Our findings suggest that the transformation of HCHs in trunks could bias quantitative phytoscreening approaches; however, ME-CISA offers an option to estimate the degradation extent.
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Affiliation(s)
- Xiao Liu
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Stefan Trapp
- Department of Environmental and Resource Engineering, Technical University of Denmark, Bygningstorvet 115, 2800 Kongens Lyngby, Denmark
| | - Hans Hermann Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
- Isodetect GmbH, Deutscher Platz 5b, 04103 Leipzig, Germany
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Liu X, Yang A, Kümmel S, Richnow HH. Uptake and Metabolization of HCH Isomers in Trees Examined over an Annual Growth Period by Compound-Specific Isotope Analysis and Enantiomer Fractionation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10120-10130. [PMID: 35758406 DOI: 10.1021/acs.est.2c02697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
To understand the role of plants for natural attenuation, a field study was conducted to characterize the fate of HCH in trees over an annual growth period using compound-specific isotope analysis and enantiomer fractionation. Stable and slightly higher δ13C and δ37Cl values of HCH of host soil samples compared to the muck (consisting nearly exclusively of HCH) revealed that masking isotope effects caused by the limited bioavailability may underestimate the real extent of HCH transformation in soil. In contrast, an increase of δ13C and δ37Cl values in trees indicated the transformation of HCH. A large variability of δ13C and δ37Cl values in trees over the growth period was observed, representing different transformation extents among different growth times, which is further supported by the shift of the enantiomer fraction (EF), indicating the preferential transformation of enantiomers also varied over the different growth periods. Based on dual-element isotope analysis, different predominant transformation mechanisms were observed during the growing seasons. Our observation implies that plants are acting as biological pumps driving a cycle of uptake and metabolization of HCH and refeed during littering to soil catalyzing their transformation. The changes of the transformation mechanism in different seasons have implications for phytoscreening and shed new light on phytoremediation of HCH at field sites.
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Affiliation(s)
- Xiao Liu
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, Leipzig 04318, Germany
| | - Ahyung Yang
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, Leipzig 04318, Germany
- The Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, Landau in der Pfalz 76829, Germany
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, Leipzig 04318, Germany
| | - Hans H Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, Leipzig 04318, Germany
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5
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Liu X, Wu L, Kümmel S, Richnow HH. Stable isotope fractionation associated with the synthesis of hexachlorocyclohexane isomers for characterizing sources. CHEMOSPHERE 2022; 296:133938. [PMID: 35149010 DOI: 10.1016/j.chemosphere.2022.133938] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/17/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
The stable isotope fingerprints of hexachlorocyclohexane (HCH) isomers have potential for identifying sources as they are related to the synthesis processes and isotopic compositions of raw materials. However, the isotopic fractionation associated with the synthesis processes has not been investigated. Therefore, photochemical synthesis experiments using benzene and chlorine gas were conducted to characterize the associated isotopic fractionation under different conditions. Different patterns of isotopic fractionation factors (αC, αCl, and αH) were observed in each experiment. The large variability of αH is related to the accumulating secondary hydrogen isotope effects or the rearrangement of C-H bonds at the cyclohexane ring. An increase of δ13C and δ37Cl values of HCH isomers was observed during synthesis, which is related to the C-Cl bond formation in the radical dichlorination forming HCH and the subsequent chlorine substitution forming heptachlorocyclohexanes. The large variability of δ2H values is related to the secondary and primary hydrogen isotope effects. Different δ13C, δ37Cl and δ2H values among HCH isomers were observed, indicating that conformational complexity of HCH caused by arrangement of C-Cl bonds in planar and axial positions also influence the isotope values. The understanding of isotopic fractionation during HCH synthesis can be indicative for source identification in the field.
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Affiliation(s)
- Xiao Liu
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany.
| | - Langping Wu
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany; Department of Civil & Mineral Engineering, University of Toronto, 35 St George St, Toronto, ON M5S 1A4, Canada.
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany.
| | - Hans H Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318, Leipzig, Germany.
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Wang X, Sun J, Liu R, Zheng T, Tang Y. Plant contribution to the remediation of PAH-contaminated soil of Dagang Oilfield by Fire Phoenix. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:43126-43137. [PMID: 35091936 DOI: 10.1007/s11356-021-18230-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
Pot experiments were conducted to evaluate plant contribution during remediation of the polycyclic aromatic hydrocarbons (PAH)-contaminated soil of Dagang Oilfield by Fire Phoenix (a mixture of Festuca L.). The results showed that Fire Phoenix could grow in soil contaminated by high and low concentrations of PAHs. After being planted for 150 days, the total removal rate of six PAHs in the high and low PAH concentrations was 80.36% and 79.79%, significantly higher than the 58.79% and 53.29% of the unplanted control group, respectively. Thus, Fire Phoenix can effectively repair the soil contaminated by different concentrations of PAHs. In high concentrations of PAHs, the results indicated a positive linear relationship between PAH absorption in tissues of Fire Phoenix and the growth time in the early stage. In contrast, the contents of PAHs were just slightly increased in the late period of plant growth. The main factor for the dissipation of PAHs was plant-promoted biodegradation (99.04%-99.93%), suggesting a low contribution of PAH uptake and transformation (0.07%-0.96%). The results revealed that Fire Phoenix did not remove the PAHs in the soil by accumulation but promoted PAH dissipation in the soil by stimulating the microbial metabolism in the rhizosphere.
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Affiliation(s)
- Xiaomei Wang
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang, 110179, China
| | - Jianping Sun
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang, 110179, China
| | - Rui Liu
- Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming, 650500, China.
| | - Tingyu Zheng
- Zhongke Dingshi Environmental Engineering Co., Ltd, Beijing, 100028, China
| | - Yingnan Tang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China
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Zhu M, Tang J, Shi T, Ma X, Wang Y, Wu X, Li H, Hua R. Uptake, translocation and metabolism of imidacloprid loaded within fluorescent mesoporous silica nanoparticles in tomato (Solanum lycopersicum). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 232:113243. [PMID: 35093815 DOI: 10.1016/j.ecoenv.2022.113243] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/17/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
Fluorescence-labeling technology has been widely used for rapid detection of pesticides in agricultural production. However, there are few studies on the use of this technology to investigate pesticide uptake and transport in plants with fluorescent nanoparticle formulations. Here, we investigated uptake, transport, accumulation and metabolism of imidacloprid loaded in fluorescent mesoporous SiO2 nanoparticles (Im@FL-MSNs) in tomato plants, and compared the results with the pesticide application in granular formulation. The results revealed that Im@FL-MSNs applied via root uptake and foliar spray both could effectively transport in tomato plants and carry the imidacloprid to plant tissues. Neither Im@FL-MSNs nor imidacloprid was detected inside of tomato fruits from root uptake or foliar spray applications. Compared with the foliar application of granular formulation, imidacloprid in Im@FL-MSNs demonstrated a higher concentration in leaves (1.14 ± 0.07 mg/kg > 1.08 ± 0.04 mg/kg, 1.13 ± 0.09 mg/kg > 1.11 ± 0.02 mg/kg), longer half-life (0.84 d < 1.31 d, 0.90 d < 1.36 d) and small numbers of metabolites formed. These results suggest that mesoporous silica nanoparticles could serve as an effective and efficient pesticide carrier for achieving the high use efficiency in plant protection. The information is also helpful to guide the pesticide applications and assess the risks associated with environmental quality and dietary consumption of vegetables.
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Affiliation(s)
- Meiqing Zhu
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China; School of Chemical and Environmental Engineering, Anhui Polytechnic University, Wuhu, Anhui 241000, China
| | - Jun Tang
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China
| | - Taozhong Shi
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China
| | - Xin Ma
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China
| | - Yi Wang
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China
| | - Xiangwei Wu
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China
| | - Hui Li
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA.
| | - Rimao Hua
- Key Laboratory of Agri-Food Safety of Anhui Province, School of Resources and Environment, Anhui Agricultural University, No. 130 Changjiang West Road, Hefei 230036, China.
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Liu X, Li W, Kümmel S, Merbach I, Sood U, Gupta V, Lal R, Richnow HH. Soil from a Hexachlorocyclohexane Contaminated Field Site Inoculates Wheat in a Pot Experiment to Facilitate the Microbial Transformation of β-Hexachlorocyclohexane Examined by Compound-Specific Isotope Analysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:13812-13821. [PMID: 34609852 DOI: 10.1021/acs.est.1c03322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
β-Hexachlorocyclohexane (β-HCH) is a remnant from former HCH pesticide production. Its removal from the environment gained attention in the last few years since it is the most stable HCH isomer. However, knowledge about the transformation of β-HCH in soil-plant systems is still limited. Therefore, experiments with a contaminated field soil were conducted to investigate the transformation of β-HCH in soil-plant systems by compound specific isotope analysis (CSIA). The results showed that the δ13C and δ37Cl values of β-HCH in the soil of the planted control remained stable, revealing no transformation due to a low bioavailability. Remarkably, an increase of the δ13C and δ37Cl values in soil and plant tissues of the spiked treatments were observed, indicating the transformation of β-HCH in both the soil and the plant. This was surprising as previously it was shown that wheat is unable to transform β-HCH when growing in hydroponic culture or garden soil. Thus, results of this work indicate for the first time that a microbial community of the soil inoculated the wheat and then facilitated the transformation of β-HCH in the wheat, which may have implications for the development of phytoremediation concepts. A high abundance of HCH degraders belonging to Sphingomonas sp., Mycobacterium sp., and others was detected in the β-HCH-treated bulk and rhizosphere soil, potentially supporting the biotransformation.
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Affiliation(s)
- Xiao Liu
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Wang Li
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
- Institute for Applied Geosciences, Technical University Darmstadt, Schnittspahnstraße 9, 64287 Darmstadt, Germany
| | - Steffen Kümmel
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Ines Merbach
- Department of Community Ecology, Helmholtz Centre for Environmental Research GmbH - UFZ, Theodor-Lieser-Str. 4, 06102 Halle, Germany
| | - Utkarsh Sood
- The Energy and Resources Institute, Lodhi Road, New Delhi 110003, India
| | - Vipin Gupta
- PhiXGen Private Limited, Gurugram, Haryana 122001, India
| | - Rup Lal
- The Energy and Resources Institute, Lodhi Road, 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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