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Liu Y, Hou X, Li X, Liu J, Jiang G. Simultaneous determination of 19 bromophenols by gas chromatography-mass spectrometry (GC-MS) after derivatization. Talanta 2024; 274:126015. [PMID: 38581850 DOI: 10.1016/j.talanta.2024.126015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/26/2024] [Accepted: 03/29/2024] [Indexed: 04/08/2024]
Abstract
Bromophenols (BPs) are a class of ubiquitous emerging halogenated pollutants. Their 19 congeners are problematically separated and detected. This work described the separation and detection of 19 BP congeners by gas chromatography-mass spectrometry (GC-MS). Investigations into the derivatization of bromophenols were carried out using two silylation reagents (N,O-bis(trimethylsilyl)trifluoroacetamide and N-methyl-N-(trimethylsily)trifluoroacetamide), two alkylation reagents (methyl iodide and trimethylsilyldiazomethane) and acetic anhydride prior to GC-MS analysis. Optimal chromatographic separation, sensitivity, and linearity were achieved after BP derivatization using acetic anhydride, featuring the equipment detection limits of 0.39-1.26 pg and correlation coefficients of 0.9948-0.9999 (linear range: 0.5-250 ng mL-1) for all 19 BP congeners. Furthermore, the simultaneous determination of 19 bromophenols and 19 bromoanisoles, common environmental transformation products of BPs, is also demonstrated. The improved analytical performance on GC-MS after derivatization would benefit investigations on the environmental origins, behaviors and fates of BPs and their environmental metabolites.
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Affiliation(s)
- Yanwei Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Laboratory of Environmental Nanotechnology and Health Effect, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Xingwang Hou
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Xiaoying Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Environmental Science and Engineering, Dalian Maritime University, Dalian, 116026, China
| | - Jiyan Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China.
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China; School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, China
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2
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Kim DH, Choi S, Park J, Kim K, Oh JE. Phenolic compounds in the freshwater environment in South Korea: Occurrence and tissue-specific distribution. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:166914. [PMID: 37689198 DOI: 10.1016/j.scitotenv.2023.166914] [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: 08/01/2023] [Revised: 09/06/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023]
Abstract
In this study, we investigated the occurrence and distribution of phenolic compounds, including phenol, cresols, chlorophenols, nitrophenol, and bromophenols, in freshwater environments. We also focused on phenolic compounds in crucian carp (Carassius auratus) tissues, specifically the muscle, gills, brain, blood, liver, and gonads, to assess their potential bioaccumulation in fish and human health risks. Phenolic compounds were found to be widespread in various freshwater environments throughout South Korea. Phenol was predominant in all matrices, with median concentrations of 57.0 ng/L in freshwater, 54.3 ng/g dry weight (dw) in sediment, and ranging from 71 ng/g wet weight (ww) to 621 ng/g ww in crucian carp tissues. Cresols were the second most dominant compound, with m-cresol exhibiting the highest prevalence. Most of the compounds detected in crucian carp samples were also detected in freshwater and sediment, whereas pentachlorophenol and 2,4,6-tribromophenol were exclusively detected in crucian carp tissues. A high bioaccumulation potential in the liver was observed for most phenolic compounds [median log bioconcentration factor (BCF): 3.2-3.7]. Interestingly, only m-cresol showed high bioaccumulation potential in the gills (median log BCF: 3.1). The estimated daily intake of phenolic compounds suggested that it does not pose an immediate concern for human exposure owing to crucian carp consumption. These findings enhance our understanding of the exposure status, distribution, and bioaccumulation potency of phenolic compounds in aquatic ecosystems and emphasize the importance of ongoing monitoring and risk assessment efforts.
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Affiliation(s)
- Da-Hye Kim
- Institute for Environment and Energy, Pusan National University, Busan 46241, Republic of Korea
| | - Sol Choi
- Institute for Environment and Energy, Pusan National University, Busan 46241, Republic of Korea
| | - Jaeyeon Park
- Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea
| | - Kyungtae Kim
- Risk Assessment Division, National Institute of Environmental Research (NIER), Incheon 22689, Republic of Korea
| | - Jeong-Eun Oh
- Institute for Environment and Energy, Pusan National University, Busan 46241, Republic of Korea; Department of Civil and Environmental Engineering, Pusan National University, Busan 46241, Republic of Korea.
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3
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Klimm A, Vetter W. Hydroxylated transformation products obtained after UV irradiation of the current-use brominated flame retardants hexabromobenzene, pentabromotoluene, and pentabromoethylbenzene. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:118556-118566. [PMID: 37917263 PMCID: PMC10697972 DOI: 10.1007/s11356-023-30566-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 10/16/2023] [Indexed: 11/04/2023]
Abstract
Hexabromobenzene (HBB), pentabromotoluene (PBT), and pentabromoethylbenzene (PBEB) are current-use brominated flame retardants (cuBFRs) which have been repeatedly detected in environmental samples. Since information on hydroxylated transformation products (OH-TPs) was scarcely available, the three polybrominated compounds were UV irradiated for 10 min in benzotrifluoride. Fractionation on silica gel enabled the separate collection and identification of OH-TPs. For more insights, aliquots of the separated OH-TPs were UV irradiated for another 50 min (60 min total UV irradiation time). The present investigation of polar UV irradiation products of HBB, PBT, and PBEB was successful in each case. Altogether, eight bromophenols were detected in the case of HBB (three Br3-, four Br4-, and one Br5-isomer), and nine OH-TPs were observed in the case of PBT/PBEB (six Br3- and three Br4-congeners). In either case, Br➔OH exchange was more relevant than H➔OH exchange. Also, such exchange was most relevant in meta- and ortho-positions. As a further point, and in agreement with other studies, the transformation rate decreased with decreasing degree of bromination. UV irradiation of HBB additionally resulted in the formation of tri- and tetrabrominated dihydroxylated compounds (brominated diphenols) that were subsequently identified. These dihydroxylated transformation products were found to be more stable than OH-TPs.
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Affiliation(s)
- Alexandra Klimm
- University of Hohenheim, Institute of Food Chemistry (170b), Garbenstraße 28, D-70599, Stuttgart, Germany
| | - Walter Vetter
- University of Hohenheim, Institute of Food Chemistry (170b), Garbenstraße 28, D-70599, Stuttgart, Germany.
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4
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Du X, Li H, Liang J, Wang R, Huang K, Hayat W, Cai L, Tao X, Dang Z, Lu G. Hydrogen-Donor-Controlled Polybrominated Dibenzofuran (PBDF) Formation from Polybrominated Diphenyl Ether (PBDE) Photolysis in Solutions: Competition Mechanisms of Radical-Based Cyclization and Hydrogen Abstraction Reactions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7777-7788. [PMID: 37115742 DOI: 10.1021/acs.est.2c08003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Polybrominated dibenzofurans (PBDFs) are characteristic dioxin-like products of polybrominated diphenyl ether (PBDE) photolysis. In this study, competition mechanisms of radical-based cyclization and hydrogen abstraction reactions are proposed in PBDF formation. Commonly, the ortho C-Br bond dissociation during photolysis generates aryl radicals, which undergo intramolecular cyclization to form PBDFs or hydrogen abstraction with hydrogen donors (such as organic solvents and water) to form lower brominated PBDEs. By using 2,4,4'-tribromodiphenyl ether (BDE-28) as the model reactant, the experimental PBDF formation ratios in various solutions are explained quantitatively by the calculated rate constants of cyclization and hydrogen abstraction reactions using the density functional theory (DFT) method. The solvent effect of pure and mixed solvents on PBDF formation is illustrated successfully. The structure-related hydrogen donation ability for hydrogen abstraction controls the bias of competition reactions and influences PBDF formation. Water resulted to be the most significant generation of PBDFs. Fulvic and humic acid display higher hydrogen donation ability than small-molecule organics due to the partitioning effect in aqueous solution. Quantitative structure-activity relationship (QSAR) models of the calculated rate constants for 512 cyclization and 319 hydrogen abstraction reactions using 189 PBDEs as the initial reactants in water are established, revealing the high risk of PBDF formation in aqueous solution.
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Affiliation(s)
- Xiaodong Du
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Haoliang Li
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Jiahao Liang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Rui Wang
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Kaibo Huang
- School of Ecology and Environment, Hainan University, Haikou 570228, China
| | - Waseem Hayat
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Limiao Cai
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Xueqin Tao
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, China
- Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, China
| | - Guining Lu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou 510006, China
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5
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Lin M, Ma S, Tang J, Yu Y, Li G, Fan R, Zhang G, Mai B, An T. Polybrominated diphenyl ethers and bromophenols in paired serum, hair, and urine samples of e-waste dismantlers: Insights into hair as an indicator of endogenous exposure. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 871:161980. [PMID: 36739029 DOI: 10.1016/j.scitotenv.2023.161980] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/28/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are important pollutants during dismantling activities of electronic waste (e-waste) in China due to its large production and usage. Bromophenols (BPs), which are a kind of flame retardants and diphenyl ether bond cleavage metabolites of PBDEs, are often neglected in the assessment of human exposure to e-waste. Herein, 22 PBDEs and 19 BPs were determined in paired serum, hair, and urine samples collected from workers and residents of a typical e-waste dismantling site in southern China. Both PBDE and BP congeners were more frequently detected in hair than serum and urine samples. The medians of ΣPBDEs and ΣBPs were 350 and 547 ng/g dw in hair internal (hair-In) of occupational population, respectively, which were significantly higher than non-occupational population. However, a non-significant difference was found in levels of ΣPBDEs and ΣBPs in serum and urine between occupational and non-occupational populations, suggesting that hair analysis could easily differentiate between the exposure intensities of PBDEs and BPs to populations than serum and urine analyses. Moreover, levels of BPs in hair-In were 1-2 orders of magnitude higher than those in hair external (hair-Ex), while a non-significant difference was found in the levels of PBDEs. This result indicated that BPs might have originated from endogenous contribution. Notably, as the predominant congeners, the level of 2,4,6-tribromophenol (2,4,6-TBP) in hair-In was 3-8 times higher than that of BDE-209, while level of 2,4,6-TBP in hair-Ex was 1-3 times lower than that of BDE-209. Furthermore, in vivo experiments performed on Sprague-Dawley rats following a 28-day oral treatment with BDE-209 and 2,4,6-TBP verified that endogenous accumulation of 2,4,6-TBP in hair could be attributed to the metabolism of BDE-209 and exposure to 2,4,6-TBP. In conclusion, compared with PBDEs, biomonitoring phenolic compounds or metabolites with hair could better reflect human endogenous exposure.
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Affiliation(s)
- Meiqing Lin
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China; State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Shengtao Ma
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jian Tang
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Yingxin Yu
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Guiying Li
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Ruifang Fan
- Guangdong Provincial Engineering Technology Research Center for Drug and Food Biological Resources Processing and Comprehensive Utilization, School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Guoxia Zhang
- Department of Environmental Health, Guangdong Provincial Key Laboratory of Tropical Disease Research, School of Public Health, Southern Medical University, Guangzhou 510515, China
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Taicheng An
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
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6
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Gribble GW. Naturally Occurring Organohalogen Compounds-A Comprehensive Review. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2023; 121:1-546. [PMID: 37488466 DOI: 10.1007/978-3-031-26629-4_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/26/2023]
Abstract
The present volume is the third in a trilogy that documents naturally occurring organohalogen compounds, bringing the total number-from fewer than 25 in 1968-to approximately 8000 compounds to date. Nearly all of these natural products contain chlorine or bromine, with a few containing iodine and, fewer still, fluorine. Produced by ubiquitous marine (algae, sponges, corals, bryozoa, nudibranchs, fungi, bacteria) and terrestrial organisms (plants, fungi, bacteria, insects, higher animals) and universal abiotic processes (volcanos, forest fires, geothermal events), organohalogens pervade the global ecosystem. Newly identified extraterrestrial sources are also documented. In addition to chemical structures, biological activity, biohalogenation, biodegradation, natural function, and future outlook are presented.
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Affiliation(s)
- Gordon W Gribble
- Department of Chemistry, Dartmouth College, Hanover, NH, 03755, USA.
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7
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Synthesis and evaluation of hydroxy- and dihydroxy brominated benzenes, methyl- and ethylbenzenes: potential metabolites of current-use brominated flame retardants. J Chromatogr A 2022; 1673:463109. [DOI: 10.1016/j.chroma.2022.463109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 11/17/2022]
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8
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Michałowicz J, Włuka A, Bukowska B. A review on environmental occurrence, toxic effects and transformation of man-made bromophenols. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 811:152289. [PMID: 34902422 DOI: 10.1016/j.scitotenv.2021.152289] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/18/2021] [Accepted: 12/05/2021] [Indexed: 06/14/2023]
Abstract
Brominated phenols (BPs) of anthropogenic origin are aromatic substances widely used in the industry as flame retardants (FRs) and pesticides as well as the components of FRs and polymers. In this review, we have focused on describing 2,4-dibromophenol (2,4-DBP), 2,4,6-tribromophenol (2,4,6-TBP) and pentabromophenol (PBP), which are the most commonly used in the industry and are the most often detected in the air, aquatic and terrestrial ecosystems and the human body. This review describes human-related sources of these BPs that influence their occurrence in the environment (atmosphere, surface water, sediment, soil, biota), indoor air and dust, food, drinking water and the human organism. Data from in vitro and in vivo studies showing 2,4-DBP, 2,4,6-TBP and PBP toxicity, including their estrogenic activity, effects on development and reproduction, perturbations of cellular redox balance and cytotoxic action have been described. Moreover, the processes of BPs transformation that occur in human and other mammals, plants and bacteria have been discussed. Finally, the effect of abiotic factors (e.g. UV irradiation and temperature) on BPs conversion to highly toxic brominated dioxins and brominated furans as well as polybrominated biphenyls and polybrominated diphenyl ethers has been presented.
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Affiliation(s)
- Jaromir Michałowicz
- University of Lodz, Faculty of Biology and Environmental Protection, Department of Biophysics of Environmental Pollution, Pomorska Str. 141/143, 90-236 Lodz, Poland.
| | - Anna Włuka
- University of Lodz, Faculty of Biology and Environmental Protection, Department of Biophysics of Environmental Pollution, Pomorska Str. 141/143, 90-236 Lodz, Poland
| | - Bożena Bukowska
- University of Lodz, Faculty of Biology and Environmental Protection, Department of Biophysics of Environmental Pollution, Pomorska Str. 141/143, 90-236 Lodz, Poland
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9
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Li M, An Z, Huo Y, Jiang J, Zhou Y, Cao H, He M. Simulation degradation of bromophenolic compounds in chlorine-based advanced oxidation processes: Mechanism, microscopic and apparent kinetics, and toxicity assessment. CHEMOSPHERE 2022; 291:133034. [PMID: 34822870 DOI: 10.1016/j.chemosphere.2021.133034] [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: 10/15/2021] [Revised: 11/19/2021] [Accepted: 11/20/2021] [Indexed: 05/28/2023]
Abstract
Chlorine-based advanced oxidation processes (AOPs) have been extensively studied to remove contaminants through generating HO• and reactive chlorine species, including ClO• and Cl•. In this work, 2,4,6-tribromoanisole (246TBA) and 2,4,6-tribromophenol (246TBP) were selected as model to investigate the reaction mechanisms and micro-kinetics of brominated contaminants with HO•, ClO• and Cl• in chlorine-based AOPs. Also, the apparent degradation kinetics of two compounds were simulated at pH 3.0-9.5 under UV/H2O2, UV/chlorine and UV/NH2Cl. Calculated results showed that neutral 246TBA and 246TBP exhibited similar reactivity to HO• and ClO•, which was different from anionic 2,4,6-tribromophenolate (246TBPT): radical adduct formation (RAF) and H atom abstraction (HAA) were predominant mechanisms for the HO• and ClO• initiated reactions of 246TBA and 246TBP, while RAF and single electron transfer (SET) for 246TBPT; the reaction rate constants of 246TBA and 246TBP with HO• and ClO• were lower than 107 M-1 s-1, and such rate constants dramatically increased to 1010 M-1 s-1 once 246TBP was deprotonated to 246TBPT. The apparent degradation kinetics of 246TBA at pH 3.0-9.5 was simulated in the order of UV/NH2Cl > UV/chlorine > UV/H2O2, and UV/chlorine and UV/NH2Cl were more effective for the removal of 246TBP and 246TBPT than UV/H2O2. UV and/or Cl• dominated 246 TBA degradation under three AOPs. The main radicals mediating 246TBP and 246TBPT degradation are respectively HO• under UV/H2O2, ClO• under UV/chlorine, and HO• and Cl• under UV/NH2Cl. The transformation products of 246TBA, 246TBP and 246TBPT, especially methoxylated and hydroxylated polybrominated diphenyl ethers (MeO-PBDEs and HO-PBDEs), were still toxic pollutants.
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Affiliation(s)
- Mingxue Li
- Environment Research Institute, Shandong University, Qingdao, 266237, PR China
| | - Zexiu An
- Environment Research Institute, Shandong University, Qingdao, 266237, PR China
| | - Yanru Huo
- Environment Research Institute, Shandong University, Qingdao, 266237, PR China
| | - Jinchan Jiang
- Environment Research Institute, Shandong University, Qingdao, 266237, PR China
| | - Yuxin Zhou
- Environment Research Institute, Shandong University, Qingdao, 266237, PR China
| | - Haijie Cao
- Institute of Materials for Energy and Environment, School of Materials Science and Engineering, Qingdao University, Qingdao, 266071, PR China
| | - Maoxia He
- Environment Research Institute, Shandong University, Qingdao, 266237, PR China.
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10
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Cao Y, Gao Y, Hu X, Zeng Y, Luo X, Li G, An T, Mai B. Insight into phototransformation mechanism and toxicity evolution of novel and legacy brominated flame retardants in water: A comparative analysis. WATER RESEARCH 2022; 211:118041. [PMID: 35030361 DOI: 10.1016/j.watres.2022.118041] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/30/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
The novel brominated flame retardants (NBFRs) have become widespread as a consequence of the prohibition on the use of polybrominated diphenyl ethers (PBDEs). However, the transformation mechanism and potential environmental risk are largely unclear. In this study, we have explored the phototransformation behavior of the most abundant NBFRs, 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) in water under ultraviolet (UV) irradiation. Meanwhile, the legacy 2,2',4,4',6,6'-hexabromodiphenyl ether (BDE155) with similar structure was investigated contrastively. Results show that novel BTBPE is more persistent than legacy BDE155, with nearly four times slower photodegradation rate constants (0.0120 min-1and 0.0447 min-1, respectively). 18 products are identified in the phototransformation of BTBPE. Different from the only debrominated products formed in legacy BDE155 transformation, the ether bond cleavage photoproducts (e.g. bromophenols) are also identified in novel BTBPE transformation. Compound-specific stable isotope analysis (CSIA) confirms the phototransformation mechanism is mainly via debromination accompanying with the breaking of ether bond. Computational toxicity assessment implies that transformation products of BTBPE still have the high kidney risks. Especially the bromophenols formed via the ether bond cleavage could significantly increase the health effects on skin irritation. This study emphasizes the importance of understanding the photolytic behavior and potential risks of novel NBFRs and other structurally similar analogues.
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Affiliation(s)
- Ya Cao
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanpeng Gao
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China.
| | - Xinyi Hu
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Yanhong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Xiaojun Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Guiying Li
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Taicheng An
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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11
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Fu L, Peng X, Chen Q, Ding Y, Jiang J. Photochemical degradation and debromination of bromophenols: Overlooked role of hydrated electron. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.119862] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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12
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Ren Z, Zeng Y, Luo X, Huang C, Tian Y, Gao S, Mai B. Observable carbon isotope fractionation in the photodegradation of polybrominated diphenyl ethers by simulated sunlight. CHEMOSPHERE 2021; 266:128950. [PMID: 33218726 DOI: 10.1016/j.chemosphere.2020.128950] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/03/2020] [Accepted: 11/10/2020] [Indexed: 06/11/2023]
Abstract
In the present study, carbon isotope effects were investigated during the photodegradation of polybrominated diphenyl ethers (PBDEs) by compound-specific stable isotope analysis (CSIA). Five PBDE congeners (BDE 85, 99, 100, 153 and 154) in n-hexane were individually exposed to simulated sunlight for as long as 15 h, except for BDE 100 (24 h). Consecutive debromination of PBDE by photolysis in n-hexane was confirmed by the clear 13C enrichment of mother congeners and successive depletion of δ13C values for the photodegradation products with decreasing degree of bromination, which can be attributed to mass-dependent isotope fractionation. The observed variation in the isotope fractionation trends for the para-debrominated products might be linked to the different photocatalytic activities of the PBDE congeners. Higher fractionation was observed for penta-BDEs (εc=-2.2 ± 0.45‰ and -2.3 ± 0.26‰ for BDE 85 and BDE 99, respectively) compared to that for hexa-BDEs (εc=-1.7 ± 0.41‰, and -1.3 ± 0.12‰ for BDE 153 and BDE 154, respectively). Normal isotope effects (AKIE > 1) observed in our study supports the utility of CSIA for the evaluation of the photodegradation of PBDEs.
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Affiliation(s)
- Zihe Ren
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Yanhong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China.
| | - Xiaojun Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China
| | - Chenchen Huang
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Yankuan Tian
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China
| | - Shutao Gao
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China; Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, People's Republic of China
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13
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Xu H, Li Y, Lu J, Lu J, Zhou L, Chovelon JM, Ji Y. Aqueous photodecomposition of the emerging brominated flame retardant tetrabromobisphenol S (TBBPS). ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 271:116406. [PMID: 33412445 DOI: 10.1016/j.envpol.2020.116406] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/10/2020] [Accepted: 12/28/2020] [Indexed: 06/12/2023]
Abstract
As an emerging brominated flame retardant (BFR), tetrabromobisphenol S (TBBPS) has been frequently detected in the environmental media and organisms. Knowledges on the transformation and fate of TBBPS in both environment and engineering systems are essential to its ecological risk assessment. Herein, we reported the photochemical decomposition of TBBPS in aqueous solution upon 254 nm ultraviolet irradiation (UV254). Results show that TBBPS was highly photoreactive, most likely due to the presence of four ortho-bromine substituents. The molar absorption coefficient and quantum yield of TBBPS were found to be pH-dependent, with the monoanionic form being most photoreactive. A series of photoproducts were identified by solid phase extraction (SPE) combined with liquid chromatography-electrospray ionization-triple quadrupole mass spectrometry (LC-ESI(+)-MS/MS. The photolysis of TBBPS likely proceeded through photonucleophilic substitution, photoreductive debromination, and β-scission reactions. A ketocarbene, possibly derived from the lower lying excited triplet state, was proposed to be involved in the photolysis of TBBPS. Ion chromatography analysis revealed that debromination occurred quickly, and the yield of bromide (Br-) approached 100% after 90 min irradiation. The presence of SRNOM and MRNOM inhibited the photodegradation rate of TBBPS, which is likely due to the light-screening and physical quenching effects of natural organic matter (NOM). Our results reveal that photolysis is an important process for the attenuation of TBBPS in aquatic system; however, naturally occurring species such as NOM can appreciably retard the decay of TBBPS.
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Affiliation(s)
- Haiyan Xu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yueyue Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jiaxin Lu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Junhe Lu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Lei Zhou
- School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Jean-Marc Chovelon
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626, Villeurbanne, France
| | - Yuefei Ji
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, 210095, China.
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14
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Liang J, Lu G, Wang R, Tang T, Huang K, Jiang F, Yu W, Tao X, Yin H, Dang Z. The formation pathways of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) from pyrolysis of polybrominated diphenyl ethers (PBDEs): Effects of bromination arrangement and level. JOURNAL OF HAZARDOUS MATERIALS 2020; 399:123004. [PMID: 32502858 DOI: 10.1016/j.jhazmat.2020.123004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
This study presents comprehensive formation pathways of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) from the pyrolysis of polybrominated diphenyl ethers (PBDEs). A total of 23 PBDE congeners, from mono- to hepta- brominated, were selected to conduct the pyrolysis experiments. The results suggest that n-PBDEs (where n means the number of bromine substituents) can transform into n/(n-1) PBDFs and (n-1)/(n-2) PBDDs as long as they meet certain structural requirement. One single PBDE congener can only transform (if possible) specific PBDF or PBDD based on their specific brominated arrangement by direct/oxygen bridge connecting the two ortho-carbon atoms. Among all selected BDEs, we found that only 2,2',4,4',5,5'-hexaBDE (BDE-153) can transform into 2,3,7,8-tetraBDD, which is most toxic congener among these group of compounds. When the degree of bromination increased, the yield of polybromobenzene increased, while that of the PBDD/Fs decreased, suggesting that the higher PBDEs favors to break the ether bond to form polybromobenzene, while the lower PBDEs favor transformation into PBDD/Fs. We proposed that the results in this study greatly improved our understanding on the transformation of PBDD/Fs from PBDEs in the pyrolysis process.
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Affiliation(s)
- Jiahao Liang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Guining Lu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
| | - Rui Wang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Ting Tang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Kaibo Huang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Fengyu Jiang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Wenjie Yu
- School of Environmental Science and Engineering, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Xueqin Tao
- School of Environmental Science and Engineering, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Hua Yin
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China
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Wang S, Wang S, Shah S, Li L, Fang H, Hao C. A density functional theory/time-dependent density functional theory study of the structure-related photochemical properties of hydroxylated polybrominated diphenyl ethers and methoxylated polybrominated diphenyl ethers and metal ion effects. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:9297-9306. [PMID: 31916157 DOI: 10.1007/s11356-019-07538-0] [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: 07/18/2019] [Accepted: 12/25/2019] [Indexed: 06/10/2023]
Abstract
As the derivatives and structural analogs of polybrominated diphenyl ethers (PBDEs), hydroxylated polybrominated diphenyl ethers (OH-PBDEs) and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) have attracted increasing concern. However, knowledge of the photochemical behaviors of OH-PBDEs and MeO-PBDEs in water is limited. Here, we used density functional theory and time-dependent density functional theory to examine the structure-related photochemical properties of OH-PBDEs and MeO-PBDEs in water and the effects of metal ions as environmental factors. Eight 6-OH-PBDEs with 1-8 bromine substituents and eight 6-MeO-PBDEs with 1-8 bromine substituents were selected for this study. The optimized geometries of the selected congeners and their complexes with metals in the lowest excited triplet state (T1) showed that one C-Br bond moderately or significantly elongated. The elongated C-Br bond in the T1 state was shown in the ortho-position for the 6-OH-PBDE congeners and the ortho-position or the meta-position for the 6-MeO-PBDE congeners. For the selected congeners, there were significant positive linear correlations between the number of bromine atoms (NBr) and the calculated average atomic charge of bromine and maximum electronic absorbance wavelength (λmax), and a negative linear correlation between the NBr and average bond dissociation energy of C-O bonds (BDEC-O). The photoreactivities of the 6-OH-PBDEs and 6-MeO-PBDEs increased with an increase in the bromination degree with or without metal ions. The calculated average atomic charge of bromine and BDEC-O of the complexes with Mg2+/Zn2+ was higher and lower than those of the corresponding monomers, respectively, indicating that the presence of Mg2+/Zn2+ increased the photoreactivity (debromination and dissociation of C-O bond) of the selected 6-OH-PBDEs and 6-MeO-PBDEs. The effects of the coordination of Mg2+/Zn2+ may be overestimated due to their missing explicit solvation shell. These results provide vital insight into the photochemical properties of OH-PBDEs and MeO-PBDEs in water.
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Affiliation(s)
- Se Wang
- School of Environmental Science and Engineering, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
| | - Shuwen Wang
- School of Environmental Science and Engineering, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Shaheen Shah
- Department of Chemistry, Karakorum International University, Gilgit, Gilgit-Balitstan, 15100, Pakistan
| | - Longyan Li
- School of Environmental Science and Engineering, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Hao Fang
- School of Environmental Science and Engineering, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Ce Hao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, 116024, Liaoning, China
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Wang Y, Peng A, Chen Z, Jin X, Gu C. Transformation of gaseous 2-bromophenol on clay mineral dust and the potential health effect. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 250:686-694. [PMID: 31035151 DOI: 10.1016/j.envpol.2019.04.072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 03/22/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
Iron-bearing clays are ubiquitously distributed as mineral dusts in the atmosphere. Bromophenols were reported as the major products from thermal decomposition of the widely used brominated flame retardants (BFRs). However, little information is available for the reactivity of iron associated with mineral dusts to interact with the atmospheric bromophenols and the subsequent toxic effects. Herein, three common clay minerals (montmorillonite, illite and kaolinite) were used to simulate mineral dusts, and the reactions with gaseous 2-bromophenol were systematically investigated under environmentally relevant atmospheric conditions. Our results demonstrate that structural Fe(III) in montmorillonite and Fe(III) from iron oxide in illite mediated the dimerization of 2-bromophenol to form hydroxylated polybrominated biphenyl and hydroxylated polybrominated diphenyl ether. The surface reaction is favored to occur at moisture environment, since water molecules formed complex with 2-bromophenol and the reaction intermediates via hydrogen bond to significantly lower the reaction energy and promote the dimerization reaction. More importantly, the formed dioxin-like products on clay mineral dust increased the toxicity of the particles to A549 lung cell by decreasing cell survival and damaging cellular membrane and proteins. The results of this study indicate that not only mineral dust itself but also the associated surface reaction should be fully considered to accurately evaluate the toxic effect of mineral dust on human health.
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Affiliation(s)
- Yi Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, PR China
| | - Anping Peng
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, PR China
| | - Zeyou Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, PR China
| | - Xin Jin
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, PR China
| | - Cheng Gu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu, 210023, PR China.
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17
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Zhou S, Pan X, Tang Q, Zhu H, Zhou J, Zhao L, Guo J, Wang Z, Liu W, Li A. Photochemical degradation of polyhalogenated carbazoles in hexane by sunlight. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 671:622-631. [PMID: 30939315 DOI: 10.1016/j.scitotenv.2019.03.325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/20/2019] [Accepted: 03/21/2019] [Indexed: 05/28/2023]
Abstract
Polyhalogenated carbazoles (PHCZs) are a class of halogenated dibenzopyrrole, which have been increasingly detected in the environment and found to be bioaccumulative and potentially toxic. However, their environmental transformation potential is largely unknown. In this study, UV absorption spectra of carbazole (CZ) and 10 PHCZs were obtained with wavelength range 290-400 nm, and three peaks were identified in most cases with the highest occurring around 300 nm. Hexane solutions of CZ, 10 individual PHCZs, and a sediment extract containing nine other PHCZs were separately irradiated under natural sunlight in order to investigate their photodegradation kinetics and pathways. The pseudo-first-order reaction rate constants (k) of these PHCZs varied from 0.183 h-1 to 2.394 h-1, and increased exponentially with increasing numbers of chlorines and bromines in PHCZ molecules. Contribution to ln k from each bromine atom is more than doubling of that from each chlorine atom. Stepwise reduction debromination was confirmed to be one of the photodegradation mechanisms for both brominated and mixed halogenated (containing both bromine and chlorine) carbazoles. Only sporadic dechlorinated products were found during the photolysis of chlorinated carbazoles. By adopting a simplified kinetic approach, we estimated that dehalogenation contributed approximately 20% to 51% of the total loss of the parent PHCZs.
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Affiliation(s)
- Shanshan Zhou
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; School of Public Health, University of Illinois at Chicago, Chicago IL60612, United States.
| | - Xiaoxue Pan
- School of Public Health, University of Illinois at Chicago, Chicago IL60612, United States; School of Environment, Nanjing University, Nanjing 210093, China
| | - Qiaozhi Tang
- School of Public Health, University of Illinois at Chicago, Chicago IL60612, United States; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongbin Zhu
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jiayi Zhou
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Lu Zhao
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiehong Guo
- School of Public Health, University of Illinois at Chicago, Chicago IL60612, United States
| | - Zunyao Wang
- School of Environment, Nanjing University, Nanjing 210093, China
| | - Weiping Liu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - An Li
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; School of Public Health, University of Illinois at Chicago, Chicago IL60612, United States; College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
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18
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Klimm A, Brenner D, Lok B, Sprengel J, Krätschmer K, Vetter W. Photolytic Transformation Products of Decabromodiphenyl Ethane (DBDPE). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:6302-6309. [PMID: 31063365 DOI: 10.1021/acs.est.9b01231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The photolytic transformation of decabromodiphenyl ethane-a current-use brominated flame retardant and major substitute of the structurally related decabromodiphenyl ether-was investigated in different solvents (toluene, dichloromethane, chlorobenzene, and benzyl alcohol). The transformation rate followed pseudo first order kinetics, with increasing half-life ( t1/2) in the order of toluene ( t1/2 = 4.6 min), chlorobenzene ( t1/2 = 14.0 min), dichloromethane ( t1/2 = 27.9 min), and benzyl alcohol ( t1/2 ≈ 60 min). Formation and amount of transformation products varied depending on the solvent used. A detailed study of the hydrodebromination products allowed us to tentatively assign all three possible nonaBDPEs (BDPE 207, 208, and in benzyl alcohol only BDPE 206) and three predominant octaBDPE congeners (BDPE 197, 201, and 202). Next to the reported BDPEs, formation of several oxygen containing transformation products (OxyTPs), dominated by octabrominated OxyTP, was verified by GC-Orbitrap-HRMS analysis. Use of HPLC and Florisil column enabled the separation of OxyTPs and BDPEs, and the polybrominated OxyTPs were most likely tricyclic compounds with almost planar structure.
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Affiliation(s)
- Alexandra Klimm
- Institute of Food Chemistry , University of Hohenheim , Garbenstraße 28 , D-70599 Stuttgart , Germany
| | - Daniela Brenner
- Institute of Food Chemistry , University of Hohenheim , Garbenstraße 28 , D-70599 Stuttgart , Germany
| | - Bianca Lok
- Institute of Food Chemistry , University of Hohenheim , Garbenstraße 28 , D-70599 Stuttgart , Germany
| | - Jannik Sprengel
- Institute of Food Chemistry , University of Hohenheim , Garbenstraße 28 , D-70599 Stuttgart , Germany
| | - Kerstin Krätschmer
- Institute of Food Chemistry , University of Hohenheim , Garbenstraße 28 , D-70599 Stuttgart , Germany
- European Union Reference Laboratory (EU-RL) for Halogenated POPs in Feed and Food , D-79114 Freiburg , Germany
| | - Walter Vetter
- Institute of Food Chemistry , University of Hohenheim , Garbenstraße 28 , D-70599 Stuttgart , Germany
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Wang R, Tang T, Feng S, Chen X, Dang D, Huang K, Tao X, Yin H, Dang Z, Lu G. Experimental and theoretical investigations on debromination pathways of polybrominated biphenyls (PBBs) under ultraviolet light. CHEMOSPHERE 2018; 212:1-7. [PMID: 30130655 DOI: 10.1016/j.chemosphere.2018.08.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 07/29/2018] [Accepted: 08/13/2018] [Indexed: 06/08/2023]
Abstract
Polybrominated biphenyls (PBBs) are brominated flame retardants that are widely used in textiles and electronic products. Recently, many researches have been devoted to determining their concentrations in food and in the environment. Yet, their degradation behavior has been less investigated and is not well understood. Here, we have investigated the debromination pathways of PBBs by (UV) light in the case of 2,4,5-tribrominated biphenyl (PBB-29). Our investigation indicates that para-bromine substituent on PBB-29 was preferentially removed. By means of density functional theory (DFT), we found that the energies of the debromination products, the CBr bond length in the excited state (S1), the Mulliken charge of bromine in S1, and the lowest unoccupied molecular orbital (LUMO) in S1 correlated well with the debromination pathways of PBBs. Further, LUMO-based prediction of PBB debromination pathways in S1 suggests that the bromine substituent on all brominated positions (i.e. ortho-, meta- and para-) can be preferentially removed, as the debromination sequence is not based on the brominated position but on the specific brominated arrangement pattern. In addition, reductive debromination preferentially occurs on the benzene ring that has the highest number of bromine substituents. This study provided useful descriptors to predict the debromination pathways of PBBs, and the theoretical result greatly improve our understanding of photolytic debromination of PBBs.
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Affiliation(s)
- Rui Wang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Ting Tang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Siyuan Feng
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Xingwei Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
| | - Dai Dang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
| | - Kaibo Huang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Xueqin Tao
- College of Environmental Science and Engineering, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Hua Yin
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, China
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, China
| | - Guining Lu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou, 510006, China.
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Kim UJ, Oh JE. Mass-flow-based removal and transformation potentials for TBBPA, HBCDs and PBDEs during wastewater treatment processes. JOURNAL OF HAZARDOUS MATERIALS 2018; 355:82-88. [PMID: 29775881 DOI: 10.1016/j.jhazmat.2018.04.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Revised: 03/02/2018] [Accepted: 04/04/2018] [Indexed: 06/08/2023]
Abstract
At a sewage treatment plant, 27 polybrominated diphenyl ethers, 17 methoxylated brominated diphenyl ethers, nine hydroxylated brominated diphenyl ethers, three hexabromocyclododecane diastereomers, and tetrabromobisphenol A were monitored at five major treatment stages (the influent, primary settlement stage, biological reaction stage, secondary settlement stage, and the UV irradiation disinfection stage). Hexabromocyclododecanes were the dominant chemicals, contributing 40% of the total concentrations of the chemicals in the dissolved phase of the sewage. Brominated flame retardant mass flow in the wastewater was lower after than before the biological reaction stage, and more than 70% of the inflowing mass load was removed from the mainstream wastewater by becoming associated with the sludge. More than half of mass loads of parent brominated flame retardants in the wastewater were removed after the treatments, but up to 10% of the initial mass loads remained in the final effluent and was expected to be released into the aquatic environment. The hydroxylated and methoxylated brominated diphenyl ether concentrations decreased by <25%, much less than the polybrominated diphenyl ethers. It is possible that hydroxylated and methoxylated polybrominated diphenyl ethers formed through the transformation of polybrominated diphenyl ethers during the biological reactions of treatment processes.
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Affiliation(s)
- Un-Jung Kim
- Department of Civil and Environmental Engineering, Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Jeong-Eun Oh
- Department of Civil and Environmental Engineering, Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Republic of Korea.
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Liu C, Tang X, Zhou B, Jiang Y, Lv M, Zang Y, Wang Y. Is it photosensitization or photodegradation when UV-B irradiation is combined with BDE-47? Evidence from the growth and reproduction changes of rotifer Brachionus plicatilis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 628-629:562-572. [PMID: 29453184 DOI: 10.1016/j.scitotenv.2018.01.306] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 01/29/2018] [Accepted: 01/29/2018] [Indexed: 06/08/2023]
Abstract
Ecotoxicological methods were applied in the present study, and the marine rotifer Brachionus plicatilis was used as the toxic endpoint to depict what occurred when 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) was combined with solar ultraviolet-B radiation (UV-B). B. plicatilis was exposed to three different combination methods of BDE-47 and UV-B at an equal toxicity ratio, including normal rotifer co-cultured with UV-B-irradiated BDE-47 (known as Method I), UV-B-irradiated rotifer co-cultured with BDE-47 exposure (known as Method II) and normal rotifer co-cultured with the simultaneous addition of BDE-47 and UV-B irradiation (known as Method III). Acute and chronic experiments were preformed to determine the toxicity differentiation according to the growth and reproduction changes in the rotifer. Twenty-four-hour acute experiments showed that the modes of three combined methods changed from antagonism to additive, to synergistic with the concentration/dose increment, and the contribution rates of Method I and Method II to Method III were calculated by approximately 40.4% and 59.6%, respectively. Chronic exposure to either the single stressor or the combination of stressors inhibited the growth and reproduction of the rotifer, demonstrating the inhibition of the population growth rate and the decrease in the larvae production. Three combined groups presented more serious damages compared to groups with single stress exposure, and the ascending sequence of toxicity was Method I<Method II<Method III. A higher bioaccumulation of BDE-47 was found in all combined groups than BDE-47 single stress group, and bioconcentration factor (BCF) general ranked Method II<Method I<Method III. Moreover, BDE-28, photodegradation production of BDE-47, were found in groups preformed Method I and III. We thus speculated that the toxicity enhancement when BDE-47 was combined with UV-B was mainly due to photosensitization and photodegradation, and the photosensitization might be more noxious to the growth and reproduction of the rotifer.
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Affiliation(s)
- Chunchen Liu
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China
| | - Xuexi Tang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
| | - Bin Zhou
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China.
| | - Yongshun Jiang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China
| | - Mengchen Lv
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China
| | - Yu Zang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China
| | - You Wang
- Department of Marine Ecology, College of Marine Life Science, Ocean University of China, Qingdao 266003, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
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22
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Huang K, Lu G, Zheng Z, Wang R, Tang T, Tao X, Cai R, Dang Z, Wu P, Yin H. Photodegradation of 2,4,4'-tribrominated diphenyl ether in various surfactant solutions: kinetics, mechanisms and intermediates. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2018; 20:806-812. [PMID: 29664078 DOI: 10.1039/c8em00033f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Currently, photodegradation has been proven to be an important way of eliminating polybrominated diphenyl ethers (PBDEs) from the environment. However, the mechanism of PBDE photodegradation in surfactants by UV light is still unclear. In this study, 2,4,4'-tribrominated diphenyl ether (BDE-28) was selected as the target pollutant to investigate the photodegradation of PBDEs in Triton X-100 (TX-100), sodium dodecylbenzenesulfonate (SDBS) and cetyltrimethylammonium bromide (CTAB) solutions. All photolysis experiments were performed above the critical micelle concentration (CMC). The results showed that photodebromination was the major pathway of BDE-28 photodestruction in different surfactants. From 1.5 CMC to 4 CMC, the photodegradation rates of BDE-28 increased as the concentration of TX-100 increased, and the increased concentration of SDBS has a negative effect on the photodegradation rate of BDE-28 due to the light barrier of SDBS. There was no obvious change in the case of CTAB. BDE-28 was debrominated to 4,4'-dibrominated diphenyl ether (BDE-15), 4-dibrominated diphenyl ether (BDE-3) and diphenyl ether (DE), subsequently. In addition, 2,8-dibrominated dibenzofuran (2,8-BDF), 2-monobrominated dibenzofuran (2-monoBDF), and dibenzofuran (DF) were produced via an intramolecular elimination of HBr from the PBDEs that had an ortho-bromine substituent. Moreover, DF can also be formed from DE and the generated amount of DF in CTAB was higher than that generated in SDBS and TX-100. We have also detected ortho-hydroxydiphenyl and para-hydroxydiphenyl during the photodegradation process.
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Affiliation(s)
- Kaibo Huang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
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Pivnenko K, Granby K, Eriksson E, Astrup TF. Recycling of plastic waste: Screening for brominated flame retardants (BFRs). WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 69:101-109. [PMID: 28869101 DOI: 10.1016/j.wasman.2017.08.038] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/27/2017] [Accepted: 08/21/2017] [Indexed: 05/28/2023]
Abstract
Flame retardants are chemicals vital for reducing risks of fire and preventing human casualties and property losses. Due to the abundance, low cost and high performance of bromine, brominated flame retardants (BFRs) have had a significant share of the market for years. Physical stability on the other hand, has resulted in dispersion and accumulation of selected BFRs in the environment and receiving biota. A wide range of plastic products may contain BFRs. This affects the quality of waste plastics as secondary resource: material recycling may potentially reintroduce the BFRs into new plastic product cycles and lead to increased exposure levels, e.g. through use of plastic packaging materials. To provide quantitative and qualitative data on presence of BFRs in plastics, we analysed bromophenols (tetrabromobisphenol A (TBBPA), dibromophenols (2,4- and 2,6-DBP) and 2,4,6-tribromophenol (2,4,6-TBP)), hexabromocyclododecane stereoisomers (α-, β-, and γ-HBCD), as well as selected polybrominated diphenyl ethers (PBDEs) in samples of household waste plastics, virgin and recycled plastics. A considerable number of samples contained BFRs, with highest concentrations associated with acrylonitrile butadiene styrene (ABS, up to 26,000,000ngTBBPA/g) and polystyrene (PS, up to 330,000ng∑HBCD/g). Abundancy in low concentrations of some BFRs in plastic samples suggested either unintended addition in plastic products or degradation of higher molecular weight BFRs. The presence of currently restricted flame retardants (PBDEs and HBCD) identified in the plastic samples illustrates that circular material flows may be contaminated for extended periods. The screening clearly showed a need for improved documentation and monitoring of the presence of BFRs in plastic waste routed to recycling.
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Affiliation(s)
- K Pivnenko
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
| | - K Granby
- National Food Institute, Technical University of Denmark, DK-2860 Søborg, Denmark
| | - E Eriksson
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - T F Astrup
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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24
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Gallistl C, Lok B, Schlienz A, Vetter W. Polyhalogenated compounds (chlorinated paraffins, novel and classic flame retardants, POPs) in dishcloths after their regular use in households. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 595:303-314. [PMID: 28384585 DOI: 10.1016/j.scitotenv.2017.03.217] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 03/23/2017] [Accepted: 03/23/2017] [Indexed: 05/22/2023]
Abstract
Dishcloths are routinely used in the clean-up process following daily kitchen activities and are thus subject to contamination commensurate with their frequent use. Here we analyzed dishcloths for the occurrence of polyhalogenated compounds after 14days of use in household kitchens. Analysis of 19 dishcloths revealed the presence of 29 polyhalogenated contaminants with total mean/median concentrations of 6,900/3,600ng/dishcloth, respectively. The spectrum featured classic and novel halogenated flame-retardants (HFRs) like polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), decabromodiphenyl ethane (DBDPE), pentabromoethylbenzene (PBEB), chlordene plus and dechlorane plus, as well as typical chloropesticides and background contaminants (e.g. hexachlorobenzene (HCB), p,p'-dichlorodiphenyldichloroethene (p,p'-DDE), polychlorinated biphenyls (PCBs) and lindane). The individual dishcloths showed highly variable fingerprints of polyhalogenated compounds. If present, medium-chain chlorinated paraffins (MCCPs) were by far the most prominent compound class with up to 55,400ng/dishcloth. Without consideration of chlorinated paraffins, the mean concentration of other polychlorinated compounds (270ng/dishcloth) was generally one order of magnitude lower than the mean concentration of brominated flame retardants (BFRs) (1,700ng/dishcloth). Our study verified that a wide range of polyhalogenated compounds is readily available in the kitchen environment. Furthermore, dishcloths are ordinarily handled without gloves or hand protection, given the observed concentrations of polyhalogenated compounds in dishcloths, such handling may serve as an additional exposure pathway for human users. Evaluation of this thesis was supported by conduction of a dermal uptake assessment.
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Affiliation(s)
- Christoph Gallistl
- University of Hohenheim, Institute of Food Chemistry (170b), Garbenstr. 28, D-70599 Stuttgart, Germany
| | - Bianca Lok
- University of Hohenheim, Institute of Food Chemistry (170b), Garbenstr. 28, D-70599 Stuttgart, Germany
| | - Annika Schlienz
- University of Hohenheim, Institute of Food Chemistry (170b), Garbenstr. 28, D-70599 Stuttgart, Germany
| | - Walter Vetter
- University of Hohenheim, Institute of Food Chemistry (170b), Garbenstr. 28, D-70599 Stuttgart, Germany.
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25
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Gallistl C, Proctor K, Bader K, Vetter W. Synthesis of the DDT metabolite 2,4-dichloro-1-[2-chloro-1-(4-chlorophenyl)ethenyl]benzene (o-Cl-DDMU) and its detection in abiotic and biotic samples. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:16815-16828. [PMID: 28573557 DOI: 10.1007/s11356-017-9173-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 05/01/2017] [Indexed: 06/07/2023]
Abstract
Technical dichlorodiphenyltrichloroethane (DDT) has been used worldwide as a pesticide since the beginning of the 1940s. Due to its persistence, DDT residues are still ubiquitously distributed in the environment. Photochemical UV degradation has been shown to be a potent degradation path for DDT and most of the resulting photoproducts have been identified up to now. Nevertheless, in 2012, a new DDT metabolite, most likely formed photochemically from DDE, was detected in ray liver samples from Brazil, an area which is highly contaminated with DDT. This study includes photochemical generation, chemical synthesis and isolation of this compound which was verified to consist of both cis- and trans-2,4-dichloro-1-[2-chloro-1-(4-chlorophenyl)ethenyl]benzene. Both stereoisomers were resolved by gas chromatography on a polar capillary column and detected in more than 60 biotic (e.g. marine mammals, birds, human milk) and abiotic samples (fat deposits in kitchen hoods) from different areas all over the world. The stereoisomer distribution and concentrations (0.3-3.9% relative to corresponding 1,1-dichloro-2,2-bis(p-chlorophenyl) ethane (p,p'-DDE) levels) were determined by means of the synthesized analytical standard, indicating the widespread occurrence of this compound as an additional minor metabolite of DDT.
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Affiliation(s)
- Christoph Gallistl
- Institute of Food Chemistry 170b, University of Hohenheim, Garbenstr. 28, 70599, Stuttgart, Germany
| | - Katie Proctor
- Institute of Food Chemistry 170b, University of Hohenheim, Garbenstr. 28, 70599, Stuttgart, Germany
- School of Chemistry, University of Birmingham, Edgbaston, B15 2TT, Birmingham, UK
| | - Korinna Bader
- Institute of Food Chemistry 170b, University of Hohenheim, Garbenstr. 28, 70599, Stuttgart, Germany
- Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany
| | - Walter Vetter
- Institute of Food Chemistry 170b, University of Hohenheim, Garbenstr. 28, 70599, Stuttgart, Germany.
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26
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Yuan W, Lu G, Xie Y, Huang K, Wang R, Yin H, Dang Z. Effect of anthraquinone-2,6-disulfonate on the photolysis of 2,4,4'-tribromophenylphenyl ether. Photochem Photobiol Sci 2017; 16:908-915. [PMID: 28436496 DOI: 10.1039/c6pp00433d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study, we have investigated the photolysis of 2,4,4'-tribromophenylphenyl ether (BDE-28) in Triton X-100 (TX-100) solutions, and discussed the effect of anthraquinone-2,6-disulfonate (AQDS) on the photolysis of BDE-28. The effect of TX-100 on the photolysis of BDE-28 was mainly related to the concentration of TX-100. The fastest photolysis of BDE-28 was at 500 mg L-1 of the TX-100 solution, and the corresponding photolysis rate constant was 0.12 min-1. The direct photolysis rate of BDE-28 decreased from 0.17 min-1 to 0.08 min-1 and 0.12 min-1 when NaN3 and isopropanol were added, respectively. The effect of AQDS on the photolysis of BDE-28 was also mainly related to the concentration of AQDS. When the concentration of AQDS was 0.6 μM, it has a slight influence in promoting the photodegradation of BDE-28; as the AQDS concentrations increased, the suppressing effect was more obvious. AQDS can inhibit the photolysis of BDE-28. Photolysis kinetics and quenching reactions illustrated that BDE-28 can produce a photosensitization reaction in TX-100 solutions, and the effects of AQDS on the photolysis of BDE-28 were mainly dominated by inhibition. In addition to its light shielding effect, AQDS can also combine with BDE-28 and anti-oxidation to inhibit the photolysis of BDE-28. We found that the degradation pathway of BDE-28 was mainly based on de-bromination, and the ions at para positions were preferentially debrominated.
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Affiliation(s)
- Wei Yuan
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
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27
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Zhao HX, Jiang JQ, Wang YL, Xie Q, Qu BC. Phototransformation of 2,4,6-tribromophenol in aqueous solution: Kinetics and photolysis products. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2017; 52:45-54. [PMID: 27726494 DOI: 10.1080/10934529.2016.1229926] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this research, we studied the phototransformation of 2,4,6-tribromophenol (TBP) by UV irradiation in aqueous solution. Effects of typical environmental factors (i.e., pH and the initial concentration of TBP, Fe3+ and NO2-) were also investigated. Results showed that the transformation process followed pseudo-first-order kinetics. The transformation rate constant of TBP decreased with increasing initial concentration and increased with increasing Fe3+ and NO2- concentrations as well as increasing pH. Ten photoproducts were tentatively identified after irradiation of TBP, according to HPLC-LTQ-Orbitrap MS and GC/MS analysis. Among them, two dihydroxylated dibromobenzene compounds (di-OH-DBB) were found to be predominant over the reaction time, indicating that hydrodebromination of TBP could be the main phototransformation mechanism. In addition, the identification of eight OH-PBDEs and di-OH-PBBs suggested that photodimerization might also be a reaction pathway for TBP photochemical reactions.
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Affiliation(s)
- Hong X Zhao
- a Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) , School of Environmental Science and Technology, Dalian University of Technology , Dalian , China
| | - Jing Q Jiang
- a Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) , School of Environmental Science and Technology, Dalian University of Technology , Dalian , China
| | - Yan L Wang
- a Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) , School of Environmental Science and Technology, Dalian University of Technology , Dalian , China
| | - Qing Xie
- a Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) , School of Environmental Science and Technology, Dalian University of Technology , Dalian , China
| | - Bao C Qu
- b Dalian Institute of Food Inspection , Dalian , China
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28
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Zhang YN, Chen J, Xie Q, Li Y, Zhou C. Photochemical transformation of five novel brominated flame retardants: Kinetics and photoproducts. CHEMOSPHERE 2016; 150:453-460. [PMID: 26796587 DOI: 10.1016/j.chemosphere.2015.12.125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/27/2015] [Accepted: 12/29/2015] [Indexed: 06/05/2023]
Abstract
Many novel brominated flame retardants (NBFRs) are used as substitutes of polybrominated diphenyl ethers (PBDEs) in recent years. However, little is known about their phototransformation behavior, which may influence the environmental fate of these chemicals. In this study, photochemical behavior of five NBFRs, allyl-2,4,6-tribromophenyl ether (ATE), 2-bromoallyl-2,4,6-tribromophenyl ether (BATE), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) was investigated. Results show all the five NBFRs can undergo photochemical transformation under simulated sunlight irradiation. Quantum yields (Φ) of the five NBFRs varied from 0.012 of TTBP-TAZ in hexane to 0.091 of BTBPE in methanol. Half-lives (t1/2) relevant with solar irradiation of these NBFRs were estimated using the determined Φ, and the values are 1.5-12.0 d in summer and 17.1-165.0 d in winter. Debrominated and ether bond cleavage products were identified in the phototransformation of DPTE and BTBPE. Debromination on the phenyl is a main phototransformation pathway for DPTE, and both debromination and ether bond cleavage are main phototransformation pathways for BTBPE. This study is helpful to better understand the phototransformation behavior of the NBFRs.
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Affiliation(s)
- Ya-Nan Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Qing Xie
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yingjie Li
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Chengzhi Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
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29
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Santos MSF, Alves A, Madeira LM. Chemical and photochemical degradation of polybrominated diphenyl ethers in liquid systems - A review. WATER RESEARCH 2016; 88:39-59. [PMID: 26465809 DOI: 10.1016/j.watres.2015.09.044] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 07/24/2015] [Accepted: 09/27/2015] [Indexed: 06/05/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are brominated flame retardants which have received a great deal of attention due to their persistence, potential to bioaccumulate and possible toxic effects. PBDEs have been globally detected in humans, wildlife and environment, highlighting the urgency of looking for effective removal technologies to mitigate their spread and accumulation in the environment. Among all environmental compartments, the water has raised particular attention. This paper aims to provide information about the suitability of the main degradation processes investigated to date (photolysis, zerovalent iron and TiO2 photocatalysis) for the degradation of PBDEs in water matrices. The most relevant criteria behind the design of a system for such purpose are discussed in detail for each individual process. The comparative analysis suggests that the oxidative degradation by TiO2 is the most appropriated technology to treat waters contaminated with PBDEs because higher debromination and mineralization degrees are achieved, preventing the formation/accumulation of lower brominated PBDE congeners and promoting the cracking of aromatic cores.
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Affiliation(s)
- Mónica S F Santos
- LEPABE - Laboratory for Process, Environmental, Biotechnology and Energy Engineering, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal.
| | - Arminda Alves
- LEPABE - Laboratory for Process, Environmental, Biotechnology and Energy Engineering, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal
| | - Luis M Madeira
- LEPABE - Laboratory for Process, Environmental, Biotechnology and Energy Engineering, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal.
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30
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Gao S, Wan Y, Zheng G, Luo K, Kannan K, Giesy JP, Lam MHW, Hu J. Organobromine compound profiling in human adipose: Assessment of sources of bromophenol. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2015; 204:81-9. [PMID: 25935608 DOI: 10.1016/j.envpol.2015.04.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 04/21/2015] [Accepted: 04/22/2015] [Indexed: 05/25/2023]
Abstract
Bromophenols (BRPs) have been widely detected in human tissues, however, relative proportions from natural products and/or anthropogenic flame retardants are not clear. 21 polybrominated diphenyl ethers (PBDEs), 15 MeO/OH-PBDEs, and 10 BRPs were simultaneously quantified in adipose collected from people from New York City, USA. An in vitro assay utilizing human liver microsomes was performed for detected predominant organobromine. High concentrations of 2,4,6-triBRP and PBDEs were observed, and extremely low concentrations of naturally occurring MeO/OH-PBDEs were detected. Similar biotransformatioin rates of BRPs and MeO/OH-PBDEs indicated that the relative high concentration of 2,4,6-triBRP in humans was not of natural origin. Significant correlation observed between concentrations of 2,4,6-triBRP and BDE-209 suggested that the two chemicals may share a common source. Both 2,4,6-triBRP and BDE-209 were detected in commercial ABS resins, suggesting that plastic products made from ABS resins could be potential sources of co-exposure of the two compounds for humans.
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Affiliation(s)
- Shixiong Gao
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Yi Wan
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
| | - Guomao Zheng
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Kai Luo
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
| | - Kurunthachalam Kannan
- Wadsworth Center, New York State Department of Health and Department of Environmental Health Sciences, School of Public Health, State University of New York, Empire State Plaza, Albany, NY 12201-0509, USA
| | - John P Giesy
- Dept. Biomedical Veterinary Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5B3, Canada; Department of Zoology and Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA; Department of Biology & Chemistry and State Key Laboratory in Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, SAR, China
| | - Michael H W Lam
- Department of Biology & Chemistry and State Key Laboratory in Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, SAR, China
| | - Jianying Hu
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
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31
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Chen D, Hale RC, Letcher RJ. Photochemical and microbial transformation of emerging flame retardants: cause for concern? ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2015; 34:687-699. [PMID: 25809099 DOI: 10.1002/etc.2858] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 09/09/2014] [Accepted: 12/12/2014] [Indexed: 06/04/2023]
Abstract
Among anthropogenic chemicals, flame retardants have attracted mounting environmental concerns. In recent years, an increasing number of studies have been conducted worldwide to investigate flame-retardant sources, environmental distribution, wildlife and human exposure, and toxicity. Data generated have demonstrated that some flame-retardant substances such as polybrominated diphenyl ethers (PBDE) are persistent, bioaccumulative, and toxic to exposed organisms. However, comparatively much less attention has been paid to the mechanisms and products of environmental transformation of flame retardants. This lack of information undermines our understanding of the environmental behavior and fate of flame retardants, as well as the associated risks to environmental and human health. Photochemical and microbial transformation of flame retardants in various matrices and environmental compartments can elevate the toxicological significance of flame retardant exposure, via the formation of, for example, lesser halogenated but more bioaccumulative degradation products and toxic radicals. Such pathways raise concerns related to the environmental safety of some alternative flame retardants that are presumably safe and used to replace PBDEs. To fully assess the environmental risks, more research is needed to investigate the environmental transformation potential of emerging flame retardants including polymeric flame retardants. Enhanced analytical efforts are needed to better characterize transformation products and transient radicals. Additional mesocosm and field studies are needed to elucidate transformation kinetics and consequences under environmentally relevant conditions.
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Affiliation(s)
- Da Chen
- Cooperative Wildlife Research Laboratory and Department of Zoology, Southern Illinois University, Carbondale, Illinois, USA
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Wang S, Hao C, Gao Z, Chen J, Qiu J. Theoretical investigations on direct photolysis mechanisms of polychlorinated diphenyl ethers. CHEMOSPHERE 2014; 111:7-12. [PMID: 24997893 DOI: 10.1016/j.chemosphere.2014.03.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 02/20/2014] [Accepted: 03/07/2014] [Indexed: 06/03/2023]
Abstract
Polychlorinated diphenyl ethers (PCDEs) are a focus of current environmental concern as a group of ubiquitous potential persistent organic pollutants. There are still significant gaps in our knowledge concerning the photolysis mechanisms of PCDEs. In this study, the direct photolysis mechanisms of PCDEs were investigated by density functional theory. The direct photolysis of PCDEs has three potential reaction pathways including photodechlorination, C-O bond photodissociation, and PCDFs formation. Taking a representative PCDE (i.e., CDE8) for example, we found that C-Cl bond dissociation is the rate-determining step for the photodechlorination. Chlorobenzene is predicted to be photoproduct of CDE8 through the photodissociation of the C-O bond. Furthermore, the calculated mean bond dissociation energies of both C-Cl and C-O bonds of 20 PCDEs decrease with the increased degree of chlorination. It is also found that the photoactivity of PCDEs increases with an increase of chlorination degree by evaluating the average charge of Cl atoms and mean bond dissociation energies of C-Cl and C-O bonds from reaction thermodynamics. Our findings provided a new insight into the mechanisms of direct photolysis of PCDEs, which may be useful in the future in utilizing quantum chemistry calculation in investigating the behavior and fate of organic pollutants in the environment.
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Affiliation(s)
- Se Wang
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Ce Hao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China.
| | - Zhanxian Gao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jieshan Qiu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian 116024, China
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Rodenburg LA, Meng Q, Yee D, Greenfield BK. Evidence for photochemical and microbial debromination of polybrominated diphenyl ether flame retardants in San Francisco Bay sediment. CHEMOSPHERE 2014; 106:36-43. [PMID: 24485321 DOI: 10.1016/j.chemosphere.2013.12.083] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 12/03/2013] [Accepted: 12/30/2013] [Indexed: 06/03/2023]
Abstract
Brominated diphenyl ethers (BDEs) are flame retardant compounds that have been classified as persistent organic pollutants under the Stockholm Convention and targeted for phase-out. Despite their classification as persistent, PBDEs undergo debromination in the environment, via both microbial and photochemical pathways. We examined concentrations of 24 PBDE congeners in 233 sediment samples from San Francisco Bay using Positive Matrix Factorization (PMF). PMF analysis revealed five factors, two of which contained high proportions of congeners with two or three bromines, indicating that they are related to debromination processes. One of the factors included PBDE 15 (4,4'-dibromo diphenyl ether, comprising 20% of the factor); the other included PBDE 7 (2,4-dibromo diphenyl ether; 12%) and PBDE 17 (2,2',4-tribromo diphenyl ether; 16%). The debromination processes that produce these congeners are probably photochemical debromination and anaerobic microbial debromination, although other processes could also be responsible. Together, these two debromination factors represent about 8% of the mass and 13% of the moles of PBDEs in the data matrix, suggesting that PBDEs undergo measurable degradation in the environment.
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Affiliation(s)
- Lisa A Rodenburg
- Department of Environmental Sciences, Rutgers University, 14 College Farm Road, New Brunswick, NJ 08901, United States.
| | - Qingyu Meng
- School of Public Health, Rutgers University, Piscataway, NJ 08854, United States
| | - Don Yee
- San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804, United States
| | - Ben K Greenfield
- San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804, United States
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Bendig P, Lehnert K, Vetter W. Quantification of bromophenols in Islay whiskies. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:2767-2771. [PMID: 24605764 DOI: 10.1021/jf405006e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Two single malt whiskies from the Scottish island Islay, i.e., Laphroiag and Lagavulin, are characterized by an iodine-like flavor associated with marine environments. In this study we investigated if this flavor impression could be due to bromophenols which are character impact compounds of marine fish and shrimps. In this study we developed a method suited for the determination of dibromo- and tribromophenols in whisky. Aliquots were O-acetylated, and quantification was carried out with gas chromatography with electron-capture negative ion mass spectrometry (GC/ECNI-MS). Both Islay whiskies contained more than 400 ng/L bromophenols with 2,6-dibromophenol being the most relevant homologue (>300 ng/L, respectively). These concentrations are at least 1 order of magnitude higher than the taste threshold of 2,6-dibromophenol in water. A third Islay whisky, Bowmore, contained ∼100 ng/L bromophenols while seventeen other whiskies from other regions in Scotland as well as from the USA, Ireland, and Germany contained at least 1 order of magnitude less than the two whiskies with the marine taste. Accordingly, bromophenols may contribute to the marine flavor and taste of Laphroaig and Lagavulin.
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Affiliation(s)
- Paul Bendig
- Institute of Food Chemistry (170b), University of Hohenheim , Garbenstrasse 28, D-70599 Stuttgart, Germany
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Widespread occurrence of polyhalogenated compounds in fat from kitchen hoods. Anal Bioanal Chem 2013; 405:7485-96. [DOI: 10.1007/s00216-013-7194-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/14/2013] [Accepted: 06/28/2013] [Indexed: 10/26/2022]
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