scholarly journals Reductive Debromination of Polybrominated Diphenyl Ethers by Anaerobic Bacteria from Soils and Sediments

2009 ◽  
Vol 76 (3) ◽  
pp. 794-802 ◽  
Author(s):  
Lip Kim Lee ◽  
Jianzhong He
Keyword(s):  
Polybrominated Diphenyl Ethers ◽  
Diphenyl Ether ◽  
Anaerobic Bacteria ◽  
Metabolic Process ◽  
Rrna Gene ◽  
Environmental Media ◽  
Total Product ◽  
Soils And Sediments ◽  
Diphenyl Ethers ◽  
Insight Into

ABSTRACT Polybrominated diphenyl ethers (PBDEs) have attracted attention recently due to their proven adverse effects on animals and their increasing concentrations in various environmental media and biota. To gain insight into the fate of PBDEs, microcosms established with soils and sediments from 28 locations were investigated to determine their debromination potential with an octa-brominated diphenyl ether (octa-BDE) mixture consisting of hexa- to nona-BDEs. Debromination occurred in microcosms containing samples from 20 of the 28 locations when they were spiked with octa-BDE dissolved in the solvent trichloroethene (TCE), which is a potential cosubstrate for stimulating PBDE debromination, and in microcosms containing samples from 11 of the 28 locations when they were spiked with octa-BDE dissolved in nonane. Debromination products ranging from hexa- to mono-BDEs were generated within 2 months. Notably, the toxic tetra-BDEs accounted for 50% of the total product. In sediment-free culture C-N-7* amended with the octa-BDE mixture and nonane (containing 45 nM nona-BDE, 181 nM octa-BDEs, 294 nM hepta-BDE, and 19 nM hexa-BDE) there was extensive debromination of the parent compounds, which produced hexa-BDE (56 nM), penta-BDEs (124 nM), and tetra-BDEs (150 nM) within 42 days, possibly by a metabolic process. A 16S rRNA gene-based analysis revealed that Dehalococcoides species were present in 11 of 14 active microcosms. However, unknown debrominating species in some of the microcosms debrominated the octa-BDE mixture in the absence of other added halogenated electron acceptors (such as TCE). These findings provide information that is useful for assessing microbial reductive debromination of higher brominated PBDEs to less-brominated congeners, a possible source of the more toxic congeners (e.g., penta- and tetra-BDEs) detected in the environment.

Photodegradation of 2,4,4′-tribrominated diphenyl ether in various surfactant solutions: kinetics, mechanisms and intermediates

2018 ◽  
Vol 20 (5) ◽  
pp. 806-812 ◽  
Author(s):  
Kaibo Huang ◽  
Guining Lu ◽  
Zhiqiang Zheng ◽  
Rui Wang ◽  
Ting Tang ◽  
...  
Keyword(s):  
Polybrominated Diphenyl Ethers ◽  
Diphenyl Ether ◽  
Surfactant Solutions ◽  
Diphenyl Ethers

Currently, photodegradation has been proven to be an important way of eliminating polybrominated diphenyl ethers (PBDEs) from the environment.

scholarly journals Isolation of Acetobacterium sp. Strain AG, Which Reductively Debrominates Octa- and Pentabrominated Diphenyl Ether Technical Mixtures

2012 ◽  
Vol 79 (4) ◽  
pp. 1110-1117 ◽  
Author(s):  
Chang Ding ◽  
Wai Ling Chow ◽  
Jianzhong He
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Polybrominated Diphenyl Ethers ◽  
Enrichment Culture ◽  
Diphenyl Ether ◽  
Environmental Pollutants ◽  
Content Type ◽  
Diphenyl Ethers ◽  
First Time ◽  
Free Enrichment

ABSTRACTPolybrominated diphenyl ethers (PBDEs) are a class of environmental pollutants that have been classified as persistent organic pollutants since 2009. In this study, a sediment-free enrichment culture (culture G) was found to reductively debrominate octa- and penta-BDE technical mixtures to less-brominated congeners (tetra-, tri-, and di-BDEs) via apara-dominant debromination pattern for the former and a strictparadebromination pattern for the latter. Culture G could debrominate 96% of 280 nM PBDEs in an octa-BDE mixture to primarily tetra-BDEs in 21 weeks. Continuous transferring of culture G with octa-/penta-BDEs dissolved inn-nonane or trichloroethene (TCE) yielded two strains (Acetobacteriumsp. strain AG andDehalococcoidessp. strain DG) that retained debromination capabilities. In the presence of lactate but without TCE, strain AG could cometabolically debrominate 75% of 275 nM PBDEs in a penta-BDE mixture in 33 days. Strain AG shows 99% identity to its closest relative,Acetobacterium malicum. In contrast to strain AG, strain DG debrominated PBDEs only in the presence of TCE. In addition, 18 out of 19 unknown PBDE debromination products were successfully identified from octa- and penta-BDE mixtures and revealed, for the first time, a comprehensive microbial PBDE debromination pathway. As an acetogenic autotroph that rapidly debrominates octa- and penta-BDE technical mixtures,Acetobacteriumsp. strain AG adds to the still-limited understanding of PBDE debromination by microorganisms.

scholarly journals Human Excretion of Polybrominated Diphenyl Ether Flame Retardants: Blood, Urine, and Sweat Study

2017 ◽  
Vol 2017 ◽  
pp. 1-14 ◽  
Author(s):  
Shelagh K. Genuis ◽  
Detlef Birkholz ◽  
Stephen J. Genuis
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Polybrominated Diphenyl Ethers ◽  
Flame Retardants ◽  
Diphenyl Ether ◽  
Body Fluids ◽  
Urine Samples ◽  
Health Implications ◽  
Reproductive Effects ◽  
Diphenyl Ethers

Commonly used as flame retardants, polybrominated diphenyl ethers (PBDEs) are routinely detected in the environment, animals, and humans. Although these persistent organic pollutants are increasingly recognized as having serious health implications, particularly for children, this is the first study, to our knowledge, to investigate an intervention for human elimination of bioaccumulated PBDEs. Objectives. To determine the efficacy of blood, urine, and perspiration as PBDE biomonitoring mediums; assess excretion of five common PBDE congeners (28, 47, 99, 100, and 153) in urine and perspiration; and explore the potential of induced sweating for decreasing bioaccumulated PBDEs. Results. PBDE congeners were not found in urine samples; findings focus on blood and perspiration. 80% of participants tested positive in one or more body fluids for PBDE 28, 100% for PBDE 47, 95% for PBDE 99, and 90% for PBDE 100 and PBDE 153. Induced perspiration facilitated excretion of the five congeners, with different rates of excretion for different congeners. Conclusion. Blood testing provides only a partial understanding of human PBDE bioaccumulation; testing of both blood and perspiration provides a better understanding. This study provides important baseline evidence for regular induced perspiration as a potential means for therapeutic PBDE elimination. Fetotoxic and reproductive effects of PBDE exposure highlight the importance of further detoxification research.

Polybrominated diphenyl ethers in birds from Chongming Island, Yangtze estuary, China: Insight into migratory behavior

Chemosphere ◽  
2013 ◽  
Vol 91 (10) ◽  
pp. 1416-1425 ◽  
Author(s):  
Kai Huang ◽  
Kuangfei Lin ◽  
Jie Guo ◽  
Xiaoyu Zhou ◽  
Junxia Wang ◽  
...  
Keyword(s):  
Polybrominated Diphenyl Ethers ◽  
Yangtze Estuary ◽  
Migratory Behavior ◽  
Chongming Island ◽  
Diphenyl Ethers ◽  
Insight Into

scholarly journals Exposure to Polybrominated Diphenyl Ethers (PBDEs) and Hypothyroidism in Canadian Women

2016 ◽  
Vol 101 (2) ◽  
pp. 590-598 ◽  
Author(s):  
Youssef Oulhote ◽  
Jonathan Chevrier ◽  
Maryse F. Bouchard
Keyword(s):  
Thyroid Hormone ◽  
Polybrominated Diphenyl Ethers ◽  
Diphenyl Ether ◽  
Hormone Replacement ◽  
Plasma Concentrations ◽  
Reproductive Age ◽  
Age Group ◽  
Cross Sectional ◽  
Wide Range ◽  
Diphenyl Ethers

Context: Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in a wide range of products, resulting in widespread human exposure. Epidemiological studies in some populations reported exposure to PBDEs and thyroid hormone levels but little epidemiological data are available among women from the general population. Objective: The objective of the study was to examine the association of PBDEs with hypothyroidism. Design and Setting: This was a cross-sectional analysis of the 2007–2009 Canadian Health Measures Survey. Participants: A total of 745 women representative of Canadian women aged 30–79 years participated in the study. Main Outcome and Methods: We estimated the prevalence ratios (PRs) for hypothyroidism in relation to plasma concentrations of BDE-47, -99, -100, and -153 and their sum (ΣPBDEs). Women were identified as cases if they reported a doctor-diagnosed thyroid condition and underwent thyroid hormone replacement therapy (n = 90). Results: Higher plasma levels of brominated diphenyl ether (BDE)-47 and -100 and ΣPBDEs were associated with an increased prevalence of hypothyroidism. The PR for a 10-fold increase in ΣPBDEs was 1.7 (95% confidence interval [CI] 1.0, 3.0). Associations were consistently higher among women aged 30–50 years than among those 51–79 years for ΣPBDEs and the other PBDE congeners, although the interaction was significant only for BDE-100. For instance, in the younger age group, women with detectable levels of BDE-100 had a PR of 3.8 (95% CI 1.2, 12.3) compared with women with undetectable levels; the corresponding PR in the older age group was 1.2 (95% CI 0.6, 2.3). No association was observed for BDE-99 and -153. Conclusion: Plasma PBDE levels were associated with an increased prevalence of hypothyroidism in Canadian women aged 30–50 years. Although the cross-sectional design of the study limits inferences of causality, these findings have important implications, given the key role of thyroid hormones in several biological mechanisms during reproductive age.

Exposure of alveolar macrophages to polybrominated diphenyl ethers suppresses the release of pro-inflammatory products in vitro

2012 ◽  
Vol 237 (4) ◽  
pp. 429-434 ◽  
Author(s):  
Stephen R Hennigar ◽  
Jay L Myers ◽  
Anthony R Tagliaferro
Keyword(s):  
Estrogen Receptor ◽  
Alveolar Macrophages ◽  
Polybrominated Diphenyl Ethers ◽  
Diphenyl Ether ◽  
Prostaglandin E ◽  
Tnf Α ◽  
Diphenyl Ethers ◽  
The Impact

Inhalation of chemical pollutants has been associated with a reduced immune response in humans. Inhalation of dust is a major route of exposure for one endocrine-disrupting chemical and suspected xenoestrogen, polybrominated diphenyl ethers (PBDEs); however, the impact of PBDEs on immune function is unclear. The objective of this study was to investigate the action of PBDEs on cytokine and eicosanoid release by alveolar macrophages and determine whether the effects are mediated via the estrogen receptor. The production of tumor necrosis factor (TNF)- α, interleukin (IL)-6, IL-1 β, IL-10 and prostaglandin E2 (PGE2) by porcine alveolar macrophages exposed to different concentrations of the pentabrominated diphenyl ether mixture, DE-71, were measured; cells were also exposed to varying concentrations of 17 β-estradiol and the selective estrogen receptor-modulating agent, tamoxifen. Cells exposed to PBDEs released significantly less pro-inflammatory cytokines (TNF- α and IL-6) and PGE2 compared with controls; IL-1 β and IL-10 were not detected in the culture medium. Cells exposed to 17 β-estradiol released significantly less TNF- α compared with controls, an effect that was reversed by the addition of tamoxifen; tamoxifen had no effect on the inhibition of TNF- α release by PBDEs. Although the suppression of TNF- α with DE-71 was similar to that of estrogen, the inhibitory effects of DE-71 were not found to be dependent on the estrogen receptor. Findings of this study suggest that chronic exposure to PBDEs suppressed innate immunity in vitro. Whether the immunosuppressant effects of PBDEs occur in vivo, remains to be determined.

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