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Wei Zhang - One of the best experts on this subject based on the ideXlab platform.
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the reproductive responses of earthworms eisenia fetida exposed to nanoscale zero valent iron nzvi in the presence of Decabromodiphenyl Ether bde209
Environmental Pollution, 2017Co-Authors: Jun Liang, Xiaoqian Xia, Ling Yuan, Wei Zhang, Kuangfei Lin, B ZhouAbstract:Abstract Reproductive toxicity of nanoscale zero-valent iron (nZVI) along with coexisting Decabromodiphenyl Ether (BDE209) to earthworm Eisenia fetida (E. fetida) remains unknown. In the present study, the reproductive responses of E. fetida exposed to 100, 500 and 1000 mg kg−1 of nZVI showed a significant (P
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treatment of Decabromodiphenyl Ether bde209 contaminated soil by solubilizer enhanced electrokinetics coupled with zvi prb
Environmental Science and Pollution Research, 2017Co-Authors: Dongdong Wen, Xing Chen, Wei ZhangAbstract:Decabromodiphenyl Ether (BDE209) is a typical soil contaminant released from e-waste recycling sites (EWRSs). Electrokinetics (EK) has been considered as an excellent treatment technology with a promising potential to effectively remove organic pollutants in soil. In this study, the treatment of BDE209-polluted soil by EK was explored. All the EK experiments were conducted under a constant voltage gradient (2 V cm−1) for 14 days. Deionized water (DI water), hydroxypropyl-β-cyclodextrin (HPCD), sodium dodecyl sulfate (SDS), and humic acid (HA) were applied as the processing fluid. The experimental results showed that all the solubilizers could effectively promote the mobility and transport of BDE209 in the soil via the electro-osmotic flow (EOF) or electromigration. The removal efficiencies achieved in S1 section were 24, 22, and 26% using HPCD, SDS, and HA as the processing fluid. However, the removal of BDE209 for the entire soil cell was not achieved until zero valence iron (ZVI) was inserted at the center of soil column as a permeable reactive barrier (PRB) or (ZVI-PRB), which enhanced the degradation of BDE209. As ZVI-PRB was installed in EK5 and EK6 experiments, the corresponding average removal efficiencies increased to 16 and 13%, respectively. Additionally, the degradation products of BDE209 analyzed by GC-MS suggested that debromination of BDE209 was the main potential degradation mechanism in the EK treatment in the presence of ZVI-PRB.
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uptake and depuration kinetics of lead pb and biomarker responses in the earthworm eisenia fetida after simultaneous exposure to Decabromodiphenyl Ether bde209
Ecotoxicology and Environmental Safety, 2015Co-Authors: Wei Zhang, Kou Liu, Lin Chen, Kuangfei LinAbstract:Lead (Pb) and BDE209 (Decabromodiphenyl Ether) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impact on earthworms of exposure to the two chemicals remains almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the uptake and toxicity of Pb in the presence of BDE209 to the earthworm Eisenia fetida. The results have demonstrated that the presence of BDE209 facilitated the release of Pb into soil porewater. Compared with exposure to Pb alone, simultaneous exposure to BDE209 significantly enhanced the Pb uptake rate at the level of p<0.05, while decreased the depuration rate, ultimately resulting in a larger bioaccumulation factor (BAF) value. Additionally, BDE209 addition reduced the antioxidant enzymatic activities [superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and glutathione-s-transferase (GST)] and total antioxidant capacity (T-AOC). The decline trend in antioxidant enzymatic activities and T-AOC might explain an increase in lipid peroxidation reflected by the observed augment in malondialdehyde (MDA) level. Moreover, a biomarker of the lysosomal membrane stability, measured by neutral red retention time (NRRT), was also investigated. The NRRT obviously declined in the joint presence of BDE209, indicating a distinct time–response relationship. The results of these observations have provided a basic understanding of the potential eco-toxicological effects of joint heavy metal and BDE209 exposure on terrestrial invertebrates in a multi-contamination context of ecosystems.
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ecotoxicological effects of Decabromodiphenyl Ether and cadmium contamination on soil microbes and enzymes
Ecotoxicology and Environmental Safety, 2012Co-Authors: Wei Zhang, Meng Zhang, Bang Xiong, Changzheng Cui, Kuangfei LinAbstract:Abstract The ecotoxicological effects of Decabromodiphenyl Ether (BDE209) and cadmium (Cd) contamination on soil culturable microbial population, enzyme activity and bacterial community structure were investigated. Results of the indoor incubation test runs performed on many series of control and contaminated soil samples have demonstrated some notable toxic effects due to long term exposure to either or both contaminants. The two contaminants produced notable yet different toxic effects on the test microbes; the population of the exposed species generally declined according to certain dose–response relationships. The soil culturable microbial population and enzyme activity data show that the sensitivity to one or both contaminants followed the order of: bacteria>fungi>actinomycete and urease>saccharase, respectively. The interaction between BDE209 and Cd was dependent on both the exposure dose and time and that the joint toxic effects were synergistic, antagonistic or additive. The PCR-DGGE analysis data of species composition and richness suggest the synergistic combined effects on bacterial community structure during the 30 d exposure. Pseudomonas tuomuerensis strain CCM 7280 and Pseudomonas alcaliphila strain AL15-21 were enriched, indicating these species might be major functional populations and highly tolerant. Such observations have provided the useful information of potential ecotoxicological effects of BDE209 and Cd contamination in the environment.
Kuangfei Lin - One of the best experts on this subject based on the ideXlab platform.
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the reproductive responses of earthworms eisenia fetida exposed to nanoscale zero valent iron nzvi in the presence of Decabromodiphenyl Ether bde209
Environmental Pollution, 2017Co-Authors: Jun Liang, Xiaoqian Xia, Ling Yuan, Wei Zhang, Kuangfei Lin, B ZhouAbstract:Abstract Reproductive toxicity of nanoscale zero-valent iron (nZVI) along with coexisting Decabromodiphenyl Ether (BDE209) to earthworm Eisenia fetida (E. fetida) remains unknown. In the present study, the reproductive responses of E. fetida exposed to 100, 500 and 1000 mg kg−1 of nZVI showed a significant (P
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uptake and depuration kinetics of lead pb and biomarker responses in the earthworm eisenia fetida after simultaneous exposure to Decabromodiphenyl Ether bde209
Ecotoxicology and Environmental Safety, 2015Co-Authors: Wei Zhang, Kou Liu, Lin Chen, Kuangfei LinAbstract:Lead (Pb) and BDE209 (Decabromodiphenyl Ether) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impact on earthworms of exposure to the two chemicals remains almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the uptake and toxicity of Pb in the presence of BDE209 to the earthworm Eisenia fetida. The results have demonstrated that the presence of BDE209 facilitated the release of Pb into soil porewater. Compared with exposure to Pb alone, simultaneous exposure to BDE209 significantly enhanced the Pb uptake rate at the level of p<0.05, while decreased the depuration rate, ultimately resulting in a larger bioaccumulation factor (BAF) value. Additionally, BDE209 addition reduced the antioxidant enzymatic activities [superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and glutathione-s-transferase (GST)] and total antioxidant capacity (T-AOC). The decline trend in antioxidant enzymatic activities and T-AOC might explain an increase in lipid peroxidation reflected by the observed augment in malondialdehyde (MDA) level. Moreover, a biomarker of the lysosomal membrane stability, measured by neutral red retention time (NRRT), was also investigated. The NRRT obviously declined in the joint presence of BDE209, indicating a distinct time–response relationship. The results of these observations have provided a basic understanding of the potential eco-toxicological effects of joint heavy metal and BDE209 exposure on terrestrial invertebrates in a multi-contamination context of ecosystems.
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ecotoxicological effects of Decabromodiphenyl Ether and cadmium contamination on soil microbes and enzymes
Ecotoxicology and Environmental Safety, 2012Co-Authors: Wei Zhang, Meng Zhang, Bang Xiong, Changzheng Cui, Kuangfei LinAbstract:Abstract The ecotoxicological effects of Decabromodiphenyl Ether (BDE209) and cadmium (Cd) contamination on soil culturable microbial population, enzyme activity and bacterial community structure were investigated. Results of the indoor incubation test runs performed on many series of control and contaminated soil samples have demonstrated some notable toxic effects due to long term exposure to either or both contaminants. The two contaminants produced notable yet different toxic effects on the test microbes; the population of the exposed species generally declined according to certain dose–response relationships. The soil culturable microbial population and enzyme activity data show that the sensitivity to one or both contaminants followed the order of: bacteria>fungi>actinomycete and urease>saccharase, respectively. The interaction between BDE209 and Cd was dependent on both the exposure dose and time and that the joint toxic effects were synergistic, antagonistic or additive. The PCR-DGGE analysis data of species composition and richness suggest the synergistic combined effects on bacterial community structure during the 30 d exposure. Pseudomonas tuomuerensis strain CCM 7280 and Pseudomonas alcaliphila strain AL15-21 were enriched, indicating these species might be major functional populations and highly tolerant. Such observations have provided the useful information of potential ecotoxicological effects of BDE209 and Cd contamination in the environment.
Heather M Stapleton - One of the best experts on this subject based on the ideXlab platform.
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low level exposure to the flame retardant bde 209 reduces thyroid hormone levels and disrupts thyroid signaling in fathead minnows
Environmental Science & Technology, 2013Co-Authors: Pamela D Noyes, Sean C Lema, Laura J Macaulay, Nora K Douglas, Heather M StapletonAbstract:Polybrominated diphenyl Ether (PBDE) flame retardants have been shown to disrupt thyroid hormone regulation, neurodevelopment, and reproduction in some animals. However, effects of the most heavily used PBDE, Decabromodiphenyl Ether (BDE-209), on thyroid functioning remain unclear. This study examined low-dose effects of BDE-209 on thyroid hormone levels and signaling in fathead minnows. Adult males received dietary exposures of BDE-209 at a low dose (∼3 ng/g bw-day) and high dose (∼300 ng/g bw-day) for 28 days followed by a 14-day depuration to evaluate recovery. Compared to controls, fish exposed to the low dose for 28 days experienced a 53% and 46% decline in circulating total thyroxine (TT4) and 3,5,3′-triiodothyronine (TT3), respectively, while TT4 and TT3 deficits at the high dose were 59% and 62%. Brain deiodinase activity (T4-ORD) was reduced by ∼65% at both doses. BDE-209 elevated the relative mRNA expression of genes encoding deiodinases, nuclear thyroid receptors, and membrane transporters in t...
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accumulation and debromination of Decabromodiphenyl Ether bde 209 in juvenile fathead minnows pimephales promelas induces thyroid disruption and liver alterations
Toxicological Sciences, 2011Co-Authors: Pamela D Noyes, David E Hinton, Heather M StapletonAbstract:Polybrominated diphenyl Ether (PBDE) flame retardants are known to affect thyroid hormone (TH) regulation. The TH-regulating deiodinases have been implicated in these impacts; however, PBDE effects on the fish thyroid system are largely unknown. Moreover, the liver as a potential target of PBDE toxicity has not been explored in young fish. This study measured Decabromodiphenyl Ether (BDE-209) effects on TH regulation by measuring deiodinase activity in juvenile fathead minnows (Pimephales promelas). Dietary accumulations and debromination of BDE-209 were also measured, and the morphology of thyroid and liver tissues was examined. Juvenile fathead minnows (28 days old) received a 28-day dietary treatment of BDE-209 at 9.8 ± 0.16 μg/g of food at 5% of their body weight per day followed by a 14-day depuration period in which they were fed clean food. Chemical analysis revealed that BDE-209 accumulated in tissues and was metabolized to reductive products ranging from penta- to octaBDEs with 2,2′,4,4′,5,6′-hexabromodiphenyl Ether (BDE-154) being the most accumulative metabolite. By day 28 of the exposure, rates of outer and inner ring deiodination (ORD and IRD, respectively) of thyroxine (T4) were each reduced by ∼74% among treatments. Effects on T4-ORD and T4-IRD remained significant even after the 14-day depuration period. Histological examination of treated fish showed significantly increased thyroid follicular epithelial cell heights and vacuolated hepatocyte nuclei. Enlarged biliary passageways may be the cause of the distinctive liver phenotype observed, although further testing is needed. AltogEther, these results suggest that juvenile fish may be uniquely susceptible to thyroid disruptors like PBDEs.
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photodegradation of Decabromodiphenyl Ether in house dust by natural sunlight
Environmental Toxicology and Chemistry, 2008Co-Authors: Heather M Stapleton, Nathan G DodderAbstract:: Photolytic degradation of Decabromodiphenyl Ether (BDE 209) has been observed in several matrices such as solvent/ water mixtures, sediments, and soil; however, no studies have investigated the degradation potential of BDE 209 in house dust. In the present study, both a natural and a BDE 209-spiked dust material were exposed to sunlight for 200 cumulative h. Degradation of BDE 209 was observed in both matrices but was 35% greater in the spiked dust relative to the natural dust material. The pseudo- first-order degradation rates were 2.3 x 10(-3) and 1.7 x 10(-3) per hour for the spiked and natural dust, respectively. During the 200-h exposure, as much as 38% of the original BDE 209 mass was degraded in the spiked dust, 25% of which could not be accounted for and was lost to unknown pathways and/or products. The remaining 13% was accounted for by the formation of lower brominated congeners. Debrominated products detected in the spiked dust included all three nonabrominated congeners (BDE 206, BDE 207, and BDE 208) and several octabrominated congeners (BDE 196, BDE 197, BDE 201, BDE 202, and BDE 203/200). In technical commercial octa-BDE mixtures, BDE 201 is a very small component (below detection limit to 0.8%), and BDE 202 is not detected. Therefore, the presence of these congeners in house dust may provide a marker of environmental debromination of BDE 209. The ratio of BDE 197 to BDE 201 may also be indicative of BDE 209 degradation. as the ratio of these two congeners appeared to reach a steady-state value (~1) in both exposure scenarios in the present study.
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in vivo and in vitro debromination of Decabromodiphenyl Ether bde 209 by juvenile rainbow trout and common carp
Environmental Science & Technology, 2006Co-Authors: Heather M Stapleton, Brian Brazil, David R Holbrook, Carys L Mitchelmore, Rae T Benedict, And Alex Konstantinov, Dave PotterAbstract:Decabromodiphenyl Ether (BDE 209), the major congener in the high volume industrial flame retardant mixture “DecaBDE”, has recently been shown to be metabolized by carp. To further explore this phe...
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debromination of the flame retardant Decabromodiphenyl Ether by juvenile carp cyprinus carpio following dietary exposure
Environmental Science & Technology, 2004Co-Authors: Heather M Stapleton, Robert J Letcher, Mehran Alaee, Joel E BakerAbstract:The congener 2,2‘,3,3‘,4,4‘,5,5‘,6,6‘-Decabromodiphenyl Ether (BDE 209) is the primary component in a commonly used flame retardant known as decaBDE. This flame retardant constitutes approximately 80% of the world market demand for polybrominated diphenyl Ethers (PBDEs). Because this compound is very hydrophobic (log Kow ∼ 10), it has been suggested that BDE 209 has very low bioavailability, although debromination to more bioavailable metabolites has also been suggested to occur in fish tis- sues. In the present study, juvenile carp were exposed to BDE 209 amended food on a daily basis for 60 days, fol- lowed by a 40-day depuration period in which the fate of BDE 209 was monitored in whole fish and liver tissues sepa- rately. No net accumulation of BDE 209 was observed throughout the experiment despite an exposure concentration of 940 ng/day/fish. However, seven apparent debrominated products of BDE 209 accumulated in whole fish and liver tissues over the exposure period. These debrominated metabolites of...
Damia Barcelo - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the genotoxic and physiological effects of Decabromodiphenyl Ether bde 209 and dechlorane plus dp flame retardants in marine mussels mytilus galloprovincialis
Environmental Science & Technology, 2016Co-Authors: Enrique Baron, Awantha Dissanayake, Judit Vilacano, Charlotte Crowther, James W Readman, Awadhesh N Jha, Ethel Eljarrat, Damia BarceloAbstract:Dechlorane Plus (DP) is a proposed alternative to the legacy flame retardant Decabromodiphenyl Ether (BDE-209), a major component of Deca-BDE formulations. In contrast to BDE-209, toxicity data for DP are scarce and often focused on mice. Validated dietary in vivo exposure of the marine bivalve (Mytilus galloprovincialis) to both flame retardants did not induce effects at the physiological level (algal clearance rate), but induced DNA damage, as determined by the comet assay, at all concentrations tested. Micronuclei formation was induced by both DP and BDE-209 at the highest exposure concentrations (100 and 200 μg/L, respectively, at 18% above controls). DP caused effects similar to those by BDE-209 but at lower exposure concentrations (5.6, 56, and 100 μg/L for DP and 56, 100, and 200 μg/L for BDE-209). Moreover, bioaccumulation of DP was shown to be concentration dependent, in contrast to BDE-209. The results described suggest that DP poses a greater genotoxic potential than BDE-209.
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determination of Decabromodiphenyl Ether in sediments using selective pressurized liquid extraction followed by gc nci ms
Analytical and Bioanalytical Chemistry, 2004Co-Authors: Ethel Eljarrat, Agustina De La Cal, Damia BarceloAbstract:A method based on selective pressurized liquid extraction (SPLE) followed by gas chromatography–negative ion chemical ionization-mass spectrometry (GC–NCI-MS) has been evaluated for analysis of Decabromodiphenyl Ether (PBDE-209) in sediment samples. Instrumental operating conditions such as source temperature and system pressure were optimized in the NCI-MS system, giving an instrumental detection limit of 2 pg. The limit of determination of the entire SPLE–GC–NCI-MS procedure was around 50 pg g−1 dry weight (dw), with repeatability of replicates between 4 and 21% relative standard deviation. Application of the method to 13 different river and marine sediment samples collected in Spain revealed that levels of Decabromodiphenyl Ether ranged between 2 and 132 ng g−1 dry weight.
B Zhou - One of the best experts on this subject based on the ideXlab platform.
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the reproductive responses of earthworms eisenia fetida exposed to nanoscale zero valent iron nzvi in the presence of Decabromodiphenyl Ether bde209
Environmental Pollution, 2017Co-Authors: Jun Liang, Xiaoqian Xia, Ling Yuan, Wei Zhang, Kuangfei Lin, B ZhouAbstract:Abstract Reproductive toxicity of nanoscale zero-valent iron (nZVI) along with coexisting Decabromodiphenyl Ether (BDE209) to earthworm Eisenia fetida (E. fetida) remains unknown. In the present study, the reproductive responses of E. fetida exposed to 100, 500 and 1000 mg kg−1 of nZVI showed a significant (P
