Browsing by Author "Chen, Zhaojing"

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    Bioconcentration and trophic transfer of polychlorinated biphenyls and polychlorinated dibenzo-p-dioxins and dibenzofurans in aquatic animals from an e-waste dismantling area in East China
    (Environmental Science: Processes & Impacts, 2015) Zhu, Chaofei; Wang, Pu; Li, Yingming; Chen, Zhaojing; Li, Wenjuan; Ssebugere, Patrick; Zhang, Qinghua; Jianga, Guibin
    Eight aquatic biota species were collected from an e-waste dismantling area in East China to investigate bioconcentration and trophic transfer of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-pdioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The mean concentrations of PCBs varied widely from 6.01 104 to 2.27 106 pg per g dry weight (dw). The P25PCB concentrations in eels were significantly higher than those in other species. The levels of PCDD/Fs changed from 8.13 pg per g dw in toads to 617 pg per g dw in stone snails. World Health Organization-toxic equivalents (WHO2005-TEQs) ranged from 2.57 to 2352 pg WHO-TEQ per g dw with a geometric mean value of 64.7 pg WHO-TEQ per g dw, which greatly exceeded the maximum levels of 4 pg per g ww set by the European Commission. The log-transferred bioconcentration factors (BCFs) of 25 PCB congeners ranged from 1.0 to 6.6, with the highest value for CB-205 in crucian carp and the lowest value for CB-11 in frog. A parabolic correlation was observed between log BCF and log Kow (R2 ¼ 0.53, p < 0.001), where the maximum value occurred at a log Kow of approximately 7. A similar correlation was also found in the plot of log BCF against the number of chlorine atoms of PCBs (R2 ¼ 0.57, p < 0.001), indicating that mediumhalogenated congeners of PCBs are more easily accumulated by aquatic biota species. There were no significant correlations between the log-transferred concentrations and trophic levels of aquatic species, suggesting that trophic magnification for PCBs and PCDD/Fs was not observed in this study.
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    Polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) in environmental samples from Ny-Ålesund and London Island, Svalbard, the Arctic
    (Chemosphere, 2015) Zhu, Chaofei; Li, Yingming; Wanga, Pu; Chen, Zhaojing; Ren, Daiwei; Ssebugere, Patrick; Zhang, Qinghua; Jiang, Guibin
    Polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs) were determined in environmental samples collected from Ny-Ålesund and London Island, Svalbard, the Arctic. Total PCB concentrations (P25PCBs) varied from 0.57 to 2.52 ng g 1 dry weight (dw) in soil, 0.30 to 1.16 ng g 1 dw in plants and 0.56 to 0.98 ng g 1 dw in reindeer dung. The non-Aroclor congener of CB-11 was predominant in most samples compared to other congeners, accounting for 16.0 ± 9.8% to theP25PCBs. TheP13PBDEs concentrations were 1.7–416, 36.7–495 and 28.1–104 pg g 1 dw in soil, plants and reindeer dung, respectively. The signature of enantioselective biotransformation was observed in all samples for chiral CB-95, whereas in parts of samples for other chiral PCBs. Bioaccumulation factors (BAFs) in six plant species varied within individual contaminant congeners and plant species, with BAFs less than 1 for PPCBs and higher than 1 forPPBDEs. BAF values decreased with increasing soil concentrations, suggesting that high background levels in soil restricted the accumulation of these contaminants by plants.
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    Trophic transfer of hexabromocyclododecane in the terrestrial and aquatic food webs from an e-waste dismantling region in East China
    (Environmental Science, 2017) Zhu, Chaofei; Wang, Pu; Li, Yingming; Chen, Zhaojing; Li, Honghua; Ssebugere, Patrick; Zhang, Qinghua; Jiang, Guibin
    Trophic transfer of hexabromocyclododecane (HBCD) was investigated in both the terrestrial and aquatic food webs from an e-waste dismantling region in East China. The mean S3HBCD concentrations in the terrestrial species varied from 0.91 (0.16–1.85) ng g 1 lipid weight (lw) in dragonflies (Pantala flavescens) to 40.3 (22.1–51.1) ng g 1 lw in rats (Rattus norvegicus). The isomeric profile indicated that a-HBCD presented a decreasing trend along the trophic level (TL) (from 97.2% to 16.3% of S3HBCDs), while g-HBCD showed a reverse trend (from 2.8% to 73.6% of S3HBCDs). The trophic magnification factor (TMF) derived from the slope of the regression line between TLs and ln-transferred S3HBCDs was 0.10, suggesting a trophic dilution of HBCD in the terrestrial food web. By contrast, in the aquatic species, S3HBCD concentrations varied from 5.02 (3.5–6.55) ng g 1 lw in apple snails (Ampullaria gigas spix) to 45.9 (14.9–67.8) ng g 1 lw in grass carps (Ctenopharyngodon idellus). a-HBCD was the dominant isomer, followed by g-HBCD in the majority of species. A positive linear relationship was observed in the plots of ln S3HBCDs versus TLs (R2 ¼ 0.81, p ¼ 0.06). The TMF for S3HBCDs was 6.36, indicating a trophic magnification of HBCD in the aquatic food web. Although these results demonstrated the distinct trophic transfer of S3HBCDs in different ecosystems, further research is needed to eliminate the uncertainty of the tendencies, due to the non-significant relationship and limited species.