Browsing by Author "Zhu, Chaofei"

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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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    Polychlorinated biphenyls and hexachlorocyclohexanes in sediments and fish species from the Napoleon Gulf of Lake Victoria, Uganda
    (Science of the Total Environment, 2014) Ssebugere, Patrick; Sillanpää, Mika; Kiremire, Bernard T.; Kasozi, Gabriel N.; Wang, Pu; Sojinu, Samuel O.; Otieno, Peter O.; Zhu, Nali; Zhu, Chaofei; Zhang, Haidong; Shang, Hongtao; Ren, Daiwei; Li, Yingming; Zhang, Qinghua; Jiang, Guibin
    Polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) were analyzed in surface sediments (b30 cm depth) and two fish species: Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus). The samples were collected from the Napoleon Gulf on the northern shore of Lake Victoria. The analysis was done using a gas chromatograph (GC) coupled to a high resolution mass spectrometer for PCBs and a GC equipped with an electron capture detector for HCHs. Total (Σ) PCBs in the muscles of fish varied widelywith mean values ranging from41 to 670 pg g−1 lipidweight (lw). The PCB levels in L. niloticuswere significantly greater than those in O. niloticus. The large variability observed in the datawas attributed to differences in feeding habits and trophic levels. While O. niloticus is a filter-eating fish species feeding mainly on phytoplankton and zooplankton, L. niloticus have predatory feeding behaviors and prefer a diet of live fish and, therefore, are more prone to bioaccumulate contaminants. The mean PCB concentrations in the sediments varied from 362 to 848 pg g−1 dry weight. Variations in PCB levels were observed from one study site to another, this was attributed to the nature and particle size of the sediments. HCH isomers were detected in fish at mean concentrations of up to 45,900 pg g−1 lw. The PCB and HCH concentrations were lower than those from previous studies elsewhere in literature and were below the maximum residue limits set by the European Commission and FAO/WHO Codex Alimentarius Commission, implying that the fish was fit for human consumption.
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    Polychlorinated biphenyls in sediments and fish species from the Murchison Bay of Lake Victoria, Uganda
    (Science of the Total Environment, 2014) Ssebugere, Patrick; Sillanpää, Mika; Wang, Pu; Li, Yingming; Kiremire, Bernard T.; Kasozi, Gabriel N.; Zhu, Chaofei; Ren, Daiwei; Zhu, Nali; Zhang, Haidong; Shang, Hongtao; Zhang, Qinghua; Jiang, Guibin
    Polychlorinated biphenyls (PCBs) were determined in sediments and two fish species collected from the Murchison Bay in Lake Victoria, using high resolution gas chromatography coupled to a high resolution mass spectrometer. Total PCB concentrations (Σ18PCBs) varied widely with mean values ranging from 777 to 4325 pg g−1 dry weight (dw) for sediments and 80 to 779 pg g−1 wet weight (ww) for fish. The PCB levels in the sediments were significantly higher at the station closest to Nakivubo channel, presumably due to effluents discharged by the channel, which may contain domestically produced commercial PCB mixtures. For fish, the concentrations in Nile perch (Lates niloticus) were significantly greater than those in Nile tilapia (Oreochromis niloticus) at all study stations, possibly due to dietary differences among species. World Health Organization-toxic equivalents (WHO2005-TEQs) for the dioxin-like PCBs were 0.04–0.64 pg g−1 dw and 0.01–0.39 pg g−1 ww for sediments and fish, respectively. The non-ortho PCBs exhibited the highest contribution to the Σ12TEQs (N75%) compared to themono-ortho PCBs in both fish species. The TEQs in the present study were lower than many reported worldwide in literature for fish and were within the permissible level recommended by the European Commission, implying that the fish did not pose health hazards related to PCBs to the consumers.
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    Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polybrominated diphenyl ethers in sediments and fish species from the Murchison Bay of Lake Victoria, Uganda
    (Science of the total environment, 2014) Ssebugere, Patrick; Sillanpää, Mika; Wang, Pu; Li, Yingming; Kiremire, Bernard T.; Kasozi, Gabriel N.; Zhu, Chaofei; Ren, Daiwei; Shang, Hongtao; Zhang, Qinghua; Jiang, Guibin
    Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs) were analyzed in sediments and fish from the Murchison Bay of Lake Victoria by high resolution gas chromatography/ high resolution mass spectrometry (HRGC/HRMS). Average concentrations of total (Σ) PCDD/Fs and ΣPBDEs in sediments ranged from 68.8 to 479 pg g−1 dry weight (dw) and 60.8 to 179 pg g−1 dw, respectively. Contamination levels of sedimentary PCDD/Fs and PBDEs were low to moderate compared to other urbanized regions worldwide. The concentrations in different fish species (Nile perch; Lates niloticus and Nile tilapia; Oreochromis niloticus) were 5.32 to 49.0 pg g−1 wet weight (ww) for PCDD/Fs and 59.3 to 495 pg g−1 ww for PBDEs. Higher concentrations of the pollutants were found in L. niloticus than O. niloticus, which could be attributed to species differences in feeding habits and lifestyles. World Health Organization-toxic equivalents (WHO2005-TEQs) for PCDD/Fs ranged from 0.08 to 0.33 pg TEQ g−1 dw and 0.001–0.14 pg TEQ g−1 ww in sediments and fish, respectively. The TEQ values were lowcompared to the data for fresh water fish reported in literature andwithin a permissible level of 3.5 pg g−1wwrecommended by the European Commission. Based on the Commission set value and minimum risk level criteria formulated by the Agency for Toxic Substances and Disease Registry, the fish from the Murchison Bay was fit for human consumption.
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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.