Browsing by Author "Zhu, Nali"

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    Hexabromocyclododecane in alpine fish from the Tibetan Plateau, China
    (Environmental Pollution, 2013) Zhu, Nali; Fu, Jianjie; Gao, Yan; Ssebugere, Patrick; Wang, Yawei; Jiang, Guibin
    Hexabromocyclododecanes (HBCDs) has just been listed into Stockholm Convention as a persistent organic pollutant recently. This paper studied the HBCDs in 79 wild fish from high mountain lakes and rivers of the Tibetan Plateau. ThePHBCDs in fish muscles ranged from non detectable levels to 13.7 ng/g lipid weight (lw) (mean value of 2.12 ng/g lw) with a high detection frequency of 65.8%. a-HBCD dominated among the isomers and accounted for 78.2% of the total burden. Concentrations of PHBCDs in the fish were significantly correlated with the lipid content. A decreasing trend was observed between a-HBCD and trophic level. Positive correlation was also noted between the HBCD levels in fish from lakes and the annual precipitation, and this implied the long-range atmospheric transport of HBCDs to the Tibet Plateau. This was the first work to widely explore HBCDs contamination in the aquatic ecosystems of the Tibetan Plateau.
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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.