Polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins and dibenzofurans in marine and lacustrine sediments from the Shandong Peninsula, China

Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in sediments from Bohai Sea and Yellow Sea coastal waters and lakes in Shandong Peninsula were determined. The total PCB concentrations of the measured 50 congeners (Sigma50PCBs) in the sediments ranged from 273.7 to 644.5 pg g(-1) dw (dry weight). The PCB congener profiles in the lacustrine sediments were different from those in the marine sediments. TriCBs and TetraCBs were the dominant homologues in marine sediments, whereas in the sediments from the Nansi Lakes, contributions of PCB homologues were similar. The total concentrations of 2,3,7,8-PCDD/Fs ranged from 6.2 to 27.4 pg g(-1) dw. The congener profiles of 2,3,7,8-substituted PCDD/Fs for the sediments were generally similar for both the lakes and the coastal sea areas in Shandong Peninsula. They were characterized by high OCDD, followed by 1,2,3,4,6,7,8-HpCDD and OCDF. The congener profiles of PCDD/Fs in the sediments were consistent with the profiles of main dominant PCDD/Fs in pentachlorophenol and sodium pentachlorophenate products in China. PCDD/F-TEQ ranged from 0.11 to 0.80 pg TEQg(-1) dw. The dioxin-like PCB-TEQ had concentrations ranging from 0.03 to 0.08 pg TEQ g(-1) dw, mainly from PCB126. PCBs and PCDD/Fs concentrations found in the sediments were from background to low polluted levels.

Total fluorine, extractable organic fluorine, perfluorooctane sulfonate and other related fluorochemicals in liver of Indo-Pacific humpback dolphins (Sousa chinensis) and finless porpoises (Neophocaena phocaenoides) from South China

The concentrations of 10 PFCs (perfluorinated compounds: PFOS, PFHxS, PFOSA, N-EtFOSA, PFDoDA, PFUnDA, PFDA, PFNA, PFOA, and PFHpA) were measured in liver samples of Indo-Pacific humpback dolphins (Sousa chinensis) (n=10) and finless porpoises (Neophocaena phocaenoides) (n=10) stranded in Hong Kong between 2003 and 2007. PFOS was the dominant PFC in the tissues at concentrations ranging at 26-693 ng/g ww in dolphins and 51.3-262 ng/g ww in porpoises. A newly developed combustion ion chromatography for fluorine was applied to measure total fluorine (TF) and extractable organic fluorine (EOF) in these liver samples to understand PFC contamination using the concept of mass balance analysis. Comparisons between the amounts of known PFCs and EOF in the livers showed that a large proportion (approximately 70%) of the organic fluorine in both species is of unknown origin. These investigations are critical for a comprehensive assessment of the risks of these compounds to humans and other receptors.