PT11 Contaminant Bioavailability
Exhibit Hall
8:00 AM - Tuesday, 11 November 2003
(PT179) Concentrations and accumulation profiles of organochlorine contaminants in soils, sediments and wildlife from Lake Tai and Hangzhou Bay, China.
Nakata, H.1, Hirakawa, Y.1, Kawazoe, M.1, Abe, S.1, Kitano, T.1, Shimada, H.1, Arizono, K.2, Nakabo, T.3, Li, W.4, Ding, X.4, 1 Kumamoto University, Japan2 Kumamoto Preferectural University, Japan3 Kyoto University, Japan4 Shanghai Institute of Planned Parenthood Research, China
ABSTRACT- Contamination by persistent organochlorines (OCs), such as DDTs, hexachlorocyclohexane (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) and polychlorinated biphenyls (PCBs) were examined in 12 soils, 23 sediments, 30 fishes, 7 crustaceans and 3 birds collected from marine and freshwater ecosystems in China during 1999 and 2001. OCs were detected in all samples analyzed in this study. DDT and its metabolites were predominant contaminants in most of soils, sediments and organisms. The highest concentrations of DDTs (several ppm wet wt.) were found in birds (thick-billed reed warbler) from Lake Tai, suggesting the bioaccumulation of this pesticide through food chains. Concentrations of DDTs in marine fishes from Hangzhou Bay (1,800±840 ng/g lipid wt.) were higher than those of freshwater fishes in Lake Tai (860±440 ng/g). A concentration ratio of p,p′-DDT to total DDTs were significantly greater in marine fishes (38±15 %) than those of freshwater fishes (1.3±1.0 %). Elevated concentrations of DDTs were also found in sediments of Hangzhou Bay. These results suggest the possibility of recent release of DDTs around the coastal environment in China, although usage of DDTs have been officially banned in 1993. HCH concentrations in Lake Tai fishes were 69±11 ng/g lipid wt., which were three times greater than those in coastal fishes from Hangzhou Bay (18±10 ng/g). 
-HCH was the dominant isomer in both marine and freshwater fishes and crustaceans.
Key words: sediment, persistent organochlorines, wildlife, China