Polychlorinated biphenyls and organochlorine pesticides in surface sediments from Shantou Bay, China: Sources, seasonal variations and inventories.

Sediments from Shantou Bay, China, were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) for the first time. The concentrations of PCBs and OCPs were 0.54-55.5ngg and 2.19-16.9ngg (dry weight), respectively. Source identification showed that tri-CBs and penta-CBs were manufactured and used in the last century, while usage of antifouling paint might still serve as a significant source of sediment DDT. Concentrations of PCBs and HCHs significantly (p<0.05) increased after wet season, suggesting that atmospheric deposition and surface runoff played an important role in distribution of historical pollutants. Additionally, the adverse biological effects could occasionally occur for DDT in sediments. The mass inventories were preliminarily calculated for PCBs (90.1ngcm and 0.09tons) and OCPs (61.8ngcm and 0.062tons) in Shantou Bay, while as part of the "reservoir" of organochlorine compounds to the global ocean, its role cannot be neglected.