Distribution of PCBs at different levels of aquatic ecosystem in the Danube River in Vojvodina

Abstract

The residual concentrations and distribution of polychlorinated biphenyls (PCBs) were studied at different levels of aquatic food web in the Danube River in Vojvodina: in water, sediment, two species of freshwater fish (Cyprinos carpio and Esox lucions), marsh frogs (Rana Ridibunda) and in eggs from three species of aquatic birds (Aythya ferina, Sterna hirundo, N. nycticorax). Environmental samples were collected in 1995 and 2000 in order to determine trends in changes of environmental concentrations of PCBs as a result of NATO intervention in Yugoslavia in 1999. The consequence of uncontrolled spills of transformer oil into the Danube resulted in elevated concentrations of PCBs in amphibians, such as frogs (approximately 35% higher than in pre-bombing period). PCB residues determined in birds' eggs are lower than those commonly associated with mortality and reduced reproductive success.