Inputs and distribution of the PCBs [polychlorinated biphenyls] in the southern bay of the North Sea: an attempt of synthesis
1994
Thome, J.P. | Louvet, M. | Hugla, J.L. (Liege Univ. (Belgium). Inst. de Zoologie. Service d'Ecologie Animale. Lab. d'Ecotoxicologie)
The input flows of PCBs in the southern bay of the North Sea were determined according to the contamination values measured in rivers whose estuaries are located in Belgian and Dutch coasts (the Meuse, Rhine and Scheldt) and on the English coast. As the transfer of PCBs through the air water interface is a significant process which affects their transport and distribution in the environment, the output atmospheric PCB flow from rivers and North Sea has been approached by means of a vaporisation model. In spite of the high levels of PCB contamination in the living organisms (plankton, fish) of the rivers Meuse, Scheldt and Rhine and of the North Sea, the PCBs appear mainly located in suspended matter and in sediments. The total incoming flow of PCBs in the North Sea is estimated at 9300 kg PCBs per year. Levels of sedimentation of suspended matter were taken into account when determining this net input flow. Depending on variations in temperature and PCB concentrations dissolved in the water, the output flow by vaporisation and co-distillation processes is estimated at between 4000 and 8000 kg PCBs per year. As a consequence this atmospheric fate of PCBs to other ecosystems limits the build-up of PCBs in the southern bay of the North Sea.
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