DISTRIBUTION OF ORGANOCHLORINE POLLUTANTS IN NORTH-SEA SEDIMENTS

Sediment samples from the North Sea and the Skagerrak were analyzed for organochlorine pollutants. Standardisation for organic carbon content of sediments proved to be a suitable tool for comparison of pollution of different sea regions. Relatively high contaminant concentrations were found in coastal regions of the southern North Sea, while standardised organochlorine concentrations in the Skagerrak were almost at baseline level. In addition to the major inputs via rivers and the atmosphere, ocean incineration of hazardous wastes was identified as a probable source of organohalogen pollution. Although the production and use of certain organochlorines have been restricted in most North Sea states, depth profiles from the Skagerrak indicate that deposition of these contaminants has increased until recently. This trend will possibly continue since only a very small proportion of all persistent organochlorines produced in Western Europe in the past has already reached the sea. As a consequence, no persistent and bioaccumulable organics, like most organohalogens, should be allowed to enter the sea in the future. This, in many cases, will necessitate not only better filter techniques, but a dramatic reduction of organic chemical production itself.