Chlorinated microcontaminants in surface sediments of the Baltic Sea—Investigations in the Belt Sea, the Arkona Sea and the Pomeranian Bight

Sediment samples were taken in October/November 1993 in the southern and western Baltic Sea and analysed for chlorobiphenyls (CBs), including non-ortho substituted congeners, and organochlorine pesticides. The concentrations of individual chlorobiphenyls ranged between <10 to 2600 pg g−1. For DDTs values were found from <10 pg g−1 in sandy sediment to 9000 pg g−1 in muddy samples. Concentrations of HCH isomers and HCB were often below the detection limit up to 370 pg g−1. Values depend on sources (shipbuilding industry, shipping and agriculture) and physicochemical properties of organochlorines as well as the sediment structure. Generally, higher concentrations oere detected in the sedimentation areas of Lübeck Bight and the Arkona Basin. However, higher values were also found in the nearshore areas of the Pomeranian Bight due to local discharges of the river Oder. The total carbon normalization of the data showed that also resuspension followed by transport processes takes place to the accumulation areas of the investigated area over long distances.