[Contamination of Baltic Sea fish with polychlorinated biphenyls].

Using a reaction gas chromatographic method, the authors determined the PCB contents of important fish species from three major fishing-grounds in the Baltic sea. They found that the PCB contents had but insignificantly changed in the period 1975--1979. Due to the simultaneous considerable reduction in total DDT content, there is a drift in the PCB/total DDT ratio. The causes of regional and seasonal variations are discussed.