POLYCHLORINATED BIPHENYL CONCENTRATIONS IN COD-LIVER OIL - EVIDENCE OF A STEADY-STATE CONDITION OF THESE COMPOUNDS IN THE BALTIC AREA OILS AND LEVELS NOTED IN ATLANTIC OILS

A steady-state condition of polychlorinated biphenyl (PCB) pollution i s evident in cod-liver oil samples of fish collected from the Baltic a rea between 1971 and 1989. Spatial differences in the concentration of congeners and isomers of these chemicals between the Baltic Sea and o ther areas in the north and northeastern part of the Atlantic Ocean ap peared to be rather small. A site relatively distant from the PCB sour ces of the European continent, an open ocean environment near Iceland, showed a fivefold lower concentration of many PCB congeners than the Baltic Sea. The open and deep waters of the North Sea and Norwegian Se a differed by a factor of 2 in the total concentrations of PCBs when c ompared with the southern Baltic proper. Continuous release of PCBs in to the atmosphere over Europe, its drift from distant sources in North America, and further aerial transport and deposition due to dominatin g air masses movement from the west and southwest are postulated to be the main routes of PCBs pollution and a reason for the small differen ces in concentration between the marine areas assessed.