Congener-specific data on polychlorinated biphenyls in tissues of common porpoise from Puck Bay, Baltic Sea.

Individual congeners of polychlorinated biphenyls (PCBs), including the highly toxic non-ortho coplanar 3,3',4,4'-tetrachlorobiphenyl (IUPAC No. 77), 3,3',4,4',5-pentachlorobiphenyl (IUPAC No. 126), and 3,3',4,4',5,5'-hexachlorobiphenyl (IUPAC No. 169), and their mono- and di-ortho analogs, have been identified and quantified in the blubber, liver, and muscles of three female common porpoise Phocoena phocoena collected from the Puck Bay (inner Gulf of Gdańsk, Poland) in 1989-1990, to elucidate actual concentrations and toxic potential. The total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent for 13 coplanar PCBs in blubber was 1,500 +/- 470 pg/g wet wt. 2,3',4,4',5-Pentachlorobiphenyl (IUPAC No. 118) was the most contributing individual and occupied between 57 and 67% in total toxic equivalent of coplanar PCBs in blubber, while 2,2',4,4',5,5'-hexachlorobiphenyl (IUPAC No. 153), 2,3,3',4,4'-pentachlorobiphenyl (IUPAC No. 105) and 2,2',3,4,4',5'-hexachlorobiphenyl (IUPAC No. 138) comprised between 9.5-14, 7.6-11.5, and 7.2-11.0%, respectively (totally 82-95%), and 2,3,3',4,4',5-hexachlorobiphenyl (IUPAC No. 156) was absent. A potentially most toxic non-ortho PCB members such as 3,3',4,4',5-pentachlorobiphenyl, 3,3',4,4',5,5'-hexachlorobiphenyl and 3,3',4,4'-tetrachlorobiphenyl were only minor contributors, altogether occupying between 1.0 and 14.5% in total TEQ of coplanar PCBs. Concentrations of total PCBs in lipids of the blubber ranged from 26 to 47 micrograms/g and were comparable or lower than reported earlier for common porpoises from the Baltic Sea, North Sea, and North Atlantic by other authors.