Congener-specific profile and toxicity assessment of PCBs in green turtles žChelonia mydas/ from the Hawaiian Islands

Chemical pollution may play a role in the etiology of fibropapillomatosis in green turtles ŽChelonia mydas.. In this preliminary study, polychlorinated biphenyls ŽPCBs. were measured in the livers and adipose fats of green turtles collected after they were stranded on Oahu Island, Hawaii in 1992 1993. Average concentrations of total PCBs were 45 58 ng g dry weight and 73 665 ng g in the liver and adipose tissues, respectively. Hexachlorobiphenyls were predominant homologues, PCBs 153 and 138 were dominant congeners in all the turtle tissues. Among the most toxic coplanar congeners, in the order of abundance, were PCB 77 126 169. Estimated toxic equivalents ŽTEQs. of PCBs to 2,3,7,8-tetrachlorodibenzo-p-dioxin were 8 15 pg g in the livers and 13 48 pg g in the adipose tissues. PCB 126 contributed 85 91% of the total TEQs.