Mercury, DDT, and PCB in Harbour Seals (Phoca vitulina) from the Bay of Fundy and Gulf of Maine

Abstract

Samples of blubber, longissimus muscle, liver, and cerebrum from 12 harbour seals (Phoca vitulina) were analyzed for DDT, dieldrin, PCBs, and total mercury content. The results were compared with those obtained previously for harbour porpoises (Phocoena phocoena). DDT and PCB levels appear to be of the same magnitude in the fat of seals from both southern New Brunswick and southern Maine, being lowest in a lactating female. Virtually no o,p′-DDT and relatively little dieldrin were found in seal fat, in contrast to porpoises, which contained significant amounts of both in the depot fat. Mercury levels were generally similar to those found for porpoises, but total liver Hg was considerably greater in adults from the New Brunswick islands than in those from the southern Maine ledges.