Organochlorine levels in North Atlantic right whale (Eubalaena glacialis) blubber

Polychlorinated biphenyls (PCBs), total DDT (DDT + DDE + DDD), dieldrin, heptachlor epoxide, chlordanes, and hexachlorobenzene (HCB) were found in blubber biopsies from endangered North Atlantic right whales (Eubalaena glacialis) in the Bay of Fundy and on Browns-Baccaro Banks. Analyses included four sex and age class composite samples from 1988, and 21 individual samples from 1989. Generally, PCBs demonstrated the highest wet weight residue levels (up to 1.9 micrograms/g), followed by total DDT (DDT + DDE + DDD) (trace to 0.47 micrograms/g). Relatively low residue levels in adult females suggest that transmammary organochlorine (OC) residue transfer occurs during lactation. The actual blubber residue loads may have been underestimated, because the samples were taken when the whales were depositing fat reserves and the samples may not have been representative of the remainder of the blubber.