W.M. Jarman, R.J. Norstrom, D.C.G. Muir, B. Rosenberg, M. Simon, and R.W. Baird
Marine Pollution Bulletin 32:426-436. 1996.
Abstract: Levels of organochlorine compounds (PCDD, PCDF, PCB and organochlorine pesticides) were determined in cetceans collected from the west coast of North America between 1986 and 1989. The samples included gray whale (Eschrichtius robustus), killer whale (Orcinus orca), false killer whale (Pseudorca crassidens), Risso's dolphin (Grampus griseus) and Dall's porpoise (Phocoenoides dalli) collected in British Columbia, and harbour porpoises (Phocoena phocoena) collected in British Columbia and central California. TCDD and TCDF levels ranged from 1 to 8 nm per kg and 2.0 to 209 ng per kg, respectively. The highest levels of PCDDs were found in the harbour porpoises; the levels of 1,2,3,6,7,8-HxCDD in the samples from Victoria, Campbell River and Qualicum River were 128, 128 and 62 ng per kg, respectively. Five other 2,3,7,8-substituted dioxins and dibenzofurans were detected in the cetaceans at levels ranging from 1 to 10 ng per kg. In addition to the 2,3,7,8-substituted congeners, several non 2,3,7,8-substituted congeners were detected. The patterns of the PCDDs and PCDFs in the British Columbia porpoises were consistent with implication of chlorophenols as the source of the PCDDs and PCDFs, which were either present in wood chips used in bleached kraft paper mills, or came from direct contamination by chlorophenols. No PCDDs or PCDFs were detected in the California samples. One false killer whale sample had exceptionally high levels of DDT compounds (1700 mg per kg DDE, 120 mg per kg DDT and 40 mg per kg o,p'-DDT) and toxaphene (89 mg per kg). PCB levels in the cetaceans were highest in the false and killer whales (22 to 46 mg per kg GM), and lowest in the Risso's dolphin (1.7 mg per kg). Levels of DDE in the British Columbia harbour porpoises were 6.0 mg per kg, and probably reflect the accumulation of global background levels of DDE.