Residues of Organochlorine Pesticides and Polychlorinated Biphenyls in Some Commercially Produced Canadian Marine Oils

Abstract
Herring oils produced in the late 1960s from Gulf of St. Lawrence fish generally contained 7–17 ppm DDT complex, 0.1 ppm dieldrin, and up to 11 ppm PCBs. In spring, oils were richer in residues than in autumn. Seal oils contained up to 8 ppm DDT complex, and about 4 ppm PCBs, but no dieldrin. Residue levels showed no marked change from the mid-1950s to mid-1960s. North Atlantic whale oils contained up to 40 ppm DDT complex, and (in a few samples only) about 7 ppm PCBs; no dieldrin was found. Some Antarctic whale oils produced about 1950 contained 0.1 ppm DDT complex and no detectable PCBs.