Occurrence and bioaccumulation of organochlorine compounds in fishes from Siskiwit Lake, Isle Royale, Lake Superior

Abstract

A wide range of chlorinated organic compounds was measured in different size classes of lake trout (Salvelinus namaycush namaycush) and whitefish (Coregonus culpeaformis neohantoniensus) from Siskiwit Lake, a remote lake on Isle Royale in Lake Superior. Our results confirm the long-range transport of several chlorinated pesticides and polychlorinated biphenyls (PCBs) and, in addition, indicate that technical chlordane constituents, octachlorostyrene, pentachloroanisole, and decachlorodiphenyl ether also are transported to remote locations. Chemical concentrations as a function of fish age (size) were not similar between species and were not consistent among compounds. Differences in bioaccumulation with age between species for a given compound indicated that physical-chemical properties alone do not determine bioaccumulation in a species; fish characteristics are also important. The relationship of the bioconcentration factor (BCF) and the octanol-water partition coefficient (K{sub OW}) was examined. The correlation was weak for pesticides and poor for PCB congeners when compared to published relationships based on laboratory data.