Induction of hepatic aryl hydrocarbon hydroxylase in salmon exposed to petroleum dissolved in seawater and to petroleum and polychlorinated biphenyls, separate and together, in food

Abstract

1. Hepatic AHH is induced in coho salmon exposed to 1 ppm PCB's in the diet; however, comparable experiments with 1 ppm of Prudhoe Bay crude oil did not significantly alter the AHH activities. These findings suggest that in aquatic food-chains containing both petroleum hydrocarbons and PCB's, the latter compounds may exert a predominant influence on the induction of the hepatic AHH enzyme system. 2. Despite the lack of induction of hepatic AHH with 1 ppm Prudhoe Bay crude oil in the diet, young coho salmon exposed to 150 ppb (0.15 ppm) of a seawater-soluble fraction for 6 days exhibited a significant induction of this enzyme system. Thus, crude oil components of relatively high water solubility (e.g., methylated naphthalenes and polyalkylated benzenes) may be more effective than high molecular weight insoluble components in inducing AHH.