MEPS 122:307-312 (1995)  -  doi:10.3354/meps122307

Previous studies have indicated that hydrocarbon induction of the hepatic microsomal monooxygenase Cytochrome P450 1A (CYP1A) is attentuated in certain species of fish by low temperature and in sexually mature female fish by estradiol. This enzyme is used as a biomarker for petroleum hydrocarbon exposure, and with impending oil exploration of the Arctic, in particular the Barents Sea, the current studies were carried out to establish the nature of the response of hepatic CYP1A to dietary petroleum hydrocarbon injestion in Polar cod at their natural environmental temperatures during the breeding season. Polar cod Boreogadus saida maintained at 0*C contain a hepatic CYP1A which displays immunochemical and nucleotide homology with other piscine CYP1As and displays typical transcriptional induction by ß-napthoflavone or crude mineral oil. The enzyme is induced in both male and female fish fed artificial diets contaminated by crude oil during the period of sexual maturation despite an overall suppression of activity in female fish and a cessation of feeding for 3 wk immediately prior to spawning. The results indicate that use of CYP1A measurements in this species for biomonitoring oil exploration and production in the Arctic environment is a valid procedure.

Polar cod · Crude oil · Diet · Induction · CYP1A · Environmental monitoring