Freshwater fish cytochrome P450-dependent enzymatic activities: a chemical pollution indicator

Fish mixed function oxidase activities were measured during four sampling campaigns in the river Durance in the southeast of France. Six hundred fish belonging to four species were caught for this study; the use of factorial analysis emphasizes the strong pollution dependence of the P450-dependent enzymatic activities which vary with the season, the species, and the sex of the fish. Regression analysis of the data allowed prediction of the type of location from which the fish came (polluted or unpolluted) for 80% of the fish. This supports use of such activities as chemical pollution indicators.