Induction of the Hepatic Biotransformation System of Golden Ide (Leuciscus idus (L.)) after Exposure in the River Elbe

The xenobiotic-metabolizing enzyme system of hatchery golden ide [Leuciscus idus (L.)] were tested for applicability in biological monitoring in rivers. The golden ide, cyprinid fish used for toxicity testing, were caged for 1 to 3 weeks in flowthrough systems at various locations of the river Elbe. The activities of 7-ethoxycoumarin-O-deethylase (ECOD) and the cytochrome P450 (P450) concentrations in the livers were analyzed. Exposure in the river Elbe increased the ECOD activity and the P450 concentration. In a flowthrough basin located in the harbor of Hamburg the ECOD activity increased up to 3.5 times, and the P450 concentration increased slightly by a factor of 1.5. During exposure of the golden ide at two Elbe stations upstream and downstream the city of Hamburg, levels of P450 in the livers did not change significantly when compared with laboratory controls. There was, however, a significant increase of ECOD activity between stations Bunthaus (upstream) and Blankenese (downstream). The ECOD activity in the livers of golden ide caged downstream were significantly higher compared to those at the upstream station. The results presented in this study suggest that golden ide can be employed as experimentals for routine measurements in limnic habitats using biochemical assays.