Assessing pollution in the Danube River near Novi Sad (Serbia) using several biomarkers in sterlet (Acipenser ruthenus L.).

The response of wild fish to pollutants was studied in sterlet (Acipenser ruthenus L.) collected in 2001 and 2002 at two sampling sites in the Danube River near Novi Sad (Serbia): in the vicinity of the oil refinery and at the Danube-Begec, remote from the oil refinery and considered a reference site. The following biomarkers were measured in sterlet collected from these two sites: the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px), and glutathione S-transferase and the induction of CYP1A1 in liver and the activities of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase in serum. The results demonstrated increase in the activity of SOD and GSH-Px in sterlet collected from the Danube-oil refinery (DOR) compared to that from the reference site, while no differences were found in other enzymes. In conclusion, the overall results suggest that an alteration in the activity of SOD and GSH-Px during the observed period reflects the presence of certain prooxidative compounds that can lead to oxidative stress in the liver of sterlet at the DOR site.