DNA adducts in perch (Perca fluviatilis) living in coastal water polluted with bleached pulp mill effluents

DNA adducts were analyzed by (32)P-postlabeling in liver and intestine of perch (Perca fluviatilis). Fish were collected in the receiving water of a bleached kraft pulp mill at Norrsundet, Sweden, on the coast of the Bothnian Sea, and in three different reference areas. Sampling was carried out the last week in September 1993, 1995, and 1997. Since 1984/1985 the pulping process at Norrsundet has been successively modified and an external waste-water treatment has been installed, resulting in lowered and altered effluent discharges. Nevertheless, perch captured in the water area closest to the mill (2 km) had significantly elevated levels of aromatic/hydrophobic DNA adducts in both liver and intestine when compared to perch captured 8 km away and in the reference areas. Autoradiograms indicated a diagonal zone consisting of multiple overlapping adducts, a pattern typical of exposure to a complex mixture of aromatic/hydrophobic genotoxic substances. No significant difference in adduct levels was detected between the years. Results from this study reveal that fish in the area closest to the mill are exposed to substances with a genotoxic potential.