The detection of biomarkers of genotoxin exposure in the European flounder(Platichthys flesus) collected from the River Tyne Estuary

The Tyne Estuary (North East England) is known to contain elevated levels o f polycyclic aromatic hydrocarbons (PAH), compared with other less industri alised English waterways. Previous studies suggest that such contamination is responsible for the toxicity detected in invertebrate bioassays conducte d on water and sediment samples collected from the Tyne. Here we present da ta from a biomonitoring study using hepatic DNA adducts (P-32-postlabelling assay) and bile metabolites (synchronous fluorescence spectrometry) to inv estigate genotoxic exposure in flounder (Platichthys flesus) collected from three sites (Scotswood, Newcastle and Redheugh) along the Tyne Estuary. Fl ounder were also collected from a clean reference site, the Aide Estuary. L evels of bile metabolites (mu g kg(-1) wet weight 1-OH pyrene equivalents) were elevated in flounder caught from the Tyne (Scotswood = 22 247 +/- 3408 ; Newcastle = 14 572 +/- 1888; Redheugh = 21 872 +/- 2935) compared with th ose collected from the Aide (632 +/- 56). The levels of DNA adducts (adduct ed nucleotides per 10(8) normal nucleotides) were also elevated in Tyne flo under (Scotswood = 24.6 +/- 3.2; Newcastle = 34.4 +/- 3.7; Redheugh = 27.6 +/- 6.3) compared with fish collected from the Aide (10.1 +/- 4.8), suggest ing that a proportion of the bioavailable PAH was being converted into geno toxic metabolites. All DNA adduct profiles in flounder collected from the T yne consisted of diagonal radioactive zones of radiolabelled adducts, which were not present in fish sampled from the Aide. The in vivo dosing of flou nder with benzo[a]pyrene (BaP) to produced DNA adducts in similar chromatog raphic positions to the diagonal radioactive zones in the Tyne caught floun der are also described. (C) 1999 Elsevier Science B.V. All rights reserved.