Dicentrarchus labrax biotransformation and genotoxicity responses after exposure to a secondary treated industrial/urban effluent.
The present research work was designed to study Dicentrarchus labrax (sea bass) biotransformation and genotoxicity responses to the soluble fraction of a secondary treated industrial/urban effluent (SF-STIUE) discharged through a submarine pipe outlet into the Aveiro coastal area. Sea bass was exposed for 4, 8, 16, 24, 48, and 96 h to 0%, 0.1%, and 1% SF-STIUE and the following biological responses were measured: (1) liver cytochrome P450 (P450) content and ethoxyresorufin-O-deethylase (EROD) activity, as phase I biotransformation parameters; (2) liver gluthathione S-transferase (GST) activity as a phase II conjugation enzyme; (3) biliary and liver cytosol naphthalene (Naph)- and benzo(a)pyrene (B(a)P)-type metabolites, by fixed wavelength fluorescence detection (FF); (4) liver DNA strand breaks, erythrocytic micronuclei (EMN), and erythrocytic nuclear abnormalities (ENA) as genotoxicity parameters. Both SF-STIUE dilutions (0.1% and 1%) failed to significantly increase liver EROD activity, despite a significant increase of liver P450 at 16 and 48 h exposure to 0.1%. Liver GST activity increased significantly at 4h of sea bass exposure to 1% SF-STIUE, being inhibited at 96 h of exposure to this SF-STIUE dilution. Naph- and B(a)P-type metabolite contents were not significantly increased in bile. However, Naph-type metabolite contents increased significantly in liver cytosol at 4h exposure to 1% SF-STIUE, and at 24h exposure to 0.1% and 1% SF-STIUE. Furthermore, B(a)P-type metabolites increased significantly in liver cytosol at 4h exposure to 1% SF-STIUE, and 16 h exposure to 0.1% and 1% SF-STIUE. EMN and ENA frequencies increased significantly at 4, 8, 16, 24, 48, and 96 h exposure to 0.1% and 1% SF-STIUE. Liver DNA integrity decreased significantly at 96 h of sea bass exposure to 1% SF-STIUE. The STIUE discharged into Aveiro coastal area is of great ecotoxicological concern due to its genotoxic potential.
Gravato
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Department of Biology, Animal Physiology/Ecotoxicology Sector, University of Aveiro, Aveiro 3810-193, Portugal. gravatoc@bio.au.pt
Santos
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MA
D000818:Animals; D001492:Bass / Q000502:physiology*; D001711:Biotransformation; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis / Q000494:pharmacology; D004249:DNA Damage; D005982:Glutathione Transferase; D007220:Industrial Waste / Q000009:adverse effects*; D009152:Mutagenicity Tests; D011084:Polycyclic Aromatic Hydrocarbons / Q000009:adverse effects / Q000378:metabolism; D014018:Tissue Distribution; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000378:metabolism*
D007220:Industrial Waste; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D003577:Cytochrome P-450 Enzyme System; D019363:Cytochrome P-450 CYP1A1; D005982:Glutathione Transferase