Biotransformation, endocrine, and genetic responses of Anguilla anguilla L. to petroleum distillate products and environmentally contaminated waters

The European eel (Anguilla anguilla L,) was exposed to diesel oil water-sol uble fraction (DWSF) and gasoline water-soluble fraction (GWSF), The potent ial of these fractions to induce endocrine disruption, carbohydrate, and xe nobiotic metabolism effects, as well as genotoxic responses, was investigat ed in a timecourse laboratory study (3 h to 6 days), Both water-soluble fra ctions induced time-related increase in liver ethoxyresorufin-O-deethylase (EROD) activity, as well as the appearance of erythrocytic nuclear abnormal ities (ENA) after a 6-day exposure, revealing its genotoxic properties, Ini tially, DWSF exposure revealed an inhibition of the typical stress response s demonstrated by plasma cortisol and lactate decrease. Nevertheless, this effect progressively disappeared, allowing a plasma glucose and lactate inc rease after 6 days of exposure. Fish exposed to GWSF exhibited a liver alan ine transaminase (ALT) activity increase after a short exposure while the l ongest exposure revealed liver damage expressed as an ALT activity decrease . A field caging experiment, carried out in a harbor area (Aveiro Lagoon, P ortugal), and a complementary laboratory experiment were designed to assess the influence of the daily tide dynamic on polyaromatic hydrocarbon water distribution and effects on liver EROD and ALT activities, as well as ENA f requency. Eels exposed to low- and high-tide harbor waters, in the laborato ry, exhibited a similar degree of genotoxicity, whereas clear differences w ere observed as EROD induction. In the field experiment, caged eels did not display significant responses enhancing the relevance of natural environme ntal factors on toxicity mechanisms as well as on the apparent lack of toxi city in harbor waters. (C) 2001 Academic Press.