|
(42-10) Biological effect of Benzo[a]pyrene in mussels: Ecotoxicological model for TEF (Toxic Equivalent Factor) determination. Faucet, Jérôme*,1, Mujdzic, Nedzad2, Legris, Audrey1, Maurice, Manuelle1, Rousseau, Sabrina2, Auffret, Michel2, Ménard, Dominique1, Minier, Christophe3, Burgeot, Thierry1, 1 IFREMER centre de Nantes. Rue de l'Ile d'Yeu. BP 21105, Nantes, France2 Institut Universitaire Européen de la Mer.LEMAR., Plouzané, France3 Université du Havre. BP 540, Le Havre, France ABSTRACT- Mussels (Mytilus edulis) were exposed during 14 days to various concentrations of Benzo[a]pyrene (10-2 nM - 103 nM). The time-course study of biomarkers of both PAH exposure and effect was assessed in different tissues (digestive gland, gills and haemolymphe). DNA adducts, single DNA strand breaks and phagocytic activity were respectively measured as biomarkers of genotoxicity and immunotoxicity. The activities of benzo[a]pyrene hydroxylase (BPH), glutathion S-transferase (GST), catalase (CAT) and DT-diaphorase (DTD) were measured in order to evaluate biotransformation, conjugation activities and oxidative stress. Acetylcholine esterase (AChE) activity was measured as an indication of possible neurotoxicity of Benzo[a]pyrene (B[a]P), whereas the induction of the multixenobiotic defense (MXR) mechanism was determined as cellular response to toxical stress. In parallel, primary cell cultures of digestive glands and gills were exposed to the same concentrations of B[a]P and cellular viability was measured by the MTT test. The main topic of this study is to obtain concentration-response curves for B[a]P, the reference PAH compound. Adopting the same approach, the concentration-response will be obtained for other PAHs to define Toxic Equivalency Factor (TEF) for the mussel. The TEF concept developed for this sentinel species will be useful in carrying out predictive screening of environmental exposure. Key words: Mussel, Benzo[a]pyrene , Biomarkers, Toxic Equivalent Factor (TEF) |
