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(89-02) Impact of ERIKA Oil Spill in Brittany Coast: Use of Biomarker Index Scale in Monitoring Strategy. Narbonne, J.F.*,1, Daubeze, M.1, Clerandeau, C.1, Boquene, G.2, Burgeot, T.2, Garrigues, P.1, 1 LPTC, UMR CNRS 5472, University Bordeaux 1, Talence, France2 DEL, IFREMER, Nantes, France ABSTRACT- The ERIKA oil spill occurred in Dec. 1999, oil spread down the southern coast of Brittany. Ten thousand tons of oil (Fuel Nr 2) containing high MW PAHs, methylated and sulfurated PAHs and mixture of heavy metals (vanadium, nickel, aluminium). Mussels was used as sentinel organism for the MONERIKA program (monitoring of the long term impact due to the ERIKA oil spill). The pollution assessment involved chemical measurements and indices of biological effects. The biomarker index scale was used for the first time in France in oil spill monitoring strategy. Mussels were sampled monthly (from Jan. to Dec. 2000) in 14 sites along the southern coast of Brittany. A battery of biochemical parameters were used to evaluate the response of mussels. Acetyl cholinesterase activity (AchE) is inhibited by some pesticides and also by heavy metals. Catalase activity (CAT) and lipid oxidation (evaluated as MDA) are markers of oxidative stress induced by number of organic and inorganic contaminants. Glutathione S transferase activity (GST) is related to conjugation of organic compounds and Benzo(a)pyrene hydroxylase (BPH) is induced by coplanar chemicals. AChE and GST were measured in gills (topic contamination from water column). BPH, GST, CAT and MDA were measured in digestive gland (systemic way from food chain pollution). For each biochemical parameter a response index was allocated taken in account the levels of discrimination (variation range/confidence interval). For each site, a global index was calculated as a sum of index of 5 discriminent biomarkers. Finally a pollution scale was established including five levels (from lightly to highly contaminated). The global biomarker index of each site and for each month was converted in pollution level and associated to a color (red, orange, yellow, green and blue for classes from 5 to 1). These colors were reported on the map of the collected sites in order to visualize easily the temporal changes in effects of pollution. The results showed that for 8 sites the response to pollution were very significant during the 6 first month (from blue or green to yellow). For 4 sites, the index were slightly increased the 6 first month (green) and in 2 clean sites the index was mainly blue). Key words: ERIKA , oil, biomarkers, heavy metals |
