Effet de l'uranium sur la reproduction du poisson zèbre, Danio rerio: lien entre biomarqueurs d'exposition et d'effets.

Titre du congrès :SETAC Europe - 18th Annual Meeting
Ville du congrès :Varsovie
Date du congrès :25/05/2008

This work is part of an ongoing PhD study on the effects of radionuclides in Zebrafish, Danio rerio, a widely used freshwater fish for Ecotoxicological standard tests. Our aim is two fold: (i) to identify sensitive life stages and associated endpoints to each life history trait (from ecological parameters to biomarkers) and (ii) to evaluate their relevance for the specie life cycle. A part of this work is devoted to the study of the effects of uranium (U) on the reproductive function of adults. After 20 days of exposure to U concentrations (0, 20, 250 µg/L), the effects on ecologically relevant life history traits (laying, eggs fertilization and survival) were studied in parallel to biomarkers of exposure (ie. U bioaccumulation in the gonads and eggs/larvae) and of effects. As the radionuclides are known to induce DNA damages, we measured genotoxic effects in reproductive organs (comet assay). The effect of U on the structure and maturation of reproductive cells was also assessed through histological analysis. These results will be discussed in order to assess the usefulness of biomarkers at the tissue and/or cell level to predict effects on more relevant ecological endpoints.