UMR CNRS 5805 EPOC
Environnements et Paléoenvironnements
Océaniques et Continentaux

        

Consignes de Sécurité et Numéros d'Urgence
(à l'usage des personnels du laboratoire)

le 05-06-2018 à 10:30

Lieu Salle Univers, Bâtiment B18N, OASU, Université de Bordeaux Intervenant(s) Maikel Rosabal, Université de Québec à Montréal

Mining, and smelting-related activities represent an important economic sector for many countries and they are expected to increase in the next years. In this context, there is an urgent need to provide science-based regulatory tools to environmental risk assessors (ERA) to better predict the toxicity of trace elements. Current ERA models have not been completely successful in relating bioaccumulation to toxicity of trace elements. Metallomic studies including subcellular metal partitioning analyses and hyphenated techniques have been shown to provide significant insights into metal toxicity in living cells. Knowledge of subcellular partitioning of trace metals in the cells of aquatic organisms is useful for understanding and predicting metal toxicity. Such approach allows one to distinguish metal accumulation in detoxified metal fractions, which do not represent a toxicological risk, from metal binding to physiologically sensitive target molecules (e.g., cytosolic enzymes, receptors, carriers) and organelles (e.g., mitochondria), where the inappropriate binding of non-essential elements can induce deleterious effects. In addition, detailed characterizations of the biomolecules either involved in metal-detoxification responses or those harmfully targeted by the trace metals are also required. Biochemical information on both constituents of these metal-biomolecule complexes is necessary to understand how non-essential elements elicit their toxicity. To address this last point, multidimensional analytical strategies has been recently applied with the development of hyphenated techniques that combine a high-resolution separation technique with sensitive elemental or molecular MS detection. Here, I will share our recent metallomic studies on several animals with differing tolerance to trace elements collected from metal-contaminated environments. Such information should help the development of improved models for predicting metal toxicity, based on the biologically active pools that contribute to toxic responses and not on the total accumulated metal concentrations.