On the possibility to produce again oysters Crassostrea gigas in the North Médoc salt marshes (Gironde estuary, Southwestern France): A comparison study of metals bioaccumulation in spats 13years after.

The Gironde Estuary is known for its historic poly-metallic contamination, leading to levels of Cd in oysters Crassostrea gigas above the human consumption limit. However, since 25years, Cd concentrations progressively decreased in the estuary and the question is raised if the same evolution occurred in the North Médoc salt marshes. In this aim, we analyzed 12 metals in juveniles of oysters transplanted from a hatchery on a 12months period in 2 salt marshes.