Mercury methylation by a microbial community from sediments of the Adour Estuary (Bay of Biscay, France)

Robert Duran (1) , Magali Ranchou-Peyruse (1) , V. Menuet (1) , Mathilde Monperrus (1) , Gilles Bareille (1) , Marisol Goñi (1) , J.C. Salvado (1) , David Amouroux (1) , Remy Guyoneaud (1) , Olivier François Xavier Donard (1) , Pierre Caumette (1)

1 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

In order to study the influence of microorganisms on the mercury biogeochemistry, the metal content and the structure of microbial communities were determined in sediments from stations along the Adour Estuary. The comparison of the bacterial communities and their distribution in function of the environmental parameters by Canonical Correspondence Analysis (CCA) revealed the influence of metals on the bacterial communities structure. Sediments where the bacterial communities are mostly influenced by methylmercury were incubated in slurries with or without mercury, under oxic and anoxic conditions. Methylmercury production was detected in the anoxic biotic slurries with a net methylation yield of 0.3% after 24 h. CCA based on T-RFLP profiles revealed the impact of mercury addition on the bacterial communities structure. In addition, 17 bacterial strains, mainly sulphate-reducing bacteria involved in mercury methylation, were isolated and identified.

Domaines: Géochimie

Robert Duran, Magali Ranchou-Peyruse, V. Menuet, Mathilde Monperrus, Gilles Bareille, et al.. Mercury methylation by a microbial community from sediments of the Adour Estuary (Bay of Biscay, France). Environmental Pollution, 2008, 156 (3), pp.951-958. ⟨10.1016/j.envpol.2008.05.007⟩. ⟨hal-01557339⟩