Occurrence of methylated tin and dimethyl mercury compounds in a mangrove core from Sepetiba Bay, Brazil

P. Quevauviller , Olivier François Xavier Donard (1) , J.C. Wasserman , F.M. Martin , J. Schneider

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

Analyses of organotin and organic mercury compounds have been performed in a sediment core from Sepetiba Bay, Brazil, in order to investigate possible methylation pathways in a mangrove environment. The results have revealed that the physico‐chemical conditions existing in this type of environment (high organic inputs, anaerobic conditions, microbial activity, etc.) account for high methyltin concentrations (mono‐, di‐ and trimethyltin) in the sediments, which are dependent upon the total load of metal released (e.g. from anthropogenic sources). Furthermore, the presence of dimethylmercury and not monomethylmercury in the samples demonstrated a new pathway of transformation of mercury in the environment: this compound, thought to be unstable in sediment, is assumed to be stabilized by a conjunction of factors, such as high sulphide levels, anoxic conditions and constant inputs of methane into the medium. Copyright © 1992 John Wiley & Sons Ltd.

Domaines: Chimie analytique

P. Quevauviller, Olivier François Xavier Donard, J.C. Wasserman, F.M. Martin, J. Schneider. Occurrence of methylated tin and dimethyl mercury compounds in a mangrove core from Sepetiba Bay, Brazil. Applied Organometallic Chemistry, 1992, 6 (2), pp.221-228. ⟨10.1002/aoc.590060217⟩. ⟨hal-01590155⟩