Study of polluted oysters from Arcachon Bay by chemical and biomolecular speciation methods: organotin compounds

Abstract

The use of a spike of 117TBT as a tracer has assisted in the investigation of butyltin contamination in oysters (C. Gigas). The analysis of incubated oyster organ tissues by gas chromatography-ICP MS has revealed the organotin cytosolic and non-cytosolic distribution and they have been related to the results of the elucidation of contamination pathways of oyster organ tissues. Furthermore, bioconcentration and degradation in the oyster has been studied revealing a high bioconcentration for TBT and DBT, and moderate bioconcentration for MBT whereas the contribution of degradation processes is very low. The analysis of the water-soluble fraction by size exclusion chromatography-ICP MS revealed the metabolization of a minor part of butyltin compounds through the association of Sn species with biomolecules in a molecular weight range between 3·103 and 6·105 Da, biomolecules which sheltered affinity for other metals (Se, Hg, Cd, Cu and Zn).