9224717 Weber This is an award the objective of which is to understand the mechanisms for methylation of inorganic tin and dimethylation of methyltin compounds in estuarine salt marshes. This knowledge has potential applicability in determination of the potential hazards that aquatic sediments contained with these compounds pose to aquatic organisms and to their ecosystem. Specifically, the research addresses the seasonal variations of inorganic tin and methyltin compounds in marsh grass, the methylation of these tin compounds in marsh sediments, in sediment slurries and in mixed and pure cultures of microorganisms isolated from the estuarine marsh habitat. Methyl and butyltin compounds are ubiquitous in marine coastal environments, thought generally to have originated from use of tin compounds as ingredients of marine antifouling paints. These compounds wear off or flake from the surfaces to which they are applied and become associated with benthic deposits. Methylated tin compounds are considerably more toxic to life-forms than tin itself, and are more mobile and easily bioaccumulated. Results of this research are expected to provide insights into appropriate management of contaminated aquatic sediments to reduce their potential biocidal effects on the ecosystem into which they are introduced or to which they may be transported.
