Importance of microalgae in the biodegradation of tributyltin in estuarine waters

Sampling revealed tributyltin (TBT) concentrations lower than 5 ng/l in an estuarine river along the Georgia coast. Half-lives of TBT added to these waters were in the 3-13 d range. Research suggests that microalgae play an important role in TBT degradation in sunlit coastal waters. TBT degradation rates were high in light compared with dark degradation, and there was no evidence of TBT photolysis. Hydroxybutyltins and dibutyltin were the major degradation products in light and by diatom and dinoalgaellate cultures, while only dibutyltin was observed in the dark. Stimulation of algal growth may be of use in enclosed aquatic areas with organotins, as dense algal cultures apparently rapidly degrade these compounds.