Accumulation of butyltin compounds in dolphins stranded along the mediterranean coasts

Concentrations of tributyltin (TBT) and its degradation products, monobutyl tin (MBT) and dibutyltin (DBT), were determined in the liver and kidney of striped dolphins ( Stenella coeruleoanlba), bottlenose dolphins ( Tursiops truncatus) and in a fetus of the common dolphin (Delphinus delphi) found st randed along the western Italian and Creek coasts in the period 1992-1994, Butyltin (BT) compounds were detected in almost all the samples analyzed an d were higher in the kidney than in the liver. Total BT concentrations were 0.78-8.05 mu g g(-1) wet wt in kidney and 0.015-1.02 mu g g(-1) wet in liv er of S. coeruloenlba. Bottlenose dolphins had lower BT concentrations than striped dolphins. Although only one fetal sample was analyzed, it showed t he highest BT concentrations of all. Unlike BT concentrations in the other adult dolphins, in the pregnant dolphin they were higher in the liver (4.35 mu g g-' wet wt), suggesting that BTs are transferred from mother to fetus , No significant differences in BT concentrations were found between sexes. Of the breakdown products, DBT was predominant in most liver samples and M BT was more abundant in kidney. Although BT concentrations are known to be found in cetaceans inhabiting waters of developed countries, our observatio ns strongly suggest that concentrations found in S. coeruleoalba were eithe r similar to or higher than those reported for other Stenella species colle cted from coastal areas close to harbors or marinas. Copyright (C) 2000 Joh n Wiley & Sons, Ltd.