PHENYLTINS IN WATER, SEDIMENT, AND BIOTA OF FRESH-WATER MARINAS

A series of phenyltins and butyltins were determined in the water column, sediment, and biota of two freshwater marinas of Lake Lucerne, Switzerland. Considerable concentrations of triphenyltin (TPT), diphenyltin (DPT), and monophenyltin (MPT) were found for the first time in all the compartments. In addition, tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) occurred in significant concentrations. During 1988-1990, aqueous TBT concentrations followed a seasonal pattern with increases of up to 752 ng/L in late spring, followed by a successive decrease until winter, when concentrations remainded around 100 ng/L. TPT and TBT concentrations decreased during the observation period. Of the total aqueous TBT, 95-99% was present in the dissolved phase. In mussels Dreissena, TPT and TBT residues ranged up to 3.88 and 9.35-mu-g/g, respectively. Vertical sediment core profiles showed highest TPT and TBT concentrations of up to 107 and 2043-mu-g/kg, respectively, in the top with decreasing values with depth. Dating of the core and the occurrence of only low concentrations of DBT and MBT indicate that TBT is conserved in these sediments over a time period of years.