Organotin Concentrations in Centrifuged versus Uncentrifuged Water Column Samples and in Sediment Pore Waters of a Northern Chesapeake Bay Tributary

Butyltin concentrations in centrifuged and uncentrifuged bulk waters were measured over spatial, temporal and tidal distributions. No difference in concentrations were apparent between centrifuged and uncentrifuged samples. These results are consistent with previously reported work suggesting that butyltins are primarily associated with the dissolved fraction of marine waters. Dibutyltin to tributyltin ratios were 2-3 times higher during September then in March. An attempt was made to measure the vertical distribution of butyltins in bulk water, water at the sediment-water interface, and sediment pore waters by simultaneous hydridization/extraction with gas chromatography flame photometric detection. Butyltins were detected in each type of water sample however interferences and poor recoveries made accurate determinations of water at the sediment-water interface and sediment pore waters difficult.