Baseline Measurements of Butyltin in U.S. Harbors and Estuaries

Water samples collected from fifteen U.S. harbors and adjacent estuaries have been analyzed for butyltin concentrations. Antifouling paints are the principal source of butyltin compounds in these coastal environments. Sampling sites were selected based on specific harbor use criteria (i.e. civilian/commercial, recreational, natural resource or ecologically sensitive areas and military areas). Highest concentrations of tributyltin (TBT) compounds in surface waters (maximum of 0.35 ug TBT/l) were found within marinas, small boat harbors and adjacent to vessel repair facilities. Highest sediment and tissue solvent extractable tin values were present in the vicinity of marinas, small boat harbor areas, commercial docks and repair facilities. Sites in open or well-flushed harbor regions often exhibited no measurable (< 0.005 ug TBT/l) tributyltin in surface waters.