抄録
The environmental impacts of organotin compounds (OTs) and their residues and breakdown products have been of concern since their ecological effects were discovered. Tributyltin (TBT) and triphenyltin (TPT) concentrations in Japanese coastal waters have drastically decreased since 1990, and have remained low in recent years, because domestic use of TBT and TPT has been restricted. OTs, including TBT; TPT; and the breakdown products dibutyltin, monobutyltin; diphenyltin, and monophenyltin, were measured in surface water, bottom water, pore water, and sediments collected from Hiroshima Bay, Japan. TBT concentrations in surface water were lower than those reported in previous Japanese studies. However TBT concentrations in sediments were similar to those reported in previous Japanese studies. This implies that deposited OTs in sediment persist in the environment. OT concentrations in water samples decreased in the order pore water > bottom water > surface water, suggesting secondary contamination caused by OTs in sediments.