Temporal trends of organotin compounds in the aquatic environment of the Port of Osaka, Japan

Between 1989–1996, butyltin (Bt) and phenyltin (Pt) compounds were monitored in water, sediment, plankton and mussels from the Port of Osaka. Tributyltin (TBT) compounds concentration in water and mussels decreased remarkably in a marina and the mooring places in a zone of poor flushing during 1989–1996. With regard to the composition of Bts in water, the dominant compounds changed from TBT to monobutyltin (MBT). The ratio of TBT in mussels was high throughout the study period. Drastic changes of TBT concentrations in sediment and plankton were not observed. High levels of triphenyltin (TPT) were detected in water between 1989 and 1991, but TPT have not been detected since 1992. Detection frequencies of TPT in sediment and plankton were also very low. TPT levels in mussels were high in 1989 but decreased dramatically thereafter.