Distribution of Antifouling Biocides in Sediment Samples

The authors have investigated the distribution of organotin and its alternatives in sediment in various parts of Japan. The concentration of organotin compounds extracted from samples was the highest in Tanabe Bay, followed by Osaka Port, Otsuchi Bay and Maizuru Bay. Especially, Tanabe Bay had a high concentration of triphenyltin. Concerning the alternative biocides, Diuron concentrations were higher at international trading ports and higher concentrations of Irgarol 1051 were observed at fishing ports. Furthermore, the concentrations of tributyltin (TBT), TPT and Irgarol 1051 were high near pollution sources, whereas Diuron was distributed widely away from pollution sources and Sea Nine 211 was detected less frequently. In Southeast Asia, the distribution of antifouling biocides was similar to that of the coastal areas in Japan. Organotin compounds and their alternative biocides were also detected in deep sea sediment.