PCB Contamination - Seas around Japan - May 1998

PCB Contamination - Seas around Japan - May 1998

In 1998, high concentrations of polychlorinated biphenyls (PCBs) and DDT were detected in marine organisms in the waters around Japan as a result of a survey conducted by Ehime University. In particular, 400 micrograms of PCBs per gram of fat were detected in killer whales and dolphins sampled off the coast of Hokkaido and in the East China Sea. PCBs were widely used by companies such as Mitsui Chemicals and Showa Denko during the 1960s and 1970s, but were banned in 1972. However, improper disposal and illegal dumping have continued, and marine pollution around industrial areas such as Tokyo Bay and the Seto Inland Sea has become increasingly serious. PCBs are extremely difficult to decompose and concentrate in the bodies of living organisms, causing serious effects on marine ecosystems and humans. In particular, carcinogenicity and neurotoxicity have been confirmed, and there is concern about the risk to pregnant women and children. The government aims to completely dispose
of PCB waste by 2030, but at present about 20% of PCB waste remains untreated.