Past and current medical states of yusho patients.

A subacute poisoning, "yusho," caused by the ingestion of Kanemi rice oil which had been accidentally contaminated with polychlorinated biphenyls (PCBs), occurred in the western part of Japan in 1968. During the past decade, various clinical symptoms of yusho patients have diminished gradually. However, some of the symptoms and signs, such as pigmentation of the skin, conjunctiva and gingiva, eye discharge, and various nonspecific general symptoms still remain in a number of severely ill patients. In this report, clinical observations of yusho patients during 1968-78 are briefly reviewed.