Yusho Disease is a condition caused by poisoning with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs). This primarily refers to a specific mass poisoning with PCBs and PCDFs in rice bran oil, which occurred in northern Kyushu, Japan, in 1968. About 14,000 people who had consumed the contaminated rice oil in Japan were affected. Common symptoms included some abnormalities on the skin and eye tissues, irregular menstrual cycles and a lowered immune system. Other symptoms included fatigue, headache, cough, and unusual skin sores. Additionally, in children, there were reports of poor cognitive development.
An almost identical case occurred in Taiwan a decade later in 1979, known as Yu-cheng disease.