The 1968 Yushō poisoning exposed dangers of PCB contamination in food production, affecting 14,000 people and prompting global reductions in PCB manufacturing use.
Key Facts
- People affected
- Approximately 14,000
- Deaths
- More than 500
- Poultry deaths
- 400,000 birds
- Contaminants
- PCBs and polychlorinated dibenzofurans (PCDFs)
- Source company
- Kanemi Company, Kyushu
- Related Taiwan incident
- Yu-cheng disease, 1979
By the Numbers
Location
Cause → Event → Consequence
In January 1968, the Kanemi Company in Kyushu used PCBs as a heating medium during the deodorization of rice bran oil. Holes in the pipes allowed PCBs to leak directly into the oil, contaminating it with both PCBs and polychlorinated dibenzofurans (PCDFs). The tainted oil was subsequently distributed to poultry farmers as feed supplement and to consumers for cooking.
The contaminated rice bran oil caused mass poisoning across northern Kyushu. About 14,000 people were affected, suffering symptoms including dermal and ocular lesions, lowered immune response, fatigue, headache, cough, and unusual skin sores. Children exhibited poor cognitive development. Some 400,000 poultry birds also died, with farmers first reporting unusual mortality in February and March 1968.
More than 500 people died as a result of the poisoning. The Yushō incident prompted scientific research into PCB and PCDF toxicity, revealing that even low PCB levels could kill fish and wildlife. This contributed to global reductions in the industrial use of PCBs. A nearly identical incident, Yu-cheng disease, occurred in Taiwan in 1979 under comparable circumstances.