Minamata Disease and the Mercury Pollution of the Globe
By Masazumi Harada, M.D., Ph.D., Department of Social Welfare Studies, Kumamoto Gakuen University, March 2003
Minamata Disease was discovered for the first time in the world at Minamata City, Kumamoto Prefecture, Japan, in 1956, and for the next time at Niigata City, Niigata Prefecture, Japan, in 1965. The both cases were attributed to the methyl mercury that was generated in the process for producing acetaldehyde using mercury as catalyst. Methyl mercury had accumulated in fishes and shellfishes and those who ate them had been poisoned with it. These cases of the poisoning with organic mercury poisoning were the first to take place in the world through the food chain transfer of its environmental pollution. The cases of organic mercury poisoning that had been known prior to Minamata Disease occurred as the result of the direct poisoning of those who were engaged in organic-mercury handling occupations or those who took it in accidentally.