EARTH Thailand


Minamata Disease and the Mercury Pollution of the Globe

By Masazumi Harada, 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. 


Minamata Disease: The History and Measures

Environmental Health Department, Ministry of the Environment, 2002

Minamata Disease, which is a typical example of the pollution-related health damage in Japan, was first discovered in 1956, around Minamata Bay in Kumamoto Prefecture, and in 1965, in the Agano River basin in Niigata Prefecture. Since the discovery of the disease, investigation of the cause has been made, and finally in 1968, the government announced its opinion that Minamata Disease was caused by the consumption of fish and shellfish contaminated by methylmercury compound discharged from a chemical plant.


Mercury pollution in the Tapajos River basin, Amazon Mercury level of head hair and health effects

Published by Environment International, 2001

There is increasing concern about the potential neurotoxic effects of exposure to methylmercury for the 6 million people living in the Amazon, even in regions situated far away from the gold mines, considered to be the major source of mercury pollution. In November 1998, a spot investigation on mercury contamination was conducted in three fishing villages on the Tapajos River, an effluent on the Amazon, situated several hundred kilometers downstream from the gold-mining areas.