The Four Big Pollution Diseases of Japan (四大公害病 yondai kōgai-byō) were a group of man-made diseases all caused by environmental pollution due to improper handling of industrial wastes by Japanese corporations. The first occurred in 1912, and the other three occurred in the 1950s and 1960s.
|Name of disease.||Japanese prefecture affected.||Cause.||Source.||Year.|
|Itai-itai disease||Toyama Prefecture||Cadmium poisoning||Mitsui Mining & Smelting Company||1912|
|Minamata disease||Kumamoto Prefecture||Methylmercury||Chisso Corporation||1956|
|Niigata Minamata Disease||Niigata Prefecture||Methylmercury||Showa Denko||1965|
|Yokkaichi Asthma||Mie Prefecture||Sulfur dioxide||Air pollution within Yokkaichi||1961|
Due to lawsuits, publicity, and other actions against the corporations responsible for the pollution, as well as the creation of the Environmental Agency in 1971, increased public awareness, and changes in industrial practices, the incidence of these kinds of diseases declined after the 1970s.