Four Big Pollution Diseases of Japan

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.

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.

Itai-itai disease first occurred in 1912 within Toyama Prefecture. This disease was given the name "itai-itai" because this was the phrase victims would frequently cry out; it translates into "it-hurts it-hurts disease".

The cause of itai-itai disease was determined to be cadmium poisoning in the drinking water from the Jinzugawa River basin. The source of cadmium was discovered to be from Mitsui Mining and Smelting Company. Mitsui Mining began to discharge cadmium into the Jinzugawa river in 1910. The cadmium poisoned the river, thus poisoning locals' source of water. Any person who drank that water or ate food that was grown with the contaminated water, such as rice, would be likely to show signs of itai-itai disease.

The first symptoms were spine and leg pain. However, as the disease progresses symptoms include:

Most victims of itai-itai disease were confined to bed because walking caused severe pain. Residents of the surrounding area that were harmed by this disease filed a lawsuit against Mitsui Mining & Smelting Company in 1968. Residents won this lawsuit and began to conduct negotiations. Mitsui Mining formally admitted that itai-itai disease was caused by their discharge of cadmium into the Jinzugawa River. Mitsui Mining was also obligated to pay for recovery costs for the land. This meant that they had to ensure that the land that was poisoned was returned to a safe and cultivable area.

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