1956 or so, a strange disease appeared near Minamata City, Kumamoto Prefecture, Japan. Sick people have slurred speech, facial dementia, paralysis of hands and feet, and even mental disorders, bending over and screaming until they die.

This strange disease is not just a person, but a large-scale outbreak and spread. Nearly a quarter of the city's population is infected with this strange disease, also known as Minamata disease. Since this incident broke out, its impact is still continuing. Historically, the Minamata disease in Japan has been called one of the eight major public hazards in the world.

At that time, after investigation, it was found that 1925, Japan Nitrogen Fertilizer Company built a factory near Minamata City, Kumamoto Prefecture, Japan, and then built a factory to synthesize acetic acid. Japan Nitrogen Fertilizer Company began to produce vinyl chloride (chemical formula C2H3Cl) from 1949, and the annual output is increasing. By 1956, the output of this plant of Japan Nitrogen Fertilizer Company has reached 6000 tons.

But in the process of synthesizing vinyl chloride and vinyl acetate, mercury is needed as a catalyst. This makes mercury exist in industrial wastewater produced in the production process. However, the factory did not treat these industrial wastewater, and directly discharged these wastewater into the sea.

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History will repeat itself.

Japanese nitrogenous fertilizer company is very passive in dealing with this matter. Instead of stopping discharging industrial wastewater, it tried to cover up the truth and hired thugs to beat photographers. The Japanese government is also very passive in handling this matter. It took 12 years to determine that the factory caused mercury poisoning.

Not only that, the Japanese government has not learned the lesson. Just before the Minamata incident was clarified, a similar incident broke out in another part of Japan, which was called the second Minamata disease in history.

Similarly, the culprit this time, Showa Electric Company, like Japan Nitrogen Fertilizer Company, tried to evade responsibility. As a result, local residents were very angry and filed a lawsuit in court. It took them seven years to finally win the lawsuit.