Mitsui Mining formally admitted that itai-itai disease was caused by their discharge of cadmium into the Jinzū River.
[6] The methylmercury inside the contaminated fish attacked the affected patient's central nervous system, which caused a variety of symptoms.
Chisso Corporation produced acetaldehyde using water, acetylene, mercury(II) sulfate as a catalyst and manganese dioxide or since August 1951, ferric sulfide as a co-catalyst.
In 1970, the Japanese Water Pollution Control Act, which states that all factories are required by law to regulate disposal of dangerous chemicals, was enacted.
The degree of this outbreak was minimal[clarification needed] compared to that of the first Minamata disease that took place in Kumamoto prefecture.
After much controversy, Showa Denko was found guilty of negligence and was then forced to pay compensation payments to all those affected by Niigata Minamata disease.
In the year that Niigata Minamata was discovered, 26 people were designated disease patients, and five died as a result of the methylmercury poisoning.
In the middle of this city was the largest heavy oil-fired power station and refinery in Japan during this time period.
This form of asthma was prevalent within Yokkaichi—5–10% of inhabitants aged 40 in Yokkaichi were reported to have chronic bronchitis, whereas less than 3% had the same disease in non-polluted areas.
[12] To offer support for many of the people affected by disease, a public release system for air pollution was established in 1965.
This set forth that all people in the Yokkaichi area who met the following criteria were paid by the program: Today, there are many laws regulating the amount of sulfur dioxide a factory can release into the air.