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Minamata Disease Facts

Minamata Disease Facts
Minamata disease is a form of severe mercury poisoning that results in a neurological syndrome. It is also referred to as Chisso-Minamata disease. It was first discovered in 1956 in Minamata in Japan's Kumamoto prefecture. The release of methylmercury into the wastewater released by Chisso Corporation accumulated in the seafood in Minamata Bay. Humans and animals consumed the seafood and mercury poisoning became a serious issue. This continued for 36 years and resulted in the deaths of many people and animals. By 2001 there had been 2,265 official cases of Minamata disease and 1,784 of the victims had died as a result. In 2004 Chisso Corporation had paid $86 million to victims and families and was forced to begin cleanup efforts.
Interesting Minamata Disease Facts:
Chisso Corporation opened a chemical factory in 1908 to produce fertilizer but expanded to produce octanol, vinyl chloride, acetylene and acetaldehyde as well as several other chemicals.
The Chisso Corporation factory in Minamata was Japan's most advanced factory around the time of World War II.
As chemicals are produced waste is also produced. The waste was discharged in factory waste water into Minamata Bay.
In 1926 and in 1943 Chisso Corporation was forced to pay compensation to fisheries in the area due to reduced catches and the effect it had on incomes and the economy.
Mercury sulfate was used in the process to manufacture acetaldehyde, which led to the production of a compound called methylmercury. The methylmercury was subsequently released into Minamata Bay.
Methlymercury was released into Minamata Bay between 1951 and 1968.
Minamata disease was discovered in 1956 when a five year old girl presented to Chisso Corporation's factory hospital. Her symptoms included conculsions, difficulty walking, and difficulty speaking. Additional members of her family began to have the same symptoms a few days later. Health officials investigated and classified the health issue as an 'epidemic of unknown disease of the central nervous system'.
As the investigation into the disease continued it was discovered that animals were also experiencing similar symptoms. Cats with the disease were labeled as having 'cat dance disease'.
Of the first 40 people to be discovered with the mysterious disease 14 died.
The victims of the mysterious disease all had seafood consumption in common. Further research revealed it was from a heavy metal in the seafood.
As the company began to investigate it discovered that heavy metals were present in the wastewater, including arsenic, manganese, lead, copper, manganese, and others. In 1959 it was finally discovered that mercury was the culprit.
Chisso Corporation, knowing it was suspected of the contamination, diverted the wastewater to the Minamata River and the mercury poisoning began in other areas.
Despite efforts in court to make Chisso Corporation responsible for their actions in knowingly poisoning the waterways and environment with mercury and other chemicals, they have only had to make small payments to deceased victims and survivors.
There are still lawsuits ongoing against Chisso Corporation in regards to the mercury poisoning.
There is little compensation or assistance to the victims of Chisso Corporation's wastewater practices. Many victims are isolated from their communities.


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