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Timeline of the unfolding mercury disaster

1889: Official designation of Minamata Village upon nationwide adoption of the Village system.(pop. 12,040)

1906: Shitagau Noguchi Sogi establishes Electric Co. (former Chisso Co.) in the Village of Okuchi, Isagun, Kagoshima Prefecture.

1908: Nippon Carbide Co. Begins manufacturing at Minamata Plan. Sogi Electric supplies electric power. Sogi Electric and Nippon Carbide merge and form Nippon Nitrogen Fertilizer Co. Ltd.. (hereafter called N. N.)

1912: Minamata Village is re-designated as Minamata Town.

1932: N. N. Minamata begins first stage operations of acetaldehyde compound acetic acid facilities.

1941: N. N. Minamata begins first production of vinyl chloride in Japan.

1949: City system adopted, becomes Minamata City. (pop. 42,270)

1950: N. N. Minamata becomes Shin Nippon Chisso Fertilizer Co., Ltd. (hereafter called SNC)

1956: Official discovery of Minamata disease: the director of SNC Hospital reports to the Minamata Public Health Center on an influx of patients with similar nervous system damage symptoms.

1963: The Kumamoto University Study Group makes its public official report concerning the causes of Minamata disease: "... causative agents of Minamata disease are methyl mercury compound extracted from shellfish caught in the bay and taken from sludge from the SNC plant. However, the extracted substances are slightly different in structure."

1965: SNC changes its name to "Chisso Co., Ltd." (hereafter called Chisso)

Official recognition of Niigata-Minamata disease: in Niigata, Drs. Tadao Tsubaki and Yukiaki Ueki report to the Dept. of Public Health of Niigata Prefecture that "patients of mercury poisoning from an unknown source are appearing in scattered areas downstream along the Agano River and coastal regions."

1968: Chisso Minamata stops production of acetaldehyde by the acetylene method.

Official recognition as a pollution: the Japanese government makes an official report concerning Minamata disease, affirming that the cause of Minamata disease is methyl mercury compound produced in the acetaldehyde acid facilities of Chisso Minamata factory.

1972: "Meisuien", a social welfare institute for the severely handicapped, opens. 13 congenital Minamata disease patients are admitted.

1975: Kumamoto Prefecture, Minamata City, and Minamata Fisheries Co-op give notice of voluntary catch restrictions in Minamata Bay.

1976: Kumamoto Prefecture establishes Minamata Disease Diagnosis Center and opens Minamata Bay Pollution Protection Office.

1977: Sludge Disposal Project begins. Dividing nets are set up to trap contaminated fish.

1978: Cabinet reaches consensus on issuance of prefectural bonds to Chisso. Establishment of the National Institute for Minamata Disease.

1983: Sludge Dredging Project in Minamata Bay begins

1987: Sludge Dredging Project in Minamata Bay ends.

1988: Supreme Court rejects the appeal of Minamata Disease Criminal Case. The president of Chisso and the director of Chisso Minamata Factory are sentenced guilty.

1989: Minamata City is designated one of the areas of the Regional Character Formation Project. Plan include the construction of Minamata Disease Museum and a memorial with "Environmental Model City, Minamata, with Love and Ease" as its theme.

The prefecture announces concrete plans for the active use of the reclaimed land in Minamata Bay, which will be completed by the end of March, 1990, focusing on Development Plans for the Reclaimed Land in Minamata Bay, and its Vicinity.

1990: Completion of Minamata Bay Pollution Protection Project directed by Kumamoto Prefecture.

1991: The Environment Agency opens a Special Committee for the Minamata Disease Issues in the Central Environment Council, the Environment and the Health Department for the purpose of discussing the special measures for Minamata disease victims and general measures to tackle Minamata disease for uncertified victims.

Special Committee for Environmental Measures in the prefectural assembly sets up the Special Committee for Minamata disease issues. Ground-breaking for Minamata Disease Municipal Museum which passes on the history of Minamata disease and its lessons.

1992: Minamata Disease Victims Memorial Service organized by Minamata City is held after 24 years. About 1,000 people including victim's families, patients, and citizens are present and pray for the lives sacrificed by Minamata disease.

1993: Minamata Disease Municipal Museum opens. Kumamoto Prefectural Environmental Education and Intelligence Center opens.

1994: The 3rd Minamata Memorial Victims Memorial Service is held. Mayor Yoshii first apologizes as the mayor of Minamata, saying that " We have not taken enough measures for the victims who have been discriminated against without any reason."

1995: The coalition ruling party sets up the Council for Measures on Minamata Disease. The Council for Measures on Minamata Disease presents an interim report on the solution for relief of unaided patients. The removal of the dividing nets in the Nananose Sea Area starts. Based on the proposal from Fukuoka High Court, Kumamoto Prefecture reaches a solution in which cash benefit depends on the injury level of the victim.

During his canvassing at Fukuoka, Prime Minister Murayama expresses his personal regret, stating that part of the blame in terms of the expansion of Minamata disease rests upon the government. It is the first statement of regret by a prime minister.

Environment Agency presents the final plan for the settlement which is equal benefit to every unaided patient. The final plan for the settlement with cash benefit to the victims' organizations and to the patient ( 2.6 million for each unaided patient) is officially presented. Environment Agency presents a rough plan for the financial support of Chisso and for the regional regeneration to Kumamoto Prefecture.

1996: The acceptance of the application for the Comprehensive Measures against Minamata Disease, based on the final plan for the settlement, begins. An exhibition of photographs recording the true face of the Minamata Disease situation is held in Paris by Jin Akutagawa and Shisei Kuwahara.

International Environment Forum in Minamata organized by Environment Agency, Kumamoto Prefecture, and Minamata City is held at the municipal Cultural Hall, and experts environmental problems discuss the theme, "Creating a city kind to the environment."

The 5th Minamata Disease Memorial Service is held with about 1,000 people on the reclaimed land of Minamata Bay, and the director-general of Environment Agency and the president of Chisso participate for the first time.

Yoshii, Mayor of Minamata states at the local assembly that Minamata City will continue to appeal to the national and prefectural governments for further assistance, and city itself aims for creating a city where people value environment and human cooperation.

Minamata Exhibition in Tokyo is held at a special place of Shinagawa Station, Tokyo. Opening ceremony of Minamata Memorial is held. The Ground-breaking of Southern Minamata Moyainaoshi Center.(Orange Center)

1997: Memorial Service Minamata Disease Victims. At the first Memorial Service since the government's solution to Minamata Disease, a prayer was offered to the victims of the disease along with the renewal of an oath for the regeneration and promotion of the region.

Results of the examination of fish and shellfish showing the level of mercury to be below safety levels for three consecutive years. The decision to remove the dividing nets in Minamata Bay was unofficially made.

"Declaration of Safety". Governor of Kumamoto Prefecture, Fukushima, declares safe the fish in Minamata Bay. A major turning point in the move towards the regeneration of the Minamata/Ashikita region.

The Minamata Fisheries Co-op agrees to the total removal of the dividing nets in Minamata Bay at a special general meeting. Work begins on the removal of the dividing nets. The Minamata Fisheries Co-op and Chisso sign the document confirming the completion of the removal of the dividing nets. Self-controlled restrictions on fishing in Minamata Bay are lifted. Fishing in the bay is re-opened for the first time in 24 years.

Monitoring of the fish and shellfish in Minamata Bay (post removal of the division nets) begins. Investigations will be carried out twice a year for the next three years.

"Exhibition of the Products of Minamata". The Minamata Fisheries Co-op participates for the first time. The "Happiness of the Sea" Fair is held and the safety of the fish and shellfish from Minamata Bay is promoted.

1998: The Minamata Moyainaoshi Centre (Moyaikan) is completed.

(reference 84)

See also: Amalgamation, Appliances, Chlor-Alkali, Dentistry, Explosives, Iraq poisoning, 'Mad as a Hatter', Mercury, Methylmercury, Minamata, Minamata timeline, Medical uses, Pigmentand organic fungicide production, Toxicology