Minamata disease
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Minamata disease is a neurological syndrome caused by severe mercury poisoning. Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing of the field of vision and damage to hearing and speech. In extreme cases, insanity, paralysis, coma and death follow within weeks of the onset of symptoms. Minamata disease was first discovered in Minamata city in Kumamoto prefecture, Japan in 1956. It was caused by the release of methyl mercury in the industrial waste from the Chisso Corporation's chemical factory. Over 2,250 victims have been officially certified (1,400 of which have died) and another 10,000 have received financial compensation from Chisso. It is estimated that over 2 million people may have eaten contaminated fish from Minamata Bay.
In Japan, it is sometimes referred to as Chisso-Minamata Disease. It is one of the Four Big Pollution Diseases of Japan.
History
Background
The Chisso Corporation first opened a chemical factory in Minamata in 1908. Initially producing fertilisers, the factory followed the nationwide expansion of Japan's chemical industry, branching out into production of acetylene, acetaldehyde, acetic acid, vinyl chloride and octanol, among others. The Minamata factory became the most advanced in all Japan, both before and after World War II. The waste products resulting from the manufacture of these chemicals were released into Minamata Bay in the factory effluent. Inevitably these pollutants had an environmental impact. Fisheries were damaged in terms of reduced catches and in response the Chisso Corporation agreed two separate compensation agreements with the fishery cooperative in 1926 and 1943.
The rapid expansion of the Minamata factory spurred on the local economy and as Chisso prospered, so did Minamata. This fact, combined with the lack of other industry, meant that Chisso had great influence in Minamata. Minamata was even dubbed as Chisso's "castle town", in reference to the capital cities of feudal lords who ruled Japan from the 16th to 19th century. At one stage over half of the tax revenue of Minamata City authority came from the Chisso Corporation.Masazumi, Harada. (1972). Minamata Disease. Kumamoto Nichinichi Shinbun Centre & Information Center/Iwanami Shoten Publishers. ISBN 4-87755-171-9 C3036.
The Chisso Minamata factory first started acetaldehyde production in 1932, producing 210 tons that year. By 1951 production had jumped to 6,000 tons per year: over 50% of Japan's total output. The chemical reaction used to produce the acetaldehyde used mercury sulfate as a catalyst. A side reaction of the catalytic cycle lead to the production small amount of an organic mercury compound, namely methyl mercury.[Mercury Technology Services, Information on Mercury] This highly toxic compound was released into Minamata Bay from the start of production in 1932 through to 1968 when this production method was discontinued.
Discovery
On April 21st, 1956, a five-year-old girl was examined at the Chisso Corporation's factory hospital in Minamata, Japan, a town on the west coast of the southern island of Kyushu. The physicians were puzzled by her symptoms: difficulty walking, difficulty speaking and convulsions. Two days later her younger sister also began to exhibit the same symptoms and she too was hospitalised. The girl's mother informed doctors that her neighbour's daughter was also experiencing similar problems. After a house-to-house investigation eight further patients were discovered and hospitalised. On May 1st, the hospital director reported to the local public health office the discovery of an "epidemic of an unknown disease of the central nervous system", marking the official discovery of Minamata disease.
In order to investigate the epidemic the city government and various medical practitioners formed The Minamata Strange Disease Countermeasures Committee at the end of May, 1956. Due to the localised nature of the disease, it was suspected to be contagious and as a precaution patients were isolated and their homes disinfected. Unfortunately, this contributed to the stigmatisation and discrimination experienced by Minamata victims from the local community. During their investigations the committee uncovered suprising anecdotal evidence of the strange behaviour of cats and other wildlife in the areas surrounding patient's homes. From approximately 1950 onwards cats had been seen to have convulsions, go mad and die. Locals called it the "cat dancing disease", owing to their erratic movement. Crows had fallen from the sky, seaweed no longer grew on the sea bed and fish floated dead on the surface of the sea. As the extent of the outbreak was understood, the committee invited researchers from Kumamoto University to help in the research effort.
The Kumamoto University Research Group was formed on August 24th, 1956. Researchers from the School of Medicine began visiting Minamata regularly and admitted patients to the university hospital for detailed examinations. Gradually a more complete picture of the symptoms exhibited by patients was uncovered. The disease developed without any prior warning, with patients complaining of a loss of sensation and numbness in their hands and feet. They became unable to grasp small objects or fasten buttons. They could not run or walk without stumbling, their voices changed in pitch and many patients complained of difficulties seeing, hearing and swallowing. In general these symptoms deteriorated and were followed by severe convulsions, coma and eventually death. By October 1956, 40 patients had been discovered, 14 of which had died: an alarming mortality rate of 36.7%.
Researchers from Kumamoto University also began to focus on the cause of the strange disease. They identified that the victims were clustered in fishing hamlets along the shore of Minamata Bay, often affecting members of the same family. The staple food of victims was invariably fish and shellfish from Minamata Bay and that the cats in the local area, who tended to eat scraps from the family table, had died with symptoms similar to those now discovered in humans. This lead the researchers to believe that the outbreak was caused by some kind of food poisoning, with contaminated fish and shellfish the prime suspects.
On November 4th the research group announced their initial findings: "[Minamata disease] is rather considered to be poisoning by a heavy metal... presumably it enters the human body mainly through fish and shellfish."
As soon as the investigation identified a heavy metal as the causal substance, the effluent from the Chisso plant was immediately suspected as the origin. The company's own tests revealed that their effluent contained more than ten poisonous substances including lead, mercury, manganese, arsenic, selenium, thallium, copper, magnesium oxide and potassium oxide. Identifying which poison in particular was responsible for the disease proved to be extremely difficult and time consuming. During the years 1957 and 1958 many different theories were proposed by different researchers. Initially manganese was thought to be the causal substance due to the high concentrations found in fish and shellfish and in the organs of the deceased. Thallium, selenium and a multiple contaminant theory were also proposed but it wasn't until March 1958, when visiting British neurologist Douglas McAlpine suggested that Minamata symptoms resembled those of organic mercury poisoning, that the focus of the investigation centred on mercury.
In Februrary 1959 the mercury distribution in Minamata Bay was investigated. The results shocked the researchers involved. Large quantities of mercury were detected in fish, shellfish and sludge from the bay. The highest concentrations were centred around the Chisso factory effluent canal and decreased going out to sea, clearly identifying the plant as the source of contamination. At the mouth of the effluent canal a figure of 2 kg of mercury per ton of sediment was measured: a level which would be economically viable to mine.
Hair samples were taken from the victims of the disease and also from the Minamata population in general. In patients the maximum mercury level recorded was 705 ppm (parts per million), indicating very heavy exposure. In Minamata residents the level was 191 ppm compared to an average level of 4 ppm for people living outside the Minamata area.
On November 12, 1959 a committee from the Ministry of Health and Welfare official published their results:
During the investigation by researchers at Kumamoto University, the causal substance had been identified as a heavy metal and it was widely presumed that the Chisso plant was the source of the contamination. Chisso was coming under closer scrutiny and in order to deflect critism the effluent output route was changed. Chisso knew the environmental damage caused by their effluent (reflected in their previous compensation payments to the fishing cooperative) and also knew that the effluent was the prime suspect in the Minamata disease investigation. Despite this, from September 1958, instead of discharging their waste into Hyakken Harbour (the focus of investigation), the effluent was discharged directly into Minamata River. The immediate effect was the death of fish at the mouth of the river, and from that point on new Minamata victims began to appear in other fishing villages up and down the coast of the Shiranui Sea, as the pollution spread over an even greater area.
Disgruntled local fishermen, who could no longer sell their fish, forced their way into the Chisso plant on August 6th, 12th, and 17th, 1959. These acts of defiance brought the issue to Japanese public attention. They demanded the installation of purification facilities at the plant and further compensation for their loss of livelihood. In response Chisso installed a Cyclator purification system. Testimony at a later trial proved that Chisso knew the Cyclator to be completely ineffective at removing mercury from the effluent. Yet the Cyclator was opened with a special ceremony in December 1956, with Chisso's president daring to drink water supposedly treated through the Cyclator.
Chisso also failed to co-operate with the investigation team from Kumamoto University. They actively withheld information on their industrial processes, leaving researchers to speculate what products the factory was producing and by what methods. The Chisso factory's hospital director, Dr. Hosokawa, established a laboratory in the research division of the plant to carry out his own experiments into Minamata disease in July 1959. Food to which factory effluent had been added was fed to healthy cats. 78 days into the experiment a cat exhibited symptoms of Minamata disease and pathological examinations confirmed a diagnosis of organic mercury poisoning. The company did not reveal these significant results to the investigators.
A theory of dumped military explosives contaminating the bay was put forward by Chisso's Executive Director Oshima. Investigators looked into the theory, discovered it to be untrue and stated that it was "contrary to the facts and ignored basic rules of medical science." Chisso also encouraged research into alternative possible causes of the disease, other than its own waste. Professor Kiyoura proposed amines as the cause of the disease and a paper from Professor Tokita supported the theory and further hypothesised that eating rotten fish might be the source. These papers were not regarded well by the medical and scientific community, although caused they much excitement in the press and confusion among victims and their families.[Soshisha, The Supporting Center for Minamata Disease]
In total, more than 900 people died in severe pain due to the poisonings. As of 2001, research indicated that as many as two million people may have been affected by eating contaminated fish. In the same time frame, 2,955 people had been certified as suffering from Minamata disease. Of these, 2,265 had been living on the coast of the Yatsushiro Sea.
In addition to pain and suffering as a direct result of the disease, the victims also endured discrimination and ostracism, mainly out of a fear that the disease was communicable. Furthermore, since Chisso is such an important company in the local economy, some victims were discriminated against, even harassed, by those loyal to and dependent on the company. Compensation of the victims led to further strife in the community, including unfounded accusations that some of the people who sought compensation did not actually suffer from the disease.[Ten Things to Know about Minamata Disease]
Many solutions were sought to compensate the victims while not bankrupting Chisso. The first wave of compensations, settled in 1959, could not be maintained as new cases of Minamata disease began to appear. These victims and their families were not included in the original settlement with Chisso and therefore, did not receive the same compensation as those diagnosed before the original solution. So the newly diagnosed families began the quest to receive comparable compensation for their disabilities. One group chose to sue Chisso and therefore go to trial for their compensation. Another group sought direct negotiations with the executives of Chisso.
These direct negotiations in Tokyo were exhausting. On December 8, Kawamoto, a leader in the direct negotiations group, began by asking Shimada, a Chisso executive, to pledge in their blood to come to an agreement and treat each other as human beings. Shimada refused. The negotiations lasted through much of the night, ending with Shimada collapsing and being taken to the hospital. The Minamata patients were told to go home, and when Shimada was able to negotiate again, he would do so in Minamata. However, the patients remained in the Chisso headquarters. By December 25, only two patients remained in Tokyo, Kawamoto and Sato. Chisso Executive Director Kuga, approached them and asked for them to take some money and buy tickets back to Minamata. Kawamoto and Sato refused unless Chisso agreed to direct negotiations. They were thrown out to the unsightly tented settlement outside of the building.
After this, protests and speeches by the patients took place outside of the Chisso office building. Media coverage was wide spread and many journalists took the side of the Minamata victims. Patients were shown in wheelchairs at the protests and in newspapers. However, the stalemate remained.
Patients and sympathizers marched on the downtown offices of Chisso and attempted to march as far as the president’s office. They were met with iron bars blocking the door to the Chisso floor of the Tokyo Building. The patients used the bars to their advantages by building memorials to the people who had already died of Minamata disease.
Because of the mass of media coverage, the Japanese Communist and Socialist parties began to more openly support the sufferers of Minamata disease along with the Sohoyo labor federation. The attention of the media and political party officials allowed Minamata disease to become a widely known dilemma in Japan and because the minority population of Minamata disease sufferers then had a voice, it then allowed Japanese democracy to develop to a new level. Also, due to this open support by opposing parties, and the call from the labor union for Chisso to negotiate, the Japanese government stepped into action by the Director General of the Environmental Agency (Oishi Buichi) asking to be allowed to mediate the negotiations.
Also around this time, Governor Sawada Issei came to Tokyo to help in overcoming the impasse of negotiations. Sawada and Oishi both met with the patients, Kawamoto and Sato, and also with Shimada, who had returned from the hospital. Both parties agreed to mediate negotiations through Sawada and Oishi.
As the negotiations began, the patients opposed a settlement mirroring that of the first solution. They not only wanted equal and sufficient compensation, but also for Chisso to publicly accept responsibility for the Minamata disease.
During these negotiations and also talks of a compensation advance, 29 more patients were diagnosed with Minamata disease. These newest patients were more cooperative with Chisso and agreed to accept a low compensation of $570 each. This caused a split between the newly diagnosed families. It also took away much of the leverage the direct negotiation group had and gave Chisso an advantage. The division between the Tokyo group and the Minamata group brought up hard feelings. Those in Minamata had continued to work, while the protestors in Tokyo had received financial support from backers in Tokyo. Many of those in Minamata were facing continued discrimination, but also were being threatened of losing their jobs if they continued with the negotiations. Only four people ultimately decided to drop the negotiations.
The patients reduced their demands to close to what the first settlement between Chisso and the original Minamata victims had been. However, Chisso still refused because of the lack of a ranking system for the severity of illness. Then the negotiations were officially suspended, due to Chisso’s unwavering stance.
Finally, the trial verdict came down in favor of the patients. The District Court found Chisso guilty of corporate negligence and ordered Chisso to pay $66,000 for each patient who had already died, between $59,000 and $66,000 for surviving patients, coming to a total of $3.44 million.
This gave the direct negotiations patients grounds to reach agreements. After days of agreements, Chisso agreed to pay $66,000 for deceased patients who were included in the group of newly diagnosed patients. This opened the door for the other newly diagnosed patients to be included in the trial settlement. Finally, on July 9, 1973, through the work of the new Environment Agency Director Miki, an agreement was reached. This proposal included the compensations based on ranking severity of symptoms, but also payments to the patients per year to cover living expenses, and payment of all medical expenses. The government also provides medical examinations for people living in the affected area. These compensations and actions are considered inadequate by many.
According to Timothy S. George, the environmental protests that surrounded the disease appeared to aid in the democratization of Japan. When the first cases were reported (or more accurately suppressed) the victims had no rights and were given no compensation. Instead, the afflicted were ostracized from their community due to ignorance about the disease; people were afraid that it was contagious.
Some patients and government officials eventually discovered that mercury poisoning was causing the disease, and were able to trace the disease to the consumption of fish near the Nitchitsu factory which dumped the mercury, no action was taken to solve the problem since the fisherman and victims represented a poor minority without an influential voice.
The people directly impacted by the pollution of Minamata Bay were not originally allowed to participate in actions that would affect their future. Disease victims, fishing families, and company employees were excluded from the debate. Progress occurred when Minamata victims were finally allowed to come to a meeting to discuss the issue. As a result, postwar Japan took a small step towards democracy. One reason may be because after Japan's defeat in World War II, the factory was part of the new zaibatsu that was determined to be more important to the livelihoods of its poorest citizens.
Through the evolution of public sentiments, the victims and environmental protestors were able to acquire standing and proceed more effectively in their cause. The involvement of the press also aided the process of democratization because it caused more people to become aware of the facts of Minamata disease and the pollution that caused it.
Although the environmental protests did result in Japan being more democratized, it did not completely rid Japan of the system that first suppressed the fishermen and victims of Minamata disease.
Photographic documentation of Minamata started in the early 1960s. One photographer who arrived in 1960 was Shisei Kuwabara, fresh out of university and photo school; the first exhibition of his work in Minamata was held in the Fuji Photo Salon in Tokyo in 1962, and the first of his book-length anthologies was published in Japan in 1965; he has returned to Minamata again and again since then.
However, it was a dramatic photographic essay by W. Eugene Smith that brought world attention to Minamata disease. The most famous photo of the essay, Tomoko Uemura in Her Bath, (1972) shows a woman, Ryoko Uemura, holding her severely deformed daughter, Tomoko, in a bath. Tomoko was poisoned by organic mercury compounds while still in the womb. The photo was very widely published. It was posed by Smith with the cooperation of Ryoko and Tomoko in order to dramatically illustrate the consequences of the disease. (It has subsequently been withdrawn from circulation at the request of Tomoko's family, and therefore does not appear in recent anthologies of Smith's works.)
The publicity of the Minamata disease also helped strengthen the environmentalist movement and bring up concerns about mercury poisoning.
From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.Investigation
Finding the cause
Identification of mercury
Chisso's corporate attitude
Victims
Compensation
Democratizing effects
Media
Second Outbreak
The , one of the Four Big Pollution Diseases of Japan, was confirmed in 1964. Identical in symptoms to the Kumamoto Prefecture's Minamata Disease, the second outbreak was confirmed with the same name. Since the outbreak's occurance among its patients occured in the Lower Agano River Basin in the Niigata Prefecture, sometimes this outbreak is called the or the .Cause
The source of the cause was the Kanose Plant, located in the Kanose Village, East Kanbara District, Niigata Prefecture (now part of Aga Village). The cause of the organic mercury poisoning was the untreated methylmercury waste solution generated during the production of acetylaldehyde, disposed into the Agano River, which was bio-accumulated up the food-chain from the fish caught from the river.Progress
When the patients filed a damages suit, Shōwa Electrical Works claimed, "The cause [of the outbreak] was the agricultural chemical run-off entering the riverway after the Niigata Earthquake." A family-member of the deceased patient testified in court, "My father was crazed like a wild beast and then died—agonized, in pain... like a dog."References
Further Reading
See also
External links
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