Fifty years have passed since the first official recognition of Minamata disease, a major symbol of Japan’s postwar industrial pollution. Yet relief for those who suffered massive organic mercury poisoning, dating back to the 1950s and ’60s, has not been fully delivered. More than 3,700 people have filed application with local governments for official recognition as Minamata disease patients and some 1,000 others have filed lawsuits against the state and Chisso Corp., which released the pollutant into the environment. This means that nearly 5,000 people are waiting for some kind of decision that will compensate them for their suffering. The government must break the deadlock soon.

Minamata disease paralyzes the central nervous system and causes such symptoms as persistent headaches, mental confusion, limb paralysis, walking difficulties and convulsions. Minamata disease first appeared after methyl mercury was released by chemical maker Shin-Nippon Chisso Hiryo K.K., the predecessor of Chisso Corp., into Minamata Bay in Kumamoto Prefecture. Methyl mercury is waste from the process to produce acetaldehyde, a plasticizing agent. Many people who ate fish contaminated with organic mercury developed the disease. Some people were born with the disease.

As of the end of March, 2,955 people in Kumamoto, Kagoshima and Niigata prefectures had been officially recognized as patients of the disease, and 2,009 of them have already died, according to the Environment Agency. Some 15,000 others have applied for recognition but to no avail. Experts familiar with the disease estimate that the real number of latent sufferers is probably much larger, reaching several tens of thousands.

On May 1, 1956, a local public health center in Minamata received a report that four people showed symptoms of an unexplained brain disorder termed merely a “strange disease.” That date is regarded as the first day that Minamata disease surfaced. It took more than 10 years before the government recognized cause of the disease as industrial pollution. In 1965, people suffering from similar symptoms were found along Agano River in Niigata Prefecture (these cases later identified Second Minamata disease or Niigata Minamata disease). In September 1968, Minamata disease was officially recognized as a result of industrial pollution — four months after Chisso stopped production of acetaldehyde.

In March 1973, Minamata disease patients won a historic compensation lawsuit against Chisso. It wasn’t till October 2004, though, that the Supreme Court found the central and Kumamoto prefectural governments guilty of failing to take appropriate action to prevent the spread of Minamata disease after January 1960. In awarding a total of 71.5 million yen in compensation to 37 plaintiffs who had moved to the Kansai region from Kumamoto and Kagoshima prefectures, the top court said a person with even a single symptom of mercury poisoning should be recognized as a Minamata disease patient if he or she met certain other conditions. Thus it set less rigid criteria for recognizing Minamata disease victims than those set by the central government in 1977. This has led to the existence of two different sets of criteria for recognizing victims, leading to confusion.

Some members of the Minamata disease victim screening panels in Kumamoto, Kagoshima and Niigata prefectures have declined to be reappointed because they realized that if they refused to recognize the disease in some people, those people could still go to court to win recognition as patients and receive compensation, regardless of their expert opinion. Thus the screening process for more than 3,700 people has been stalled and about 1,000 others have filed lawsuits.

The Environment Agency has set up an experts’ forum on the Minamata disease issue. Some forum members are calling for a change in the government’s criteria so that the conflict between the two sets can be resolved. The ministry resists such a call because it fears that such a change could be incongruous with the 1995 “political reconciliation” program with latent Minamata disease patients, carried out under the administration of socialist Prime Minister Tomiichi Murayama.

Depending on the degree of suffering, about 12,000 people have received either a lump sum payment of 2.6 million yen plus total medical expenses or partial medical expenses. These people are not “recognized” as Minamata disease patients, and have agreed not to file compensation lawsuits.

Whatever the stance of the Environment Agency, a large number of people still live with the symptoms of Minamata disease. The ministry should review the current patient recognition and compensation system and revise it to help them. It is also hoped that the experts’ forum will come up with proposals that will lead to a change in the ministry’s thinking.

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