May 1, 2016 marked 60 years since authorities officially recognized Minamata disease, known in Japan as the "original industrial pollution case." But the case is far from over, with many people still suffering the effects and waiting for official recognition as victims so that they can receive compensation. The government and chemical manufacturer Chisso Corp. must establish a framework in which all victims are provided relief.
On May 1, 1956, the director of a hospital affiliated with Chisso Corp.'s Minamata chemical plant in the Kumamoto Prefecture city of Minamata alerted the Minamata public health authorities that a patient was exhibiting unexplained neurological symptoms. This is said to be the first official recognition of Minamata disease.
The cause was found to be methylmercury generated in the process of producing acetaldehyde, an ingredient in manufacturing plastic and other products. Mercury-tainted water was dumped into local waters, which then polluted fish and other seafood. People who ate the contaminated seafood developed neurological disease from the toxins.
However, the central government was apprehensive about enforcing restrictions on a company that was essential to Japan's rapid economic growth, and it wasn't until 12 years later that it officially recognized Minamata disease. As a result, the government failed to prevent a similar outbreak of the disease in Niigata Prefecture.
The course taken by the government thus far has been haphazard, and relief measures have become extremely complicated. Those with Minamata disease are officially recognized as such based on the Act on Compensation of Pollution-related Health Damage. In the three affected prefectures of Kumamoto, Kagoshima and Niigata, some 3,000 people have thus far received recognition. At least 2,000 have applied for and are still awaiting official certification.
The number of officially recognized victims has not increased because recognition criteria are extremely stringent. In 1977, the government stipulated that victims must exhibit multiple symptoms centering on sensory dysfunction. Based on a 2013 Supreme Court ruling, the government issued a notice that victims with only sensory dysfunction would also be eligible for official recognition, but because the government demanded that the victims provide proof that they ingested methylmercury, recognition numbers have barely risen.
As for non-recognized Minamata patients, the government carried out relief measures twice: once in 1995, through a government settlement plan; and the other in 2009, through an act on special measures concerning victims of Minamata disease.
Those who have received official government recognition as Minamata disease patients receive a lump sum of 16 million to 18 million yen each, but the 1995 settlement plan only offered 2.6 million yen per patient, and the act on special measures only 2.1 million yen.
The government's certification criteria have effectively written off many Minamata patients. At least 1,000 patients who were deemed ineligible for relief under the 2009 act on special measures have filed suit against the government, among others, for damages.
Because the government has failed to conduct a thorough investigation, the overall picture of the Minamata disease case, including the scope of the damage caused by mercury and the symptoms caused by mercury ingestion, remain a mystery.
In March of this year, a group of Minamata disease patients demanded that the central government and Chisso Corp. conduct a health survey on residents of the Shiranui coast, centering on the city of Minamata, and review the Minamata disease certification criteria. It was a desperate demand brought 60 years after the first case was confirmed.
The Minamata disease case is not over. Not until the government pursues a comprehensive investigation on the damage that has been done, and re-establishes certification criteria that aligns with the current reality.