Central government, prefecture not responsible for Niigata mercury poisoning, court rules


The Niigata District Court has ruled that neither the central government nor the Niigata Prefectural Government was responsible for the neurological disorders caused by mercury poisoning decades ago.

Presiding Judge Yuko Otake on Monday also confirmed that seven of the 11 plaintiffs should be deemed as sufferers of the disease.

The ruling contrasts with Minamata disease in Kumamoto Prefecture, also caused by mercury poisoning, in which the central and prefectural governments were found partially responsible.

Otake ordered chemical maker Showa Denko K.K. to pay ¥3.3 million to ¥4.4 million in damages per person to the seven people, who had not been officially certified as victims of the disease. But the judge rejected damages claims against the central and prefectural governments.

The ruling was the first in 23 years on the disease in Niigata, which was officially recognized in 1965 following the official recognition of the outbreak of a similar disease in Kumamoto Prefecture, which came to be known as Minamata disease, in 1956.

Showa Denko’s plant in Niigata Prefecture released wastewater containing methylmercury into the Agano River, causing mercury poisoning among local people who ate fish caught in the river.

The 11 plaintiffs were demanding damages of ¥12 million per person.

None of past rulings related to the disease in Niigata have held the central government responsible.

“The ruling is unjust because it does not recognize the responsibility of the central and prefectural governments,” a lawyer for the plaintiffs said.

They said they will appeal the ruling.

The court deemed the seven plaintiffs as sufferers of the disease because they lived with family members who were officially recognized as victims.

But for the four other plaintiffs, the ruling did not recognize a direct links between their conditions and the methylmercury pollution, saying their symptoms may have stemmed from other diseases.

In denying the responsibility of the central government and the prefecture, Otake said, “It would have been difficult to know before the official recognition in 1965 that fish and shellfish in the river were polluted with methylmercury.”

The absence of wastewater regulations at the time should not be considered illegal, she said.

The plaintiffs — men and women in their 40s to 80s — claim to be suffering from dizziness and numbness in their limbs due to their past consumption of fish and shellfish polluted with methylmercury from the Showa Denko plant’s wastewater.

A law to provide redress to sufferers who have not been officially certified as victims of the diseases in Kumamoto and Niigata was enacted in 2009. This led some plaintiffs to drop out of this suit, but the 11 people continued the case with the aim of holding the central and prefectural governments responsible.