September 30, 2023

Tsuyoshi Masuda
President, Japan Federation of Democratic Medical Institutions

The Osaka District Court on September 27 ruled in favor of all 128 plaintiffs in the second “No More Minamata” lawsuit in the Kinki region seeking national compensation.

Recognizing all plaintiffs as suffering from Minamata disease, the ruling identified the credibility of a “Common Medical Certificate” for Minamata disease used by doctors, many of whom are our members, for examining patients and recording their symptoms faithfully. The court found the calculation of attributable fraction based on epidemiological studies highly credible. It also clearly recognized that many Minamata disease patients only exhibit four-limb dominant peripheral sensory disturbance or generalized sensory disturbance, abnormalities in two-point discrimination in the tongue, perioral sensory disturbance, concentric contraction of the visual field, or ataxia increase the probability of Minamata disease, and late-onset Minamata disease and fluctuations in symptoms exist. We have consistently stressed these details regarding the diagnosis of chronic Minamata disease.

The Japanese Society of Neurology, during the lawsuit underway in May 2018, released a statement in “response to opinion inquiry on neurological findings related to methylmercury toxicosis” at the request of the Environment Ministry. It denied large fluctuations in neurological symptoms and late-onset Minamata disease developing after a long period of time, defending the government’s claims without medical evidence. However, the court rejected these arguments and adopted the opinions and testimonies of the plaintiffs’ doctors, who had worked on clinical and investigative studies on Minamata disease. They made such efforts while these studies were neglected or done little for a long time by doctors who kept in step with the government’s stance.

The ruling paves the way for providing relief, beyond boundaries of areas and ages set under the Minamata disease special measures law, for patients who were not recognized as suffering from the disease under the government’s 1977 criteria (set in accordance with the pollution-related health damage compensation law) and those who were not eligible for relief under the special
measures law. This is a landmark decision that clearly and accurately recognizes such people as Minamata disease patients.

The national government and Kumamoto Prefecture should accept this ruling seriously, decide not to appeal it, swiftly give relief to all Minamata disease patients, and conduct health and long-term environmental studies in coastal areas of the Shiranui Sea.

We demand that the national government, Kumamoto Prefecture, and Chisso Corporation solemnly take this decision and make the utmost effort for early settlement in all Minamata disease lawsuits, including the ongoing “No More Minamata” cases in Kumamoto, Tokyo, and Niigata.