Minamata disease

A disorder caused by methyl mercury poisoning that was first described in the inhabitants of Minamata Bay, Japan and resulted from their eating fish contaminated with mercury industrial waste. The disease is characterized by peripheral sensory loss, tremors, dysarthria, ataxia, and both hearing and visual loss. Even the unborn child is at risk from Minamata disease. Methyl mercury readily crosses the placenta from mother to fetus and is damaging, particularly to the developing brain. Children born with Minamata disease can have growth deficiency, microcephaly (an abnormally small head), severe mental retardation and be deaf and blind. Minamata disease has not been confined to Minamata where the source of the mercury was primarily from eating fish caught in the contaminated Bay. Other sources of maternal exposure to methyl mercury have included flour made from seed grain treated with methyl mercury (which affected at least 6,500 people in Iraq) and meat from animals raised on mercury-tainted grain (in New Mexico, USA).

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Min·a·mata disease .min-ə-'mät-ə- n a toxic neuropathy caused by the ingestion of methylmercury compounds (as in contaminated seafood) and characterized by impairment of cerebral functions, constriction of the visual field, and progressive weakening of muscles

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a form of mercury poisoning (from ingesting methyl mercury in contaminated fish) that caused 43 deaths in the Japanese coastal town of Minamata during 1953-56. The source of mercury was traced to an effluent containing mercuric sulphate from a local PVC factory. Symptoms include numbness, difficulty in controlling the limbs, and impaired speech and hearing.

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symptoms of alkyl mercury poisoning that were seen between 1953 and 1958 among persons who ate seafood from a bay in Japan that was polluted with alkyl mercury compounds; it consisted of a severe neurologic disorder usually characterized by peripheral and circumoral paresthesia, ataxia, dysarthria, and loss of peripheral vision, which led to severe permanent neurologic and mental disabilities and sometimes death.