Minamata disease

The Minamata disease (in Japanese水 俣 病, Minamata byō ) is a chronic poisoning by organic mercury compounds (mercury poisoning), which occurred for the first time mid-1950s along the Japanese Yatsushiro Sea in the vicinity of the town of Minamata. Symptoms are initially only fatigue, headache and body aches, later ataxia, paralysis, psychosis, in severe cases, coma. The disease then ended up not infrequently fatal.

Minamata was this world to the concept of environmental damage caused by uncontrolled dumping of waste, as in the village mid-1950s showed damage to the central nervous system of humans and animals, which could be attributed to the ingestion of mercury compounds from food and drinking water soon. The chemical company Chisso, which maintained a acetaldehyde plant at the site, initially denied any connection, even though he had already established in -house test series that the waste water from the acetaldehyde production exactly caused the symptoms observed in animals. The mercury compounds can be used as a catalyst for the preparation of acetaldehyde.

Only after a government investigation of the company had to admit that the introduction of methylmercury iodide into the sea water had a dramatic accumulation of mercury compounds in the seaweed and thus in the fish, the main food of the inhabitants of the coastal town, out. According to current estimates, about 17,000 people were injured more or less seriously by the mercury compounds, but by 2000 only 2,265 people were officially recognized as victims of Minamata disease. About 3,000 are likely to have died of poisoning.

Major contribution to the publication and finally resolving the matter had the photo essays of W. Eugene Smith, who lived several years in Minamata and photographed and published his photos in Life and in a book, as well as the Japanese writer Michiko Ishimure with the book paradise in the sea the agony and the Japanese documentary filmmaker Noriaki Tsuchimoto with his 1971 released movie Minamata - the victims and their disease.

1964 A second case of such a mass disease in Japan occurred on River Agano in Kanose (now Aga ) in Niigata Prefecture, where the company Showa Denko entertained the same production process as Chisso in Minamata ( Niigata Minamata disease (新泻 水 俣 病, Niigata Minamata byō ), also second Minamata disease (第二 水 俣 病, Dai -ni Minamata byō ) below). Other cases of Minamata disease occurred along the Songhua River in China, Canada and Tanzania. 1999 could prove the Minamata disease, Japanese scientists also with Indians in the Amazon. Here illegally arrived mercury at gold panning in the river water.

Global Programme of the United Nations

The United Nations have in your United Nations Environmental Program Governing Council of mercury since 2001 on the list of regulated substances in the global environment pollution. 2013, the Minamata Convention to curb mercury emissions was signed.

Epidemiological studies

For several years, epidemiological studies are increasingly being conducted to explore the neurophysiological effects of low-threshold exposures to mercury. Thus, a prospective study of 1,700 mother / child pairs were created from 2006 to 2011 in the Mediterranean, where mercury and other metals in maternal hair samples and Nabelschnurblutpoben were measured. 18 months after birth, the neurological development of children, according to the Bayley Scale ( 3rd edition ) was determined. The hope of the authors is that of the planned Folge-/Langzeituntersuchungen a better understanding of the neurophysiological effects of mercury and other elements in children is achieved.

See also: Itai Itai disease ( chronic cadmium poisoning)