was director of the company hospital attached to the

Chisso Corporation The , since 2012 reorganized as JNC (Japan New Chisso), is a Japanese chemical company. It is an important supplier of liquid crystal used for LCDs, but is best known for its role in the 34-year-long pollution of the water supply in Minamata, Ja ...

's chemical factory in

Minamata is a city located in Kumamoto Prefecture, Japan. It is on the west coast of Kyūshū and faces Amakusa islands. Minamata was established as a village in 1889, re-designated as a town in 1912 and grew into a city in 1949. As of March 2017, the ...

Kumamoto prefecture is a Prefectures of Japan, prefecture of Japan located on the island of Kyūshū. Kumamoto Prefecture has a population of 1,748,134 () and has a geographic area of . Kumamoto Prefecture borders Fukuoka Prefecture to the north, Ōita Prefecture to ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

. He was the first doctor to discover and treat patients of the massive outbreak of

mercury poisoning Mercury poisoning is a type of metal poisoning due to exposure to mercury. Symptoms depend upon the type, dose, method, and duration of exposure. They may include muscle weakness, poor coordination, numbness in the hands and feet, skin rashe ...

that occurred in the town, which became known as

Minamata disease Minamata disease is a neurological disease caused by severe mercury poisoning. Signs and symptoms include ataxia, numbness in the hands and feet, general muscle weakness, loss of peripheral vision, and damage to hearing and speech. In extrem ...

Timeline

* 23 September 1901, born in Mikame village, Nishiuwa-gun,

Ehime prefecture is a prefecture of Japan located on the island of Shikoku. Ehime Prefecture has a population of 1,342,011 (1 June 2019) and has a geographic area of 5,676 km2 (2,191 sq mi). Ehime Prefecture borders Kagawa Prefecture to the northeast, Toku ...

. * 1927 Graduates from Tokyo University medical department. * 1936 Joins and is attached to the hospital of the Agochi factory on the Korean peninsular. * 1941 Appointed director of the Minamata factory hospital. * 1941 Assumes a new post as a field surgeon in

Burma Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...

. * 1947 Demobilizes and returns to work at the Minmata factory hospital. * 1950 The occupying forces order the dissolution of the

zaibatsu is a Japanese language, Japanese term referring to industrial and financial vertical integration, vertically integrated business conglomerate (company), conglomerates in the Empire of Japan, whose influence and size allowed control over signi ...

, including the Japan Nitrogenous Fertilizer Company. A successor company, is founded. * 1 May 1956 Reports the discovery of an "epidemic of an unknown disease of the central nervous system" to the Minamata local health office, marking the official discovery of

. * May 1957 Begins experimenting on cats in an effort to determine the cause of the disease. Factory

wastewater Wastewater is water generated after the use of freshwater, raw water, drinking water or saline water in a variety of deliberate applications or processes. Another definition of wastewater is "Used water from any combination of domestic, industr ...

is included in the cats' food. * October 1959 "Cat 400" exhibits signs of

. Hosokawa is convinced the factory's wastewater is the cause of

but under persuasion from the company, these results are not published. * 1962 Retires from the company and returns home to

* 1970 Hospitalised with

lung cancer Lung cancer, also known as lung carcinoma (since about 98–99% of all lung cancers are carcinomas), is a malignant lung tumor characterized by uncontrolled cell growth in tissue (biology), tissues of the lung. Lung carcinomas derive from tran ...

. While hospitalised he is interrogated for a judicial proceeding regarding Minamata disease and testifies to the concealment of the experimental results of "Cat 400". * 13 October 1970 Dies at the age of 69.

External links

Biography
People from Ehime Prefecture Japanese surgeons 1901 births 1970 deaths Minamata disease Japanese healthcare managers Deaths from lung cancer in Japan 20th-century Japanese physicians {{Japan-med-bio-stub