Text size
Yellow text on a blue background
Black text on a yellow background
Yellow text on a black background


  • Enquiries
  • Site map

For the future of the Earth

Home > Outline of Japan's Industrial Pollution Abatement > Preventative Measures Against Water Pollution Jinzu River, Toyama Prefecture > 1) Discover of the itai-itai disease

Main content starts here.

Update:April 1, 2010

1) Discover of the itai-itai disease


The strange disease that appeared in the downstream basin of the Jinzu River around 1912 was called by locals "itai-itai byo" ("itai" being what Japanese people say when infilicate with pain and "byo" literally meaning disease). In came by this name because of the way victims cried out "itai-itai" under the excruciating pain they endured. Women were mostly afflicted with pain across their entire body and more severe cases suffered broken bones when trying to move on their own. However, because the disease was first taken as an endemic sickness, it wasn't until the 1950's that outright research began.

Response began in 1955 when Shogo Hosoya announced that the "disease was caused by a microorganism" and that "disease was new to Japan". Mass-communication spread the news of the "itai-itai disease" across the country.
In 1956, Noboru Hagino announced his opinion that the "ttai-itai disease was a form of bone brittleness (osteomalacia) that came from malnutrition." But later, the fact that the outbreak was concentrated in a limited area along the 3fnzu River basin, lead him to announce his explanation that the "itai-itai disease was chronic cadmium poisoning caused by heavy metals such as zinc and lead contained in water of the Jinzu River."
In 1961, Toyama Prefecture set up a special council for dealing with the disease which was responsible for pinpointing the cause and its preventative measures. In 1963, the Ministry of Health and Welfare and the Ministry of Education respectively set up a medical research council and medical research team amongst research institutes, marking the start of government-directed inquiry and research into the cause.
Based on results from these studies, in May 1968, the Ministry of Health and Welfare officially announced that the "itai-itai disease was chronic cadmium poisoning. It first impairs kidney function and progressively causes osteomalacia. Victims suffer from calcium deficiency as occurs "with old age, malnutrition', hormone imbalance and when pregnant or breast feeding." The report followed that the cadmium came from none other than the "upstream discharge into the Jinzu River by commercial activities of the Kamioka Mining Co., Ltd. at their Kamioka Mines."