Itai-itai disease

'it hurts-it hurts disease') was the name given to the mass cadmium poisoning of Toyama Prefecture, Japan, starting around 1912.

The term "itai-itai disease" was coined by locals[1] for the severe pains (Japanese: 痛い itai) people with the condition felt in the spine and joints.

Starting in 1910 and continuing through 1945, cadmium was released in significant quantities by mining operations, and the disease first appeared around 1912.

[1] In the 1920s, levels of contaminated tailing waste increased after the creation of new froth flotation processes that boosted zinc production.

[6] Sphalerite, the main zinc containing ore in Komioka, is almost always coupled with greenockite, the only major cadmium-containing mineral in the world.

[6] Up until 1948, cadmium was discarded as waste into the Jinzū River due to it being of no industrial value, exacerbating the levels of the element's release into the waterbody.

The river was used mainly for irrigation of rice fields, but also for drinking water, washing, fishing, and other uses by downstream populations.

In 1968, the Ministry of Health and Welfare issued a statement about the symptoms of itai-itai disease caused by the cadmium poisoning.

[1] The mines are still in operation and cadmium pollution levels remain high, although improved nutrition and medical care has reduced the occurrence of itai-itai disease.

[7] Over time, the cadmium that was released as industrial waste began to accumulate in the soil, algae and river organisms.

[11] The local residents’ consumption of this rice and drinking water then resulted in elevated cadmium body burdens – leading directly to symptoms characteristic of itai-itai disease.

29 plaintiffs, consisting of nine people with itai-itai disease and 20 of their family members, sued the Mitsui Mining and Smelting Co. in 1968 in the Toyama Prefectural court.

[6] People who believe that they have itai-itai disease have to contact the Japanese Ministry of Health, Labor, and Welfare to have their claims assessed.

A person is considered to have itai-itai disease if he or she lived in the contaminated areas, has kidney dysfunctions and softening of the bones, but not related heart problems.

The water and solids are separated and processed before leaving the mine to ensure no groundwater contamination to the surrounding area.

The treatment facilities' exhaust is also monitored to ensure the absence of cadmium in the airborne byproduct of the zinc refining process.

As a response to the metal pollution, the Japanese government enacted the Prevention of Soil Contamination in Agricultural Land Law of 1970.

Surveying in Toyama Prefecture began in 1971, and by 1977, 1,500 hectares (3,700 acres) along the Jinzū River were designated for soil restoration.