Itai-itai disease is a condition caused by long-term exposure to high levels of cadmium. Cadmium is a toxic heavy metal that can be found in industrial emissions, contaminated soil, and contaminated water sources. When cadmium enters the body, it accumulates in the kidneys and causes damage to the kidneys and bones. Itai-itai disease is characterized by severe pain in the joints and bones, as well as osteoporosis and fractures. This disease primarily affected individuals living near mining areas in Japan, where industrial waste containing cadmium was discharged into rivers. It is important to note that mercury, arsenic, and asbestos are all hazardous substances as well, but they are not directly associated with Itai-itai disease.