It is a neurological syndrome caused by mercury poisoning. The symptoms include numbness in the hands and feet, muscle weakness, damage of hearing and speech, and narrowing the field of vision.
Polio
Polio is an infection caused by a virus, called the poliovirus. The poliovirus is spread by infected water or direct contact with a person. The poliovirus invades the nervous system and can cause irreversible paralysis in a matter of hours.
Rickets
Lack of vitamin D results in reduced absorption of calcium and phosphorus. Rickets causes a child's bones to become soft and weak, which can lead to bone deformities.
Itai-Itai disease
It is cadmium poisoning and causes the softening of bones and kidney failure. It was first reported in Toyama Prefecture, Japan in 1912. It is one of the Four big pollution diseases in Japan with Minamata, Niigata Minamata, and Yokkaichi Asthma.