In May 1956, Minamata Disease was officially recognised. Four years beforehand, the Chisso Chemical Company dumped organic mercury waste into Minamata Bay. The mercury entered the food chain, massively concentrating on each step of the chain, so that people and animals that ate sufficient fish from the polluted bay were poisoned. The poisoning attacked the victim's central nervous system, which in turn led, in some cases, to brain damage, loss of physical co-ordination, fits, physical deformity, narrowing vision and loss of tactile sensation - among other symptoms. The organic mercury also attacked unborn children who were born with congenital mercury poisoning. The poisoning became known as Minamata disease, and became infamous as one of the worst cases of industrial poisoning of all times.