In 1964, a mysterious disease of unknown origin appeared among residents living in the Agano River basin in Niigata Prefecture, Japan. Eight months later, on September 26, 1968, the Japanese Ministry of Health and Welfare officially announced that the unusual illness was caused by mercury poisoning, stemming from industrial waste discharged by Showa Denko, a factory located 65 km upstream from the Agano River. To date, 2,665 victims of the Niigata incident have been identified, most of whom lived with incurable illnesses throughout their lives and have now mostly passed away.