Environmental pollution in Japan has accompanied industrialization since the Meiji period. One of the earliest cases was the copper poisoning caused by drainage from the Ashio Copper Mine in , beginning as early as 1878. Repeated floods occurred in the Watarase River basin, and 1,600 hectares of farmland and towns and villages in Tochigi and Gunma prefectures were damaged by the floodwater, which contained excessive inorganic copper compounds from the Ashio mine. The local farmers led by Shozo Tanaka, a member of the Lower House from Tochigi appealed to the prefecture and the government to call a halt to the mining operations. Although the mining company paid compensatory money and the government engaged in the embankment works of the Watarase river, no fundamental solution of the problem was achieved.
Japan is the world's leading importer of both exhaustible and renewable natural resources and one of the largest consumers of fossil fuels.
Current Japanese environmental policy and regulations were the consequence of a number of environmental disasters in 1950s and 1960s. Cadmium poisoning from industrial waste in Toyama Prefecture was discovered to be the cause of the extremely painful itai-itai disease (イタイイタイ病 Itai itai byō?, lit. "ouch ouch sickness"). People in Minamata City in Kumamoto Prefecture were poisoned by methylmercury drained from the chemical factory, known as the Minamata disease. The number of casualties in Minamata is 6,500 as of November 2006.