Na June 1971, ụlọikpe ahụ chọpụtara na Mitsui Mining and Smelting Co. bụ onye ikpe. N'ikpeazụ, ụlọ ọrụ ahụ rịọrọ n'ụlọikpe Nagoya District Court dị na Kanazawa, ma a jụrụ arịrịọ ahụ n'August 1972. Mitsui Mining and Smelting Co. kwetara ịkwụ ụgwọ maka nlekọta ahụike nke ndị ahụ metụtara, na-akwụ ụgwọ maka nlekota nke mmiri mmiri nke ndị bi na ya mere, ma na-akwụghachi ndị nwere ọrịa ahụ ụgwọ. Ndị mmadụ kwenyere na ha nwere ọrịa itai-itai ga-akpọtụrụ Japanese Ministry of Health, Labour, na Welfare na-ekwu na ndị ha na-arịa ọrịa itai-itai. Ọtụtụ ndị nwere afọ ojuju na gọọmentị jụrụ ma ghara ịnakwere usoro nyocha maka ọgwụgwọ. Ajụjụ a mere ka gọọmentị gbanwee usoro nyocha nke onye ọrịa ahụ; Mgbe a jụrụ ajụjụ a: Mgbe gọọmentị gbanwere usoro nyocha nke onye ọrịa ahụ?
Ọgọst 1972