Shozo TANAKA, a member of the House of Representatives from Sano made enquiries at the parliament beginning in 1891, and the damages by the mining pollution became public throughout the nation.
佐野出身の衆議院議員田中正造は1891年以降、たびたび国会で鉱毒の質問を行い、鉱毒の害は全国に知れ渡った。