front |1 |2 |3 |4 |5 |6 |7 |8 |9 |10 |11 |12 |13 |14 |15 |16 |17 |18 |19 |20 |21 |22 |23 |24 |25 |review

Possible effects to the improvement for environmental pollution have been made; removed of the contaminated sediments of the bay or the river floor, and monitoring of methylmercury levels in fish and wastewater. With regard to the Minamata plant of Chisso Co. Ltd., through the completion of total circulation system, industrial water effluent containing methylmercury compounds had not been discharged outside of the plant since 1966, and the pollution source itself was eliminated through cessation of the production of acetaldehyde in 1968. In the Agano River basin area, the production of acetaldehyde was discontinued before the discovery of Minamata disease. As a result, the wide-ranging environmental protection policies and measures that we have today come to be developed.