The Environment Ministry is considering banning the dumping at sea of waste such as sewage sludge in a bid to curb marine pollution.
The move is a step toward ratifying a protocol of the 1972 Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter. The international treaty on regulating sea dumping is also known as the London Convention.
The ministry said it will submit revisions to related legislation, including the Marine Pollution Prevention Law, at the regular Diet session next year at the earliest.