A Japanese government survey suggests that the amount of plastic waste held at waste disposal operators has been increasing at some cities since China banned imports in 2017.
The Environment Ministry in March surveyed industrial waste disposal companies and local governments across Japan which oversee those firms.
As for local governments, 122 prefectures and major cities all responded.
Twenty-four of them, or 19.7 percent, said plastic waste stored at disposal facilities increased between last July and February this year. Fifteen, or 12.3 percent, said there were companies that stored more than the limit set by the central government.
Japan used to export part of its plastic waste to China as a recyclable resource. But Beijing banned imports in December 2017 for environmental reasons. Some Southeast Asian countries have also restricted their acceptance of plastic waste.
Environment Ministry officials say they will consider promoting cooperation among local governments to better cope with plastic waste to prevent any illegal or inappropriate disposal.