Plastic consumption among the Group of 20 major economies in 2050 will be 1.7-fold higher than 2019 levels without new measures to reduce use, increasing the problem of marine plastic pollution, a study showed Monday.

Economist Impact and Nippon Foundation estimate in their joint research that plastic usage could reach 451 million tons in 2050, up from 261 million tons in 2019, without further steps.

Even if progress is made in addressing the issue, such as through more countries imposing bans on some plastic products or taxation measures, consumption is estimated to reach 325 million tons, according to the research.

File photo taken in November 2021 shows plastic waste washed up on Ishigaki Island, Okinawa Prefecture. (Kyodo)

The research team warned that without tougher measures under international treaties on usage currently being negotiated, marine contamination by plastic waste cannot be stopped.

In March 2022, 175 countries signed a resolution to end plastic pollution at the U.N. Environment Assembly. Specific measures are yet to be decided, and an intergovernmental negotiating committee aims to complete a draft legally binding agreement by the end of 2024.

The United Nations has said that around 11 million tons of plastic waste flows into oceans annually, with the number projected to potentially triple by 2040. Plastics also put over 800 marine and coastal species at risk through such dangers as ingestion and entanglement.

The G-20 has stepped up efforts to reduce marine plastic pollution. In 2019, the group agreed to create an international framework to promote voluntary steps to address the issue.

The G-20 groups Argentina, Australia, Brazil, Britain, Canada, China, France, Germany, India, Indonesia, Italy, Japan, Mexico, Russia, Saudi Arabia, South Africa, South Korea, Turkey, the United States and the European Union.

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