Kyushu University researchers published a report in the Marine Pollution Bulletin that for the first time set clear numerical targets for solving the global problem of marine plastic pollution. By mapping the movement of plastic waste and its impact on the ocean, the team determined that plastic waste must be reduced by at least 32% by 2035 to avoid further harm to the marine environment.
Marine plastic pollution is a growing problem around the world, and unless significant intervention is taken, it will only get worse. Professor Atsuhiko Isobe of Kyushu University's Institute of Applied Mechanics has been monitoring and tracking plastic pollution in the ocean for several years. In 2022, his research team reported that an estimated 25.3 million metric tons of plastic waste entered the ocean, nearly two-thirds of which could not be monitored.
"My research focuses on tracking where plastic waste goes after it is discharged into water sources such as rivers and oceans. We use computer models to track how plastic moves and breaks down over time," explains Chisa Higuchi, the study's first author and a postdoctoral researcher in Isobe's lab.
Plastic waste persists for a long time, but larger plastics gradually break down into smaller plastic particles. While larger plastics are easier to remove, when they become smaller than 5 millimeters, they are classified as microplastics, making them harder to collect and easier for fish to eat them. So even if littering stopped today, the amount of microplastics would continue to increase.
At the 2019 G20 Osaka Summit, participants proposed the "Osaka Blue Ocean Vision", which aims to prevent the increase of marine plastic pollution by 2050. The initiative aims to improve global waste management strategies through international cooperation.
"We wanted to figure out the ideal scenario for Osaka's blue ocean vision to be successful," Higuchi explained. "So we used computational modeling and fieldwork to understand where and how plastic flows into the ocean. The maps we created are similar to weather forecast maps, but instead of showing when and where it will rain, these maps show different scenarios of when and where plastic will end up in the ocean."
Researchers studied the time it takes for different types of plastic to break down into smaller particles. In addition, they collected data on plastic discharge routes from rivers and other sources leading to the ocean.
According to the trajectory they mapped, plastic waste entering the ocean will be reduced by 32% by 2035, equivalent to 8.1 million tons, and by 2050, plastic in the ocean will eventually be reduced by more than 50%. In heavily polluted sea areas such as the Yellow Sea and East China Sea, the effect is even more obvious. According to the research team's assumptions, plastic waste here can be reduced by up to 63%.
"This not only provides concrete targets for the Osaka Blue Ocean Vision, but also provides measurable targets for governments and businesses," Higuchi said. "Of course, we need to do more than just clean up existing pollution, we must also reduce new plastic waste entering the ocean and rivers. If we adopt waste improvement measures With strategies like management, promoting reusable alternatives to single-use plastics, and raising public awareness, many people may feel pessimistic when they hear about the ongoing plastic waste problem in our lives, but I remain optimistic that we can find a way out of it."
Compiled from /ScitechDaily