Driven by the availability of cheap shale gas, the petrochemical industry is rapidly ramping up its production of plastic. But even with aggressive policies to control plastic trash, this could mean up to 53 million metric tons (t) of plastic will enter the world’s rivers, lakes, and oceans each year by 2030, researchers report (Science 2020, DOI: 10.1126/science.aba3656).
That’s more than twice as much as the estimated 19 million–23 million t of plastic waste that entered aquatic ecosystems in 2016, says a team of 20 researchers from Asia, Australasia, Europe, and North America.
In the study, led by Stephanie B. Borrelle, a postdoc at the University of Toronto who works on conservation ecology, researchers used computer models to study current strategies to keep plastic from entering waterways and to determine how much plastic rubbish ends up in rivers, lakes, and oceans. They found that growth in plastic pollution will continue outpacing even aggressive control efforts during the next decade.
To make meaningful cuts in the amount of plastic getting into rivers, lakes, and oceans will require one of two actions, the researchers conclude. One is halting growth in plastic production and use. The other is transforming production, use, and disposal of plastic into a circular economy that values end-of-life items as raw material rather than waste for disposal, the paper says.
This latter strategy would pose challenges for chemists, engineers, policymakers, and plastic manufacturers. These challenges include “reducing or eliminating the use of unnecessary plastics, setting global limits for virgin plastic production, creating globally aligned standards for commodity plastics to be practically recoverable and recyclable by design, and developing and scaling plastic processing and recycling technologies,” Borrelle’s team says.
“Achieving substantial reductions in global plastic emissions to the environment requires an urgent transformative change,” the researchers conclude. The American Chemistry Council (ACC), which represents manufacturers of plastic resins, says plastics don't belong in the environment and that the plastics industry is committed to solving this problem.
"However, recommendations to reduce plastics production and use would be highly counterproductive and impractical," the ACC says in a statement. "Studies show that alternatives to plastics can significantly increase our environmental footprint."
This article was updated Sept. 22, 2020, to add comments from the American Chemistry Council.