A recent study from Yale University's Department of the Environment indicates that if cities and businesses invest in appropriate treatment systems, switching to biodegradable plastics could reduce toxic pollution by more than a third and significantly decrease global plastic waste accumulation by mid-century.
The study, titled "The role of biodegradable plastics in the global plastic future," was published on January 16 in *Nature Reviews Clean Technology*. This is the first study to systematically predict the environmental impact of biodegradable plastics throughout their entire life cycle on a global scale. The assessment covers raw material acquisition, production, use, and various end-of-life scenarios-including their entry into the environment and formation of microplastics.
The study found that by 2050, replacing traditional plastics with biodegradable plastics as much as possible could reduce ecotoxicity by up to 34% with almost no impact on energy demand. Combined with ideal waste management of traditional plastics, global waste accumulation could be reduced by up to 65%. However, realizing these benefits requires proper disposal of these materials, such as through industrial composting and anaerobic digestion.
"Biodegradable plastics do help reduce the accumulation and ecotoxicity of plastic waste, but these advantages may not be realized if end-of-life treatment is inadequate," said Yuan Yao, associate professor of industrial ecology and sustainable systems at Yale University and corresponding author of the study. "We need more infrastructure for biodegradable plastics disposal, as well as increased public education on use and sorting.
This research builds on a 2024 study by Yuan Yao and his team. Previously, they developed a method to assess the environmental impact of biodegradable microplastics in water bodies and discovered a key trade-off: faster degradation rates result in lower ecotoxicity, but also higher greenhouse gas emissions.
Their earlier method also predicted the impact of plastic production across multiple sustainability dimensions. In this new study, they used this method to analyze the proportion of conventional plastics that can be technically replaced, different waste management scenarios, the growth of global plastic use, and regional climate differences such as temperature.
Researchers say these findings highlight the need to fully realize the benefits of the rapidly growing biodegradable plastics market, including increased research into water-saving raw materials and investment in expanding waste management infrastructure-from anaerobic digesters for biodegradable plastics to recycling and processing facilities for conventional plastics.
They also point to the need for a standardized labeling system to avoid consumer confusion and ensure plastics are correctly classified and disposed of. "Biodegradable plastics are not a single type of product," says Yuan Yao. "It's a huge category encompassing many different types of plastics, so an important question is how we label these different materials and educate consumers about the differences between them." The researchers also emphasize that biodegradable plastics are only one part of the solution.
First author Zhengyin Piao notes, "Conventional plastics will still dominate the future plastics market, and we cannot effectively reduce waste accumulation if we don't address the problems with conventional plastics. However, if we adopt a comprehensive strategy-simultaneously reducing the amount of conventional plastics going to landfills and increasing the use of biodegradable plastics-we can curb the trend of future waste accumulation."
