A study by Yale School of the Environment shows that if cities and enterprises invest in building appropriate waste treatment systems, switching to biodegradable plastics could reduce toxic pollution by more than one-third by the middle of this century and significantly lower the global waste volume; however, without proper composting facilities, biodegradable plastics might double greenhouse gas emissions.
This study was published in the journal "Nature Reviews: Clean Technology" on January 16, 2026. It is the first research to predict the environmental impact of biodegradable plastics throughout their entire life cycle on a global scale. The research scope covers the entire process from raw material acquisition to various end-processing methods, including the situation where they eventually enter the natural environment in the form of microplastics.
The research results show that by replacing traditional plastics with biodegradable plastics as much as possible, the ecological toxicity can be reduced by up to 34% by 2050, with almost no impact on energy demand; if combined with an ideal waste management system for traditional plastics, the global accumulation of waste can be reduced by as much as 65%.
However, to achieve these benefits, these materials need to be properly processed at the end stage through methods such as industrial composting and anaerobic digestion. If the alternative biodegradable plastics are ultimately landfilled, it could double the greenhouse gas emissions. Researchers have also found that the production of biobased degradable plastics would increase the water footprint of the industry by more than double compared to the current level, mainly because the cultivation of biomass raw materials requires a large amount of water.
The picture shows Yuan Yuan, an associate professor at the School of Environment at Yale University. Professor Yao Yuan graduated from Northeastern University with a bachelor's degree in Metallurgical Engineering (China) and from Northwestern University with a doctorate in Chemical Engineering (USA). She is currently an associate professor at Yale University. Her research aims to address the growing demand for sustainable solutions that can support industrial development without harming the environment or depleting resources for future generations. Her current research projects focus on the bioeconomy and sustainable production. Dr. Yao has received the National Science Foundation Early Career Development Award for Teachers (CAREER) in the United States. She was also selected by the American Institute of Chemical Engineers as one of the "35 Under 35 New Leaders in Chemical Engineering". https://environment.yale.edu/directory/faculty/yuan-yao
The senior author of this study, Yuan Yao, an associate professor of industrial ecology and sustainable systems, said: "Biodegradable plastics do help reduce the accumulation of plastic waste and ecological toxicity. However, if the final processing环节 is not managed properly, these benefits cannot be achieved. We need to build more infrastructure to standardize the processing of biodegradable plastics, and at the same time, we need to carry out public education to enable people to master the correct usage methods
This research was conducted based on the study by Yao Yuan and postdoctoral researcher Zhengyin Piao in 2024. In their 2024 study, the two developed a method to assess the environmental impact of biodegradable microplastics in water bodies. At that time, a trade-off relationship was discovered: the faster the degradation rate of biodegradable plastics, the lower their ecological toxicity, but they would produce more greenhouse gases.
The method they developed in their earlier research can also predict the impact of plastic production on multiple dimensions of sustainable development. In this new study, the research team used this method to analyze the proportion of traditional plastics that can be replaced at the technical level, different waste management scenarios, the growth trend of global plastic usage, and the differences in regional environmental conditions such as temperature.
The researchers pointed out that the results of this study highlight the necessity of fully exploiting the benefits of the rapidly developing biodegradable plastic market. This includes increasing investment in the research and development of water-saving raw materials, as well as expanding waste management infrastructure - including both anaerobic digestion units for processing biodegradable plastics and facilities for recycling and treating traditional plastics. They also noted that a standardized identification system needs to be established to avoid confusion among consumers and ensure that plastics are correctly classified and handled.
Yao Yuan said, "Biodegradable plastics are not a single category; rather, they form a vast category that includes various types of plastics. Therefore, a key issue is how we should label these different materials and educate consumers about the differences between them."
The authors of the study also emphasized that biodegradable plastics are only one part of the solutions to the plastic problem.
The first author of the study, Park Jung-eun, said: "The future plastic market will still be dominated by traditional plastics. If we fail to solve the problems brought about by traditional plastics, we will not be able to effectively reduce the accumulation of waste. However, if we adopt a combined strategy - reducing the landfill volume of traditional plastics and increasing the use of biodegradable plastics - we can curb the growth trend of future waste accumulation."
