Lab-Aged Microplastics Reveal How Aging Affects Contaminant Interactions

A new study is shedding light on how microplastics—tiny plastic particles under 5 millimeters—behave as they age in the environment, and whether they bind to contaminants. Researchers artificially aged three common polymer types: polyethylene, polyethylene terephthalate, and polypropylene. By simulating environmental aging in the lab, they observed changes in the plastics' surface properties and their ability to sorb (stick to) surrounding pollutants. This matters because microplastics are ubiquitous in waterways, soils, and even food chains, and their role as carriers of toxic chemicals could amplify exposure risks for wildlife and humans. The findings help clarify how plastic type and weathering conditions influence contaminant transport, a critical gap in risk assessments. As plastic pollution persists for decades, understanding these interactions is key to predicting long-term environmental and health impacts. The study provides a controlled baseline for future field research and regulatory science on microplastic pollution.