Landfills as a Major Point Source for Microplastic Pollution
Research on microplastics to date has focused primarily on marine systems. The main source of microplastics into these systems though, are land-based. These sources primarily include landfill refuse, biosolids from wastewater treatment process, and food waste. Plastics in the environment may have within them additives and chemical by-products that have negative impacts on the environment. Understanding how these tiny (>5mm) particles are formed and transported will inform microplastics related laws and regulations in the future.
The goals of this study were to (1) quantify the amount of microplastics present in each stage of landfill leachate treatment, (2) verify if the wastewater treatment process degrades the plastics, and (3) verify if microplastics are released to the environment after treatment. ISTC researchers collected samples of leachate from different locations (directly from the landfill, after transportation to a wastewater treatment plant, and after the leachate was mixed with municipal wastewater) to quantify the amount of microplastics present in each stage. Preliminary results of the size distributions of the microplastics detected in one of the systems shows that the wastewater treatment process does break the microplastic down to smaller sizes. As the study continues, the researchers expect to continue to observe these trends in other systems.
Funding for this project comes from the Hazardous Waste Research Fund which is overseen by ISTC. More results are expected in summer 2023.