Research on microplastics to date has focused primarily on marine systems. However, the main sources of microplastics in these systems are land-based. These sources primarily include landfill refuse, biosolids from wastewater treatment process, and food waste. Plastics in the environment may contain additives and chemical by-products that negatively affect the environment. Understanding how these tiny (>5 mm) particles form and are transported will inform future microplastics-related laws and regulations.
The goals of this study were to:
- quantify the amount of microplastics present in each stage of landfill leachate treatment,
- verify if the wastewater treatment process degrades the plastics, and
- verify whether microplastics are released to the environment after treatment.
ISTC researchers collected leachate samples from different locations (directly from the landfill, after transportation to a wastewater treatment plant, and after mixing with municipal wastewater) to quantify the amount of microplastics at each stage. Preliminary results on the size distributions of microplastics detected in one system show that the wastewater treatment process breaks microplastics down into smaller sizes. As the study continues, the researchers expect to see 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.