Water Resources Research Act Program

Details for Project ID RI-2025_Andreu

The role of particle-particle collisions and shear forces on microplastic fragmentation in freshwater systems

Institute: Rhode Island
Year Established: 2025 Start Date: 2026-01-01 End Date: 2026-12-31
Total Federal Funds: $20,000 Total Non-Federal Funds: $20,257

Principal Investigators: Irene Andreu

Project Summary: Microplastics are small pieces of plastic that are now common in rivers, lakes, and oceans. Their size and shape influence how they move through water and what effects they may have on the environment. Over time, microplastics can break into even smaller pieces, but we still don't fully understand how this happens. This project will study how the movement of water and collisions between particles cause microplastics of different shapes to fragment. We will test this in controlled experiments by stirring microplastics in water for several weeks and tracking how they change. Microscopes will be used to see whether the particles become smaller, take on new shapes, or form even tinier fragments called nanoplastics. We will also look at whether weathering (exposure to natural conditions) makes them more likely to break apart.The results will provide new insight into how microplastics transform and spread, helping us better predict their impact on freshwater systems, including rivers in Rhode Island.