Microplastic removal across ten drinking water treatment facilities and distribution systems

The performance of conventional and advanced drinking water treatment processes for the removal of microplastics is poorly understood due to the use of a wide range of methods for sample collection, isolation, and analysis that make direct comparison among studies challenging. In this study, microplastic (>2 µm) removal across ten drinking water treatment facilities, as well as their presence in source waters and distribution systems, was characterized. Municipal drinking water treatment facilities achieved >97.5% removal, primarily due to chemically assisted granular media filtration or ultrafiltration. In untreated source waters, concentrations ranged from 1193 ± 64 to 7185 ± 64 particles/L, with polypropylene, polyethylene, polyamide, and plastic copolymers representing the most common polymer types identified. These findings provide insight regarding microplastic exposure via drinking water, as well as treatment process performance for their removal which may be used to inform the development and implementation of future regulations and/or guidelines.