Microplastic removal across ten drinking water treatment facilities and distribution systems

Area of Science:

• Environmental Science
• Water Treatment Technology
• Materials Science

Background:

• Microplastic contamination in drinking water is a growing concern.
• Standardized methods for microplastic analysis are lacking, hindering comparative studies.
• Understanding microplastic removal in water treatment is crucial for public health.

Purpose of the Study:

• To quantify microplastic removal efficiency in municipal drinking water treatment facilities.
• To characterize microplastic concentrations and types in source waters and distribution systems.
• To evaluate the effectiveness of different treatment processes in microplastic removal.

Main Methods:

• Sampling of source water, treated water, and distribution system water from ten drinking water treatment facilities.
• Isolation and characterization of microplastics (>2 µm) using standardized analytical techniques.
• Identification of polymer types using spectroscopy.

Main Results:

• Drinking water treatment facilities achieved over 97.5% microplastic removal.
• Chemically assisted granular media filtration and ultrafiltration were key removal processes.
• Untreated source waters showed high microplastic concentrations (1193–7185 particles/L).
• Polypropylene, polyethylene, polyamide, and plastic copolymers were the most prevalent microplastic types.

Conclusions:

• Municipal drinking water treatment is effective in removing a significant majority of microplastics.
• Source water quality significantly impacts microplastic levels in drinking water.
• Findings can inform regulatory development and improve microplastic removal strategies.