Microplastic Pollution in Surface Water: Identification of Contamination Sources and Evaluation of Low-Cost Filtration as a Mitigation Strategy

Abstract

Microplastic pollution is now recorded in rivers, lakes, estuaries, and treated wastewater. Surface water is important because it connects land-based sources with drinking-water intakes, aquatic life, and coastal seas. This paper identifies common contamination sources and evaluates low-cost filtration as a practical mitigation route. The study uses a secondary data design based on public monitoring studies and published filtration experiments. Monitoring evidence was drawn from the River Thames, Mississippi River, Pearl River, Yangtze River Basin, and wastewater treatment studies. Source evidence was assessed using reported particle shape, polymer type, land use, and transport pathway. The synthesis shows that fibers, fragments, films, rubber-like particles, and pellets point to different sources. Likely sources include synthetic textiles, tyre wear, packaging waste, urban dust, wastewater effluent, and stormwater runoff. Reported surface-water abundance varied widely, from below one particle per liter to many particles per liter. This spread reflects true local pressure and different sampling methods. Filtration evidence shows that sand filtration, biochar, membrane bioreactors, and chitin-cellulose foam can remove high particle shares. Reported removal often exceeded 90 percent under tested conditions. Low-cost treatment is strongest when coarse screening, settling, sand filtration, and biochar are combined. The paper proposes a source-to-filter management framework for urban surface water. It also stresses quality control, safe handling of spent filter media, and source reduction. Filtration can lower exposure, but it cannot replace plastic prevention at source.