Concentration of Microplastics in Road Dust as a Function of the Drying Periods

Microplastics (MPs) are plastic particles < 5 mm in diameter, which are detected in air, soil, and water, causing various environmental problems. in total, 37.3% of mps are generated from point pollution sources and 62.7% from non-point sources; most of the non-point-source mps are from vehicles tires, road-marking paint, and bitumen used in road pavements. in this study, the con-centrations of mps generated from roads in goyang city, south korea, were examined in terms of the drying period (0, 1, 2, or 3 d). road dust sampling was performed at the kerb and quantitative and qualitative analyses were conducted for each sample. the mp concentrations were 552 ( 39) mps g1 for a 0 d drying period and 1530 ( 602) mps g1 for a 3 d drying period, confirming that the mp concentration in road dust increased with the increase in drying period. among the detected substances, black particles accounted for the highest proportion (72%) and were found to be bi-tumen and tyre particles. this study also confirmed that the mps accumulated on roads were washed away when rainfall exceeded a certain amount.