We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Characterizing microplastics in urban runoff: A multi-land use assessment with a focus on 1–125 μm size particles
Summary
Researchers collected stormwater runoff from three different urban land use types and found microplastics present across all sites, with significant variation in polymer types depending on the area. By using multiple detection techniques, they were able to identify particles as small as 1 micrometer, revealing that the smallest size fractions dominated the total count. The study emphasizes that urban runoff is a major pathway for microplastic pollution reaching waterways.
Urban areas play a significant role in generating microplastics (MPs) through increased vehicular and human activities, making urban runoff a key source of MP pollution in receiving waterways. The composition of MPs is anticipated to vary with land use; hence, identifying the hotspots of contamination within urban areas is imperative for the targeted interventions to reduce MPs at their sources. This study collected one-liter stormwater runoffs from three different land uses as sheet flow during two storm events to quantify the MPs and identify the polymers transported from land-based sources. The analytical method included a combination of Fourier transform infrared spectrometer, Raman microscope, and Nile red staining techniques. This study analyzed the broad spectrum of MPs, i.e., 1 μm-5 mm, and tire wear and bitumen particles, considered the two major research gaps in stormwater studies. The MP concentrations were 67.7 ± 11.3 pLin commercial, 23 ± 10.3 pL in residential, and 168.7 ± 37.1 pLin highways. The trend of MP concentrations followed an order of highway > commercial > residential with an exclusive presence of polymethylmethacrylate and ethylene-vinyl acetate in highways; cellophane, methylcellulose, polystyrene, polyamide, and polytetrafluorethylene in commercial; and high-density polyethylene in residential areas. The dominant MP morphology consisted of fragments, accounting for 89 % of the identified MPs, followed by 10 % fibers and 1 % films. This study observed a prevalence of MPs sizes <125 μm constituting 49 % of the total composition. These findings underscore the vital role of land use patterns in shaping MP abundance and reinforce the urgency of implementing effective management strategies to mitigate MP pollution in stormwater runoff.