Wet Deposition of Globally Transportable Microplastics (<25 μm) Hovering over the Megacity of Beijing

• DOI: 10.1021/acs.est.3c03474
• Publication Date: 2023-07-17T15:23:27Z
• Authors: Yalan Chen; Jinqiong Niu; Dongyu Xu; Mengyu Zhang; Ke Sun; Bo Gao
• Keywords: Deposition; Megacity

Microplastics of size <25 μm possess globally transportable features, but the impact precipitation on their transport remains unclear. Here, microplastics were detected in all 10 studied rainfalls Beijing, with present 8 rainfalls. Interestingly, microplastic abundance (7590-136,778 items·m-3) was tentatively linked to maximum rainfall intensity, making up 39.6 (±27.5)% total count. The composition differed from that larger microplastics, although both mainly comprised polystyrene, polyethylene, and polypropylene. communities among rainfalls, suggesting atmospheric is a highly dynamic process. first exhibited highest community diversity after long-term exposure dry environment. deposited unstable fragmented according conditional fragmentation model. wet deposition rate calculated as 2-463 μg·m-2 (146-8629 items·m-2) per rain, amounting 25.44 tons annum Beijing. Although represented negligible proportion (0.00-1.24%) overall mass load numerical high. Our results demonstrate an effective mechanism for removing airborne which may enter urban soils waters, exacerbate burdens environment, cause potential risk human health.