0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Sign in to save

Origins and ecological risk of atmospheric microplastics at a remote background site in Japan

The Science of The Total Environment 2025 1 citation ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count.
Yan Wang, Libo Xu, Pengchu Bai, Xuan Zhang, Lulu Zhang, Xingshun Qi, Min Hu, Min Hu, Yi Huang, Seiya Nagao, Ning Tang

Summary

Atmospheric microplastics collected at a high-altitude site were traced to both local and long-range transport origins, revealing the broad geographical spread of airborne plastic particles. The ecological risk assessment found potential impacts on vulnerable high-elevation ecosystems far from pollution sources.

Atmospheric microplastics (AMPs) deposition was monitored over a 10-month period (May 2022 - Feb. 2023) at the Kanazawa University Wajima Air Monitoring Station (KUWAMS), a remote background site in Wajima, Japan. AMPs deposition rates at KUWAMS ranged from 55 to 560 n/(m·d), with 75 % of particles smaller than 50 μm. Fragments (96.4 %), fibers (1.7 %), beads (1.6 %), and films (0.2 %) were identified with fragments being the most common. Most AMPs were composed of polyamide (22.3 %) and polyethylene terephthalate (35.9 %), likely from packaging and automotive materials. Estimated AMPs possible transportation time and backward trajectory modeling, showed that higher AMPs deposition rates and compositional differences during summer (Jul. - Sep. 2022) and winter monsoon periods (Dec. 2022 - Feb. 2023), were driven by air masses from mainland Japan and continental Asia, respectively. Total annual AMPs deposition in Wajima (426 km) was estimated to be 2.27 tons. Our preliminary potential ecological risk evaluation indicated that KUWAMS falls under Risk Level V, indicating an extreme ecological consequence and necessitating further investigation into AMPs pollution. This is the first study to demonstrate that background sites in East Asian monsoon region exhibited AMPs deposition and complexity. These findings highlight the necessity for increased attention to AMPs in background sites and provide a valuable reference for future research.

Share this paper