Atmospheric microplastics: Challenges in site- and target-specific measurements

Atmospheric microplastics (MPs) are a significant environmental concern, necessitating tailored analytical methods for specific sites like residential, public, and outdoor environments. This review addresses site- and target-specific challenges in sampling, pretreatment, and quantification of atmospheric MPs. Sampling methods include wet and dry deposition, sweeping, and active sampling, with classification based on locations. Circular diagrams classify MP types and shapes commonly found in different areas, aiding identification of key MPs based on locations. Indoors, PET fibers are common, while outdoors, PE fragments are additionally detected due to long-range air transport, necessitating tailored approaches. Pretreatments like sieving, digestion, density separation, staining are introduced, with customized approaches for each target MP. Furthermore, four MP standards (PET, PE, PP, and PS) are analyzed using advanced techniques, offering distinct analyses for each MP type. These integrated approaches aim to provide guidance on selective analytical methods, ensuring accurate atmospheric MP measurement for each site and target.