Analysis of airborne microplastics using μ-raman spectroscopy in Seoul

Airborne microplastics (AMPs), known to be persistent pollutants, have recently been detected in the atmosphere and even in human lung tissue, raising concerns about potential human respiratory exposure. In light of these concerns, this study aimed to investigate the distribution and composition of AMPs in Seoul. μ-Raman spectroscopy was employed to identify fine particles (≥5 μm) and to contribute to the development of standardized monitoring protocols. Monthly air sampling was conducted from September 2023 to March 2024 at an urban rooftop site using a PM 10 air sampler. Samples were pretreated with hydrogen peroxide to remove organic matter, then filtered through a silicon filter. μ-Raman spectroscopy was applied for qualitative and quantitative analysis of microplastics. The mean concentration of AMPs was 74.0 ± 29.9 particles/m 3 , with polyethylene (46.7%) and polystyrene (21.8%) being the most prevalent polymer types. Most particles (64.5%) were in the size range of 5–10 μm, and fragment type particles accounted for 98.9% of the total. These results indicate that respirable microplastics are commonly present in urban air and that polymer composition may reflect both material properties and usage patterns. This research provides baseline data for future exposure and risk assessments and supports the need for international standardization of airborne microplastic analysis protocols.