Integrated Sample Preparation and TGA-FTIR/μ-FTIR Characterization for the Simultaneous Analysis of Airborne Microplastics and Organic Compounds in Atmospheric Particulate Matter

The growing concern regarding airborne microplastics (MPs) and their potential health effects has highlighted the need for analytical approaches capable of addressing the complexity of atmospheric particulate matter (PM) [1–3]. The coexistence of polymer particles with organic and inorganic components makes MP isolation and contaminant characterization particularly challenging. In this work, for the first time, an integrated analytical workflow was developed for the simultaneous investigation of airborne microplastics and organic compounds in PM samples collected in an industrial packaging facility processing polyethylene granules. Dichloromethane (DCM) was employed as a selective extraction solvent to remove interferences and recover organic compounds while preserving polymer composition and particle size, thus enabling sequential characterization of both fractions from the same PM sample. The extracted organic fraction was characterized by GC-MS, enabling the identification of additives and other organic constituents. Following extraction, the particulate fraction underwent density separation and purification to isolate microplastics. The isolated microplastics were characterized by μ-FTIR ATR to determine morphology, size distribution, and polymer composition. In parallel, a TGA-FTIR method was optimized using reference polymers (PE, PET, PP, PS, and PVC) and applied to pretreated PM samples for the semi-quantitative determination of polymeric content. The combined approach identified PE as the predominant polymer in deposited dust and airborne PM fractions, particularly in coarser particles, while simultaneously providing information on the associated organic fraction. To the best of our knowledge, the proposed workflow represents the first integrated analytical strategy enabling simultaneous characterization of airborne microplastics and PM-associated organic contaminants from the same PM sample through a single sample preparation procedure, providing a comprehensive analytical tool for environmental and occupational exposure assessment.

[1] Zhang X, et al., Front Public Health. 2025;13:1567200.

[2] Gomiero A, Skogerbø G. Int J Hyg Environ Health. 2026;114789.

[3] Prata JC. Environ Pollut. 2018;234:115–126.