A Review of the Sampling, Analysis, and Identification Techniques of Microplastics in the Air: Insights into PM2.5 and PM10

The massive use of plastics has raised growing environmental concerns, including microplastic (MP) pollution. While most studies have focused on MPs in aquatic environments, research on airborne microplastics has gained increasing attention in recent years. This review discusses the sampling, analytical, and identification techniques used for MPs, with a particular focus on PM2.5 and PM10 fractions, which have been scarcely addressed in the literature. The main active and passive sampling methods, sample preparation protocols, MP quantification approaches, and chemical characterization techniques applied to airborne plastic particles are compiled. Attention is given to the influence of meteorological conditions on transport and deposition, as well as to the predominant sources of primary and secondary microplastics in both indoor and outdoor environments. The analysis identifies the main research challenges, particularly in the detection of microplastics and in the standardization of protocols. The review highlights the need for standardized methodologies to advance reliable quantification and to better understand the environmental implications of MPs.