Micro(nano)plastics in Size-Segregated Atmospheric Particles in Eskişehir, Türkiye: Optimization of Sampling Parameters

Abstract Inhalable micro(nano)plastics (MNPs < 10 μm) are ubiquitous emerging environmental pollutants that can enter the human respiratory tract and adversely affect respiratory health. A standardized methodology for the characterization of airborne MNPs is required, but one has yet to be established. To this end, a high-volume sampler with a five-stage cascade impactor was used to collect suspended particles and characterize MNPs. Following preliminary sampling at 40 cfm over a 24-h period, a notable accumulation of particles in descending cut-off sizes and agglomerated forms was observed. Subsequently, the size-fractionated sampling parameters were evaluated, including flow rate (20 and 40 cfm) and sampling duration (4, 8, 12, and 24 h), as the detection by spectrometric analysis was not feasible. The optimal sampling parameters were determined to be 40 cfm over eight hours through µ-Raman analysis. The MNPs were observed to comprise fragments and fibers, with a concentration of 434 MP/m 3 in stage 1, 431 MP/m 3 in stage 2, 1631 MP/m 3 in stage 3, 1117 MP/m 3 in stage 4, and 355 MP/m 3 in stage 5. The results of the spectrometric analysis indicated that over 90% of the MPs were carbon black, with the rest being polytetrafluoroethylene and polypropylene. This suggests that the majority of inhalable MPs were derived from tire and road wear. It is recommended that future studies examine the correlation between the concentration of suspended particles, the duration of sampling, and the amount of airborne MPs. Graphical Abstract