Quantitation of Atmospheric Suspended Polystyrene Nanoplastics by Active Sampling Prior to Pyrolysis-Gas Chromatography-Mass Spectrometry

Plastic has been demonstrated torelease nanoplastics(NPs) intothe atmosphere under sunlight irradiation, posing a continuous healthrisk to the respiratory system. However, due to lack of reliable quantificationmethods, the occurrence and distribution of NPs in the atmosphereremain unclear. Polystyrene (PS) micro- and nanoplastics (MNPs) representa crucial component of atmospheric MNPs. In this study, we proposeda simple and robust method for determining the concentration of atmosphericPS NPs using pyrolysis-gas chromatography-mass spectrometry(Py-GC/MS). Following active sampling, the filter membrane is directlyground and introduced into the Py-GC/MS system to quantify PS NPs.The proposed method demonstrates excellent reproducibility and highsensitivity, with a detection limit as low as down to 15 pg/m(3) for PS NPs. By using this method, the occurrence of PS NPsin both indoor and outdoor atmospheres has been confirmed. Furthermore,the results showed that the abundance of outdoor PS NPs was significantlyhigher than that of indoor samples, and there was no significant differencein NP vertical distribution within a height of 28.6 m. This methodcan be applied for the routine monitoring of atmospheric PS NPs andfor evaluating their risk to human health. A robust method has been developed forquantifying suspendedPS nanoplastics, bridging the gap between the fate of nanoplasticsand the conventional methodologies used for measuring inorganic particles.