Characteristics and human inhalation exposure of ionic per- and polyfluoroalkyl substances (PFASs) in PM10 of cities around the Bohai Sea: Diurnal variation and effects of heating activity

Abstract Atmospheric PM 10 (particulate matter with aerodynamic diameter per - and polyfluoroalkyl species (PFASs) in the PM 10 were measured. The total concentration of ionic PFASs ranged from 21.8 to 87.0 pg/m 3 , and the mean concentration of ionic PFASs during the day (42.6 pg/m 3 ) was slightly higher than that at night (35.1 pg/m 3 ). Generally, diurnal variations in the levels of ionic PFASs were consistent with those in the PM 10 concentrations. Perfluorooctanoic acid (PFOA, 23.5–33.7%), perfluoropentanoic acid (PFPeA, 28.3–39.9%) and perfluorobutyric acid (PFBA, 17.1–20.1%) accounted for the dominant compositional contributions. Significant positive correlations ( p 3 implied that oxidative degradation (O 3 served as the main oxidant) in the period of non-heating may affect the short-chain PFASs. The clustering analysis of a 72-h backward trajectory indicated that cross-provincial transport contributed to ionic PFASs at the sampling sites. Compared with ingestion via daily diet, the inhalation of PM 10 exhibited an insignificant contribution to the estimated average daily intakes ( ADI s) of PFASs by different age groups. In addition, the calculated hazard ratios ( HR s) for the non-cancer respiratory risk, based on the air concentrations of PFOA and perfluorooctane sulfonate (PFOS), also manifested lower non-cancer risk through inhalation exposure. Capsule The effects of heating and non-heating activity and diurnal variation on the concentrations of PFASs, dominated by PFOA, PFPeA, and PFBA in PM 10 , were determined, and atmospheric trans-provincial input served as an important source.