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
By Yang Liu, WeiJian Liu, YunSong Xu, YongZhi Zhao, Pei Wang, ShuangYu Yu, JiaoDi Zhang, Yi Tang, GuanNan Xiong, Shu Tao, and WenXin Liu
Sci. of Total Env.
August 20, 2019
Atmospheric PM10 (particulate matter with aerodynamic diameter <10 μm) samples were collected in the cities along the Bohai Sea Rim during heating and non-heating periods, and ionic per- and polyfluoroalkyl species (PFASs) in the PM10 were measured. The total concentration of ionic PFASs ranged from 21.8 to 87.0 pg/m3, and the mean concentration of ionic PFASs during the day (42.6 pg/m3) was slightly higher than that at night (35.1 pg/m3). Generally, diurnal variations in the levels of ionic PFASs were consistent with those in the PM10 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 < 0.05) between the main components of PFASs and O3 implied that oxidative degradation (O3 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 PM10 exhibited an insignificant contribution to the estimated average daily intakes (ADIs) of PFASs by different age groups. In addition, the calculated hazard ratios (HRs) 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.
• Heating activity and diurnal variation affected the levels of PFASs in PM10.
• PFOA, PFPeA and PFBA were determined to be the dominant species.
• Backward trajectory indicated fluorine chemical plant as a main source of PFASs.
• No strong health risks by inhalation exposure to PFOA and PFOS were estimated.