[Pollution Characteristics and Source Apportionment of Typical and Emerging Per- and Polyfluoroalkylated Substances in Tuojiang River Basin].

Forty-eight surface water samples were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) in order to study the pollution characteristics and source apportionment of per- and polyfluoroalkylated substances (PFASs) in the Tuojiang River. The results showed that ΣPFASs in the Tuojiang River ranged from 12.5-3789 ng·L-1, and perfluorooctanoic acid (PFOA) was the predominant PFAS, with a concentration of 9.97-3764 ng·L-1 (73.6%-99.8%), suggesting that legacy PFASs were still the dominant PFASs in the Tuojiang River. The most frequently detected emerging PFASs was 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B), with a detection frequency of 100%, suggesting the wide use of F-53B in the Tuojiang River. Sodium 1H, 1H, 2H, 2H-perfluorooctane sulfonate (6:2 FTS) displayed the highest concentration among all emerging PFASs[nd-27.3 ng·L-1, mean:(9.12±7.70) ng·L-1], and the concentrations were at the higher levels compared to those in other rivers around the world. In addition, ΣPFASs showed the highest concentrations of ΣPFASs at the fluorochemical manufacturing park (FMP), followed by those in the Luzhou section (in the lower reaches of the Tuojiang River), indicating that the emission of FMP and human daily production activities were the main influencing factors of PFASs pollution in the Tuojiang River. The estimated flux of PFASs from the Tuojiang River to the Yangtze River was 353 kg·a-1, and PFOA displayed the greatest mass loading (348 kg·a-1), which could provide the basic data for controlling PFASs in the Tuojiang River.

[Distribution Characteristics and Source Apportionment of Perfluoroalkyl Substances in Surface Soils of the Northeast Tibetan Plateau].

Surface soil samples collected at 18 sites from the northeast Tibetan Plateau were used to analyze perfluoroalkyl substances (PFASs) via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to study the concentration levels and sources of PFASs. The results showed that 11 PFASs were detected in the soil, and the ω(Σ11PFASs) ranged from 0.043-1.573 ng·g-1 with an average concentration of 0.398 ng·g-1. PFBA displayed the highest concentration level with a mean content of 0.164 ng·g-1, whereas PFHxA was at the lowest level (0.005 ng·g-1). The concentrations of the other PFASs were similar to each other (0.011-0.057 ng·g-1). Generally, PFASs contents in the west and north were higher than that in the southeast, and the alpine condensation effect existed for PFBA. The principal component analysis showed that PFASs in surface soils in the northeast Tibetan Plateau region mainly originated from the atmospheric transport of PFASs and their precursors. Few areas were affected by direct emissions of point source pollution, and the main sources were the industrial production of metals/minerals and other human activities.

[Pollution Characteristics and Exposure Risk Assessment of Perfluoroalkyl Substances in Road Dust, Chengdu].

To study the pollution characteristics and exposure health risk of perfluoroalkyl substances (PFASs) in road dust, 12 PFASs were analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) in this study. PFAS concentrations in road dust ranged from 0.95 to 111 ng·g-1, with an average concentration of (25.6±37.2) ng·g-1, suggesting large spatial differences between PFASs in road dust. PFAS concentrations on the main roads were significantly higher than on minor roads, and the minor roads downtown displayed higher concentration levels than suburban minor roads. Perfluorobutanoic acid (PFBA) was the predominant compound in Section 1 of Jie-fang Road, Jin-niu-ba Road and Shui-nian-he Road, while perfluroroocantanoic acid (PFOA, 24.8%) and perfluorooctane sulfonate (PFOS, 24.1%) were the main PFASs on other roads, indicating different sources of PFASs in these areas. The total daily dose of PFASs in road dust for children and adults were 0.168 ng·(kg·d)-1 and 0.028 ng·(kg·d)-1, respectively, suggesting higher exposure risk for children than adults. Therefore, more attention should be paid to children's health risk assessment. Daily doses of PFOA and PFOS in road dust for Chengdu residents were lower than the maximum daily intakes recommended by the European Authority, indicating that there was no immediate health risk to local residents.