title: Neutral and ionic per- and polyfluoroalkyl substances (PFASs) in atmospheric and dry deposition samples over a source region (Tianjin, China).
abstract: Per- and polyfluoroalkyl substances (PFASs) were detected in the atmosphere of a source region in Tianjin, China. Fluorotelomer alcohols (FTOHs) were the dominant neutral PFASs in the atmosphere with total concentrations of 93.6-131 pg/m(3) and 8:2 FTOH contributing the most, whereas perfluorooctane sulfonamide derivatives (PFOSAs) were two magnitudes lower or undetected. In comparison, ionic PFASs (perfluoroalkyl carboxyl acids (PFCAs)) in the atmosphere were detected at similar or even higher levels. At wastewater treatment plants (WWTPs), the air over influent was found with higher levels of FTOHs than over aeration tank and effluent; whereas in the air over the aeration tank, the concentrations of PFOSAs and nonvolatile ionic PFASs substantially increased, suggesting a possible direct release of ionic PFASs to the atmosphere besides the atmospheric conversion from volatile precursors. In the air phase, a low proportion (1-5%) of PFCAs was subjected to dry deposition in the source region. Interestingly, the dry-deposition-to-bulk-air ratios of PFCA analogues were the lowest at medium chain lengths (C8 and C9) and increased with either shorter or longer chain length. The extraordinary affinity of shorter-chain PFCAs (C6-C7) to particles was presumed to be due to their smaller molecular size favoring the interactions between the carboxyl head groups and specific sorption sites on particulate matter.
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Yiming
authors.initials: Y
authors.lastname: Yao
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Chang
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address: sunhongwen@nankai.edu.cn.
authors.forename: Hongwen
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Environmental Science and Engineering, Sichuan University, Chengdu, Sichuan, 610065, China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Gan
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Hu
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
authors.forename: Yufen
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002681:China; D005466:Fluorocarbons / Q000032:analysis*; D007477:Ions; D009930:Organic Chemicals; D052638:Particulate Matter / Q000032:analysis
chemical_list: D000393:Air Pollutants; D005466:Fluorocarbons; D007477:Ions; D009930:Organic Chemicals; D052638:Particulate Matter; C073608:perfluorooctane
keywords: Atmosphere; Dry deposition; Long range transport; Per- and polyfluoroalkyl substances; Wastewater treatment plant