Occurrence and transport behaviors of perfluoroalkyl acids in drinking water distribution systems

Ruya Chen; Guiwei Li; Ying Yu; Xu Ma; Yuan Zhuang; Hui Tao; Baoyou Shi

doi:10.1016/j.scitotenv.2019.134162

Occurrence and transport behaviors of perfluoroalkyl acids in drinking water distribution systems

Sci Total Environ. 2019 Dec 20:697:134162. doi: 10.1016/j.scitotenv.2019.134162. Epub 2019 Aug 28.

Authors

Ruya Chen¹, Guiwei Li¹, Ying Yu¹, Xu Ma², Yuan Zhuang³, Hui Tao⁴, Baoyou Shi⁵

Affiliations

¹ Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² School of Environment & Natural Resource, Renmin University of China, Beijing 100872, China.
³ Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
⁴ College of Environmental Science and Engineering, Hohai University, Nanjing 210098, China.
⁵ Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: byshi@rcees.ac.cn.

PMID: 31491637
DOI: 10.1016/j.scitotenv.2019.134162

Abstract

Although human exposure to perfluoroalkyl acids (PFAAs) through tap water is an ongoing concern, knowledge of the PFAAs occurrence in the tap water and the associated transport behaviors of PFAAs in drinking water distribution systems (DWDSs) are scarce. This investigation profiled the occurrence of 17 kinds of PFAAs in tap water of some Chinese cities, and the transport behaviors of PFAAs in DWDS were observed in eastern China. Tap water samples both along trunk pipelines and at the distal ends were collected to display the PFAAs occurrence scenarios. Loose deposit solids were also obtained to reveal their possible accumulation effect on PFAAs. The results showed that perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA) widely existed in tap water samples, and were the predominant PFAAs in eastern China areas. The mean concentration of the 17 PFAAs was 77.49 ng/L (ranging from 9.29 ng/L to 266.68 ng/L). Short-chain PFAAs (mainly PFBA) concentrations were relatively stable from water treatment plant to consumer taps, while long-chain PFAAs (mainly PFOA) exhibited a significant decrease in concentration, which could be attributed to their accumulation by the loose deposits in the DWDSs. It was calculated that PFOA has a higher partition coefficient than PFBA; this means that the former has a stronger potential to be adsorbed by loose deposits. In addition, the accumulation ability of loose deposits might be associated with the composition of Al, Fe and Si in the loose deposits. The positive correlation between the short-chain PFAAs and dissolved organic carbon (DOC) indicated the possible interactions between PFAA and natural organic matter could favor short-chain PFAAs to retain in bulk water. When water quality conditions change or hydraulic disturbance occur, loose deposits may enter tap water bringing accumulated PFAAs with it, which may result in potential health risks.

Keywords: Drinking water distribution systems; Loose deposits; Occurrence; Perfluoroalkyl acids; Transport behaviors.

MeSH terms

Alkanesulfonic Acids
Caprylates / analysis*
Drinking Water / chemistry*
Environmental Monitoring*
Fluorocarbons / analysis*
Water Pollutants, Chemical / analysis*
Water Purification

Substances

Alkanesulfonic Acids
Caprylates
Drinking Water
Fluorocarbons
Water Pollutants, Chemical
perfluorobutyric acid
perfluorooctanoic acid