Field study on the transportation characteristics of PFASs from water source to tap water

Perfluoroalkyl substances (PFASs) can occur in water sources, pass through drinking water treatment plants (DWTPs), drinking water distribution systems (DWDSs), to the consumer taps. This investigation was carried out to present the transportation behaviors of 17 PFASs, involving seven DWTPs with different water sources, raw water transportation modes, treatment processes, and DWDS structures in eastern and northern China. The results showed that the long-distance raw water transportation pipelines removed a certain extent of PFASs from raw water, probably due to the accumulation of loose deposits. The long-distance, open-channel South-to-North water diversion increased PFAS contamination risk. In the DWTPs, granular activated carbon (GAC) adsorption and ultraviolet radiation removed less than 25% of PFASs, but ozonation-biological activated carbon (O-3-BAC) was superior to GAC alone in removing PFASs. Loose deposits couldsignificantly influence PFAS accumulation and release within branch-structured DWDSs. In loop-structured DWDSs, finished water with different PFAS characteristics could mix along the pipeline, with the corresponding DWTP as the center, ultimately forming a relatively uniform distribution in the entire DWDS. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Long-distance raw water transportation pipelines can remove PFAS contamination to a certain extent, while the South-to-North water diversion may increase PFASs pollution risk. The combination of ozonation-biological activated carbon is more effective in removing PFASs in drinking water treatment plants. The pipeline structure and deposits can significantly influence PFAS accumulation and release.