Zhang Yu, Professor, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences
Fluorotelomer alcohols(FTOHs), the most well-known precursors and substitutes of perfluoroalkyl carboxylic acids(PFCAs), have been widely used in thetextile industry as water proofing. Municipal wastewater treatment plants(WWTPs) were considered as one of emerging contaminants in to the environment. But limited information was available on occurrence and fate of FTOHs in municipal WWTPs, and the influence of textile manufacturing waste water on occurrences of FTOHs in municipal WWTPs. Thus, the occurrence of six FTOHs in 12 municipal WWTPs of China and the mass balance ofF TOHs and PFCAs in one WWTP with ananaerobic-anoxic-oxicprocess (A/A/O) was explored. And the long-term trend of FTOH concentrations and profiles in 2013-2021 in a WWTP receiving discharges from the textile manufacturing industry (T-WWTP) and other four domestic WWTPs (D-WWTPs) were investigated. This study found that FTOHs were widely detected in municipal WWTPs and 8:2 FTOH was the predominant congener. The mass balance analysis found the decrease of FTOHs mass loads and the increase of PFCAs mass loads through aerobic treatment, suggesting the potential biotransformation of FTOHs to PFCAs. For the long-term investigation, the total concentrations of FTOHs in wastewater and sludge samples of the T-WWTP were significantly higher than those of the D-WWTPs(p<0.01). The variation in FTOH concentrations of the T-WWTP was in accord with the variation in annual output of textile products in the sewer shed(p=0.005), which suggested the textile manufacturing industry as a significant discharge route for FTOHs to municipal WWTP. This study will improve our understanding on the occurrence, fate and source ofFTOHs in municipal WWTPs.