6:2 Fluorotelomer Ethoxylates in Human Serum and Residential Homes: A Growing Environmental Health Concern

As an emerging group of per- and polyfluoroalkyl substances (PFAS), fluorotelomer ethoxylates (FTEOs) are widely employed as a major ingredient in antifog products. However, knowledge about their environmental distribution and human exposure remains scarce. Herein, we reported the ubiquitous detection of 6:2 FTEO homologues in popular antifog products (<i>n</i> = 47), indoor dust from residential homes (<i>n</i> = 80), and serum of pregnant women (<i>n</i> = 90) living in South China, demonstrating broad use and widespread human exposure. The cumulative concentrations of 6:2 FTEOs ranged from below the limit of detection (<LOD) to 2600 ng/g (median: 21.7 ng/g) in house dust and from <LOD to 24.9 ng/mL (median: 0.40 ng/mL) in human serum. 6:2 FTEO8, 6:2 FTEO9, 6:2 FTEO10, and 6:2 FTEO11 appeared to be the dominant homologues consistently found in antifog products, house dust, and human serum. Molecular docking revealed a high binding affinity of major 6:2 FTEO homologues to human serum albumin and liver fatty acid binding protein, suggesting substantial bioaccumulation potency and potential biological effects. As the first report on human exposure to 6:2 FTEOs, our study calls for further monitoring and toxicological investigations to better understand the potential risks of this specific group of PFAS to human health.