Per- and polyfluoroalkyl substances on the surface of children's feeding smocks: High-throughput characterization and implications for exposure assessment

Surfaces of objects are notable reservoirs for per - and polyfluoroalkyl substances (PFASs), representing a significant source of human exposure. However, precise concentration profiles for high-contact surfaces are scarce, owing to the lack of reliable analytical methods. Herein, a high-throughput method was proposed for the simultaneous quantification of both ionic and neutral PFASs on object surfaces. PFASs were collected using glass fiber wipes and directly introduced into the GC–MS through thermal desorption coupled with online derivatization, eliminating the solvent extraction step and significantly improving analytical efficiency. The proposed method was applied to measure PFAS concentrations on the surfaces of children's feeding smocks. Fluorotelomer alcohols (FTOHs) and fluorotelomer acrylates (FTACs) were identified as the predominant PFASs on both the outer and inner surfaces, with median concentrations ranging from 3.9 to 115 μg/m 2 . Notably, considerable differences in the concentration of 10:2 FTAC were observed between the outer and inner surfaces of these smocks, likely due to variations in garment manufacturing processes. Additionally, using the PFAS concentrations measured on the outer surface, the estimated exposure dose through hand-to-mouth contact ranged from 2.7 × 10 −3 to 5.5 × 10 −2 μg/kg bw/d for those neutral species. These exposure levels are comparable to those associated with indoor dust and air, highlighting the importance of considering treated garments as a potential source of PFAS contamination. • An in-situ PFAS sampling method with online derivatization is introduced. • Both ionic and neutral PFASs on surfaces can be simultaneously quantified. • Inner and outer smock surfaces exhibit distinct PFAS distribution patterns. • Children's smocks may pose a potential PFAS exposure risk.