Occurrence of per- and polyfluoroalkyl substances in indoor dust from a University in Eastern China and their association with residents' hair levels.

Abstract

Per- and polyfluoroalkyl substances (PFAS) have attracted attention because of their persistence and widespread occurrence in indoor environments. This study investigated the occurrence, distribution, and exposure risks of PFAS in indoor dust from different university environments. The associations between indoor dust and hair PFAS concentrations were explored. The average ∑PFAS concentration in dust from unrenovated dormitories (Type Ⅱ, 126.61 ng/g) exceeded that in renovated dormitories (Types Ⅰ and Ⅲ, 63.81 and 54.65 ng/g, respectively). Hair samples from students across all three dormitory types showed PFAS accumulation, with perfluorooctanoic acid (PFOA) as the dominant compound (75.46%, average: 1.15 ng/g). PFAS burdens in hair varied markedly across dormitory types, with average ∑PFAS concentrations of 4.67 ng/g for Type Ⅰ (renovated), 1.00 ng/g for Type Ⅲ (renovated), and 0.49 ng/g for Type Ⅱ (unrenovated). Significant positive correlations between ∑PFAS concentrations in dust and hair (r = 0.77, p < 0.01) suggest that indoor dust may represent a potential contributor to PFAS accumulation in human hair, highlighting the potential of hair as a non-invasive biomonitoring matrix for long-term PFAS exposure. Although the estimated exposure risks were relatively low, the widespread occurrence of PFAS highlights indoor environments as a potential source of chronic human exposure.