Family-based exposure assessment of legacy and alternative poly- and perfluoroalkyl substances (PFASs) by multiple pathways.

PFASs are persistent, amphiphilic chemicals that bioaccumulate and cause adverse health effects. Restrictions on major PFASs have increased exposure to precursors and alternatives, requiring examination of contamination from major sources and internal levels. We collected house dust (n = 45), dietary (n = 124), and serum (n = 123) from 48 families and analyzed 30 PFASs. Three PFCAs (PFOA, PFDA, and PFUnDA) and one precursor (6:2diPAP) showed detection rates >90 % in house dust. Among these compounds, 6:2diPAP showed the highest level, with median of 4.71 ng/g dry weight. In dietary, PFPeA (1.43 ng/g) and 6:2FTS (0.61 ng/g) had the highest medians and were detected in all samples. In serum, the highest median was PFOA (4.50 ng/mL), followed by linear (L)-PFOS (3.90 ng/mL), L-PFHxS (1.79 ng/mL), and PFNA (1.15 ng/mL) across all family groups. The study identified diet as a significant exposure pathway, underscoring the importance of dietary habits in PFASs intake. The estimated daily intake from PFOA for all family members exceeded the USEPA's threshold. Compared to the EFSA's threshold for a mixture of four PFASs, exceedances ranged from 18 % to 38 %. This study highlights the need for continuous monitoring and regulation of PFASs and their alternatives to mitigate health risks.