Sweat-amplified dermal transfer and combined toxicity of per- and polyfluoroalkyl substances and organophosphate esters mixtures in children's textiles.

The widespread application of chemical additives in textiles raises concerns about dermal exposure, especially in children. We analyzed 28 per- and polyfluoroalkyl substances (PFAS) and 9 organophosphate esters (OPEs) in household textiles and children's garments. PFAS were detected in 87.9 % of samples, with significantly higher concentrations in household textiles (median: 668 ng/g) than children's garments (10.8 ng/g). Perfluorooctanesulfonic acid predominated, with some items exceeding the EU limit of 1 μg/m. OPEs were ubiquitous (median: 151 ng/g), dominated by triphenyl phosphate (79 ng/g). Durable-water-repellent garments contained approximately 3-fold higher PFAS and OPE concentrations than conventional functional items. Simulated laundering reduced additive OPEs (e.g., tributyl phosphate) but unexpectedly increased the detection of perfluorooctanoic acid. Dermal exposure modeling revealed that sweat markedly increased chemical absorption-up to 3252-fold for PFAS and 835-fold for OPEs-compared to dry contact. In vitro assays showed textile extracts reduced HaCaT cell viability, with mixture modeling identifying tributyl phosphate isomers as key contributors. These results highlight the underestimated risk of sweat-enhanced dermal exposure and mixture toxicity from treated textiles. Our findings support the need for improved textile safety standards and regulatory oversight to better protect vulnerable populations, especially children.