Per- and Polyfluoroalkyl Substances in North American School Uniforms.
Level 5 - mechanism / opinion, no new human data
Analytical chemistry and exposure modeling study of commercial textile samples without human subjects; Level 5 by design analogy.
PubMed 36129192 · doi:10.1021/acs.est.2c02111
What was done
Researchers analyzed 72 children's textile products marketed as stain-resistant from US and Canadian stores, focusing on school uniforms. Products were screened for total fluorine using particle-induced gamma-ray emission (PIGE) spectroscopy (n = 72), followed by targeted analysis of 49 neutral and ionic PFAS (n = 57). Hydrolysis and total oxidizable precursor assays were performed to evaluate perfluoroalkyl acid precursors, and children's dermal exposure alongside US annual PFAS substance flow were modeled.
What was found
PFAS were detected in 100% of tested products, with 6:2 fluorotelomer alcohol (6:2 FTOH) being the most abundant compound. Total targeted PFAS concentrations ranged from 0.250 to 153,000 ng/g (median: 117 ng/g) or 0.0281 to 38,100 μg/m2 (median: 24.0 μg/m2). School uniforms had significantly higher total targeted PFAS levels than bibs, hats, stroller covers, and swimsuits, but comparable levels to outdoor wear. 100% cotton uniforms had higher concentrations than synthetic blends. Precursors were abundant. The estimated median potential dermal exposure for children wearing uniforms was 1.03 ng/kg bw/day, and estimated total PFAS usage in US children's uniforms was ~3 tonnes/year (range: 0.05 to 33 tonnes/year).
Why it matters
This study identifies stain-resistant school uniforms as a direct and ongoing source of childhood PFAS exposure, highlighting that millions of school children regularly wear garments treated with volatile and nonpolymeric fluorinated compounds.
Limits
The study is an in vitro chemical analysis of a retail sample set (n = 72) without direct human biological measurements or pharmacokinetic absorption assays. Exposure doses and nationwide substance flows are mathematical estimates rather than directly measured in vivo absorption.
Cited by
- supports PFAS chemicals are added to stain- and water-resistant fabrics and clothing, including flight attendant uniforms, firefighter gear, sportswear, and children's school uniforms.