Association Between Serum Levels of Perfluoroalkyl and Polyfluoroalkyl Substances and Dental Floss Use: The Double-Edged Sword of Dental Floss Use-A Cross-Sectional Study.
Level 4 - case-series / case-control
Cross-sectional survey analysis (NHANES)
PubMed 39797715 · doi:10.1111/jcpe.14126
What was done
The authors evaluated the relationship between self-reported dental floss use and serum concentrations of six perfluoroalkyl and polyfluoroalkyl substances (PFASs) using National Health and Nutrition Examination Survey (NHANES) data from 2009 to 2020. The sample comprised 6,750 U.S. adults. Statistical adjustments and analyses included logistic regression, survey-weighted linear models, item response theory scores, inverse probability weighting, and sensitivity analyses.
What was found
Dental floss users had higher serum concentrations of perfluorooctanoic acid (PFOA) compared to non-users, an increase that remained statistically significant in sensitivity analyses. Conversely, floss users had lower serum concentrations of the other measured PFASs and a lower overall composite PFAS burden score compared to non-users. Specific numerical concentrations, effect sizes, and odds ratios were not reported in the abstract.
Why it matters
Certain dental floss products have been suspected of containing PFAS coatings, and this study provides population-level evidence linking flossing specifically to higher serum PFOA, while paradoxically finding lower total PFAS burdens.
Limits
The cross-sectional design cannot establish causality or determine whether PFOA came directly from floss. Floss use was self-reported, specific floss brands or material types were not captured in the abstract, and exact numerical estimates were not provided.
Cited by
- context Dental floss contains PFAS chemicals.