Tests find high levels of PFAS in one-third of dental floss brands

ehn.org

27 points·Jimmc414··3 comments

But how bad is that amount for me really?

The EPA recently changed drinking water recommendations for PFOA at 0.004 part per trillion (ppt) and for PFOS, 0.02 ppt. [0] and if my math is correct, 248,000 ppm equates to 2.489e+11 ppt [1] which please correct me if I am wrong, puts Oral-B Glide at 1.2445e+13 times the EPA recommendation for drinking water. While obviously ingesting floss isn't the same as drinking water but that still seems high to me. Like so high that I must have made an error somewhere.

[0] https://cen.acs.org/environment/persistent-pollutants/US-EPA...

[1] https://www.calculatorology.com/ppm-to-ppt-converter/

It's because this reporting is nonsense. It comes from a health influence with "mama" in the name, always a good indicator of scientific rigor.

They say they tested for "organic fluorine", and when it predictably came back positive they crowed that the floss contains the kind of PFAS that has been loosely correlated with health effects (such as the small-molecule chemicals PFOA, PFOS, or Gen-X). But if they had any familiarity with chemistry or the products they were testing, they'd have known that what they actually found is plain old Teflon, which is the most biologically inert substance in common use, does not emit volatile PFAS, and is not (yet) under regulatory scrutiny.

Your floss is perfectly safe.

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