Dental floss made with PTFE, the same material as Teflon, has been the primary source of PFAS in floss products. The most well-known example was Oral-B Glide, though the company has since removed PFAS from its entire floss line. Other products that tested positive include Colgate Total floss (marketed as a “single-strand Teflon fiber”) and store-brand flosses labeled “compare to Oral-B Glide.”
Which Flosses Tested Positive for PFAS
A study by the Silent Spring Institute tested 18 dental floss products for fluorine, a chemical marker of PFAS. Six products tested positive: three types of Oral-B Glide floss, one Colgate Total product, and two store-brand flosses designed to mimic Glide. All six were made with PTFE (polytetrafluoroethylene), which is a type of PFAS polymer. PTFE is the same slippery, nonstick material used in Teflon cookware and Gore-Tex waterproof fabric.
The reason manufacturers used PTFE is straightforward: it slides between teeth with very little friction and resists shredding. That smooth, gliding feel that distinguished these products from traditional nylon floss came directly from the PFAS-based material.
Women in the study who flossed with Oral-B Glide had higher blood levels of a specific PFAS compound called PFHxS compared to women who used other flosses. As one researcher noted, nonstick pans have a larger surface area, but people don’t chew on them the way they do dental floss. The direct oral contact and friction of flossing may make it a more significant exposure route than its small size suggests.
Oral-B Glide Has Changed Its Formula
In a notable shift driven by the research findings, Oral-B eliminated PFAS from its entire Glide floss line. The company reports that its updated Glide products now use a micro-textured fiber instead of PTFE, and that none of its current floss products contain PFAS. If you’re buying Oral-B Glide today, it should be PFAS-free, though older stock could still be on some shelves.
How to Spot PFAS on Floss Packaging
Dental floss isn’t required to list every material on its packaging, which makes identifying PFAS tricky. There are a few signals to look for. The most obvious is any mention of PTFE, polytetrafluoroethylene, or Teflon in the product description. Colgate Total, for instance, openly marketed its floss as a “single-strand Teflon fiber.” Store brands that say “compare to Oral-B Glide” on the label were also found to contain PFAS in testing, since they were copying the PTFE-based formula.
If a floss feels unusually slick or is marketed with terms like “easy glide” or “smooth texture,” that’s worth a closer look at the materials, though it doesn’t guarantee PFAS is present. Nylon and polyester flosses with wax coatings can also feel smooth without any fluorinated compounds.
Flosses That Tested Free of PFAS
Twelve of the 18 products in the Silent Spring study had no detectable fluorine. These included a wide range of common brands:
- Oral-B Complete Deep Clean Ultra Mint and Satin Floss Mint
- Reach Mint Waxed, Waxed Unflavored, and Clean Paste Icy Mint Woven Floss
- Johnson & Johnson Listerine Cool Mint Floss
- Tom’s of Maine Naturally Waxed Antiplaque Flat Floss
- Desert Essence Tea Tree Oil Dental Tape
- EcoDent Gentle Floss with Essential Oils
- CVS Unwaxed
- Rite-Aid Premium Waxed Mint Floss
The common thread among PFAS-free options is their material: nylon or polyester thread, sometimes coated with natural or synthetic wax. These are the traditional floss materials that have been used for decades.
Why PFAS in Floss Matters
PFAS are often called “forever chemicals” because they don’t break down in the environment or in the human body. They accumulate over time with repeated exposure. The health concerns linked to PFAS exposure include liver damage, immune system suppression, developmental problems, and increased cancer risk. While a single flossing session involves a tiny amount of material, flossing is a daily habit that involves direct contact with soft oral tissue, creating a consistent low-level exposure over years.
Minnesota Now Bans PFAS in Dental Floss
Minnesota became the first state to explicitly ban PFAS in dental floss. As of January 1, 2025, dental floss containing intentionally added PFAS cannot be sold in the state under a law known as Amara’s Law. The ban covers any product designed to clean between teeth, including both traditional floss and dental tape. There are no exceptions or extensions for manufacturers who haven’t found alternatives. Dental floss is one of 11 product categories covered by the law, alongside cookware, cosmetics, and cleaning products.
No federal regulation specifically targets PFAS in dental floss yet, but Minnesota’s law signals a broader regulatory direction. If you live outside Minnesota and want to avoid PFAS in your floss, choosing products made from nylon or polyester and avoiding any that reference PTFE or Teflon remains the most reliable approach.