PFAs: Controversy over Chemicals may Surface with Some Dental Floss

© Asier / Adobe Stock

Recently, many dental hygienists caught wind of controversy over PFAs in floss. While some may be on alert and highly concerned regarding this issue, others may not be even remotely invested in the hype.

As of writing this article, I have not been confronted by any of my patients on the matter. But I felt it was important to arm myself with a wealth of knowledge to thoroughly answer and address any concerns my patients may have.

What are PFAs?

PFAs stand for per- and polyfluoroalkyl substances and are a group of manufactured chemicals that have been used in industry and consumer products since the 1940s.1 Two of the most widely used and studied chemicals in the PFA group are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS).

In recent years, however, these two have been replaced with other PFAs ‒ most often with one called GenX. GenX is composed of hexafluoropropylene oxide (HFPO), dimer acid, and ammonium salt. According to an evaluation by the Environmental Protection Agency, GenX is just as, if not more, toxic than PFOAs.3,4

PFAs are used for many reasons, including keeping food from sticking to cookware, helping to make clothes stain resistant, and creating a more effective firefighting foam. The military, aerospace, automotive, and construction industries all use PFAs in their industry. PFAs are comprised of a chain of linked carbon and fluorine atoms ‒ one of the strongest bonds that do not degrade in the environment, lending them the title “forever chemicals.”2,5

Unfortunately, you will not only find these chemicals in products but also in water, air, and soil due to contamination. In 2017, the southeastern coastal town of Wilmington, North Carolina, was highlighted in the news after the discovery of the rampantly contaminated water supply with GenX after two manufacturer supply companies knowingly dumped PFAs in the water supply for over a period of four decades.5 Many residents blame ongoing health issues such as cancer to this exposure.

PFAs Effects on Health

Ongoing studies are trying to help shed light on the broad range of health effects of PFA exposure. Current peer-reviewed studies reveal that exposure to certain levels can initiate the following:

  • Reproductive effects such as decreased fertility and high blood pressure during pregnancy
  • Developmental defects or delays in children such as low birth weight and accelerated puberty and behavioral changes
  • Increased risks of cancer, including prostate, kidney, and testicular
  • Suppressed immune system
  • Hormone interference
  • Increased cholesterol levels1

Some studies noted an increased risk of liver and pancreatic tumors.6 Since children are still developing, they may be more sensitive to the health effects of PFAs and are more likely to be exposed than adults for various reasons.1 Children tend to put more things in their mouths and spend more time on the floor (carpet), which places them at a higher exposure risk in conjunction with the fact that children eat, drink, and breathe more air per pound of body weight than adults, also increasing exposure.

Studying the health effects of PFAs is challenging because there are thousands of PFAs to evaluate, multiple methods of transmission, and types and uses of PFAs change over time, making it difficult to track.

PFAs in Dental Floss

Some oral health companies use fluorine in their floss, suggesting that these flosses utilize the PFA technology to aid in the act of flossing. PFAs are slippery and, therefore, used in floss to assist in gliding the floss between the teeth. A new study suggests that those who use floss with PFAs may absorb those toxic chemicals through saliva or the hands. The study went on to conclude that women who used floss containing fluorine had higher levels of perfluorohexane sulfonic acid (PFHxS), a type of PFA, than those who did not.7,8 The study did admit that other exposure factors were noted and that this study helps to strengthen the evidence that consumer products are a source of PFA exposure.

PFAs are growing in numbers, and our exposures are broad. Until we can help eliminate or replace the PFAs in our products with safer chemicals, it is definitely within our reach to control the self-inflicted oral health exposures. Patients are sure to hear about this newer headline, especially those more environmentally or health conscious.

Educating ourselves on the matter will help answer our patients’ questions and give them factual knowledge on what we know thus far about the health risk of PFAs. After all, getting patients to simply floss proves to be its own challenge!

Before you leave, check out the Today’s RDH self-study CE courses. All courses are peer-reviewed and non-sponsored to focus solely on high-quality education. Click here now.

Listen to the Today’s RDH Dental Hygiene Podcast Below:


  1. Our Current Understanding of the Human Health and Environmental Risks of PFAS. (2022, March 16). United States Environmental Protection Agency.
  2. Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS). (2022, June 17). NIH: National Institute of Environmental Health Sciences.
  3. Human Health Toxicity Assessments for GenX Chemicals. (2022, January 13). United States Environmental Protection Agency.
  4. Sorg, L. (2021, October 26). EPA: GenX Far More Toxic that Originally Thought, Could Prompt NC to Significantly Reduce Health Advisory Goal. N.C. Policy Watch.
  5. Greenfield, N. (2021, June 7). The Drinking Water Crisis that North Carolina Ignored. National Resources Defense Council.
  6. Per- and Polyfluoroalkyl Substances (PFAS). (2020, May). U.S. Department of Health and Human Services: National Toxicology Program.
  7. Some Dental Floss May Expose People to Harmful Chemicals. (2019). Harvard T.H. Chan School of Public Health.
  8. Boronow, K.E., Brody, J.G., Schaider, L.A. et al. Serum concentrations of PFASs and exposure-related behaviors in African American and non-Hispanic white women. J Expo Sci Environ Epidemiol. 2019; 29: 206–217.