Perfluoroalkyl substances (PFAS), including Perfluorooctanoic acid (PFOA), are a family of human-made chemicals developed in the 1940s that are ubiquitous in the environment. These substances consist of a hydrophobic alkyl chain of fluorinated hydrocarbons of varying lengths and a hydrophilic end group (EFSA Panel on Contaminants in the Food Chain et al. 2018). Their unique chemical properties allow them to repel oil, grease, and water, which is why they are often used in surface protection products such as carpet, clothing treatments, and coatings for paper and cardboard packaging (Agency for Toxic Substances and Disease Registry (ATSDR) 2015). 

The chemical stability of PFAS, along with their environmental and biological persistence, have raised concerns about potential adverse human health effects. Yet, some argue that these concerns have been exaggerated. While drinking water and food consumption are among the most studied sources of PFAS exposure to humans, dermal uptake remains an often-overlooked pathway of exposure. However, based on the first principles, one would not expect dermal absorption to be very significant. The use of PFAS in bandages has drawn recent attention (Kluger 2024).

PFAS are used in various products due to their water-resistant and adhesive properties. In bandages, PFAS can be added to the pads to help resist moisture and to the flaps as an adhesive ingredient. This use takes advantage of PFAS’s ability to provide durability and water repellency, making bandages more effective in protecting wounds from moisture and ensuring they stay securely in place (Kluger 2024). Mamavation, a non-profit “consumer watchdog group,” conducted a study to identify the presence of PFAS in bandage products. According to the study, bandages were sent to an EPA-certified lab for testing to identify the presence of PFAS. Of the 40 bandages tested, 26 showed organic fluorine concentrations above 10 ppm, indicating a possible presence of PFAS chemicals at a 65% prevalence. Simply measuring the presence of fluorine chemicals, such as PFAS, does not directly indicate the potential for adverse effects. Factors such as concentrations, exposure pathways, duration of exposure, and toxicity data are necessary to determine risk.

The group noted that bandages marketed specifically to people of color exhibited a higher incidence rate of PFAS contamination, with 63% (10 out of 16 bandages) showing levels above 10 ppm. The detected organic fluorine levels ranged from 11 ppm to 328 ppm (0.011 to 0.328 mg/mL) (Segedie 2024). The method used by Mamavation’s lab involved determining total fluorine through oxygen flask combustion followed by measurement with an ion-selective electrode. This approach does not differentiate between various types of PFAS nor does it specify their concentrations. The group did not conduct a risk assessment to determine absorption, penetration to the blood stream, or dose. 

Currently, dermal absorption of PFAS is less investigated than the oral pathway. In one study, PFOA was detected in the serum of mice following dermal application of the compound dissolved in acetone (Franko et al. 2012). However, studies have also shown that rat and mouse skin are often more permeable to PFOA than human skin (van Ravenzwaay and Leibold 2004). In a recent study, Ragnarsdottir et al. (2024) examined dermal exposure to PFAS using in vitro reconstructed human epidermis and found that absorption decreased with increasing carbon chain length. Again, by itself, these data are only the first step in identifying a human health hazard.

Direct skin contact with PFAS compounds through consumer products like cosmetics, household cleaning products, and industrial protective gear poses a risk of dermal absorption. However, estimated absorbed doses due to these products are anticipated to be too low to pose a hazard to human health. To address consumers’ concerns, a high-quality risk assessment is needed.

How Paustenbach & Associates Can Help

Litigation associated with dermal exposures to PFAS has recently skyrocketed. The only way to ensure that the public and juries reach sound decisions about exposures to these chemicals is to conduct a proper health risk assessment with respect to PFAS. Based on some screening level assessments that we have performed and risk assessments, we believe that these chemicals would be considered safe for the vast majority of Americans who apply consumer products to their skin.

Scientists at Paustenbach & Associates have over 55 years of experience in conducting risk assessments of dermal exposure to chemicals, including shampoos, cleansing conditioners, rinse-off and leave-on personal care, as well as cosmetic products and fragrances (Monnot et al. 2016; Drechsel et al. 2018; Towle et al. 2018).  We have been studying the PFAS chemical family for several years and our scientists are prepared to assist clients facing PFAS challenges.

We have testified in more than 500 depositions and 50+ trials over the years during which we presented our risk analyses. In the cases in which we were retained, we applied exposure science and the health risk assessment methodology embraced by the National Academies of Science to characterize the possible risks. Over the years, we have conducted more than 1,000 risk assessments. Please contact Dr. Careen Khachatoorian for more information regarding our capabilities at ckhachatoorian@paustenbachandassociates.com or 951-436-0099.

References

Agency for Toxic Substances and Disease Registry (ATSDR). 2015. Draft toxicological profile for perfluoroalkyls. U. S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry. 

Drechsel DA, Towle KM, Fung ES, Novick RM, Paustenbach DJ, Monnot AD. 2018. Skin Sensitization Induction Potential From Daily Exposure to Fragrances in Personal Care Products. Dermatitis. 29(6): 324-331.

EFSA Panel on Contaminants in the Food Chain, Knutsen HK, Alexander J, Barregard L, Bignami M, Bruschweiler B, et al. 2018. Risk to human health related to the presence of perfluorooctane sulfonic acid and perfluorooctanoic acid in food. EFSA Journal. 16(12): 1-284.

Franko J, Meade BJ, Frasch HF, Barbero AM, Anderson SE. 2012. Dermal penetration potential of perfluorooctanoic acid (PFOA) in human and mouse skin. Journal of Toxicology and Environmental Health, Part A. 75(1): 50-62.

Kluger J. 2024. Evidence of Dangerous ‘Forever Chemicals’ Found in Bandages. Time Magazine. April 5, 2024. 

Monnot AD, Tvermoes BE, Gerads R, Gurleyuk H, Paustenbach DJ. 2016. Risks associated with arsenic exposure resulting from the consumption of California wines sold in the United States. Food Chemistry. 211: 107-113.

Segedie L. 2024. Band-Aids & Bandages with Indications of PFAS “Forever Chemicals” Report. Mamavation.com. 

Towle KM, Drechsel DA, Warshaw EM, Fung ES, Novick RM, Paustenbach DJ, Monnot AD. 2018. Risk Assessment of the Skin Sensitization Induction Potential of Kathon CG in Rinse-off and Leave-on Personal Care and Cosmetic Products. Dermatitis. 29(3): 132-138.

van Ravenzwaay B, Leibold E. 2004. The significance of in vitro rat skin absorption studies to human risk assessment. Toxicology in Vitro. 18(2): 219-225.