They Are Getting Closer: PFAS Found to Be Capable of Passing Through Human Skin

Forever chemicals, known scientifically as per- and polyfluoroalkyl substances (PFAS), are ubiquitous, appearing in products such as school uniforms, food packaging, cosmetics, and even drinking water. These chemicals have now been found to penetrate human skin, raising concerns about an additional exposure pathway. For over half a century, major corporations were aware of the toxicity of some PFAS compounds. Documents from as far back as 1961 indicate that DuPont, the maker of Teflon, had information about the potential hazards, including skin contact risks. This is prepared by SSP.

Recent studies indicate these persistent compounds can cross the skin barrier. Utilizing 3D human skin models, scientists applied PFAS dissolved in methanol to observe their behavior. Out of 17 analyzed chemicals, 11 managed to traverse the skin membrane. Shorter-chained PFAS such as perfluoropentanoic acid (PFPeA) and perfluorobutane sulfonate (PFBS) showed higher absorption rates, with approximately 59 percent of PFPeA and 49 percent of PFBS entering the skin and potentially reaching the bloodstream.

This significant discovery highlights similarities and differences in absorption rates, rigorously tested with lab-grown epidermis models. The studies extended up to 36 hours, illustrating that PFAS exposure, even through skin-contact products like cosmetics and clothes, can infiltrate the dermis. There are substantial questions about the everyday concentrations of PFAS compared to those used in lab settings. Nonetheless, environmental scientists maintain that the implications are compelling.

Furthermore, the studies show the skin's absorption capabilities can vary across different areas of the body—thicker in places like the feet and thinner in regions such as the genital area, affecting the degree of PFAS permeation. Experiments have even demonstrated that some PFAS variants present in personal care products, such as sunscreens, can absorb through the skin into the bloodstream, necessitating further research on the potential toxicity and systemic distribution of these chemicals.

In the U.S., the significant exposure routes include food packaging, indoor dust, and contaminated drinking water. Consequently, the U.S. Environmental Protection Agency (EPA) set stringent guidelines to limit PFAS intake through drinking water in mid-2022. However, the underestimated dermal absorption route remains concerning.

Both studies conclude that our awareness and avoidance of PFAS-infused products may need to increase due to the cosmetic industry's prevalent use. While methods like 3D skin models offer substantial insights, there's a call for more extensive data and human-based research to fully understand the impact and strategize appropriate preventative measures.