A recent study published in Environment International has shown that synthetic ‘forever chemicals,’ known as perfluoroalkyl substances (PFAS), can be absorbed through human skin, potentially reaching the bloodstream. PFAS are commonly used in various industries and consumer products due to their water and stain repellent properties, despite concerns about their toxic effects. While some PFAS have been banned, others are still widely used, and their impact on human health is not fully understood. PFAS are already known to enter the body through other routes such as ingestion or inhalation, causing adverse health effects like impaired liver function and decreased birth weight.
Traditionally, it was believed that PFAS could not penetrate the skin barrier, but recent studies have suggested a possible link between the use of personal care products and PFAS concentrations in human blood and breast milk. The new study, conducted by Dr Oddný Ragnarsdóttir and her team at the University of Birmingham, provides the most comprehensive assessment to date of PFAS absorption through human skin. The researchers investigated 17 different PFAS, chosen based on their widespread use and known toxic effects. Using 3D human skin equivalent models, the team found that 15 of the PFAS tested showed significant dermal absorption, with some substances absorbed much more easily than others.
The study also revealed that absorption rates seemed to be influenced by the length of the carbon chain within the PFAS molecule. Substances with shorter carbon chains, like perfluoro pentanoic acid, were absorbed more readily compared to those with longer chains. This is significant as many industries have started using PFAS with shorter chain lengths in the belief that they are less toxic, despite the potential for higher absorption rates. According to Dr Mohamed Abdallah, one of the study’s co-authors, future research should focus on assessing the risks associated with exposure to a wider range of PFAS, rather than individual chemicals, to better understand their impact on human health.
Lead researcher Dr Oddný Ragnarsdóttir emphasized that the study challenges the traditional belief that PFAS cannot be absorbed through the skin due to their ionized nature. The findings suggest that skin absorption could be a significant source of exposure to harmful chemicals, contradicting previous assumptions about the limitations of skin as a barrier. According to Professor Stuart Harrad, another co-author of the study, understanding the significance of dermal exposure to PFAS is crucial for assessing the potential risks associated with these chemicals and determining which chemical structures are more easily absorbed.
This groundbreaking research not only provides new insights into the absorption of PFAS through human skin but also highlights the need for further studies to evaluate the risks posed by these toxic chemicals. With a shift towards using PFAS with shorter chain lengths, it is important to consider the potential consequences of increased absorption rates. By focusing on a broader range of PFAS rather than individual chemicals, future research can help to better understand the risks associated with exposure to these substances. This study underscores the importance of investigating all possible pathways of exposure to PFAS to protect human health and inform regulatory decisions in the future.