Forever chemicals ‘absorbed through skin’

Synthetic ‘forever chemicals’ can readily be absorbed through human skin, a study of 17 commonly used toxic substances has shown.

A wide range of chemicals which do not break down in nature can permeate the skin barrier and reach the body’s bloodstream, according to new research published in Environment International. These chemicals are known to cause adverse health effects such as a lowered immune response to vaccination, impaired liver function and decreased birth weight. 

The perfluoroalkyl substances (PFAS) are used widely in industries and consumer products from school uniforms to personal care products because of their water and stain repellent properties. While some substances have been banned, others are still widely used and their toxic effects have not yet been fully investigated. 

Toxic

Dr Oddný Ragnarsdóttir, the lead author of the study who carried out the research while studying for her PhD at the University of Birmingham, said: “The ability of these chemicals to be absorbed through skin has previously been dismissed because the molecules are ionised. 

“The electrical charge that gives them the ability to repel water and stains was thought to also make them incapable of crossing the skin membrane. Our research shows that this theory does not always hold true and that, in fact, uptake through the skin could be a significant source of exposure to these harmful chemicals.” 

Dr Mohamed Abdallah, a study co-author, said: “Our study provides a first insight into the significance of the dermal route as a pathway of exposure to a wide range of forever chemicals. Given the large number of existing PFAS, it is important that future studies aim to assess the risk of broad ranges of these toxic chemicals, rather than focusing on one chemical at a time.”  

Absorption

Professor Stuart Harrad of the University of Birmingham’s School of Geography, Earth and Environmental Sciences, also a study co-author, said: “This study helps us to understand how important exposure to these chemicals via the skin might be and also which chemical structures might be most easily absorbed.