New research suggests exposure to some common Pfas or “forever chemical” compounds causes changes to gene activity, and those changes are linked to health problems including multiple cancers, neurological disorders and autoimmune disease.
The findings are a major step toward determining the mechanism by which the chemicals cause disease and could help doctors identify, detect and treat health problems for those exposed to Pfas before the issues advance. The research may also point toward other diseases potentially caused by Pfas that have not yet been identified, the authors said.
The study is among the first to examine how Pfas chemicals impact gene activity, called epigenetics.
“This gives us a hint as to which genes and which Pfas might be important,” said Melissa Furlong, a University of Arizona College of Public Health Pfas researcher and study lead author.
Pfas are a class of about 15,000 compounds most frequently used to make products water-, stain- and grease-resistant. They have been linked to cancer, birth defects, decreased immunity, high cholesterol, kidney disease and a range of other serious health problems. They are dubbed “forever chemicals” because they do not naturally break down in the environment
The study checked the blood of about 300 firefighters from four departments across the country who were exposed to high levels of Pfas. The chemicals are the main ingredient in most firefighting foam, and are frequently used in “turnout gear” worn by firefighters because of their heat repelling properties
Furlong said she was surprised to find the number of genes and biological pathways that were impacted by Pfas, which suggests the chemicals may cause or contribute to a broad range of health problems. The study did not prove the chemicals cause certain diseases, but findings point to biological changes that might precede disease.
Genes play a range of roles in developing or preventing disease, and Pfas essentially change the way the genes are supposed to act, Furlong said. A gene may act as tumor suppressor, but the Pfas interferes with how it expresses, which affects whether cancer develops, or the type of cancer.
For example, PFOS, among the most common and dangerous Pfas compounds, reduces levels of miR-128-1-5p, a gene tied to cancer development. Branched forms of PFOS were linked to changes in five other genes, including some that regulate cancer development.
Different Pfas and chemical structures were found to affect different genes, and were associated with different health outcomes. Not all compounds impacted gene expressions.
The research found connections among Pfas-related gene changes and biological pathways involved in leukemia, as well as bladder, liver, thyroid and breast cancers. Other genes and biological pathways were involved in Alzheimer’s disease, and autoimmune and infectious diseases such as lupus, asthma and tuberculosis.
Furlong said it remains unclear at which step in the biological processes disease is triggered, but the picture is clear enough to point to possible treatments. Pharmaceutical companies are trying to develop drugs that could alter gene activity and potentially prevent Pfas-linked disease from developing.
