New Study Links PFAS Exposure to Increased Brain Neurotoxicity

Some forever chemicals, such as PFOA, impact genes responsible for regulating brain functions, including those involved in cell death.

The findings of a new study indicate that exposure to per- and polyfluoroalkyl substances (PFAS) can alter the expressions of certain genes, both increasing neurotoxicity, and potentially giving doctors a way to track or detect exposure.

In a report published last month in the medical journal ACS Chemical Neuroscience, researchers from the University of Buffalo demonstrated their ability to detect alterations in gene expression in brain cells exposed to PFAS, commonly known as “forever chemicals.” Their findings show that these alterations reveal whether specific genes were activated or suppressed, with different types of PFAS affecting genes in unique ways.

PFAS consist of a group of more than 9,000 man-made chemicals, which have been widely used in a number of products over the past few decades, to resist grease, oil and water. However, the chemicals are known to persist in the environment and build up in the human body, causing a number of serious health effects, including kidney cancer, testicular cancer, ulcerative colitis and other serious diseases.

The majority of concerns over PFAS exposure have stemmed from water contamination issues caused by their heavy use in aqueous film-forming foam (AFFF), which has been used by military and civilian firefighters to fight fuel-based fires.

The research team, led by Drs. G. Ekin Atilla-Gokumen and Diana Aga, exposed different types of brain cells for 24 hours to only a few dozen microns of six different kinds of PFAS:

• perfluorooctanoic acid (PFOA)
• perfluorooctanesulfonic acid (PFOS)
• perfluorodecanoic acid (PFDA)
• perfluorodecanesulfonic acid (PFDS)
• 8:2 fluorotelomer sulfonate (8:2 FTS)
• 8:2 fluorotelomer alcohol (8:2 FTOH)

They then investigated what effects the exposures had on the brain cells.

The researchers discovered that PFAS exposure influenced the activity of over 700 genes in brain cells, with 11 genes consistently impacted across the board. PFAS altered the activity levels of these genes, either amplifying or diminishing their effects. For instance, PFAS reduced the activity of a gene critical for brain cell survival, while increasing the activity of another gene associated with brain cell death, thereby contributing to neurotoxicity.

However, the effects of each type of PFAS varied greatly. For example, PFOA, used in non-stick cookware, stain resistant carpets and AFFFs, had a stronger effect on genes regulating cell survival and death than other types of PFAS. In addition, some PFAS increased gene expressions, while others might decrease them.

“Depending on their chain length or headgroup, PFAS can have very different effects on cells,” Atilla-Gokcumen stated in a University of Buffalo press release. “We should not be viewing them as one large class of compounds, but really as compounds that we need to investigate individually.”

The researchers suggest that these findings provide valuable insights into PFAS-induced neuronal dysfunction and could pave the way for methods to detect PFAS exposure and identify specific types based on their impact on gene expression.

PFAS Exposure Lawsuits

This latest study’s findings come as chemical manufacturers like 3M Company, DuPont and BASF face thousands of PFAS water contamination lawsuits filed by water providers and individuals diagnosed with various types of cancer, as well as firefighter PFAS injury lawsuits brought by individuals who came into direct contact with the chemicals.

Given common questions of fact and law raised in PFAS injury and exposure lawsuits brought throughout the federal court system, the litigation has been consolidated under U.S. District Judge Richard M. Gergel in South Carolina, for coordinated pretrial proceedings as part of an MDL, or multidistrict litigation.

As part of the coordinated management of the litigation, a small group of early PFAS contamination lawsuits are being prepared for trial dates later this year, involving claims that individuals developed testicular cancer, kidney cancer, liver cancer, thyroid cancer, thyroid disease and ulcerative colitis, after drinking water known to be contaminated with high levels of the chemicals.

While the outcome of these early trial dates will not have any binding impact on other claims being pursued throughout the federal court system, they are designed to help gauge how juries may respond to certain evidence and testimony that will be repeated throughout the litigation.