PFAS, the toxic “forever chemicals” found in water, food packaging and even human blood, may be even harder to contain than scientists realized.
A new study from the University at Buffalo, published in Environmental Science & Technology Letters, shows that many PFAS are more acidic than previous research suggested.
That acidity makes it easier for PFAS to dissolve in water and move through the environment. In practice, it means these chemicals may spread more quickly and more widely, increasing the chance of exposure through food and drinking water.
“These findings suggest that previous measurements have underestimated PFAS’ acidity. This means their ability to persist and spread in the environment has been mischaracterized, too,” said study author Alexander Hoepker, PhD, senior research scientist with the UB RENEW Institute.
The researchers tested 10 types of PFAS and three common breakdown products using a more precise experimental method. In several cases, they found that acidity values were dramatically different from older measurements. For example, GenX, a chemical that replaced one of the most notorious PFAS used in making nonstick coatings, was found to be about 1,000 times more acidic than previously reported.
The new data will help scientists better predict how PFAS behave in the environment, which is essential for developing cleanup strategies and assessing health risks.
“If we’re going to understand how these concerning chemicals spread, it’s very important we have a reliable method for the accurate determination of their pKa values,” said co-author Diana Aga, PhD, director of UB’s RENEW Institute and SUNY Distinguished Professor of Chemistry.
A chemical’s “pKa” tells scientists how easily it gives up a proton, which in plain terms helps predict whether it will dissolve and spread in water or stick to other surfaces.
PFAS are linked to health issues including cancer, immune suppression and hormone disruption. They are called “forever chemicals” because they don’t easily break down in nature and build up in people and animals over time. The Centers for Disease Control and Prevention has detected PFAS in the blood of 99% of Americans.
This research was supported by the National Science Foundation.