Notre Dame's St. Andre accelerator, which is used to perform particle-induced gamma-ray emission (PIGE) ion beam analysis. Credit: Matt Cashore/University of Notre Dame
A university of Notre Dame researcher has published their findings after testing a wide assortment of reusable feminine hygiene products for PFAS, the results of which suggest that PFAS may have been intentionally used during manufacturing. While most samples tested, around 71%, contained concentrations of PFAS low enough to be considered "non-intentionally fluorinated", 33% of period underwear and 25% of reusable pads had rates the team deemed "intentional fluorination."
The study, published in Environmental Science & Technology Letters, relied on particle-induced gamma-ray emission (PIGE) spectroscopy to test more than 70 products sourced from markets in North America, South America, Europe, and Asia-pacific which included period underwear, reusable pads, menstrual cups and reusable incontinence underwear.
By employing the ion beam analysis technique, the team could determine the total fluorine content based on the gamma rays emitted by the fluorine nuclei. In products with multiple layers, the team tested each layer of the product, totaling 323 unique samples analyzed using PIGE.
With previous studies suggesting that skin absorption could be a significant pathway for PFAS exposure, the findings are particularly concerning for these products which come into direct contact with a wearers skin.
Even with their latest results, Graham Peaslee, a physicist at the University of Notre Dame, points out that "there's still a lot we don't know about the extent to which PFAS are being used in the manufacturing of these products, and too much we don't know about the potential for these chemicals to be absorbed through the skin by the consumers who wear them."
Another significant concern of the study is that currently, only a small portion of companies making reusable feminine hygiene products use PFAS intentionally.
"Only a subset of the products had high levels of PFAS present, which means that PFAS must not be essential in the manufacture of reusable feminine hygiene products," added Alyssa Wicks, lead author of the study.
"This is good news in that it demonstrates PFAS are not required to produce these environmentally conscious products, and manufacturers should be able to make these textile products without chemicals of concern in them."
The authors did not identify PFAS concentrations by brand in their study.