If you’ve ever used non-stick cookware or enjoyed water-repellency on a rain jacket or tent flysheet, chances are you’ve used products made with PFAS (Per- and polyfluoroalkyl substances). Sought after for their ability to repel water, grease, and oil, PFAS are a class of more than 4700 synthetic compounds manufactured and used globally since the 1950s. Their chemical properties make them effective as repellents, but they are persistent in the environment and human body, with the propensity to accumulate over time.
Humans and ecosystems are exposed to PFAS through contaminated water, polluted air, and contact with PFAS-containing items. One application poorly studied in North America is PFAS use in cosmetics like foundation, lipstick and waterproof mascara. So a team of scientists from the US and Canada recently tested a range of commercially available cosmetics to establish how much PFAS they contained, publishing their results in June 2021 in Environmental Science & Technology Letters.
The team analyzed 231 cosmetics obtained between 2016 and 2020 from beauty retailers and drugstores in Indiana and Michigan in the US and Toronto in Canada. The study was led by Heather Whitehead at the University of Notre Dame, with fifteen US and Canadian colleagues, including Miriam Diamond at the University of Toronto.
Using particle accelerators at Hope College in Michigan and the University of Notre Dame in Indiana, the team used particle-induced gamma-ray emission (PIGE) spectroscopy to screen the total fluorine concentrations of each product. They then targeted a subset of 29 products for liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatographic mass spectrometry (GC-MS). The team also examined US and Canadian regulatory practices for PFAS use and disclosure on ingredient labels.
“We found quite a variety,” says Diamond. Some compounds had low PFAS quantities, while others had relatively high amounts. Of the eight categories tested, foundations, mascaras, and lip products had the most significant proportion of high total fluorine at levels of at least 0.384 μg F/cm2. Targeted analyses on twenty-nine products revealed PFAS concentrations ranging from 22–10,500 ng/g product weight, with an average of 264 ng/g.
“Among the highest concentrations in the targeted analysis were 6:2 FTOH and 8:2 (fluorotelomer alcohol) that is known to transform to the carboxylic acid form,” explains Diamond. For the 8:2 FTOH, the oxidation product is perfluorooctanoic acid (PFOA). “We also found 6:2 (and some 8:2) fluorotelomer methacrylate,” Diamond says. These compounds, precursors to perfluoroalkyl carboxylic acids (PFCAs), are persistent, so manufacture, use, and disposal of cosmetics containing PFAS note the study team, represent potential opportunities for health and ecosystem harm.
PFAS are multi-system toxicants, explains toxicologist Jamie DeWitt at the Brody School of Medicine at East Carolina University in Greenville, North Carolina. She focuses on PFAS immune impacts. One effect is “reduced ability of the body’s response to a vaccine, which is pretty concerning considering that vaccines are really important right now,” she says.
PFAS can also cause liver damage, increase human cholesterol levels, and are linked to thyroid disease, decreased birth rates, pregnancy-induced hypertension and pre-eclampsia, and kidney and testicular cancer. Those are effects known from epidemiological and experimental data. However, “we don’t have a clear understanding of how they operate on a molecular level,” DeWitt says. What is known is that they interact with many different cellular receptors.
In cross-referencing quantitative analyses with cosmetic ingredient labels, Whitehead’s team found that most products did not disclose their fluorinated compounds, highlighting a gap in US and Canadian labelling laws. However, to be clear, says Diamond, “I’m not asking for stricter labelling. I am actually asking to get rid of PFAS in cosmetics,” adding that removing them protects everybody, including those who don’t read labels.
“Why are we using chemicals that we know are persistent in a product where it’s not essential?” asks Diamond. In the US, a bill to phase out the use of PFAS in cosmetics recently received bipartisan support. Diamond hopes to see Canadian regulatory agencies moving in the same direction, applauding a recent government announcement to consider PFAS a chemical class. “This is a really big deal,” says Diamond. Without this development to subsume thousands of chemicals under one umbrella, regulation must proceed on a chemical by chemical basis.