Underwear that protects against menstrual leaks have become hugely popular over the last few years, for obvious reasons — who wouldn’t want to avoid period accidents?
Generally considered a good thing despite their relatively high price (around $17-$50 per pair), period underwear has been in the news lately for a not-so-good reason. Some contain PFAS — a class of chemicals known as perfluoroalkyl and polyfluoroalkyl substances.
In particular, Thinx, the most well-known brand of period underwear, recently settled a $5 million lawsuit regarding the chemicals but said it was not an admission of guilt, adding that they "stand by the quality, efficacy and safety of our products."
“The lawsuit is related to how products were marketed, and was not about injuries or harm caused by the products,” Thinx said in an email to BuzzFeed News. “PFAS is not included in our product design and we continue to take measures to help ensure these substances are not added to our products.”
That said, this week, for the first time, the American Apparel and Footwear Association added PFAS to a reference list of banned and restricted chemicals and substances, including apparel, footwear, accessories, and home textile products. (States have different existing and drafts of PFAS regulations; some states, like Maine, require regulation and labeling of products with PFAS as of 2023, while states like California, New York, and Colorado don’t have regulations that go into effect until 2024-2025.) The European Union announced this week that it's considering banning PFAS, although that's tricky to do, considering that they are used in some ways that make them hard to replace.
Like all chemicals that are lurking in the environment and products in general, the amount of PFAS you’re exposed to matters in terms of whether they’re a real problem for your health, and some types might be riskier than others.
Here’s what to know about PFAS, where you can find them, and how or why you might want to avoid them.
What is PFAS?
PFAS is a large group of synthetic chemicals first created in the late 1930s that can resist heat, oil, stains, grease, and water. More than 9,000 PFAS chemicals have been identified in industry and consumer products.
They have been used in industrial, commercial, and consumer products, such as adhesives, building and construction materials, cleaning products, cosmetics and personal care items, and more. The chemicals can be used in a variety of products including non-stick cooking pans, water-resistant clothing, stain-resistant rugs, and fire-fighting foam.
As a result, PFAS from landfills, sewage and waste plants, military bases, airports, and textile mills end up in our environment, including water and air, and the CDC found that 97% of Americans have PFAS in their blood. PFAS are known as “forever chemicals” because they can stay in the body for long periods of time, taking nearly four years for levels in the body to decrease by half.
Because they are found everywhere — in our food, water, clothes, and even the air — it’s not surprising that they are also in pads, tampons, and period underwear, regardless of whether they’ve been added on purpose.
People are concerned about the potential health impact of PFAS. Given that these chemicals are so ubiquitous and there are so many of them, it’s hard to say what the health risks are. Studies suggest that at least some types of PFAS may alter metabolism, cause fertility issues, increase the risk of certain cancers, and reduce the ability for the immune system to fight infections; less is known about low-level exposure over time or if some are worse than others.
So, manufacturers and regulatory agencies removed two types of PFAS — perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) — from many products starting 20 years ago, when they were first detected in human blood.
As of December 2022, the US Environmental Protection Agency has removed 12 PFAS from the list of ingredients that are approved for use in pesticides and other products. However, companies that don’t intentionally use PFAS can still have chemicals in their products as a result of manufacturing, processing, packaging, and shipping.
Why are people concerned about period products?
Since PFAS are everywhere, you might be asking: Why are we concerned about period products right now?
The Thinx class action lawsuit got its start in 2020 when Sierra Magazine journalist Jessian Choy published a story about PFAS levels in period underwear that had been marketed as "organic." In 2022, the wellness blog Mamavation worked with the EPA and found that out of 23 period products, five products contained a reactive chemical, fluorine, which is a marker for PFAS. Some of the products on the list were organic tampon brands.
Additionally, 65% of period underwear products that were tested in 2021 and 2022 had detectable levels of fluorine, including those by Thinx and Knix. Out of the brands tested, only six had products that contained no levels of fluorine, including Lilova, Aisle, Bambody, Intimate Portal, The Period Company, Modibodi, and Revol Cares.
Since then, Thinx and Knix say they have addressed PFAS in their products, and that they are taking additional steps to remove PFAS from manufacturing and testing their products.
“We conduct regular testing for PFAS, and we have never intentionally added them to our products,” Knix said in an email to BuzzFeed News. “You can see sample test results and read more about our testing here.”
Some companies may not be intentionally adding PFAS into their products or adding it to their designs. Since the chemicals can be found everywhere, they can make their way onto clothing through its manufacturing process, or come in contact with PFAS through packaging or shipping. Companies that use PFAS intentionally might add the chemical for stain or water-resistant use.
“One of the companies was using PFAS on the inner side of the underwear, which is really an odd place to use it,” said Graham Peaslee, professor and PFAS researcher at the University of Notre Dame, adding that it might be a water- or stain-resistant feature of the underwear. “In addition, it was touching the surface skin. The three areas of the body where the skin is thinnest is the neck, underarms, and the groin. That’s where you’re more likely to have dermal absorption. If there is a chemical, it can go through the skin layer.” (Peaslee conducted the testing included in Choy's reporting.)
How PFAS may affect the body
Research on PFAS is still limited, specifically the effects on the reproductive system.
However, researchers know quite a bit about the chemicals, and the news is mostly not good, said Dr. Alan Ducatman, a PFAS researcher and professor emeritus at the West Virginia University School of Public Health who is also board certified in internal medicine and in occupational medicine. “PFAS will be a problem, but there is little research. Federal agencies are trying to come up with predictive screening tests that may guide the discussion.”
The kidney is considered a target tissue of PFAS, with outcomes such as reduced kidney function, chronic kidney disease, and kidney cancer.
Exposure to PFAS also increases a person’s susceptibility to metabolic syndrome, a group of disorders including obesity, elevated blood pressure and cholesterol or fat levels, and impaired glucose tolerance. And PFAS studies indicate that high levels may decrease how well the body responds to vaccines, reducing antibody production.
Exposure to environmental contaminants, including drinking from contaminated water supplies, may cause susceptibility to long-term conditions like endometriosis, fibroids, genital tract and breast cancers, and decreased fertility.
Parents can transfer PFAS to a child during pregnancy and breastfeeding.
“When a woman is pregnant, her PFAS goes down,” Ducatman said. “That sounds good but it isn't. One of the places that the PFAS compounds are going is transplacentally to the developing human. Similarly, doctors and other health professionals recommend breastfeeding for good reasons. Breast milk is a source of PFAS, and parents from the most contaminated communities are concerned about this. The stress on parents is something I have heard from mothers quite frequently.”
How to tell if products have PFAS
Period products may carry a label that says PFOA-free or a PFOS-free, even if there are other types of PFAS in the product, Ducatman says.
“The FDA regulates some things, and not others,” he said. “One of the many things they do not regulate is the term ‘organic’ on food labels, as I understand it. Very recently, USDA announced its intention to do better with the organic label, and it was the Organic Trade Association that asked them to do it. Labeling is a big problem, and the label PFOA-free is an example. It is a tipoff that there is some other PFAS.”
According to the FDA, tampons, pads, and personal lubricants are considered medical devices, and some components are regulated. However, companies do not necessarily need to disclose chemical compounds on their packaging, although that’s starting to change.
Peaslee told BuzzFeed News that he provides tests for companies who want to see if their products are PFAS-free. Many companies that were tested did not know their products contained PFAS, and some said they were listed as PFAS-free on the company’s website even though they contained them.
“Companies will say, ‘We don’t use them [PFAS] and if we did use them, we use the safe kinds.’ Well, there are no safe kinds,” Peaslee said. “There’s alternatives and this is where the underwear is a classic example of what a company can or can’t do.”
Consumers can check descriptions on company websites or labels to get some clue about whether the product contains PFAS or other chemicals.
“If it has a property of being water-resistant or oil-resistant, those would be properties that belong to PFAS,” Peaslee said. “They often advertise that way, but none of the labels tell you that they use PFAS. That’s what we’re trying to fix.”
Additionally, the EWG provides a list of products that don’t intentionally contain PFAS chemicals that are water-resistant, including food packaging, building supplies, textiles and apparel, repellents, cosmetic products, and cookware.
Researchers are advocating for more legislation about PFAS and reducing the number of products that contain them and finding alternatives, or are substitutable, to non-essential uses. The essential uses are products that do not have an alternative to using PFAS. These are things that are nice to have, but aren't considered essential, such as non-stick pans, while essential uses have no alternatives, such as medical devices and pharmaceuticals.
“If you have a choice to not use this, then why are we using it? They [PFAS] are very functional and very good at what they do, but they can be alternatives that don’t involve the ‘forever chemical’ ones,” Peaslee said. “We’d like to get rid of them, except for essential uses.” ●