PFAS ‘Forever Chemicals’ Are Turning Up in Menstrual Products. Here’s What You Need to Know

Feminine hygiene products may be among the most basic and essential purchases a consumer can make. The 72 million women and girls in the U.S. of child bearing age—broadly defined as ages 15 to 49—rely on industry to provide them a diverse range of sanitary products, from tampons to pads to period underwear to liners, and industry generally responds. But increasingly it seems that manufacturers are delivering these consumers a very bad thing as well—one that can pose a grave threat to their health and welfare.

Over the past three years, feminine hygiene products have been turning up contaminated by PFAS, short for per- and polyfluoroalkyl substances. Also known as “forever chemicals,” these ubiquitous and persistent manufacturing chemicals have been linked by the U.S. Environmental Protection Agency (EPA) to a range of health ills, including: decreased fertility, high blood pressure in pregnant people, increased risk of certain cancers, developmental delays and low birthweight in children, hormonal disruption, high cholesterol, reduced effectiveness of the immune system—leading to decreased efficacy of vaccines—and more.

PFAS are found nearly everywhere, including our tap water—at least in communities that screen water for PFAS; soil near contaminated manufacturing sites; certain foods and food packaging; some household cleaning products; makeup, shampoo, and other personal care products; fire-fighting foam; and carpets. But it’s the presence of the chemicals in menstrual products that is causing the most stir of late, not least because of the close contact the items make to women’s bodies and the fact that so many of them are advertised as “natural” or “organic.”

In a series of lab analyses commissioned between 2020 and 2022 by the consumer watchdog site Mamavation and Environmental Health News, 48% of sanitary pads, incontinence pads, and panty liners tested were found to contain PFAS, as were 22% of tampons and 65% of period underwear.

What’s more, says Leah Segedie, founder and editor of Mamavation, in one of the analyses, out of the 22 products that tested positive for PFAS, “13 of them were advertised as ‘organic,’ ‘natural,’ ‘non-toxic,’ ‘sustainable,’ or using ‘no harmful chemicals.’” In another analysis, 13 of 18 products that made similar claims tested positive for PFAS.

The new investigations have spurred calls not only for better monitoring of all products for the presence of PFAS, but for tighter regulation—and eventual elimination of the chemicals entirely. Activists are leaning on manufacturers to find replacements for PFAS; manufacturers are pushing back, arguing that in some cases they’re not even aware that the substances are in their products, or that if they are present, they are in quantities so low that they could not cause harm.

It’s not just watchdog groups that are on top of the PFAS flight. Both the EPA and the White House have recently pledged action that includes the slow phasing out of PFAS as well as remediation and cleanup of contaminated sites. Meanwhile, from 2020 to 2022, three different class action suits—in California, Massachusetts, and New York—were filed against Thinx, a manufacturer of period underwear, alleging tests showing the presence of PFAS in its products. Thinx, which advertises its products as “sustainable” and “eco-friendly,” refutes all of the claims in the lawsuit. Nonetheless, in August 2022, the cases were consolidated in the Southern District of New York, and in December a settlement was reached, which offered women who purchased Thinx products the opportunity to submit for a refund or a voucher for a future purchase.

“In addition to that,” says Erin Ruben, one of the court-appointed attorneys representing the class, “there’s also some non-monetary relief, [involving] the measures [Thinx] will take to ensure that PFAS are not intentionally added to the underwear at any stage of production.” The company agreed in the body of the settlement document not only to ensure that PFAS are not deliberately used in any stage of the production process, but also to have their suppliers of raw materials sign a code of conduct attesting that they are taking similar preventive measures.

Thinx accepted the settlement while denying charges that it had included PFAS in its product deliberately and arguing that none of the plaintiffs in the suit had suffered injury.

But if one class action suit has been settled, the problem of PFAS—in menstrual products in particular and the environment in general—is not going away anytime soon. The chemicals are everywhere and in everyone—even in unborn babies, reached through the placenta, and in newborns contaminated with breast milk. It is a problem of our making, and it may be one that defies our best solutions.

What Are PFAS?

PFAS are not a single chemical but a family of roughly 12,000 of them. First developed in the 1940s, they have a range of uses, including making pots and pans non-stick; textiles more durable and stain resistant; food packaging resistant to grease; and paper and cardboard stronger. The substances are colloquially called “forever chemicals,” because, given their extraordinary durability, that’s pretty much how long they last in the environment—and not just the environment.

“They’re very persistent,” says Erin Bell, professor at the school of public health at the University of Albany. PFAS have a very long half life—or the amount of time it takes for the concentration of a chemical in the body or the environment to drop by half, and then by half of that half, and so on until there are only trace amounts left. “They take a very long time to leave our bodies.” According to the U.S. Centers for Disease Control and Prevention, the half-life for PFOS, one of the two most common types of PFAS, is 4.8 years in the body; for PFOA, the other most common type, it’s 3.5 years. In either case, that’s more than enough time for them to foment long-term health problems.

Worse, it doesn’t take a very high dose of PFAS to cause harm. PFAS do their greatest potential damage when they’re ingested. In June 2022, the EPA revised its guidelines for PFAS in water supplies, setting the safe threshold at just 0.02 parts per trillion (ppt) for PFOS, and 0.004 ppt for PFOA. (The concentration of PFAS in water supplies nationwide is unknown, since the EPA does not mandate universal testing.) The reason for setting such exceedingly low concentrations for a single dose of contaminated water is because the risk involves long-term, repeated exposure.

“It assumes you have a lifetime of drinking water,” says Graham Peaslee, professor of physics at the University of Notre Dame, who is also active in PFAS research and whose lab conducts regular tests of products for the substances. As he pithily notes, “when you’re alive, you drink water.”

Lab researchers don’t generally test for PFAS directly—which involves a very precise and pricey analysis—but rather for organic fluorine, which is found in the presence of PFAS and is easier to detect. A positive result for fluorine is considered a presumptive indicator that PFAS are there as well. “High total fluorine signals have always been PFAS,” says Peaslee.

The concentrations found in feminine hygiene products tend to be much higher than those permitted in tap water, and while they are not ingested the way water is, they are potentially just as dangerous since the vaginal area is exceedingly vascularized, making it more vulnerable to contaminants.

“It is a highly sensitive tissue,” says Bell. “So where we haven’t seen much in the way of transdermal exposure, say on the skin on the arm, in the vaginal area there is that potential.”

The tests run by Mamavation and the EHN found that PFAS levels in tampons ranged from 19 to 28 parts per million (ppm) in five of the 23 studied brands. In the 48% of sanitary and incontinence pads that tested positive, levels ranged from 11 to 154 ppm.

“What’s not yet known for these products is how much is in the products and how much actually gets into our bodies,” says Bell. An equally great worry is how such products affect workers in the plants manufacturing them, who may be exposed to heavy ambient PFAS concentrations and may be inhaling them or otherwise ingesting them when they alight on lips, hands, or food.

Trying to Fix the Problem

The U.S. federal government and manufacturers have not been entirely oblivious to the PFAS problem and lately have taken a somewhat more proactive approach. As long ago as 2002, companies under pressure from the EPA began agreeing to phase out PFOS in all products, followed by PFOA in 2015. But their presence, as forever chemicals, nonetheless lingers in the environment and in durable products produced before the ban.

Further, they were replaced by two other types of PFAS known as PFBS and GenX chemicals. Both were thought to be safer than PFOA and PFOS because they do not persist in the body as long, but both, says Bell, “have the potential to lead to some of the same health outcomes” as other PFAS. And while period products do not have PFOA or PFOS, they do test positive for fluorine, which suggests some other PFAS chemical is being used in their manufacture.

On Oct. 21, 2021, EPA Administrator Michael Regan announced an agency-wide “strategic roadmap” to restrict the use of PFAS and hold polluters accountable. The policy was a worthy sounding one, but its brief timeline—2021 to 2024—is too short to tackle a very big problem, and nobody pretends cleanup will happen by the end of next year. More realistically, in Dec. 2021, President Joe Biden signed an executive order that included a more modest “buy clean” provision that would see the federal government phasing out the purchase of any products that contain PFAS by 2050.

For now, the response to the discovery of PFAS in menstrual products has been limited. The government has not weighed in on the findings, and while consumers may have read the news and decided to avoid certain brands that were called out by Mamavation and the EHN, there have been no organized boycotts.

In menstrual products, PFAS help make the material more absorbent and, in the case of period underwear, more stain-resistant. Removing the PFAS and replacing them with less toxic substances that do the same job should be comparatively easy. The problem is, companies themselves sometimes do not even know they are using PFAS in their manufacturing process; the chemicals seem to be used in producing the raw materials they buy from suppliers.

The clue to inadvertent PFAS inclusion is in the concentration of the chemicals that are found in the products. When quantities are in the handful of parts per million or lower, Peaslee says, that usually indicates the manufacturer might not even know the PFAS are present, since levels so low do not have any impact on the function or effectiveness of the product.

Deliberate inclusion is a different matter. “What we typically find is hundreds or thousands of parts per million,” Peaslee says. That’s high enough to suggest that the final manufacturer included them intentionally. Unfortunately, he adds, “there’s no regulatory limit on that.”

Until enforceable regulations are imposed and industry comes up with safe, nontoxic replacements for PFAS, the chemicals will continue to be both ubiquitous and dangerous. Turning to the legal system, as in the case against Thinx, may be a poor, after-the-fact solution, but one that can at least force the manufacturers’ hands.

Meanwhile, women concerned about menstrual and other hygiene products do not have a lot of options short of consulting sites like Mamavation, EHN, and the Sierra Club, which also conducted a study of PFAS in period products, for those brands that tested free of the chemicals. The federal government currently does not require the industry to label its products for their PFAS content, though in 2019, New York state passed a law requiring companies to list all substances deliberately added to period products and in 2020, California followed suit. Until Washington does the same, most women will be left guessing, rolling the dice about one of the most important—and personal—consumer decisions they can make.