PFAS Free Period Underwear
the headline
Researchers from the University of Notre Dame studied more than 120 different menstruation products (commissioned between 2020-2022 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. Although the researchers did not provide specific details, the study found that “a good fraction” of the period underwear products had detectable levels of PFAS in the lining.
what are PFAS?
PFAS are not a single chemical but a family of roughly 12,000 of them. They have a range of uses, including non-stick surfaces, durable textiles and stain resistant materials; and making food packaging resistant to grease.
They’re called “forever chemicals” because they last a long time in the body. The half-life for PFOS, one of the two most common types of PFAS, is 4.8 years in the body (more than enough time for them to cause long-term health problems)! So what are these problems?
why is this an issue?
PFAS have been linked by the U.S. EPA to a range of health concerns including: decreased fertility, high blood pressure in pregnancy, increased risk of cancer, developmental delays, low birthweight in children, hormonal disruption, high cholesterol and reduced effectiveness of the immune system.
why is period underwear a particular concern?
It doesn’t take a very high dose of PFAS to cause harm. PFAS do their greatest potential damage when they’re ingested.
The concentrations found in feminine hygiene products tend to be much higher than those permitted in tap water, and while they are not ingested like water, they are potentially just as dangerous since the vaginal area is incredibly vascularised, making it more vulnerable to contaminants.
what is period underwear made from?
inner layer: preferably organic cotton, bamboo or Tencel Modal
central absorbant layer: cotton , merino wool,
or polyester
Leak proof layer: PUL (Polyurethane laminate fabric) or modal, seaweed fiber, and elastane
outer layer: again preferably organic cotton, bamboo or Tencel Modal
what is PUL?
PUL is a polyester knit fabric that is laminated on one side with polyurethane. The unlaminated side wicks moisture and the laminated side is what makes our underwear leak proof. Most companies prefer to use this fabric instead of water resistant sprays and chemical treatments, which have a risk of containing PFAS toxins.
We don’t know how much PFAS the body absorbs from underwear, but a recent study showed that the absorption of PFAS through the skin is as harmful as when PFAS are ingested orally (source).
buyers tips
A company should be vocal about testing for fluorine in their product, so check their website, and if in doubt message them and ask!
Ideally you want to buy from a company who tests themselves and doesn’t rely on testing from suppliers.
A good safe guard is looking for OEKO-TEX® + GOTS (Global Organic Textile Standard) certification, which also ensure that no harmful chemicals are used in the processing or dyeing of the fibres and fabrics.
so where is the PFAS coming from then?
PFAS won’t be added intentionally, but period products testing positive for fluorine is suggestive of PFAS chemicals being used in their manufacturing process somewhere. More research needs to be done to determine where.
