The hormone disruptors hiding in period products

By Ruby Raut, founder and CEO, WUKA

When we think of period products, the usual concerns are comfort, absorbency, cost and maybe sustainability. But there is another dimension — one less talked about but increasingly evidenced: chemical exposure via intimate-use products, and what this might mean for hormones, fertility, our microbiome and long-term health.

What Are Endocrine Disruptors?

Endocrine-disrupting chemicals (EDCs) are substances that either mimic, block or interfere with the body’s natural hormones. These hormones regulate growth, development, reproduction, metabolism and more. Exposures to EDCs have been linked to irregular periods, early puberty, infertility, PCOS (polycystic ovary syndrome) and endometriosis, among other conditions.

Although most public conversation about EDCs centres on plastics, food packaging, and household chemicals, this issue is now being traced into period products too.

Why Period Products Are a Unique Exposure Route

The route of exposure matters — and for period products it matters a lot. External products like pads or period underwear sit on the skin; yes, there’s absorption, but the skin provides more of a barrier than the internal mucosal tissues of the vagina and vulva. When products are inserted (tampons, menstrual cups) or used intimately against highly vascular mucous membranes, chemical absorption can be 10–80 times higher than skin contact.

This means that a small amount of a problematic chemical in a tampon or reusable underwear could result in a greater internal dose than a similar substance used externally. Moreover, because the vaginal route can bypass the liver’s first-pass metabolism, the body’s defences are fewer — increasing the potential for impact.

What Research Is Finding

Recent reviews of menstrual product testing reveal worrying patterns:

• A systematic review found that menstrual products (tampons, pads, liners) contained a variety of EDCs including phthalates, parabens, volatile organic compounds, dioxins and dioxin-like compounds.
  
• Studies of PFAS (per- and polyfluoroalkyl substances) — the so-called “forever chemicals” — show these synthetic compounds are endocrine disruptors and are increasingly linked to fertility challenges, PCOS, early puberty, and other hormone-mediated outcomes.
  
• For example, one S. study found higher PFAS levels among women seeking fertility treatment and a link to increased PCOS risk.
  
• Another study found that many reusable period products had high levels of PFAS, even though PFAS aren’t strictly necessary for functionality — meaning the exposures are avoidable.
  

What Does That Mean for You?

It’s tempting to read these findings and feel overwhelmed. Yes, we live in a chemically complex world — from pollution in the air to additives in food — but what makes this different is frequency of use, intimate contact, and cumulative exposure.

Think of it like this: someone might use a tampon (or other internal product) many times a month, for decades. The small dose of an EDC each time may be low, but over time it adds up — especially if it bypasses detox filters and steadily influences hormone networks.

That’s why brands and regulators need to shift from “Is there some chemical present?” to “What is the dose, for how long, by what route?” — and what that means for human biology over years.

Steps Towards Better Protection

1. Ask about disclosure and testing: Brands should publish test reports and confirm they’ve checked for EDCs, PFAS, and reproductive-toxic chemicals.
2. Prefer products without unnecessary chemical finishes: For instance, water-repellent or “antimicrobial” coatings may add PFAS or biocides; research shows many products function fine without them.
   
3. Consider internal vs external product choices: While convenience and comfort matter, understanding how products are used helps you make informed decisions.
4. Advocate for regulation: Science is building, and policies are starting to reflect the risk. But consumers’ voices help accelerate change.

WUKA’s Commitment

At WUKA we believe that transparency and rigorous testing aren’t optional — they are essential. That’s why we test every period underwear batch (in China and again in the UK via Eurofins) to ensure no PFAS are detected and no known reproductive-toxic chemicals are present. If I wouldn’t use it myself, I wouldn’t make it for anyone else.

Looking Ahead

There’s still much we don’t know: the exact doses absorbed through vaginal tissues, how mixtures of chemicals interact in the body, or the long-term impact of low-level exposures. But that’s all the more reason to act now rather than wait. EDCs affect not just one body, but generations.

In the end, it’s about more than fear — it’s about empowerment. Knowing what is in the products we use gives us the power to insist on better safety, better transparency and better health. Because safe periods aren’t a luxury, they’re a basic human right.