Safe Menstrual Products: What Testing Has Found in Tampons, Pads and Period Underwear

Key Takeaways

• Independent testing has now found metals, PFAS, phthalates and fragrance compounds across every category of menstrual product, including items marketed as organic.
• Vaginal tissue absorbs compounds directly into circulation without first passing through the liver, which makes this exposure route different from skin contact elsewhere on the body.
• A 2024 study from Columbia, UC Berkeley and Michigan State measured 16 metals in 30 tampons and detected lead in every single one.
• The FDA published its own follow-up in 2026 concluding the released amounts fall within its safety margins. That assessment rests partly on modeling work authored by a tampon manufacturer.
• Period underwear and reusable pads showed the highest rates of intentional PFAS use of any product category tested.
• Ingredient labeling is not required on menstrual products in the United States, so material disclosure and third party testing are the only tools a buyer has.

Medical disclaimer: This article is for educational purposes only and is not medical advice, diagnosis or treatment. Nothing here has been evaluated by any regulatory agency. Please speak with a qualified healthcare provider before changing anything about your health routine, and do not stop a prescribed medication or remove a medical device based on something you read online.

As an Amazon Associate I earn from qualifying purchases. Affiliate links in this article are labeled where they appear, and they cost you nothing extra.

What testing has found Why the exposure route matters What I use Cups and discs Period underwear IUDs and hormonal birth control How to choose FAQ

Most women will use menstrual products for close to forty years, several days a month, against tissue that absorbs compounds far more efficiently than the skin on an arm. Until recently there was almost nothing published about what those products are made of. That has changed over the past three years, and the findings are worth sitting with.

I want to walk through what the testing actually shows, because the coverage has swung between alarm and dismissal without much in between. Some of the concern is well supported. Some of the reassurance comes from parties with a stake in the answer. Both of those things can be true at once.

What testing has actually found

Metals in tampons

In 2024, researchers from Columbia University, UC Berkeley and Michigan State published the first study to measure metal content in tampons. They analyzed 30 tampons from 14 brands and 18 product lines for 16 metals and metalloids, and found measurable concentrations of all 16 across the sample set. Lead turned up in every tampon tested.

The geometric mean concentrations were 120 nanograms per gram for lead, 6.74 for cadmium and 2.56 for arsenic. Concentrations varied by where the product was bought, by organic status and by whether it was a store brand or a name brand. Lead ran higher in non-organic tampons. Arsenic ran higher in the organic ones, which the lead author attributed in part to those products being made entirely of cotton.

The authors were careful about what their method could and could not tell them. They measured total metal content using microwave acid digestion, which dissolves the product completely. That number tells you what is present. It does not tell you how much comes out of a tampon during eight hours of ordinary use, and the authors said so directly, calling for leaching studies as the necessary next step.

Shearston JA, et al. Tampons as a source of exposure to metal(loid)s. Environment International, 2024. PubMed 38963987

The follow-up work, and how to read it

The 2024 study prompted a congressional letter and an FDA response. The agency commissioned an independent literature review and ran its own bench study. That work was published in Toxicological Sciences in May 2026.

FDA researchers tested 11 tampon products for 21 metals using two methods. The first was the same acid digestion approach, and their content figures broadly matched the Columbia numbers. The second was an extraction study designed to estimate how much metal actually comes out: whole tampons soaked in acidified water at 50 degrees Celsius for 24 hours, conditions chosen to release more than normal use would. Released amounts came out four to a hundred times lower than the digestion figures.

They then built a risk assessment on top of that, assuming every released metal was fully absorbed, assuming six tampons a day for seven days a month across 38 years, and using the lowest plausible body weight. Margins of safety ranged from 7 to 2,017, with the lowest values for antimony at 7, lead at 8 and calcium at 9. Their conclusion was negligible toxicological concern.

Where I would be careful

Three things about this deserve flagging. The study was conducted by the agency that regulates tampons as Class II medical devices, which means it is evaluating a category it is responsible for. Its discussion of why lead absorption is likely lower than assumed leans on a 2026 modeling paper estimating that under 0.5 percent of released lead would be taken up, and the authors of that paper are at Procter and Gamble, which owns Tampax. And the assessment evaluated each metal on its own, stating plainly that a cumulative analysis of the mixture was outside its scope.

None of that makes the findings wrong. Exaggerated extraction is a legitimate method and the conservatism built into the exposure assumptions is real. It does mean the two pieces of evidence pushing toward reassurance are not independent of the parties who benefit from that conclusion, and that a margin of safety of 7 or 8 is a thinner cushion than it sounds when the exposure runs for four decades.

What survives all of it is the Columbia finding itself. The metals are in the products. The disagreement is about how much crosses over.

Source: The Guardian

PFAS in period products

Graham Peaslee's lab at Notre Dame has been screening menstrual products for total organic fluorine since 2019, using a technique that fires a proton beam at a sample and measures the gamma rays that fluorine nuclei emit in response. High total fluorine is a strong presumptive marker for PFAS, the class of persistent compounds used to make textiles repel water and oil.

The first result came from a 2020 Sierra Club investigation. A reporter mailed unused Thinx organic briefs to Peaslee, and the crotch layer came back at 3,264 parts per million fluorine. A version marketed to teens measured 2,053 ppm. A competing brand tested at the same time showed none. Levels that high indicate deliberate treatment rather than stray contamination. Litigation followed and consolidated into a class action that Thinx settled for five million dollars in 2023 without admitting wrongdoing.

A broader screen followed. Peaslee and graduate student Alyssa Wicks tested more than 100 single-use and reusable products, sampling each layer separately, and reported that tampons, menstrual cups and the pad layers that touch skin generally came back clean. The fluorine concentrated somewhere less expected: the wrappers on many pads and some tampons, and the outer layers of some period underwear, several of which measured in the thousands of parts per million.

Their largest study appeared in Environmental Science and Technology Letters in July 2025. Wicks tested 59 reusable products across four continents, breaking them into 323 individual layer samples. Most of what she measured, 71.2 percent, sat low enough to be classified as unintentional fluorination. The exceptions clustered in two categories: 33 percent of period underwear and 25 percent of reusable pads showed levels consistent with PFAS being deliberately applied during manufacture.

Wicks made a point in that paper worth repeating, because it changes what a consumer can reasonably ask for. Only a subset of products used PFAS, which demonstrates the chemistry is not necessary to make waterproof reusable textiles. Manufacturers who use it are choosing to.

Wicks A, et al. Environmental Science and Technology Letters, 2025. DOI 10.1021/acs.estlett.5c00553. Separately, lab work commissioned between 2020 and 2022 by Mamavation and Environmental Health News found PFAS indicators in 48 percent of pads, liners and incontinence pads, 22 percent of tampons and 65 percent of period underwear tested.

Phthalates, fragrance and plastic additives

The most methodologically useful study on this question came out of Belgium in 2025, from researchers at Sciensano and Vrije Universiteit Brussel. Rather than asking only what is present, they built a three-step workflow that asks what actually comes out.

They tested 64 products sourced from the EU, US and China, covering tampons, sanitary napkins, menstrual cups, Kegel devices and menstrual sea sponges. Exhaustive extraction identified 55 unique chemicals, including phthalates, siloxanes, volatile organic compounds, fragrance materials and plastic additives. They then ran migration experiments using simulated vaginal and menstrual fluid at realistic wear times.

Of those 55 compounds, 36 did not migrate at all. Nineteen did: nine fragrance materials, five phthalates, two plastic additives and three VOCs. Peak measured levels were 28.22 micrograms per gram for heliotropine, 100 parts per billion for DEHP and 18 parts per million for triethyl citrate. On the metals side, menstrual sea sponges leached the most of any category by a wide margin, with nickel reaching 1,850 ppm.

That result cuts in both directions and I think it should be reported as such. Two thirds of what a solvent can pull out of a product never reaches the body under realistic conditions, which argues against reading every content study as an exposure study. The remaining third does reach the body, and DEHP and several of those fragrance compounds are well characterized endocrine disruptors and sensitizers.

Marcelis Q, et al. Chemical characterization of menstrual and intimate care products: an extractables and leachables investigation. Environment International, 2025. PubMed 40239564

Why the exposure route matters

Vaginal tissue is thin, densely vascularized and lacks the keratinized barrier that makes forearm skin a reasonably good shield. Anything absorbed there enters systemic circulation directly, bypassing the first-pass liver metabolism that breaks down a large share of what we swallow. This is the same property that makes vaginal drug delivery effective for medications, and it is why the researchers who found metals in tampons flagged the insertion route as the more concerning one.

There are real counterweights. Menstrual fluid carries red blood cells, hemoglobin and metal-binding proteins that sequester a portion of anything released, which is the mechanism behind the estimate that under half a percent of released lead would actually be absorbed. Vaginal permeability also shifts across the cycle and drops at the start of menstruation.

I find both of those plausible and neither of them settling. Binding proteins reduce absorption without eliminating it, the magnitude of that reduction has been estimated for lead and not measured for most other metals, and the products sit against mucous membrane for several days a month across four decades. My position is that the burden of proof should sit with the manufacturer, and at present nobody has to meet it.

The regulatory gap is the part I find most difficult to defend. Menstrual products are regulated as Class II medical devices in the United States, which governs absorbency labeling and manufacturing but does not require ingredient disclosure. There is no obligation to list what a pad is made of, no PFAS labeling requirement in most states and no mechanism forcing a brand to tell you whether it treats its textiles. A woman who wants to make an informed choice is dependent on whichever companies decide to volunteer the information.

What I use for my cycle

I use Natracare, and I want to be precise about why, including where their marketing language is looser than their materials.

Their tampons are 100 percent certified organic cotton with no rayon or viscose. Their pads are not entirely organic cotton, and I see this stated incorrectly all over the internet. The layer against your skin is GOTS certified organic cotton. The absorbent core underneath is mechanically processed wood pulp from FSC certified Scandinavian pine, held together with plant starch and BPA-free medical-grade adhesive. Their published figure is over 95 percent biodegradable, not fully biodegradable.

The cotton and pulp are bleached, which is another claim I see rounded off. Natracare uses a Totally Chlorine Free process rather than the Elemental Chlorine Free method common in conventional products, and ECF does still involve chlorine compounds. TCF is the meaningfully better process, and it is not the same as unbleached.

Here is what I think the accurate version of their materials list looks like:

• Organic cotton certified to GOTS standard on the surface layer of pads, and throughout the tampons
• No plastic in the product or the wrapper, including no polyethylene backing and no polyacrylate superabsorbent
• Totally Chlorine Free bleaching rather than chlorine dioxide
• No synthetic fragrance, no dyes, no latex, no surfactants or binders
• Individually wrapped in cellulose rather than plastic film
• Commercially compostable to EN 13432 and ASTM D6400

That last point about the wrapper matters more than it sounds, given that plastic film wrappers were where the Notre Dame screening found some of its highest fluorine readings. I cannot tell you Natracare tested clean, because neither the Columbia nor the Notre Dame teams disclosed brand names. What I can tell you is which materials the company declares, and that a cellulose wrapper avoids the specific material that came back loaded in that screen.

One limitation worth stating on all of this: the Columbia data found arsenic running higher in the all-cotton organic tampons than in conventional ones, most likely reflecting what the cotton took up from soil and irrigation water. Organic certification governs what gets applied to a crop. It does not control what was already in the ground. Choosing organic cotton removes pesticide residue and synthetic processing chemistry from the equation, and it does not remove metals.

The products cost more. I have kept buying them anyway, partly for the materials and partly because plastic-free packaging is rare enough in this category that I would like the companies doing it to stay in business.

Menstrual cups and discs

Cups run roughly 25 to 40 dollars and last years with care, which makes them the cheapest option available over any reasonable time horizon. They also came out well in the fluorine screening, alongside tampons, as one of the categories that consistently showed no meaningful PFAS signal.

What we know and do not know about the silicone itself

Medical-grade platinum-cured silicone is a polysiloxane, built on a silicon and oxygen backbone rather than the carbon chains that make up petroleum plastics. That distinction gets used to end the conversation, and it should not.

Cured silicone is not a sealed material. It contains residual cyclic siloxane oligomers, and testing on silicone food contact products has found them migrating out. A 2025 analysis identified 25 distinct siloxane species across every silicone bakeware product tested, with quantifiable congeners totaling between 680 and 4,300 micrograms per gram of material. Migration is highest into fatty simulants and during the first several uses. Two of these compounds, D4 and D5, are listed by the European Chemicals Agency as very persistent and very bioaccumulative, and D4 carries a Substance of Very High Concern designation for endocrine activity. The Belgian extractables study found siloxanes among the compounds recoverable from products in this category.

Two further gaps matter as much as those findings. The heavier siloxane congeners have barely been assessed for toxicity at all, so a study reporting migration below regulatory thresholds is reporting on the fraction anyone has bothered to set a threshold for. And every analytical method has a detection floor, meaning particulate or degradation products below that floor are not measured as absent, they are not measured.

Why I do not treat silicone as settled

Materials introduced as inert have a track record of being reclassified once someone looks properly. PFOA in nonstick cookware was in kitchens for decades before the fluorochemistry was understood. Brominated flame retardants turned up in black plastic kitchen utensils because recycled electronics feedstock was going into them, and nobody was looking until 2024. Silicone menstrual cups and silicone cookware have been in wide use for a fraction of a human lifespan, and no cohort has been followed from first use to old age. Absence of long-term data is not evidence of safety. It is absence of data.

None of that makes cups a bad option. Their siloxane load is likely lower than heated cookware, since body temperature is far below the conditions that drive migration, and boiling for sterilization is brief and intermittent. What I object to is the confident language, not the product.

IUD expulsion

This concern is better documented than most people realize. A 2023 systematic review in Contraception and Reproductive Medicine pulled together seven studies covering 73 partial or total expulsion events among cup users with IUDs, with reported expulsion rates of 3.7, 17.3 and 18.6 percent depending on the study. A 2019 survey found concurrent cup use associated with roughly 2.75 times the odds of expulsion, with no such association for tampons or pads.

The most striking evidence came out of a randomized copper IUD trial. About twelve months into enrollment, investigators began advising participants against menstrual cups because of the expulsions they were seeing. In the preliminary data, 18 percent of the 277 women reporting cup use experienced expulsion, against 6 percent of the 704 reporting tampon use. If you have an IUD, this is worth raising with whoever placed it.

Toxic shock syndrome

Documented and rare. The 2019 Lancet Public Health review of 43 studies found five case reports in the literature, and menstrual TSS overall runs between 0.03 and 0.50 cases per 100,000 people with roughly 8 percent mortality. Cups are not exempt from wear-time limits simply because they are not absorbent.

I use organic cotton pads because cups have never worked well for me, and I want to separate that from a safety claim. The evidence does not support calling cups dangerous. It also does not support calling them proven.

Period underwear

This is the category where the testing looks worst, and it is the one most heavily marketed to health-conscious buyers.

Waterproofing a fabric layer is the whole function of the product, and PFAS is the cheapest chemistry that does it. That is the mechanism behind the 33 percent intentional fluorination rate in the 2025 study, and behind the Thinx results before it. Wicks noted that some of the products she tested had as many as ten distinct layers, which means a brand can source a treated membrane without ever handling the treatment itself.

If you want to use period underwear, this is the standard I would hold a brand to:

• Published third party test results for total organic fluorine, not a statement that the brand does not add PFAS. Those are different claims, and the second one is compatible with buying a pre-treated membrane.
• A stated waterproofing method. Polyurethane laminate is not PFAS, and a brand using it should be willing to say so.
• Certified organic cotton on the layer against skin, with the dye process disclosed. Many textile dyes are fixed using mordants containing heavy metals.
• Full layer-by-layer material disclosure rather than a single line about the outer fabric.

I have not found a brand that meets all four, which is why I do not use these. If you know of one that publishes its fluorine testing, please leave it in the comments so the rest of us can look at it.

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How to choose, given what we know

There is no product on the market that testing has cleared completely, so this is a matter of reducing what you can control rather than finding a perfect answer.

1. Skip anything scented. Fragrance materials were the largest group of compounds that actually migrated in the Belgian leaching study. Most US manufacturers have already discontinued scented tampons, and scented pads, liners and intimate washes are still widely sold.
2. Prefer cotton over rayon and viscose. Rayon is wood pulp put through chemical conversion, and the FDA testing found rayon-based products carrying higher barium, lithium and zinc than the cotton-based ones.
3. Look at the wrapper, not only the product. Plastic film wrappers were where the Notre Dame screening found several of its highest fluorine readings. Paper and cellulose wrapping avoids that material.
4. Treat period underwear as the category needing the most scrutiny. Ask for published total fluorine testing before you buy, and treat silence as an answer.
5. Respect the eight hour limit regardless of product. This applies to cups as much as tampons, and overnight tampon use is specifically advised against.
6. Ask brands directly. Peaslee's suggested question is the right one: does this product contain any intentional use of PFAS? A company that will not answer in writing has told you something.

Final thoughts

Fertility has been declining across industrialized countries for decades, and endocrine-disrupting chemical exposure is one of the more compelling explanations on the table. Dr. Shanna Swan's book Countdown lays out that argument, including the work on anogenital distance, the measurement from the anus to the base of the genitals that reflects prenatal androgen exposure and correlates with adult sperm count in men. Countdown by Dr. Shanna Swan (affiliate link) is worth reading if this is new to you.

I would not claim menstrual products are the main driver of that trend. Diet, plastic food packaging, drinking water and household dust all deliver larger cumulative exposures for most people. What makes period products worth singling out is the combination of an unusually absorptive tissue, a duration measured in decades and a regulatory regime that requires no ingredient disclosure whatsoever. It is a category where a person could make a better choice if the information existed, and mostly it does not.

It is also a category where the pattern of discovery keeps repeating. A material goes into wide use, the safety question goes unasked for twenty or thirty years because nobody is required to ask it, and then somebody finally runs the test. That is what happened with the metals in tampons, which nobody had measured until 2024. It is what happened with PFAS in period underwear, which surfaced because a magazine reporter mailed a pair to a physicist. Neither of those findings came from the regulatory process.

I used conventional pads all through high school without a thought about what was in them. Many of my friends are at the age now where they are trying to start families and finding it harder than they expected. I cannot draw a line from one to the other and I am not going to pretend I can. I can say that the questions are reasonable, the testing is finally being done and the answers keep arriving later than the products.

If there are young women in your family or your circle, the conversation worth having is not a frightening one. It is about reading a materials list, asking a company a direct question and understanding that the absence of a warning label is not the same as the presence of safety data.

Frequently asked questions

Are tampons safe to use?

Testing has found trace metals in every tampon studied, including lead. The FDA's 2026 risk assessment concluded the amounts that actually release during use fall within its safety margins, though that assessment was produced by the agency that regulates the product and relies partly on modeling from a tampon manufacturer. Independent researchers have called for more leaching data. Choosing organic cotton removes pesticide residue and synthetic processing chemistry, and does not remove metals.

Do period products contain PFAS?

Some do. In the largest study to date, 71 percent of reusable product samples showed fluorine low enough to be considered incidental contamination. Period underwear at 33 percent and reusable pads at 25 percent showed levels consistent with deliberate PFAS treatment. Tampons, menstrual cups and the skin-contact layers of pads generally came back clean, while plastic wrappers frequently did not.

Which menstrual products are safest?

No product has been cleared completely. The lowest-exposure options based on current testing are unscented certified organic cotton tampons and pads with paper or cellulose wrapping. Scented products and period underwear without published fluorine testing carry the most documented concern.

Is silicone safe for menstrual cups?

Medical-grade platinum-cured silicone is chemically distinct from petroleum plastics and holds up well at body temperature. It is not inert. Cured silicone contains residual cyclic siloxanes that migrate out under testing, two of which are classified in the EU as very persistent and very bioaccumulative, and the heavier siloxane compounds have barely been assessed for toxicity. No population has been followed across a lifetime of use.

Can a menstrual cup dislodge an IUD?

Yes, and the association is well documented. A systematic review found expulsion rates ranging from 3.7 to 18.6 percent among cup users with IUDs, and a randomized copper IUD trial recorded 18 percent expulsion among cup users compared with 6 percent among tampon users. Investigators in that trial began advising participants against cup use partway through enrollment.

Is organic cotton better for period products?

For pesticide residue, synthetic processing chemistry and plastic content, yes. For metals, not necessarily. The 2024 tampon study found lead running higher in non-organic products and arsenic running higher in the all-organic-cotton ones, since organic certification governs what is applied to a crop rather than what is already present in soil and irrigation water.

What chemicals actually leach out of period products during use?

A 2025 Belgian study tested 64 products using simulated vaginal and menstrual fluid at realistic wear times. Of 55 compounds recoverable by exhaustive extraction, 36 did not migrate at all. The 19 that did comprised nine fragrance materials, five phthalates, two plastic additives and three volatile organic compounds. Menstrual sea sponges leached far more metal than any other category tested.

Why are menstrual products not required to list ingredients?

They are classified as Class II medical devices in the United States rather than as cosmetics, a category that regulates absorbency labeling and manufacturing practice without requiring ingredient disclosure. A handful of states have passed or drafted their own labeling and PFAS legislation, and there is no federal requirement.