Metals in Tampons: What the Berkeley and FDA Studies Found

In July 2024, a study published by researchers at the University of California, Berkeley, reporting the presence of metals in tampons attracted worldwide attention. Headlines quickly spread across the media, leaving many women wondering whether the tampons they use every month could pose a health risk.

This question matters to millions of women. In the United States, an estimated 52–86% of women regularly use tampons, and they are also widely used throughout Europe. We received numerous questions from our own customers after the study was published.

Two years later, another important study added valuable context. In 2026, scientists from the U.S. Food and Drug Administration (FDA) published research in the peer-reviewed journal Toxicological Sciences. Unlike the Berkeley study, the FDA researchers not only measured metals found in tampons but also evaluated whether these metals could realistically pose a health risk during normal tampon use.

In this article, we'll explain what both studies found, how they differ, and what I believe women should take away from the current scientific evidence.

Should Women Be Worried About Metals in Tampons?

The short answer is probably not – based on the evidence currently available.

The 2024 Berkeley study detected a variety of metals in different tampon brands, including very small amounts of heavy metals such as lead, cadmium, and arsenic. However, detecting a substance in a product does not automatically mean it enters the body in harmful amounts.

This is the key difference between the two studies.

The Berkeley researchers identified which metals were present in tampons, but they did not investigate how much of those metals could actually be released during use, absorbed through vaginal tissue, or whether they could affect human health.

The 2026 FDA study addressed exactly these questions. Researchers evaluated not only the concentrations of metals in tampons but also how much could potentially be released during use and what the maximum possible health risk would be under highly conservative assumptions.

Their conclusion was reassuring:

Based on current scientific evidence, the levels of metals detected in tampons are not expected to cause adverse health effects.

That doesn't mean the topic no longer deserves scientific attention. On the contrary, additional independent research will help improve our understanding even further.

However, compared with what we knew in 2024, we now have significantly stronger evidence to put the original findings into context.

What Did the 2024 UC Berkeley Study Find?

The 2024 study, published in Environmental International, investigated whether metals were present in tampons sold in the United States, the United Kingdom, and the European Union.

Researchers analyzed 24 tampon products representing 14 brands, 18 product lines, and five absorbency levels. Most samples (79%) were purchased in the United States, while the rest came from the UK and EU.

How Were the Tampons Tested?

Researchers used laboratory acids to completely break down the tampons and measure the total amount of metals present in the material.

Using this method, they detected various metals in all tampons tested, including small amounts of lead, arsenic, and cadmium, regardless of whether the products were marketed as organic or conventional.

The researchers suggested several possible sources of these metals, including:

• natural uptake from soil by cotton plants,
• environmental pollution,
• manufacturing processes,
• and additives such as ingredients used to improve insertion, control odor, or provide antimicrobial effects.

An Important Limitation

The Berkeley study identified which metals were present, but it did not investigate:

• how much of these metals could be released during tampon use,
• whether they could be absorbed through vaginal tissue,
• or whether they pose a health risk.

The authors acknowledged this limitation and recommended further research to evaluate actual exposure during normal tampon use.

That is exactly what the 2026 FDA study investigated.

What Did the 2026 FDA Study Add?

To better understand whether metals detected in tampons could actually affect women's health, FDA scientists analyzed 11 tampon products sold in the United States and performed both a chemical analysis and a toxicological risk assessment.

Unlike the Berkeley study, the FDA researchers evaluated:

• how much metal could be released during tampon use,
• how much could theoretically be absorbed by the body,
  
• nd whether these amounts could pose a health risk over time.

A Conservative "Worst-Case" Assessment

To avoid underestimating any potential risk, the researchers used conditions that were more extreme than real-life use.

Tampons were kept in an acidic solution (pH 5) for 24 hours at 50°C (122°F). In reality, body temperature is about 37°C (98.6°F), and tampons should be changed at least every 8 hours.

The researchers also assumed that 100% of the metals released would be absorbed by the body, even though actual absorption is expected to be much lower.

FDA's Conclusion

The FDA study found that although various metals can be detected in tampons, only a very small fraction is released during use.

Even under these highly conservative assumptions, the researchers concluded that the detected levels are not expected to pose a significant toxicological risk to women's health.

This doesn't mean research should stop. More independent studies will continue to improve our understanding of menstrual product safety.

However, compared with 2024, we now have stronger scientific evidence suggesting that the presence of trace metals in tampons does not appear to represent a meaningful health risk under normal conditions of use.

Are GENTLE DAY Tampons Safe?

Although we're almost certain GENTLE DAY tampons were not included in either study (our brand is not widely available in the U.S., where most samples were purchased), we'd like to explain the principles we follow when developing our products.

GENTLE DAY tampons are made from 100% GOTS-certified organic cotton. We do not use additional ingredients to improve insertion, control odor, or provide antimicrobial effects. Our goal is simple: keep the product composition as clean and transparent as possible.

Why GOTS Certification Matters

GOTS (Global Organic Textile Standard) is one of the world's most rigorous textile certifications. It covers the entire production process—from cotton farming to the finished product—and includes strict environmental, chemical, and social requirements.

The standard also sets limits for certain undesirable substances, including heavy metals. Our cotton is tested to meet these requirements, and GENTLE DAY tampons comply with GOTS limits.

It's also worth noting that the 2024 Berkeley study did not specify which organic certifications, if any, the tested tampons carried. Therefore, its findings cannot be used to draw conclusions about specific certification standards such as GOTS.

GENTLE DAY Perspective

At GENTLE DAY, we welcome independent research into menstrual product safety. The more high-quality scientific evidence becomes available, the better we can understand potential risks and continue improving the products women rely on every month.

We've always believed that feminine hygiene products should meet the highest possible quality and safety standards. Because some substances can be absorbed through vaginal tissue, we believe that product composition, raw materials, and manufacturing processes deserve particular attention.

That's why we've invested in independent certification and continuous quality control from the very beginning – even when regulations didn't require it.

In our view, it's worth paying attention not only to naturally occurring trace metals but also to ingredients intentionally added during manufacturing, such as fragrances, antimicrobial agents, or insertion aids.

This doesn't necessarily mean these ingredients are unsafe. However, we believe that the simpler and more transparent a product is, the better. That's why GENTLE DAY tampons are made from 100% GOTS-certified organic cotton, without added fragrances, antimicrobial agents, or insertion aids.

Which Tampons Should You Choose?

At GENTLE DAY, we've never encouraged women to use tampons as their primary menstrual product.

Many gynecologists point out that tampons absorb not only menstrual blood but also some of the vagina's natural moisture. For some women, this may contribute to vaginal dryness, discomfort, or an increased risk of irritation.

However, we also recognize that millions of women prefer tampons. That's why, in 2013, we introduced 100% GOTS-certified organic cotton tampons, offering a simpler and more transparent alternative.

Why Choose GENTLE DAY Tampons?

Our tampons are:

• made from 100% GOTS-certified organic cotton;
• hypoallergenic, helping reduce the risk of irritation and allergic reactions;
• free from added insertion aids, fragrances, and antimicrobial agents;
• made with our patented CottonLock® technology, where the absorbent cotton core is fully wrapped in an organic cotton veil to help reduce fiber shedding.

When choosing tampons, it's worth looking beyond marketing claims such as "organic cotton." Instead, check whether the product is independently certified according to internationally recognized standards, such as GOTS, and whether the manufacturer is transparent about the materials and ingredients used.

For many women, menstrual cups can also be an excellent alternative. Unlike tampons, they collect menstrual fluid rather than absorb it and can be reused for years.

Final Thoughts

The growing scientific interest in menstrual product safety is encouraging. The more high-quality, independent research becomes available, the better we can understand potential risks and continue improving the products women use every month.

Based on current evidence, the trace levels of metals found in tampons are not expected to pose a significant health risk. Ongoing research will continue to improve our understanding of tampon safety and help manufacturers maintain even higher quality standards.

When choosing tampons, look beyond marketing claims. Consider products with simple ingredient lists, independent certifications, and manufacturers that are open about their materials and production standards.

OUR TESTS & CERTIFICATES

At GENTLE DAY, we'll continue following new scientific evidence and doing our best to offer products that prioritize quality, transparency, and women's health.