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Tampon safety – what are the real risks?

In Community and Relationship, Women's Health by robert.verkerkLeave a Comment

In the wake of the latest warning that tampons might contain Monsanto’s herbicide Roundup, should menstruating women give up on tampons completely? How big of a risk is Toxic Shock Syndrome?

Staph infections or Roundup anyone?

If you use tampons, are you concerned about the risk of life-threatening Toxic Shock Syndrome (TSS) caused by the Staphylococcus aureus bacteria? It’s been a concern since the late 1970s, but last year a new risk was mooted: tampons could expose women to Monsanto’s herbicide glyphosate (Roundup®), itself recently upgraded by the International Agency for Research on Cancer (IARC) from a possible to a probable human carcinogen. Other risks have also been linked to tampon use, including exposure to dioxins and furans, highly toxic and potential cancer-inducing compounds associated with the chlorine-bleaching process used in the manufacture of some tampons.

Tampons: therapeutic devices

Tampons in most parts of the world, Australia included, are registered as medical (therapeutic) devices. The Therapeutic Goods Administration (TGA) in Australia lists tampons in a category called ‘Other Therapeutic Goods’ and requires that they are listed on the Australian Register of Therapeutic Goods (ARTG). That should make them safe, yes? Not necessarily.

So, what of the actual risks? Are these possible to determine?

Toxic Shock Syndrome risks

The good news for around the 70% of women who use tampons is that tampon-mediated TSS is very rare, occurring at an incidence of no more than 2 cases per 100,000 women. If you assume an average woman might use 9,120 tampons in her lifetime (one tampon every 6 hours = 4 tampons per day x 5 days of a period = 20 tampons per cycle x 456 periods = 9,120 tampons), this puts the theoretical risk of getting TSS from use of each tampon at about 1 in 500 million. A little less comforting is that you take this risk nearly 10,000 times in your lifetime assuming you’re a tampon-only woman.

Before we look more closely at last year’s hoo-hah about glyphosate, let’s dig a bit deeper into the TSS issue, because it’s still not well understood by many. That’s partially because back in the late 1970s and early 1980s when it first raised its head after Procter and Gamble’s Rely tampons were introduced to the market, scientists and doctors didn’t have a particularly good understanding of this most sensitive part of the woman’s anatomy into which the tampon is put to use.

Perfect storm

The sequence of events that gave rise to the 7- to 10-fold rise in TSS in the late 1970s, particularly among young women aged between 18 and 24, is complex and amounts to a ‘perfect storm’ of factors. Rely tampons were designed to work better then ordinary cotton tampons by expanding more and preventing any menstrual blood escaping. The tampon therefore relied on a different design that included polyester foam cubes together with a gelling agent, carboxymethylcellulose, that would expand when immersed in blood. These were encased in a polyester pouch to form the ultra high-absorbency tampon.

Microbiologist Philip Tierno PhD postulated in his 2001 book The Secret Life of Germs that 4 factors conspired together: 1) the gelled carboxymethylcellulose acted as an ideal medium, like an agar culture plate, to allow Staphylococcus aureus,the same species associated with MRSA, to breed; 2) the pH of the vagina of a menstruating woman is raised from an acidic 4.2 or so during the non-menstruating phase of her cycle to around just over 7, ideal for S. aureusreproduction;  3) the tampon introduced oxygen and carbon dioxide to the normally anaerobic vagina, these gases aiding the bacteria, and; 4) the release of pyrogenic toxins from S. aureus cause infected women to develop a temperature that further enhances growth of the bacteria.

Following recognition that rates of TSS had soared to over 13 cases per 100,000, P&G withdrew its Rely tampons from the market at a cost of some US$75,000. P&G was sued by an 18-year-old girl who subsequently died from the effects of TSS. Tampons were then forced by the US, and subsequently other countries, to be registered as medical devices. Both polyester and carboxymethylcellulose were banned in tampons. As medical devices, it became compulsory to add a product information leaflet in tampon packs that explained risks and especially usage times, given that the longer a tampon is kept in place, the greater the risk of developing TSS or other vaginal infections. The consensus is that tampons should be changed every 4-6 hours with 8 hours being an absolute maximum.

Vaginal ecology is key

Only women who carry S. aureus are at risk of life-threatening TSS, but given that around 50% of women are carriers, the percentage who get it is tiny. We don’t understand all the factors involved. However, thanks to the Human Microbiome Project, a US National Institutes of Health (NIH) initiative “to characterize microbial communities found at multiple human body sites and to look for correlations between changes in the microbiome and human health”, we now know a lot more about vaginal microbial communities and their ecology. A healthy vagina is about having a stable ecology that is resilient to infections, and critical to this process is an appropriate environment around the vaginal mucosa. The acidic conditions and consequent rich cultures of lactic acid bacteria maintained by the production of lactic acid are hallmarks of healthy vaginal conditions that restrict the growth of pathogens and other opportunistic organisms. The presence of tampons during the period when the vaginal mucosa becomes more alkaline causes both physical and chemical interference in this normal ecology and mucosal function.

Whats a safe tampon?

Today’s tampons are far from homogenous. Some still use cotton and are unbleached and unscented. Others are chlorine-bleached, and contain cotton, or a mixture of cotton and synthetic fibres like rayon. Fragrances and dyes are commonly added as well. Since they are registered as medical devices, manufacturers are not forced to disclose to the public exactly what ingredients are used in their manufacture. They are evaluated by the registration authority, the TGA in the case of Australia, and the ones that make it to market are considered ‘generally safe’ assuming directions are followed (don’t forget that’s what regulators say about drugs…).
There are two problems. First, there is no such thing as absolute safety, and how would you feel if you were one of the 2 out of each 100,000 who get tampon-related TSS? Secondly, the long-term use and chronic or delayed toxicity effects are likely of greater concern to many, yet we simply don’t have data on these things. Our health is ultimately determined by the ways in which our genes are expressed, this in turn being the result of a complex interplay between our genes and environment, including our exposure to complex mixtures of chemicals.

Roundup in tampons

The latest tampon risk to hit the news has of course been glyphosate. The news came out of a somewhat obscure conference in Argentina and was first reported by RT.com in October 2015. The results were announced by Dr Damian Marino of the University of La Plata at the Third National Congress of Doctors for Fumigated Communities in Buenos Aires. Dr Marino claimed to find 85% of tampons, cotton and sanitary products tested contained detectable amounts of glyphosate, while 62% contained AMPA, the key metabolite of glyphosate. Concentrations found were in the order of 40 parts per billion (ppb) for AMPA and about half this amount for glyphosate. While the findings are of interest, they have yet to be validated elsewhere, and they are about one thousandth of the amounts that are typically found as residues in some fruits and vegetables according to the FAO.

Bleaching risks

Bleached tampons could pose a risk of low-level exposure to chlorination byproducts including dioxins and furans. While the levels of exposure would still be very low in bleached tampons, it is worth remembering just how readily the mucosa of a woman’s vagina, along with our eyes, or the mucosa within our mouths or inside our noses, absorb chemicals which are placed in contact with them. The mucosa is incredibly thin, highly porous and arguably poses less of a barrier than the gut. That’s why many naturopaths argue you shouldn’t put anything on your skin, least of all inside your vagina, that you wouldn’t put in your mouth.

For many women, the notion of giving up using tampons is unpractical. For others, swapping tampons for sanitary pads isn’t much of option either if both are made of the same material. I would argue otherwise: the tampon that is inserted internally will disrupt the ecology of the vaginal mucosa considerably more than the sanitary pad, and will also result in higher rate of absorption of any toxins.

Minimising risks

All up, using unbleached, organically certified cotton tampons, sanitary pads and other feminine care products appears to be the safest bet at present. You also won’t have to worry about the phthalates in the plastic applicator, and you should ideally go for an organic tampon that comes with compostable, rather than bioplastic, applicators.

Bearing in mind the risk of pathogens like S. aureus regardless of the tampon type, it’s also very important to change tampons every 4-6 hours, or as directed. For most, this means using organic pads, rather than tampons, overnight.


Robert Verkerk PhD is the founder, executive and scientific director of the non-profit, Alliance for Natural Health International (www.anhinternational.org). Through his work over the last 30 years in academia, commerce and the non-profit sector, he has been an outspoken advocate of working with, rather than against, nature. His work has spanned the fields of agriculture, healthcare, energy and the environment.



1.     Food and Agriculture Organization (FAO).  Pesticide Residues in Food. FAO Plant Production and Plant Protection Paper 183.  Glyphosate; pp. 122-143. [ftp://ftp.fao.org/docrep/fao/009/a0209e/A0209E00.pdf].

2.     Hickey RJ, Zhou X, Pierson JD, Ravel J, Forney LJ. Understanding vaginal microbiome complexity from an ecological perspective. Transl Res. 2012; 160(4): 267-282.

3.     Human Microbiome Project website: http://hmpdacc.org.

4.     IARC monograph on glyphosate. Volume 112, 2015 [http://monographs.iarc.fr/ENG/Monographs/vol112/mono112-09.pdf].

5.     RT.com article, 23 October 2015: Tampons, sterile cotton, sanitary pads contaminated with glyphosate – study [https://www.rt.com/usa/319524-tampons-cotton-glyphosate-monsanto/].

6.     Tierno, PM. The Secret Life of Germs: Observations and Lessons from a Microbe Hunter. Atria Books, New York. 304 pp.

7.     Vostral SL. Rely and Toxic Shock Syndrome: a technological health crisis. Yale J Biol Med. 2011 Dec;84(4):447-59.

8.     Woeller KA, Miller KW, Robertson-Smith AL, Bohman LC. Impact of Advertising on Tampon Wear-time Practices. Clin Med Insights Womens Health. 2015; 8: 29–38.

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