Whether you’re an Egyptian woman from 15th century B.C. or a present day menstruating individual, chances are that you’ve used a tampon (Weissfeld, 2010). The tampon acts as an absorbent ‘plug’ which is placed in the vagina for several hours during menstruation to absorb blood as it exits the cervix from the uterus. It is estimated that within a menstruators reproductive years “More than 7,400 tampons (4 tampons/day x 4 days/cycle x 12 cycles/year x 39 years of cycles)” may be used by each woman (Shin, Lee, & Chung, 2009). Though various materials—including wool, paper, vegetable fibers, and grass—have been used throughout history, in modern times the most commonly used material is a mixture of cotton and rayon/viscose (Weissfeld, 2010).
For many, the modern tampon has been quintessential in daily life. Its sleek shape provides an alternative to the sanitary napkin (pad) and allows for increased mobility, decreased noticeability, and reduced bulk. In the United States alone, 52-86% of menstruators use the tampon (Shin, Lee, & Chung, 2009), with a global market size valued at 4.9 billion USD in 2022. It is estimated to reach 8.7 billion USD by 2031, growing at a CAGR (compound annual growth rate) of 6.2% during the forecast period (2023–2031) (Straits Research, 2023). One of the main qualities of the tampon is its internal placement, preventing blood from exiting the body. This contrasts with other forms of sanitary care, such as pads, which are external and capture blood as it is exiting the body. Despite the benefits associated with tampon usage, its internal application poses some additional concerns, primarily pertaining to the contents of the tampon.
The Research
A recent study published in 2024, aimed to explore and quantify the contents of heavy metals and metalloids contained within tampons. The study tested for the presence of 16 different metal(loids)–which include arsenic, cobalt, chromium, nickel, copper, cadmium, and lead–in 30 tampons from 14 different brands. The tampons varied by three factors: sourced from the US or EU/UK, organic or non-organic, and store- or name- brand. Of the metals found, lead (Pb=120 ng/g) had the highest mean concentration of metals, followed by nickel (Ni=80.1 ng/g), copper (Cu=78.9 ng/g), cobalt (Co=19.8ng/g), cadmium (Cd=6.74ng/g), arsenic (2.56ng/g), and chromium (Cr) with the lowest mean concentration. Among the organic/non-organic category, lead concentrations were higher in non-organic tampons, whereas arsenic was higher in organic tampons. Their investigations revealed that lead, cadmium, chromium, and arsenic could be found in all of the tampon samples and that none of the examined groups had consistently low quantities (Shearston, et al, 2024).
Although the study mentioned above claims to (potentially) be the first examination of heavy metals in menstrual products, a Korean study conducted in 2009 produced similar results. Their study examined the content of heavy metals–cobalt, chromium, nickel, copper, cadmium, and lead–in Korean, Japanese, and American tampons. It was found that copper had the highest overall concentration, with a range of 288-3509 ng/g and an average of 1354 ng/g. Similar to the 2024 study, lead was also found in elevated concentrations with a range of 83-872 ng/g and an average of 383 ng/g. They concluded that the metals, nickel, copper, and lead were present across all of the samples tested and that cobalt and cadmium were only present in a few samples with relatively low concentrations (Shin, Lee, & Chung, 2009).
Why is This a Relevant Health Concern
If you’ve moderate scientific knowledge, you know that heavy metals in significant quantities aren’t healthy for humans. When in acute or chronic contact with skin, heavy metals can result in a variety of skin diseases, including skin cancer and contact dermatitis (Mitra, et al, 2022). Even more alarming, when heavy metals enter the circulatory system and are not metabolized by the body, they accumulate in soft tissue and can become toxic to other parts of the body, such as the liver, the bones, the cardiovascular system, and the reproductive system (Shin, Lee, & Chung, 2009). In females, infertility is attributed mainly to heavy metal poisoning in the reproductive system, which results in hormonal imbalances and subsequent infertility complications. According to the World Health Organization (WHO), 10% of women are at risk of infertility due to heavy metal (including lead and cadmium) exposure (Mitra, et al, 2022).
Contrary to the skin, which acts as a barrier for the body's internal organs, the vaginal canal is highly permeable. Its anatomy consists of folds known as rugae, made of vascularized mucous membranes, allowing for efficient chemical absorption. Moreover, when the vagina absorbs chemicals, they are not detoxified by the liver and instead directly enter the circulatory system. If heavy metals were to come into contact with the vaginal tissue, their absorption, and effects would be significantly different from skin contact (Shearston, et al, 2024).
To explore permissible levels of heavy metals in sanitary products, the Korean study also compared their determined concentrations to the 100 ÖKO TEX Standard—a certification system used to set a criteria for permissible levels of harmful substances in textiles and related materials, based on skin to textile contact. In accordance with the standard, they deemed that the levels of heavy metals found in tampons were allowable. However, this conclusion raises questions about the validity of using the 100 ÖKO TEX Standard to set limits for harmful substances in internally inserted sanitary products like tampons, given the vagina's increased permeability (Shin, Lee, & Chung, 2009).
Further Considerations and Conclusion
The presence of heavy metals in tampons may indicate a larger contamination issue within the environment. It has been noted that a possible route through which heavy metals arose in tampons is through wastewater used for irrigation purposes, fertilizers or pesticides, and atmospheric deposition (caused by anthropogenic atmospheric contamination). These sources of contamination may result in the consequent uptake of metals by plants–such as cotton–used in tampon production (Shearston, et al, 2024).
Around the world, women rely on sanitary products to provide them with a safe and comfortable way to manage their menstrual cycle. With the determination of heavy metal content in these products, their well-being, as well as their safety, may be at risk. To better understand the necessary actions to be taken and the effects of harmful metal substances in tampons, further research must be conducted. This primarily requires increasing awareness, advocacy, and research on women’s health. Although the issue at large may be more complex, the implementation of stricter regulations and relevant criteria provides hope for a future free of heavy metal contamination in sanitary products.
Written by Gaia Soldano and edited by Aldrin V. Gomes, PhD
References
Weissfeld, S.A. (2010). The History of Tampons: from Ancient Times to an FDA-Regulated Medical Device. ScienceDirect, 32(10), 73–76. https://www.sciencedirect.com/science/article/pii/S019643991000019X
Shearston, A.J., Upson, K., Gordon, M., Do, V., Balac, O., Nguyen, K., Yan, B., Kioumourtzoglou, M.-A., Schilling, K. (2024). Tampons as a source of exposure to metal(loid)s, ScienceDirect, 190, 108849. https://www.sciencedirect.com/science/article/pii/S0160412024004355
Shin, J.-H., Lee, K.-K., & Chung, M.-H. (2009). Determination of heavy metals in sanitary products of women. Journal of the Korean Society of Clothing and Textiles, 33(6), 853–859. https://doi.org/10.5850/jksct.2009.33.6.853
Mitra, S., Chakraborty, A. J., Tareq, A. M., Emran, T. B., Nainu, F., Khusro, A., Idris, A. M., Khandaker, M. U., Osman, H., Alhumaydhi, F. A., & Simal-Gandara, J. (2022). Impact of heavy metals on the Environment and Human Health: Novel therapeutic insights to counter the toxicity. Journal of King Saud University - Science, 34(3), 101865. https://doi.org/10.1016/j.jksus.2022.101865
Srikrishna, S., & Cardozo, L. (2012). The vagina as a route for drug delivery: A Review. International Urogynecology Journal, 24(4), 537–543. https://doi.org/10.1007/s00192-012-2009-3
Comments