Study finds 16 metals in widely available brands of tampons

In a recently published study in the journal Environment International, a team of US researchers looked at the presence of metals in tampons, which are widely used by women during menstruation.

The study tested 30 tampons from 18 product lines and 14 brands for 16 metals or metalloids and compared metal concentrations according to tampon characteristics.

Nearly 50% of the world's population is biologically female and experiences menstruation. Menstruation begins on average at age 12 and continues until menopause, which occurs around age 50, and menstruating women bleed an average of four days each menstrual cycle, which occurs every 29 days.

A significant proportion of menstruating women use tampons to manage their bleeding. Tampons are inserts made of rayon, cotton or rayon that can be inserted into the vagina where they absorb menstrual blood.

Previous studies have identified a variety of chemicals in tampons, including polycyclic aromatic hydrocarbons, parabens, volatile organic compounds, dioxins, etc.

However, few studies have examined the potential exposure to metals through tampons.

In the current study, the researchers sought to measure the concentrations of 16 metals or metalloids in 14 brands of tampons. The study looked at the presence of the following metals in tampons: arsenic, barium, calcium, cadmium, cobalt, chromium, copper, iron, mercury, manganese, nickel, lead, selenium, strontium, vanadium, and zinc.

A total of 30 samples of five different absorbency levels were tested, representing 18 product lines (different tampons from the same brand) and 14 brands.

The samples included popular brands from online retailers and "store brands" from major retail chains in the United States. Tampons were also purchased from online retailers in Greece and the United Kingdom.

Tampons typically consist of an absorbent core, which in some tampons is surrounded by a non-woven outer covering, and a string to facilitate removal.

If an outer coating was present, samples were taken from both the absorbent core and the outer coating. Samples were acid digested and all were processed in duplicate.

All metal concentrations were measured using inductively coupled plasma mass spectrometry, although a slightly different method was used to measure mercury concentrations compared to the other metals. The method detection limit and method quantification limit were calculated.

The distributions of metal concentrations in tampons were characterized and the heterogeneity of metal concentrations within tampons was assessed.

The researchers also compared the variability in metal concentrations within tampons with the variability between tampons.

In addition, median values of metal concentrations in tampons were used to compare variability between inorganic and organic tampons, tampons with a cardboard or plastic applicator and tampons without an applicator, store brands and name brands, and tampons purchased in the United States, United Kingdom, and Greece.

The study found the presence of all 16 metals in the various types and brands of tampons they tested.

Significant concentrations of several toxic metals such as cadmium, lead and arsenic were detected, but the presence of mercury or chromium was negligible. Calcium and zinc were found in higher concentrations compared to other metals.

Variability in metal concentrations within a tampon was low, but variability was high between different tampon types and brands.

Metal concentrations also varied significantly across tampon characteristics, such as inorganic versus organic tampons, name brands versus store brands, and tampons purchased in the UK or Europe versus those purchased in the US. However, none of these categories had consistently low concentrations of all metals.

Of particular concern was the presence of lead in all tampons tested. Lead leaching into the bloodstream can lead to deposits in bones, which replace calcium and can persist in the body for long periods of time.

Even low levels of lead are known to have toxic effects on the nervous system and behavior, as well as on kidney, reproductive, immunological, cardiovascular, and developmental health.

The study also discussed the toxic effects of other metals found in the tampon samples. Contamination of tampons with these metals may occur at the manufacturing stage, through atmospheric precipitation or wastewater from the production of raw materials.

This can also occur during the manufacturing process or through products added to tampons for antimicrobial effect, lubrication, or odor control.

Overall, the study found that a wide range of tampons sold online or in large retail chains in the US, UK and Europe contained trace or significant amounts of 16 metals, most of which have toxic effects on the body.

Given that these metals can leach out during use and be absorbed into the body through the vaginal epithelium, directly entering the bloodstream, further research is needed to confirm these findings, after which strict manufacturing standards for tampons are required.