Hormones work like keys in locks. Estradiol fits into estrogen receptors found throughout your body: in breast tissue, the uterus, the brain, bone and fat. Endocrine-disrupting chemicals, or EDCs, are substances that interfere with that signalling. Some, the xenoestrogens, are similar enough in shape to bind the estrogen receptor themselves. Others block it, or change how hormones are made, carried or broken down.¹ Phthalates, bisphenols, parabens and several chemical UV filters all belong to this group.

What makes them tricky is that hormones act at tiny concentrations. For EDCs, researchers have repeatedly found effects at low doses, and dose-response curves that are not a straight line: sometimes a low dose does something a higher dose does not.² “The dose makes the poison” is not the whole story here.

The tissue of your vagina and vulva is a mucous membrane: thin, moist, richly supplied with blood vessels, and without the thick protective outer layer of the rest of your skin. That is exactly why medicine uses it to deliver drugs. What is absorbed there reaches the bloodstream directly, bypassing the first pass through the liver that swallowed substances go through.³

Now picture a tampon: hours at a time, several times a day, a few days every month, for about forty years. Studies found phthalates, bisphenols and parabens in pads and tampons,⁴ volatile compounds linked to fragrance in scented products,⁵ and, in a 2024 analysis of 30 tampons, measurable levels of all 16 metals tested, with lead in every single one.⁶ How much of this actually leaches out and is absorbed has not been studied yet. That is the honest gap. But it is reason enough to choose a tampon whose contents you know.

Fresh menstrual blood smells of very little, at most faintly metallic, from its iron. The strong odour many of us associate with our period appears when blood sits for hours against plastic layers that trap heat and moisture: an ideal place for bacteria to break it down. The industry’s answer was fragrance. It hides the smell without solving its cause, and places extra chemicals right against the vulva.

“Fragrance” or “parfum” on a label can legally stand for dozens of undisclosed substances. When researchers analysed fragranced consumer products, each one released on average 17 volatile compounds; of the 133 different compounds found, 24 are classified as toxic or hazardous, and almost none appeared on the label.⁷ Synthetic scents often contain phthalates such as DEP, used to make a fragrance last. Breathable cotton and no perfume at all: that is the simpler fix.

No single toothpaste or pad is the problem. What matters is your total body burden: the sum of many small exposures. Toothpaste in the morning, sunscreen at noon, laundry detergent in your sheets, a dishwasher tablet and a scented candle at night. Biomonitoring shows that most of us carry several of these chemicals at once, and mixtures can act together even when each one stays below its own threshold.¹

Much of the clean-up happens in your liver. Through phase I and phase II detoxification, especially glucuronidation and sulfation, it makes these compounds water-soluble so you can excrete them. These are the very same pathways your body uses to clear its own estrogen. A heavier chemical load means more traffic on the same roads. Lowering what comes in is the part you can control.

Elvou starts from the ingredient list, not the packaging. Their tampons and pads are made of 100% GOTS-certified organic cotton, unscented, without rayon or viscose in the absorbent core, and the tampons are bleached without chlorine. Their toothpaste is fluoride-free with hydroxyapatite, the mineral your enamel is largely made of, which in a clinical trial in children protected against early caries as well as a fluoride toothpaste.⁸ Their sunscreen uses non-nano zinc oxide, a mineral filter that sits on the skin, instead of chemical filters such as oxybenzone, which in a clinical trial reached the blood well above the level the US FDA allows without further safety testing.⁹ And the laundry and dishwasher sheets clean without SLS or synthetic perfume.

Then there is what goes in: a whey from grass-fed Alpine cows with nothing added but real vanilla, no stevia, no sweeteners, and a grass-fed bovine collagen. Honestly some of the cleanest and best I have ever tried.