The worrying substances that might be in your tampons.

Image via iStock.

It’s predicted a woman will use over 11,000 tampons in her lifetime. That’s a lot of trips down the sanitary products aisle.

Yet despite the cute and colourful packaging and how common an item they are, apparently no one really knows exactly what is in your tampons. Shit.

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Well that’s not strictly true – of course the manufacturers know exactly what they’re putting in them, it’s just us (you know, the actual users of the product) that are kept in the dark.

In fact, there is no conclusive research that can say with absolute confidence that most feminine hygiene products are 100 per cent safe. It’s only recently that any study has actually looked into it, with the majority of research being done by independent bodies.

A recent report by the non-profit Women’s Voices for the Earth found out that some feminine hygiene products may use ingredients that are known or suspected endocrine-disrupting chemicals (EDCs), carcinogens (agents that are directly involved in causing cancer) or allergens.

And using other products like douches, wipes and deodorizers only increases the risk of potential chemical exposure.

According to Naturally Savvy, the main ingredients in some commercial tampons are typically a blend of synthetic rayon and cotton, but it has been noted that some companies have mixed a variety of fibres with the cotton over the years to try to improve absorbency and maintain the tampon's shape inside the body.

Some of these can include polyester, collagen, acetyl cellulose, polyurethane (commonly used in foam) and - shockingly - even asbestos in the 1950s. There's also concern about the effects of the pesticides and chemicals that are used in actually producing the cotton.

Kind of worrying considering we're putting them in our vaginas every month, right?

The "lack of transparency" problem lies in the fact that both tampons and pads are considered "medical devices". In the US this means companies test them before submitting them to the Food and Drug Administration (FDA) before they're allowed to go on the market.

Even after they've been approved, companies are not legally required to list their ingredients.

A similar process is in place with the Australian equivalent, the Theraputic Goods Administration. While you can access public summaries of the products on the Australian Register of Theraputic Goods, guess what information isn't readily accessible? The ingredients.

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It's no surprise then that critics, particularly in the US, are concerned that the process prevents the public from accessing health risk information that affects their ability to make informed decisions about whether they should be using these products.

In fact, a New York congresswoman called Carolyn Maloney is attempting to reintroduce (for the tenth time!) a bill "to establish a program of research regarding the risks posed by the presence of dioxin, synthetic fibres, chemical fragrances, and other components of feminine hygiene products."

"Despite the large investment women make on feminine hygiene products and their high usage, there has been limited research on the potential health risks these products may pose to women," she told RH Reality Check. (Post continues after gallery.)

While there's no doubt that greater transparency is needed, Sapphire Family Medical Practise General Practitioner Dr Daria Fielder says there's no need to chuck out all your tampons in panic just yet.

"Manufacturers have to pass all the safety standards, so I don't think it's anything anyone should be overly worrying about," she says.

If you are concerned, try using TOM's certified organic tampons and pads which are chemical free.

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A more common fear with tampons is Toxic Shock Syndrome (TSS), where toxins are released into the bloodstream by bacteria.

Dr Fielder is quick to point out while it's certainly something we should all be aware of, it's generally incredibly rare.

"Less than one per cent of tampon users are at risk," she says.

"It's also important to know that tampons are just one way of getting TSS - men and children can get it too. It's caused by any foreign object being in the body for too long," she says.

In somewhat reassuring news, if you do get it, you'll know about it.

"They aren't subtle symptoms - you'll feel very sick, nauseous, faint, have abdominal pain, a temperature and might see a flaky rash all over your body that looks like peeling skin," Dr Fielder says.

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If you really want to reduce your risk of contracting TSS through tampon use, Dr Fielder has a few recommendations.

"Stay away from super absorbent tampons as most people think this means they can leave them in for longer - it doesn't."

"Also try to change your tampon every four hours, and I'd recommend using pads at nighttime," she says.

"And of course, if you're feeling unwell whilst wearing them, see a doctor."

Have you ever had trouble with your tampons?