A recent study by scientists at Boston's Brigham and Women's Hospital has sparked concerns that phthalates, a common ingredient in beauty products, could be more harmful than first thought.
With this in mind, we decided to take a closer look at the chemical cocktail lurking within our bathroom cabinets.
The study, led by Dr. Tamara James-Todd, an expert in womens' health, found that women with the highest concentration of phthalates within their bodies were almost twice as likely to develop diabetes than those with the lowest concentrations.
Phthalates are considered "endocrine-disrupting," meaning that they can alter normal regulation of certain mechanisms within our bodies, and Dr James-Todd's study is just one of several which has linked the presence of phthalates to conditions such as diabetes.
The problem is that phthalates are almost impossible to avoid.
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Phthalates cling to the skin and nails, which is why they're found in up to 70 per cent of fragranced cosmetics, such as perfumes and body lotions.
A lack of research means that we don't yet know how harmful EDCs (endocrine-disrupting chemicals) are, but growing concerns recently prompted the European Environment Agency to issue a stark warning: "Scientific research gathered over the last few decades shows us that endocrine disruption is a real problem, with serious effects on wildlife, and possibly people", said EEA executive director Jacqueline McGlade.
"It would be prudent to take a precautionary approach to many of these chemicals until their effects are more fully understood."
Phthalates were one of five classes of chemicals Jacqueline McGlade singled out as a cause for concern, but EDCs aren't the only type of chemicals we're slathering onto our skin - here are some of the others.
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Yes, that's right. The stuff used by morticians to preserve dead bodies is also used in a wide range of beauty products, and is especially common in hair-straightening treatments.
"Formaldehyde is used primarily as a preservative and anti-microbial in thousands of cosmetics, including shampoos, creams (especially anti-aging creams) and makeup," points out Dr Peter Dingle, an associate professor within Health and Environment department at Perth's Murdoch University in Australia.
"It is known to cause eye, nose and throat irritation, coughing, shortness of breath, vomiting, skin rashes, nose bleeds, headaches and dizziness. It causes cancer in rodents and is a suspected human carcinogen."
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But, before you chuck out the entire contents of your bathroom cabinet and vow never to straighten your hair again, it's worth remembering just how small the quantities used in these products actually are.
Formaldehyde can only be used in cosmetics up to a concentration of 0.2 per cent and 0.1 per cent in oral hygiene products. However, in nail products, the maximum concentration increases to 5 per cent.
Some of the most potent chemicals can be found in products designed for use on our nails.
Acetone, which is used in products designed to remove super glue, is one example.
In addition to nail polish remover, it's used - albeit in small quantities - to "deep clean" before facial peels, due to its ability to remove debris and grease from the surface of the skin.
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"Acetone is a solvent," explains Dr Dingle. "It's a strong skin and eye irritant because of its solvent and de-fatting (removal of fatty acids) action on the skin. It can cause adverse effects on the respiratory and nervous system. It's extremely toxic but used minimally."
Propene glycol is commonly found in anti-freeze but you're equally likely to come across it in your moisturiser or make up, although in much smaller quantities.
Concentrations of 100 per cent are used in anti-freeze products, but the amounts used in beauty products are miniscule.
Tiny amounts of propylene glycol are used in cosmetic products to prevent the consistency changing in hot or cold temperatures and to help products penetrate the skin. As with many of the chemicals listed here, there are strict guidelines relating to the quantities which can be used.
Either way, Dr Dingle's prognosis makes for stark reading. "This is a skin conditioning agent and solvent used in a wide range of personal care products," he says. "It's absorbed through the skin and scalp. It can affect the liver and kidneys and is an eye and skin irritant, and has been proven to be a carcinogen in trials with animals."
Dr Dingle also points out that its increasing popularity could well lead to an increase in reactions.
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"A review of literature relating to propylene glycol suggests that there will be an increase in sensitivity or sensitisation because of the growing number of topical preparations containing the chemical," warns Dr Dingle.
Parabens have been around for years and are added to beauty products to give them a longer shelf life.
However, recent research by the Kyoto Prefectural University of Medicine has suggested that some types of paraben which were previously assumed to be safe, such as Methylparaben, could mutate when exposed to sunlight and lead to an increased risk of skin cancer.
Methylparabens can be found in 16,000 products, including body lotion, fake tan and blusher. In the past, producers of cosmetic products have argued that parabens are safe because they can't be absorbed into the body, but increasing numbers of scientists are now questioning this.
Additionally, parabens are one of the groups of EDCs singled out by the European Environmental Agency as a cause for concern.
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In summary, while many of the chemicals contained in everyday beauty products might well be harmful in larger doses, regulations relating to the amounts used mean that the quantities used are minimal.
But perhaps of more concern is that we simply don't know the ways in which many of these chemicals can affect us in the long term, or how they react when combined. Perhaps wrinkles aren't that bad, after all....
Looking to cut on the chemicals lurking within your beauty products? Here are some suggestions:
Mama Mio's Clean Slate Cleanser is paraben and sulphate-free - £22.50, www.mamamio.com
Lush's Bio-Fresh range of facemasks are all 100 per cent natural - £5.75, www.lush.co.uk
Vichy's Normaderm Hydrating Care is hypoallergenic, paraben-free and non-comedogenic - £12, Boots.
Moroccanoil's Extra Volume Shampoo is sulphate, phosphate and paraben-free - £17.65, www.lookfantastic.com
Bare Minerals Flawless Definition Mascara is paraben-free - £16.00, www.lookfantastic.com