I remember the last time I cleaned out my beauty drawer. Between you and me, it was a pretty filthy affair.

I found a Chanel mascara I’d been hulking around since 2008, a half-used Estée Lauder foundation I’d been hoarding for years since they discontinued it, once-swiped lipsticks, barely used blushers and an array of crazy coloured eyeshadows that I was adamant would come in handy one day.

But there’s a good reason why any decent make-up artist or beauty professional will urge you to purge your beauty bag frequently: because it’s the perfect breeding ground for a host of bacteria. Which could even be deadly.

New research recently found as many as six types of bacteria breeding happily on out-of-date cosmetics and beauty brushes – ncluding potentially lethal bacteria that can cause meningitis.

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Rakesh Aggarwal CEO of online beauty retailer escentual.com, who commissioned the research said: “Most women are totally unaware that their cosmetics are a potentially breeding ground for deadly bacteria.

“But if you think about it, you wouldn’t keep food for months after the use by date – so why should this be acceptable for cosmetics?”

“This research has even surprised us and has shown that there is a serious health risk here. Pregnant women or mums with small babies need to take extra care after our finding showed that the deadly meningitis bacteria Enterococcus Faecalis/Faecium was found on several items of out of date make-up.”

In total, six different types of bacteria were found on the five everyday high-street cosmetic products that were tested.

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Microbiologist Paul Matewele from the London Metropolitan University, where the tests were conducted, confirmed the test results, saying: “All the old make-up products of foundation, lip gloss and lipstick tested positive for Enterococcus faecalis under strict laboratory tests.

“Enterococcus faecalis is the potentially deadly strain of bacteria which causes meningitis and septicaemia, and is one of the biggest killers for newborn babies.”

What’s the oldest piece of make-up you’ve got in your beauty box? Tell us in the Comments box below.