This is the most disgusting item inside your makeup bag

Up to 90% of the make-up analysed had detectable levels of bacteria. [Photo: Getty]

You might want to throw out all of your used makeup products after finding out what’s living in some, with as many as nine in 10 products potentially swarming with dangerous bacteria, research suggests.

Scientists from Aston University in Birmingham looked for microbial contamination in more than 460 donated lipsticks, lip glosses, eyeliners, mascaras and “beauty blenders”, sponges used to apply foundation.

They found between 79 per cent and 90 per cent of the makeup had detectable levels of bacteria, including E.coli.

Although usually harmless, certain strains can trigger diarrhoea, urinary tract infections and even pneumonia, according to the Centers for Disease Control and Prevention.

Staphylococcus aureus was also present. This has been linked to everything from wound infections to blood poisoning, with certain strains - like MRSA - not responding to common antibiotics, the UK government reports.

Beauty blenders were found to be the worst offenders, with more than a quarter (26 per cent) having “faecal matter present on them”.

Beauty Blenders are the dirtiest thing in your makeup bag. Photo: Getty

Nearly all (93 per cent) of those donated had never being cleaned, the results - published in the Journal of Applied Microbiology - show.

Even when the sponges are scrubbed, failing to properly dry them before use could create the perfect breeding ground for damp-loving bacteria, the scientists warn.

More than half (64 per cent) of the women involved also admitted to dropping their beauty blenders on the floor, only to pick them up and carry on.

“Consumers' poor hygiene practices when it comes to using makeup, especially beauty blenders, is very worrying when you consider that we found bacteria such as E.coli - which is linked with faecal contamination - breeding on the products we tested,” co-lead author Dr Amreen Bashir said.

With more than 6.5 million beauty blenders sold worldwide, the scientists worry the trend for contouring may be putting women at risk.

While many strains of the bacteria found can be harmless, makeup users are still putting themselves at risk if they apply contaminated products near their eyes, mouth, or any cuts or grazes.

Women admitted to using dirty beauty blender's near their eyes. Photo: Getty

Those with weakened immune systems, such as cancer patients on chemotherapy, may be particularly vulnerable.

The scientists are calling for more prominent expiry dates on makeup packaging, as well as cleaning instructions.

How to keep your makeup bacteria-free

To avoid bacterial contamination of your cosmetics, Dr Bashir recommends washing your hands and face before applying any products.

She also advises throwing away cosmetics once they pass their expiry date.

Keeping makeup brushes and sponges clean can also reduce contamination. For beauty blenders, Dr Bashir recommends rubbing them against a bar of soap under warm running water.

While it may sound obvious, she also stresses you should “never ever” share makeup.

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