That old makeup you keep in your kit is a host for killer bacteria, a new study has revealed. Scientists from the London Metropolitan University Biomedical Science did a laboratory test on five out-of-date cosmetic products and learned that they contained alarming levels of a potentially lethal bacteria, according to a press release.

From among the lip gloss, foundation and blushes tested, the microbiologists found traces of enterococcus faecalis.

"Enterococcus faecalis, is the potentially deadly strain of bacteria which causes meningitis and Septicaemia and is one of the biggest killers for newborn babies," the experts said, according to Huffington Post U.K.

The old makeup also tested positive for the presence of these other bacteria:

- Eubacterium, which is linked to bacterial vaginosis.

- Aeromonas, a bacteria found in gastroenteritis and wound infections.

- Staphlyoccocus epidermidis, a bug that is resistant to antibiotics.

- Propionibacterium, which can cause acne and other skin conditions.

- Enterobacter, which can lead to urinary and respiratory tract infections.

The products came from beauty bloggers and the test was commissioned by beauty retailer Escentual. "I'm absolutely shocked that my blusher contains bacteria that could cause meningitis and septicaemia. I was aware that I had kept it well past its use by date but didn't think for a minute that a blusher to [sic] contain killer diseases growing in it," said Laura Byrne, a beauty blogger from London, according to Daily Star.

"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," said Escentual CEO Rakesh Aggarwal.

Previous recommendations by makeup and beauty experts have already indicated the need for throwing away old makeup. For additional information on makeup's lifespan, check out this infographic:

 

Expired Makeup Inforgraphic
(Photo : Pinterest/Buzzfeed)
A proper breakdown of when makeup must be thrown away.