Hidden bacteria lurking in your make-up?

A word of warning: a woman's make-up could cause the exact problems it's designed to hide.

"It could cause infections of their hair follicles and that can look a little bit like acne sometimes," says dermatologist Dr. Ramsey Markus, M.D.

Dr. Markus agreed to help test 19 makeup samples collected from several volunteers, including hair stylist Gina Ortiz and salon owner Cara Crafton.

"It's sitting at the bottom of my purse, then I take it home and use it at home, and it's in the bathroom, then back in my purse. It's all over the place," says Ortiz.

"I'm hoping it doesn't come back with lots of interesting friends," says Crafton.

Dr. Markus swabbed the samples, everything from cream to liquid to powder, then sent them to a lab for analysis. The results came two weeks later with staph and strep.

Six of the samples tested positive for the bacteria the doctor called unacceptable. A liquid make-up contained streptococcus, the same bacteria that causes strep throat.

"It can cause a variety of skin infections. Impetigo, for example, can be caused by strep and that's a gold, honey colored crusty type of a skin infection," says Dr. Markus.

The most alarming sample, according to the doctor was a liquid-powder foundation. It contained MRSA -- the drug-resistant form of staph that can lead to hospitalization.

"Especially if you had a poor immune system, absolutely," says Dr. Markus.

So what can you do to keep your make-up germ free? Dr. Markus says a good rule is to throw it out after about three months and remember to toss those reusable make-up sponges.

On a positive note, the samples belonging to the two hairdressers were germ free.

The doctor also recommends washing applicator sponges regularly and even putting them in the microwave for about a minute to kill germs.

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