NewsChannel5 reports that over time, makeup becomes contaminated with bacteria, which can lead to eye infections and skin problems.

People can help prevent contamination of products by keeping brushes clean and washing hands before applying makeup.

But how long is too long to keep makeup?

Experts recommend tossing mascara every three to six months. For liquid foundation, two years is the rule. For other makeup, products are tested for a shelf life of one to three years. After three years, experts advise throwing products away.