MAKEUP Q & amp;A

Q. How do I know if my makeup is still good?
A. Cosmetics aren't required by law to have expiration dates, so you can't just look at the label to know when a product is iffy at best. Experts vary in their keep-it, toss-it guidelines, but they all agree that mascara lasts the shortest amount of time and is the likeliest to cause problems, including eye infections such as conjunctivitis ("pink eye").
Hardly anything can be done to lessen the contamination of mascara once you use the wand on your lashes and shove it back into its dark, moist, bacteria-breeding container.
"Mascara is definitely the main offender," says Melissa Cable, who works as an ophthalmologist in the Kansas City area with Discover Vision Centers.
She recommends tossing mascara after as little as three months. Others say toss it after two.
(How do you know whether you might have an eye infection, from eye makeup or another source? If you have any change in vision, especially blurred vision, pain or a discharge in the eye, call your eye doctor immediately, Cable says.)
Other general guidelines: Dump eyeliner, eye creams and face creams after six months or so. Toss liquid cosmetics, such as foundations, every year (some advise after four to six months). Lipsticks and pencils? One to two years. Powdered products, such as eye shadow, blush and face powder can last longer -- up to three or more years. But those guidelines depend on how sloppily you use the products.
If you don't know when you bought a product, you can gauge its safety with a critical sniff 'n' look.
"If it smells, that's a huge tip-off that you should not be using that product," says Babette Crowder, owner of Babette beauty boutique in Lawrence, Kan.
Likewise, if the product has changed color or consistency, is cakey or has separated, then it's time to toss it.
Note however that some products, such as makeup base, darken a little naturally as you use them because of oxidation, says Doug Sheward, co-manager of Terry Binn Skincare Inc. in Mission, Kan.
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