If you love to cruise the makeup counters, listen up: Those testers you like to sample in stores are likely to be teeming with bacteria, say researchers at Rowan University in New Jersey.

So what's the damage? The most likely scenario: "You could become infected with pinkeye or break out," says Elizabeth Brooks, DPM, one of the researchers. But testers and makeup counters were found to be contaminated with a variety of germs, from the type of staph bacteria found on doorknobs to E. coli, a fecal bacteria transmitted via contaminated hands.

The Dirt on Causes

Before you blame the stores, consider this: "At all the stores we visited, we routinely observed employees disinfecting cosmetic counters and the surface of makeup testers," says Brooks. That included using antimicrobial wipes, dipping lipsticks in alcohol, scraping powders, scooping out the top layer of creams, and sharpening pencils to a fresh point.

"The culprit turns out to be poor hygiene by customers," says Brooks. "As the day goes on, the samples become increasingly contaminated from dirty hands, sneezing, and coughing." How germy they ultimately get directly correlates with store traffic. "On weekends, when stores have the heaviest traffic, up to 100 percent of the testers showed contamination, while on Thursdays, levels dropped to 43 percent," she says.

Safer Makeup Trial

Your best bet is to try makeup at a counter helmed by a salesperson who can oversee hygienic usage, including single-use applicators. It's also smart to wash your hands with soap and water or use a hand sanitizer before and after visiting a makeup counter. If you can, avoid testing on lips and eyes, which are the most vulnerable to infection; use the back of your hand. Or use these safer ways to try new products.

• When trying on lipstick... Wipe off the top layer with a tissue. Dab the color onto your lips with a cotton swab.
• When trying on eye shadow... Use a cotton swab to brush the color onto your brow bone. Steer clear of your eyelids.
• When trying on solid foundation... Remove the top layer with a tissue, then use a disposable makeup sponge to apply the product to your skin.
• When trying on lotion... Avoid the jarred variety. Stick with lotions that are in a tube or a container with a pump.
• When trying on blush... Spritz an alcohol-based spray onto the communal makeup brush, let it dry for a minute or two, then swipe the blush onto your cheeks.

Great Results Without Sampling

If you want to skip the trials completely, you can:

• Buy from a return-friendly store. Don't use testers at all—just buy your makeup from a store where you can return it. Inquire about the specifics of the return policy first.
• Go for a free virtual makeover. Taaz.com lets you test-drive makeup shades on a photo of your face (or a model you choose). Just click "upload" to add a snapshot of yourself, click on any facial feature, and select from a palette of products from more than 30 drugstore and department store brands. Another advantage: No one will see if that green eye shadow really doesn't work for you.