Should You Still Use Nail Polish That's Separated?

Whether you're hesitant to toss your go-shade of summer '15 or debating if last year's glittery gold top coat is still usable for this year's holiday parties, knowing when old polish is just too old can sometimes be tricky. For instance, is it still okay to use if the color has separated? What about if it's just sticky? And if it has gone bad, is there an eco-friendly way to dispose of it? We turn to the polish experts at Essie to find out, plus the best storage tips to keep your tiny bottles in the best shape.

CAN YOU STILL USE NAIL POLISH THAT'S SEPARATED?

In most cases, yes. Stephanie Bruno of Essie's product-development team explains that polish separates because the colorants-pigmented particles suspended in the formula-vary in weight. Heavier ones tend to settle at the bottom over time, but rolling the bottle between your hands will remix them sufficiently for use.

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WHAT ABOUT IF POLISH HAS GOTTEN A BIT STICKY?

If you're spotting stringy globs of polish while pulling your brush out of the bottle, fear not - your polish isn't a total goner. This may just mean it's inching up to the end of its life span, which Bruno says is a standard two years from when the bottle is first opened. To revive, simply add a few drops of pure, undiluted acetone to the bottle which can help the lacquer hold out for a few more applications. However, Rita Remark, Essie's global lead educator, warns not to add too much: "Overdoing it can make your polish runny or cause the pigments to separate." In this case, less is more.

WHERE'S THE BEST PLACE TO STORE POLISH IT TO KEEP IT LONG-LASTING?

To keep your favorite shades in tip top shape, Remark recommends storing bottles in a dark, dry place like a cupboard or a drawer. "Too much light or heat can alter the composition of the lacquer and lighten the pigments." Another maintenance rule-of-thumb: Keep the mouth of the bottle clean by wiping it with a bit of nail polish remover after each use. Otherwise, polish can quickly build up and prevent the lid from sealing fully. "This then allows air in, which can thicken the polish."

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HOW DO I KNOW WHEN IT'S TIME TO TOSS?

If you aren't able to successfully re-blend an old polish or find it's too crumbly to use-or it's past the standard two-year shelf life-just consider this the perfect excuse to splurge on that adorable shade you've been eyeing.

HOW SHOULD I DISPOSE OF OLD NAIL POLISH?

It may not seem like much to toss a half-empty bottle of polish in the trash but Bruno reminds us: "We recommend to never throw nail polish in the garbage can or pour it down the sink." According to the U.S. Environmental Protection Agency, because of their chemical compositions, nail polishes are considered to be household hazardous waste and should be disposed of responsibly. Therefore, Bruno suggests taking any old polish and polish remover to a local waste facility or collection site near you (find yours here).