First we had to learn to apply eyeliner. Then we had to decide on an eyeliner look. Now a new study tells us to trash it all, because eyeliner may harm our vision. If you apply liner on the inner eyelid, you risk contamination that could eventually lead to vision trouble, according to Science Daily (via The Frisky).

The study proved that particles from pencil eyeliner really do end up in your eye. The team of researchers at University of Waterloo used video to observe different styles of makeup. They discovered that makeup moved into the tear film, AKA the thin coating that protects the eye, most quickly when eyeliner was applied to the inner lid. They found that eyeliner can alter the tear film, which may cause discomfort.

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“People who wear contact lenses are most likely to notice some problems,” said Dr. Alison Ng, the study’s director. “If they have eyeliner stuck to their lenses, increasing deposits might cause vision disruption as the lens becomes cloudier.”

Dr. Ng doesn’t expect people to give up eyeliner altogether. “If you thoroughly sharpen your pencil eyeliner before each application and get rid of the stuff that’s stuck to the end, you’ll have a fresh tip which can help prevent infection,” she suggested. If you use twist-up eyeliner, you should cut a bit off the end each time. And, of course, never go to bed with eye makeup on!

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