Just in time for Halloween trick or treating, the Centers for Disease Control and Prevention is out with new numbers to guide some final costume choices. And it has nothing to do with the outfit but the accessories.

The CDC says 46 million people wear contact lenses daily, and depending on the kind, can cause eye infections. An October study published in Morbidity and Mortality Weekly says as many as 80 percent of people who wear contacts suffer infections.

Eric Kawulok is an optometrist with the Mayo Clinic in Phoenix.

“And especially if they are not fit appropriately or if someone were to go and buy them over the counter, they could potentially damage the surface of the eye and lead to infections, ultimately permanent vision loss," Kawulok said.

A study published in Science and Clinical Practice in 2003 about fashion contact lenses says problems can be as serious as blindness. Either through the materials of creating the colors or the manufacturing process of creating the lenses, cosmetic and specialty eyewear do not generally go through medical approvals.