USA, New Research: UV Protection On Sunglasses Not Cut by Cleaning

Researchers based at Pacific University in Forest Grove, Oregon, found that subjecting six pairs of non-prescription sunglasses to nine months of cleaning --either using soap and face tissues or a lens cleaner and soft cloths-- did not diminish the ability of the sunglasses to shield wearers from harmful UV rays.

During the study, study author Dr. Citek and his colleagues tested six non-prescription sunglasses, some under $15, some between $15 and $30, and others that were $30 and up. The lenses were cleaned for a simulated period of nine months, one lens with a water-based lens cleaner and a soft cloth, and the other with Ivory soap and warm water that was dried with face tissue. Citek and his colleagues presented their findings during the recent meeting of the American Academy of Optometry in San Diego.

Dr. Jeffrey Weaver of the American Optometric Association, who reviewed these findings for Reuters Health, said that while the soap used in this particular study may not diminish UV protection, other brands may contain alcohol or other harsh ingredients that could strip lenses of their protective qualities. So not all soap is safe, he noted. Face tissue is wood-based, he added, and could become abrasive to sensitive lenses. "So using a water-based product and a soft cloth is your best approach" when cleaning your lenses, Weaver said.

While these results suggest that UV protection can last through cleaning, Citek said, consumers should still be careful to buy sunglasses that start out with enough UV protection. "To ensure that non-prescription sun eyewear has adequate UV protection, we recommend that consumers purchase recognizable brand name eyewear from reputable stores and optical shops, and not from roadside stands," Citek said. The limits of UV absorption are set by the American National Standards Institute, a nonprofit organization that coordinates a system of voluntary standards in the US.