Nail salon dryers, which use ultraviolet light to speed the drying and hardening of nail polishes and gels, emit varying levels of radiation that can lead to risky skin damage in as few as eight visits to the manicurist, a new study shows.
The nail dryers emit primarily UVA light – the same kind of ultraviolet light used in tanning beds – and are used to dry nail polish or to harden a gel manicure. Gel manicures are popular because they create long-lasting, shiny nails created by a chemical gel that is painted on the nail in layers and cured under UV light after every coating.
Case reports of two women who developed squamous cell skin cancers on their hands have suggested an association between cancer and the UV nail light devices, but most doctors agree the risk is low.
In the new study, researchers from Georgia Regents University in Augusta conducted a random sampling of 17 UV nail lamps found in salons to determine how much ultraviolet radiation is being emitted when clients dry their nails under the lights.
The study, published as a research letter last week in the journal JAMA Dermatology, found wide variation in the dose of UVA light emitted during eight minutes of nail drying or hardening. The dose, measured in joules per centimeter squared, ranged from less than 1 to 8.
“There is a vast range in the amount of light coming out of these devices,” said Dr. Lyndsay R. Shipp, the study’s lead author and a postgraduate resident at Regents University’s Medical College of Georgia. The amount of UV exposure ranged from “barely” to “significant,” she said.
DNA damage that can lead to skin cancer is known to occur at about 60 joules per centimeter squared, and none of the nail lamps came close to that number. However, the researchers estimated that for most of the lamps tested, eight to 14 visits over 24 to 42 months would reach the threshold for DNA damage to the skin.
The study authors noted that “the risk from multiple manicure visits remains untested,” but the study suggests that “even with numerous exposures, the risk for carcinogenesis remains small.”
Shipp said she sometimes used the nail lamps and would continue to do so.
“I do use them every couple of months,’’ she said. “You can get that amount of exposure when driving down the road in your car.”
