Researchers from Rapid Precision Testing Laboratories have found that UV nail lamps are safe and to not cause cancer. After the lamps became popular in the last few years for curing non-chip gel nail polish, many began to question their safety.
The research, headed by John C. Dowdy, PhD, and Robert Sayre, PhD, was published in Photochemistry and Photobiology, in the article "Photobiological safety evaluation of UV nail lamps."
The lab evaluated six UV nail lamps representative of major U.S. manufacturers to evaluate radiant hazards as defined in ANSI/IESNA RP-27 Recommended Practice for Photobiological Safety. Lamps were evaluated at three positions, 1 cm above the inner surface approximating exposure to the hand and the 20 cm RP-27 non-general light source distance, oriented normal and 45° to the opening. Hazard to skin at intended use distance classified these devices into Risk Group 1 or 2 (Low to Moderate) with S(λ) weighted Actinic UV ranging 1.2-1.7 μW cm(-2) and 29.8-276.25 min permissible daily exposure.
At 20 cm on center and 45° UV, risk to skin and eyes were all within Exempt classification. Actinic UV ranged 0.001-0.078 μW cm(-2) and unweighted near UV (320-400 nm) ranged 0.001-0.483 mW cm(-2). Likewise, the retinal photochemical blue light hazard and retinal thermal and cornea/lens IR were also Exempt. One device had aphakic eye hazard slightly rising into Risk Group 1 (Low). There were no other photobiological risks to normal individuals. Total exposure following programmed times and steps accumulate to only a small fraction of RP-27 permissible daily occupational exposure. These risks are further mitigated in realistic nonoccupational use scenarios, as it is unlikely to be a daily occurrence.
Therefore, the study found UV nail lamps to be safe for both in-salon and at-home use. Also, it found that they pose a low threat to developing non-melanoma skin cancer, determining the risk to be 11-46 times lower than noonday sunlight. They also found that it was nearly impossible to exceed safe levels of exposure with the nail lamps.