Background The use of ultraviolet (UV)A lamps for curing gel nails is widespread in the cosmetic nail industry. A report that two women who had undergone this treatment subsequently developed squamous cell carcinoma (SCC) on the dorsum of hands has prompted some concern about the safety of this procedure.
Objectives To estimate the number of women who would need to be exposed to UVA nail lamps for one woman to develop SCC on the dorsum of hands, who would not have done so otherwise.
Methods A mathematical model that combines age and UV exposure was used to compare the risk of developing SCC due to typical sun exposure with the risk of inducing these cancers from exposure to UVA nail lamps.
Results For typical usage, the analysis indicates that tens or hundreds of thousands of women would need to use a UVA nail lamp regularly for one to go on to develop SCC on the dorsum of the hands as a direct consequence.
Conclusions The risk of inducing an SCC from exposure to UVA nail lamps is very low and one that is likely to be accepted by most women. Even then, the risk can be reduced to virtually zero by wearing fingerless gloves when the hands are being exposed.