Pre-mutagenic and mutagenic changes imprinted on the genomes of mammalian cells after irradiation with a nail polish dryer

Ultraviolet A light (UVA) is commonly emitted by nail polish dryers with recent reports suggesting that long-term use of UV-nail polish dryers may increase the risk for developing skin cancer. However, no experimental evaluation has been conducted to reveal the effect of radiation emitted by UV-nail polish dryers on mammalian cells. Here, we examine the pre-mutagenic and mutagenic changes imprinted on the genomes of human and murine primary cell models due to irradiation by a UV-nail dryer. Our findings demonstrate that radiation from UV-nail devices is cytotoxic and genotoxic. Importantly, high levels of reactive oxygen species were observed in all irradiated samples. Analysis of somatic mutations revealed a dose-dependent increase of C:G>A:T substitutions in irradiated samples with a pattern consistent to the one of COSMIC signature 18, a mutational signature attributed to reactive oxygen species. Examination of previously generated skin cancer genomics data revealed that signature 18 is ubiquitously present in melanoma and that it accounts for ~12% of the observed driver mutations. In summary, this study demonstrates that radiation emitted by UV-nail polish dryers can both damage DNA and can permanently imprint somatic mutations on the genomes of mammalian cells. These results have far reaching implications in regard to public health and to preventing skin cancer due to occupational- or consumer-based exposure to ultraviolet light from artificial sources.