iHeard... that the UV lights used in nail salons for Shellac and other nail polishes cause skin cancer."
Lamps that emit ultraviolet (UV) radiation are standard in some nail salons to speed-dry regular manicures and to set gel manicures. These lamps can be called UV lamps or LED lamps and both emit UV radiation, predominantly UVA rays which have been linked to increased risk of skin cancer. We have good evidence of the level of risk from the sun and sources such as solariums (commercial use was banned in Australia in 2016) but we don’t have strong research about devices used in nail salons. Generally UV and LED lamps emit low levels of radiation and exposure times are short.
If you are concerned, apply a broad spectrum SPF30 (or higher) sunscreen to your hands 20 minutes before they are exposed to UV light or use fingerless gloves - many salons now offer these.
Remember, the greatest risk of skin cancer comes from over-exposure to UV radiation from the sun. Whenever the UV is 3 or higher, use five forms of sun protection: Slip on clothing, Slop on SPF 30 or higher sunscreen, Slap on a broad-brim hat, Seek shade and Slide on sunglasses.