Editor's note: This popular story from the Daily Briefing's archives was republished on Jul. 24, 2023.

A new study published last week in Nature Communications found that regular use of UV-nail polish dryers may increase the risk of skin cancer—but researchers warn that additional data is needed to substantiate their findings. Writing for NPR, Rachel Treisman outlines precautions and alternatives to gel manicures and pedicures.

Study details and key findings

For the study, researchers from the University of California, San Diego (UC) and the University of Pittsburgh tested three different cell types—two from humans and one from mice—that had various levels of exposure to UV lamps.

Under acute exposure, the researchers placed petri dishes in a UV machine for 20 minutes, took them out for an hour, then placed them back in for another 20 minutes. Under chronic exposure, the researchers placed petri dishes in a UV machine for 20 minutes a day for three days.

Researchers found that a single 20-minute session caused 20% to 30% of the exposed cells to die while three consecutive sessions caused 65% to 70% of them to die. In addition, they found that UV exposure resulted in mitochondrial and DNA damage in the surviving cells.

According to Maria Zhivagui, a postdoctoral researcher at UC San Diego and the first author of the study, the UV devices used in nail salons are typically more potent than those used in the study, meaning that even if they are used for a shorter time in the salon than in the lab, the exposure could still be higher.

In particular, Zhivagui, who regularly got gel manicures before the study, said she was concerned by the strength of the results. "When I saw these results, I decided to kind of put a hold on it and just mitigate as much as possible my exposure to these risk factors," she said.

While the study indicates that chronic exposure to UV light damages human cells, it does not conclusively link exposure to an increased risk of skin cancers. However, the study cites previous research that has tied gene mutations to increased cancer risk.

How you can protect your skin from UV exposure

Shari Lipner, a dermatologist and director of the Nail Division at Weill Cornell Medicine, said the study confirms concerns shared by the dermatology community for years.

Because gel manicures are still relatively new—and DNA damage can take years to build up—it is possible that more skin cancer cases associated with UV dryers will surface in the next few years, Lipner said.

"And so what I would recommend is that people who have a long history or regular history of doing the gel nails ... every few weeks for years, they should partner with a board certified dermatologist who can check their skin regularly looking for early signs of skin cancer," Lipner said.

In addition, "[i]f you are going to get a gel manicure, use sunscreen and fingerless gloves; that will certainly add a ton of protection. And maybe if you're going once a month, you can limit that to a few times a year," she added.

Currently, there is not enough data to determine exactly how much UV exposure from nail dryers is too much, but Lipner said people should try to limit their exposure.

In particular, FDA suggests limiting dryer use to 10 minutes per hand and removing any cosmetics, fragrances, and skin care products that can increase your sensitivity to UV rays before exposure.

In addition, experts recommend applying a broad-spectrum sunscreen to the entire area around 20 minutes before UV exposure. According to Lipner, a broad-spectrum sunscreen with SPF 30 or higher is best. Experts also suggest investing in a pair of fingerless, UV-absorbing gloves that only leave your nails uncovered.

"I think even before the study, that was the way to go," Lipner said. "And in light of the study, I think it should convince people even more to use caution."

For people that do not want any exposure to UV dryers, there are alternative gel nail polish options. For example, some companies make long-lasting, fast-drying gel polish that does not need to be dried under a UV light. There are also long-lasting dip powders that are applied directly to the nail and air dry. People can also opt for regular nail polish.

According to the Skin Cancer Foundation, the safest option is to use an air blower or fan to dry your nails or let them air dry without additional tools. (Treisman, NPR, 1/26)