By Doug Schoon, president, Schoon Scientific
What started the controversy about nail lamps in the first place? In 2009, two dermatologists from sunny Texas (MacFarlane and Alonso1) claimed that the nonmelanoma skin cancers on two patients’ hands may have been caused by UV nail lamps. Their flawed rationale was based on ignorance of UV sources. They incorrectly compared UV nail lamps to tanning beds, based solely on wattage vs. area of exposed skin, which completely ignores the importance of the irradiance of the UV wavelengths emitted and length of exposure. Both are critical for making proper safety determinations.
Oddly, one patient was a 48-year-old woman who had only been to the nail salon eight times over the course of the year and, according to these dermatologists, had pre-existing “moderate recreational exposure” to sunlight. These dermatologists jumped to incorrect conclusions, despite having no evidence to support their misguided suspicions. Not surprisingly, the news media ran hard with the story. The media began a long and relentless attack on salons that continues to this day. Naysayers remain in steadfast denial about the safety of UV nail lamps, despite straightforward evidence of safety.
Now the US Food and Drug Administration (FDA) has recognized what scientific researchers have been saying for many years: UVA nail lamps are safe as used in nail salons. In July 2017, the FDA released a statement which, in part, states, “…the FDA views nail curing lamps as low risk when used as directed by the label. For example, a 2013 published study indicated that – even for the worst-case lamp that was evaluated – 36 minutes of daily exposure to this lamp was below the occupational exposure limits for UV radiation. (Note that these limits only apply to normal, healthy people and not to people who may have a condition that makes them extra sensitive to UV radiation.) To date, the FDA has not received any reports of burns or skin cancer attributed to these lamps.
The FDA was referring to a 2013 study, “Photobiological Safety Evaluation of UV Nail Lamps,” authored by two world-class photobiologists, Drs. John Dowdy and Robert Sayre.2 Unlike previous studies, their research adhered exactly to the ANSI/IESNA RP-27 standard and utilized an appropriate research-grade spectrophotometer. They reported that nail lamp outputs ranged from 0.5% to 2.2% of the allowable monthly occupational exposure limits, according to the authors, or 0.30 to 1.676 µW/cm2 between the range of 350 to 400 nm.
The study provides conclusive evidence to demonstrate that MacFarlane and Alonso were incorrect and UV nail lamps are not like tanning beds, as confirmed by Dowdy and Sayre. “When UV nail lamps evaluated in this report are compared together with these earlier sunlamp computations, we find that the UV nail lamps are vastly less hazardous.”
Not only does this study provide evidence that UV nail lamps are safe as used in nail salons, Dowdy and Sayre found the UV nail lamps were even safer than they expected. “All of the various UV nail lamps submitted for evaluation were found to be significantly less hazardous than might have been anticipated based on the initial concerns raise…”
Their paper cited research demonstrating the natural nail plate is a very efficient blocker of UV, protecting the nail bed: “…the UV exposure risk to the nail bed is comparable to that of skin protected by high SPF topical sunscreen.” According to the authors, the nail plate’s natural UV resistance is comparable to the UV resistance provided by an SPF 40 sunscreen.
Also cited was additional research to demonstrate that the backside of the hand is 4 times more resistant to UV than the forehead or cheek and 3.5 times more resistant than a person’s back, making the backside of the hand the most UV-resistant part of the body.
Since the measured UV exposure is so low, a person could go to the workplace and once every day put a hand under a UV nail lamp for 36 minutes – and this still would be within the permissible daily occupational exposure limits for workers, according to the applicable international standard (ANSI RP-27). Obviously, salon client exposure is much lower – a tiny fraction in comparison. Client exposure is only twice per month, ranging from two to 10 minutes. Because both fluorescent tube and LED-style nail lamps were studied, this provides powerful evidence to support the safety of UV nail lamps.
This study also demonstrates that risks for development of nonmelanoma skin cancer (NMSC) are very low when compared to risks provided by normal noon sunlight. Of the types of UV that can cause NMSC, the Dowdy/Sayre study found “…the UV nail lamps had 11 to 46 times less NMSC effective irradiance than an overhead 1 atmosphere solar spectrum [normal noon sunlight].”
These researchers put things into perspective when they concluded that it is very unlikely that anyone could become overexposed to UV through normal use of the nail lamps tested, since they considered it “…highly improbable that even the most dedicated nail salon client or avid home user would approach this level of exposure.
When sharing his opinions about the test results, Dr. Sayre said that some physicians “are grossly exaggerating exposures.” And of UV nail lamps he says, “…this UV source probably belongs in the least risky of all categories. UV nail lamps are safer than natural sunlight or sunlamps.”
A second study from medical researchers Markova and Weinstock of Massachusetts General Hospital and the Alpert Medical School at Brown University also confirm the safety of these lamps. The study states conclusively, “UV nail lamps do not appear to significantly increase lifetime risk…”3
Also noted in this study is that doctors often use UV medical lamps as a therapeutic skin treatment and, when compared to such medical devices that have been in long use, one would need over 250 years of weekly UV nail sessions to experience the same risk exposure.
The authors concluded, “Dermatologists and primary care physicians may reassure patients regarding the safety of these devices.”
These two studies confirm the original statements released after the Nail Manufacturers Council on Safety (NMC) of the Professional Beauty Association concluded its initial study in 2009, which claimed the lamps are safe when used as directed. Unfortunately, some misinformed individuals have ignored the body of evidence that has all along demonstrated that UV nail lamps are safe as used in salons. These uninformed opinions have created significant problems for nail technicians by needlessly alarming and frightening away many potential clients.
We can’t change the past, but we can join forces and proactively work together to ensure the facts are made known. Now the FDA has weighed in on the matter, perhaps the misinformed naysayers will be silenced.
- MacFarlane, D.F., Alonso, C.A. (2009) Occurrence of nonmelanoma skin cancers on the hands after UV nail light exposure. Arch Dermatol 145:447-9.
- Dowdy, J.C.; and Sayre, R.M. (2013), Photobiological Safety Evaluation of UV Nail Lamps. Photochemistry and Photobiology, 89: 961967. doi: 10.1111/php.12075
- Markova, A.; Weinstock, M.A. (2012) Risk of Skin Cancer Associated with the Use of UV Nail Lamp. J Invest Dermatol
Doug Schoon is an internationally-recognized scientist, author and educator with more than 30 years’ experience in the cosmetic, beauty and personal care industry. He is a leading authority known for both his scientific and regulatory work and has been awarded 17 patents for innovative cosmetic products. He is president of his own company, Schoon Scientific, and he served for 21 years as the co-chair of the Nail Manufacturers Council on Safety (NMC) under the Professional Beauty Association and for 20 years as CNDs vice president of Science and Technology. Schoon has authored several books, video and audio training programs, as well as hundreds of articles about salon products, safety and best practices for salon professionals. Schoon serves as an expert witness in legal cases involving cosmetic regulations, formulations and safety.