Tanning: The Risks of Ultraviolet Rays

Sunlamps and tanning beds promise consumers a bronzed body year-round, but the ultraviolet (UV) radiation from these devices poses serious health risks.

“Although some people think that a tan gives them a ‘healthy’ glow, any tan is a sign of skin damage,” says Sharon Miller, M.S.E.E., a Food and Drug Administration (FDA) scientist and international expert on UV radiation and tanning.

“A tan is the skin’s reaction to exposure to UV rays,” says Miller. “Recognizing exposure to the rays as an ‘insult,’ the skin acts in self-defense by producing more melanin, a pigment that darkens the skin. Over time, this damage will lead to prematurely aged skin and, in some cases, skin cancer.”

Two types of UV radiation that penetrate the skin are UV-B and UV-A rays.

* UV-B rays penetrate the top layers of skin and are most responsible for sunburns.
* UV-A rays penetrate to the deeper layers of the skin and are often associated with allergic reactions, such as a rash.

Both UV-B and UV-A rays damage the skin and can lead to skin cancer. Tanning salons use lamps that emit both UV-A and UV-B radiation.
Cancer Risk

Exposure to UV radiation—whether from the sun or from artificial sources such as sunlamps used in tanning beds—increases the risk of developing skin cancer, according to the National Cancer Institute (NCI). Melanoma, the deadliest form of skin cancer, is linked to getting severe sunburns, especially at a young age.

In July 2009, the International Agency for Research on Cancer (IARC), part of the World Health Organization, concluded that tanning devices that emit UV radiation are more dangerous than previously thought. IARC moved these devices into the highest cancer risk category: “carcinogenic to humans.” Previously, it had categorized the devices as “probably carcinogenic to humans.”

Development of cancer is a long process that may take decades. Therefore, IARC also recommended banning commercial indoor tanning for those younger than 18 years to protect them from the increased risk for melanoma and other skin cancers.

IARC’s conclusions and recommendations were based on its 2006 review of 19 studies conducted over 25 years on the use of indoor tanning equipment. The review found evidence of

* an association between indoor tanning and two types of skin cancer: squamous cell carcinoma and melanoma
* an association between UV-emitting tanning devices and cancer of the eye (ocular melanoma)
* both UV-A and UV-B rays causing DNA damage, which can lead to skin cancer in laboratory animals and humans
* the risk of melanoma of the skin increasing by 75 percent when tanning bed use started before age 35

IARC’s review had some limitations, says Ron Kaczmarek, M.D., M.P.H., an FDA epidemiologist who analyzed the review. Limitations include possible inaccuracy of people’s memories of their tanning experiences, not knowing the amount of UV radiation emitted by each tanning device, and the inability to separate the effects of individuals’ indoor and outdoor exposure. Nevertheless, IARC concluded that there is convincing evidence of an association between the use of indoor tanning equipment and melanoma risk, and that the use of tanning beds should be discouraged.

“It’s well established that UV radiation from the sun causes skin cancer,” says Miller. “Since lamps used in tanning beds emit UV radiation, the use of indoor tanning devices also increases your risk of skin cancer.”