Back in October 31, 1997, an advisory group reviewing data on substances thought to be carcinogens, recommended that ultraviolet light -- whether from sunlight or an artificial source such as tanning booths and tanning beds -- be listed as "known to be a human carcinogen."

The review panel of the National Toxicology Program's Board of Scientific Counselors approved the listing unanimously recently. This recommendation had also been approved in two earlier scientific reviews.  

The draft document said human studies have shown exposure to solar radiation is causally related to skin cancer and use of sunlamps or sunbeds is associated with skin and eye cancer. While sunlight has long been linked to skin cancers, including sometimes-fatal malignant melanoma, this recent recommended designation makes clear sunlamps, tanning booths and other artificial sources of UV light are also hazardous, regardless of the claims of operators. Up to 10 percent of Americans -- mostly young women -- were estimated during today's discussion to have used artificial tanning devices.

The discussion document also said an estimated half a million welders in the United States are the largest occupational group exposed to artificial ultraviolet radiation. This results from their use of electric arc welding equipment.