AN ANALYSIS OF UVA EMISSIONS FROM SUNLAMPS AND THE POTENTIAL IMPORTANCE FOR MELANOMA

Exposure to solar UV radiation is a risk factor for cutaneous malignan t melanoma (CMM), Epidemiologic studies have also considered the use o f sunlamps as a possible contributor to CMM. We measured and analyzed the emission spectra of six different currently marketed sunlamps and a historical sunlamp, the UVB-emitting FS lamp, and compared the resul ts to solar exposure. For a typical tanner (20 sessions @ 2 minimal er ythema doses (MED)/session), the annual WA doses from commonly used fl uorescent sunlamps were 0.3-1.2 times that received from the sun. For a frequent tanner (100 sessions @ 4 MED/session), the annual UVA doses from fluorescent sunlamps were 1.2-4.7 times that received from the s un and 12 times for recently available, high-pressure sunlamps. To det ermine biologically effective doses, action spectra for squamous cell carcinoma (SCC) in humans and for melanoma in the Xiphophorus fish (XF M) were applied to the sunlamps' emission spectra, The results for the effective doses using the SCC action spectrum tracked the UVB doses, while the results using the XFM action spectrum tracked the WA doses. When combined with UV exposure received from the sun, typical sunlamp use results in an approximate doubling of annual effective dose, if th e XFM action spectrum is applied. Frequent use, however, can increase the annual effective XFM dose by as much as 6 times what would be rece ived from the sun alone for fluorescent sunlamps and as much as 12 tim es for newer, high-pressure sunlamps.