Group Award for Leveraging Activities - 2001 FDA Science Forum

Board B05

We are studying UV-induced erythema in a cohort of 110 volunteers divided into 11 groups on the basis of their skin type (Fitzpatrick, 1-6) and their racial/ethnic origin (OMB classification 0990-0208: American Indian or Alaska Native; Black or African American; Asian; Hispanic or Latino; Native Hawaiian or Other Pacific Islander; White.) Small areas on the backs of the subjects are exposed to different doses of UV radiation from FS lamps. After 1, 2, 8, and 16 days, skin color changes are evaluated visually and instrumentally with a Minolta spectrophotometer and a DiaStron Erythema/Melanin Meter. The first instrument takes measurements at 10-nm intervals (400700 nm), the second one at 546, 632, and 905 nm. Until now, the data have been collected on 52 subjects. Administered doses ranged from 72 to 3333 J/m² (CIE Erythema Action Spectrum weighted at 298 nm). The sensitivity of the visual and instrumental observations is similar, although in some cases erythema can be measured instrumentally in the exposed areas that are not easy to evaluate visually. Results confirm wide variation of the Minimal Erythema Doses (MED) within skin types. For example, for the subjects with a skin type 2/2.5, and 3/3.5 the MED ranged from 171-400 and 150-709 J/m², indicating significant overlap.