RESUMO
Irritant skin reactions can be evaluated by several techniques. Using different scores for the degree of erythema, edema, scaling and fissuring is the time-honored approach but implies t,he disadventagrs of lacking objectivity and pararretric properties. This paper describes the objective nteasurement of irritant. skin responses to various concentrations of Sodium Lauryl Sulfate(SLS) and Ethanol by a color reflectance meter(Chroma Meter) and compares with visual scoring The results are summarized as follows : 1. Pretreatment assessments by a Chroma Meter on normal forearm area showed an average score of 7.70+1.53 for Chroma Meter value a*(rediies:; score). 2. Skin responses to SLS in various concentrations of 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 7.5% under occlusion for 24 hours were assessed by visual scoring system. They are measured 0.56+1.10, 0.74+1.29, 1.19 1.36, 2.11+1.69, 2.19+1.91, 2.56+1.50 2.81+2.16 respectively. 3. Skin responses to SLS in various concentrations of 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 7.5% under occlusion for 24 hour were assessed by a Chroma Meter valu a*(redness score). They are measured 8.29+1.98, 8.37+2.47, 9.31+2.27, 10.34+2.97, 10.35+3.18, 10.51+2.47, 11.61+3.45 respectively. 4. Skin responses to Ethanol in various concentrations were nearly negligible. 5. We have demonstrated there is a highly significant correlation between skin redness measured by the Chroma Meter and visually assessed erypthma(p<0.0001). It yields reproducible, objective, quantitative measurements of iryhema that parallel the subjective visual assessments.