Objective measurement of surfactant irritation by fiber optic spectroscopy.

Erythema caused by occlusion of 3 concentrations of surfactant was quantified in vivo using a modified spectrophotometer. Standard chamber irritation test sites were evaluated objectively using the spectrophotometer and subjectively by trained observers. There was a good relationship between the instrumental and visual evaluations. The spectrum was analyzed and a region was chosen to optimize the sensitivity of the method.