Biophysical characterization of skin damage and recovery after exposure to different surfactants

The majority of adverse skin reactions to personal-care products are presumed to be caused by irritant substances, like surfactants. In this study, different aspects of the irritant reaction after a single exposure to 8 surfactants were characterized during 2 weeks. Solutions of 2% sodium lauryl sulfate, 5% sodium C12-15 pareth sulfate, 5% sodium cocoyl isethionate, 10% disodium laureth sulfosuccinate, 10% sodium cocoamphoacetate, 10% cocamide DEA, 10% cocamidopropyl betaine and 10% lauryl glucoside, respectively, were applied to the forearm of 12 volunteers. Clinical assessment, an evaporimeter, a laser Doppler flowmeter and a corneometer were used for evaluation. The surfactants induced different degrees of irritation. Erythema, transepidermal water loss and skin blood flow exhibited a similar time course, which seemed to be inversely related to the delayed scaling and reduced skin capacitance. The mechanism of the damaging effect of the surfactants seems to be similar, although some minor differences were noted.