Evaluation of Ocular Irritancy of Hair Care Products

Abstract

Four hair care products—dandruff shampoo, baby shampoo, and experimental formulations designated I and II—were evaluated for ocular irritancy by Draize testing, biomicroscopic examination, measurement of corneal thickness, and analysis of effects on cell migration rate during healing following topical application. The goal of the study was to determine the utility of a new statistical method for analysis of Draize data, known as time-weighted averaging, and to determine whether increasing the degree of ethoxylation of the surfactant ammonium lauryl ether sulfate (ALES) from 1 mole (formulation I) to 3 moles (formulation II) reduces ocular irritancy. The results of analyses by each method were in agreement, with dandruff and baby shampoos rated as severe and nonirritants, respectively. The experimental formulations were intermediate to these extremes and, based on time-weighted average Draize scores and cell migration rate (40 µm/hr formulation I, 67 µm/hr formulation II, 72 µm/hr control), it is concluded that increasing the degree of ethoxylation of ALES reduces the irritancy and toxicity of a shampoo.