Abstract:

Cleansers are essential daily basic cosmetics, and these products contain a high level of surfactants, which have a certain degree of eye irritation. When evaluating the eye irritation of cosmetics using the Draize test, such samples can cause hyperemia and edema of conjunctiva and changes of cornea opacity of rabbits. In order to reduce the harm to rabbits, an in vitro evaluation method was established. BioOcullar^® is the first commercially available reconstructed human cornea-like epithelium model developed by a Chinese company. This model has been identified as a useful tool for the testing of irritancy. The test protocol has also been developed for chemicals. However, this protocol is not suitable for cosmetic formulations, therefore in this study a method for evaluating the eye irritation of cleansers was established based on BioOcullar^®. The chemicals under test were applied to three tissues, and the tissue viability was measured after exposure and a post-treatment incubation period. Firstly, the exposure time and post-incubation time should be optimized according to the barrier function of the tissue. Secondly, the acceptance criteria should also be considered. Three batches of cleansers with known irritation （Draize test） were used to explore the relevant conditions of the method and to select the appropriate exposure time and post-treatment incubation period. The results showed that, 60 min of exposure was the most suitable, and the presence of post-treatment incubation period could reduce the sensitivity of the method. Another 12 batches of cleansers with known irritation （Draize test） were used to validate the method and determine the criteria. According to the evaluation results for three times, the acceptance criteria were: no irritation: viability≥60%; mild irritation: 15%≤viability<60%; irritation: viability<15%. Finally, the method was used to predict 12 batches of cleansers with unknown irritation and compared with the results of the Draize test with an in vitro/in vivo agreement rate of 91.7% （11/12）. The results indicate that the evaluation method established in this study can differentiate the eye irritation of cleansers.

Key words: cleanser, eye irritation, BioOcullar^®