Evaluation of the EpiOcular((TM)) Tissue Model as an Alternative to the Draize Eye Irritation Test

Cosmetic ingredients were tested to determine the ability of the EpiOcular(TM) tissue model to predict eye irritation potential. In vitro results were compared with historical Draize eye irritation records. Forty-three samples, consisting of 40 cosmetic raw ingredients of different type and physical form (i.e. liquids, powders, gels) were evaluated. Using the MTT cytotoxicity assay, an ET(50) value (effective time of exposure to reduce tissue viability to 50%) was determined for each sample. ET(50) values were categorized into four irritation groups: (a) non-irritating/minimal; (b) mild; (c) moderate; or (d) severe/extreme. Comparison of in vitro EpiOcular(TM) and in vivo Draize classifications showed that 63% (27 of 43 samples) were classified identically. Assay performance improved to 95% (41 of 43 samples) with the addition of samples overpredicted by a single irritation class. This evaluative exercise represents a conservative safety assessment. There were no underpredictions of eye irritation for any material in this study. Based on these results, use of the EpiOcular(TM) tissue model shows promise as an in vitro assay to assess the ocular irritation potential of cosmetic ingredients.