Strategies for the evaluation of the eye irritation potential of different types of surfactants and silicones used in cosmetic products

The ocular irritation potential of products that may come into contact with the eyes should be assessed by the combination of different in vitro alternative methods to determine different mechanisms of toxicity previously evaluated by the Draize in vivo assay. Thus, this study proposed to apply two strategies for the prediction of the eye irritation potential of different concentrations of surfactants and silicones, the first one involving evaluation Hen's Egg Test - Chorioallantoic Membrane (HET-CAM), and the other one using Bovine Corneal Opacity and Permeability (BCOP) followed by histopathological. HET-CAM was considered important in assessing the ocular irritation potential and, despite classifying almost all surfactants as "severe irritants", it could discriminate moderate and slight irritant SLES concentrations as well as Cocoamidopropyl Betaine as a severe irritant, when the coagulation score was taken into consideration. The BCOP assay alone also did not offer a good prediction of the irritant potential of surfactants, since almost all of them were classified as "no prediction can be made". However, the histopathological evaluation of the BCOP corneas was very important for establishing the degree and depth of damage related to reversibility. The present study also showed those strategies are sensitive to small variations in the studied anionic, cationic amphoteric surfactant concentrations and can be used for predicting their toxicity in the final product and can be used depending on the focus of the analysis.