Establishment of a strategy using alternative methods to the use of animals to evaluate the ocular irritant potential of cosmetics for styling, braiding, or fixing hair

Assessing the safety of cosmetic products requires rigorous analysis before marketing, with emphasis on the potential for ocular irritation, given the sensitivity of the eye and the complexity of the toxicological mechanisms involved. Ocular irritation is a complex process involving multiple toxicity mechanisms; alternative methods can be combined within a testing strategy for a complete prediction of ocular safety. This study proposed a sequential testing strategy to assess the irritating potential of hair pomades, products widely used for hair styling but associated with adverse ophthalmological effects such as edema, burns, and transient vision loss. A bottom-up approach was adopted, starting with the HET-CAM assay, selected for its sensitivity, reproducibility, and applicability in the initial screening of nonirritating substances. Next, the SkinEthic™ Reconstructed Cornea model was applied, which mimics the histological and biochemical characteristics of the human corneal epithelium and constitutes the only alternative method validated as a complete replacement for the Draize Test. The results demonstrated strong agreement between the methods: negative samples in HET-CAM were confirmed by SkinEthic™, indicating that the former can reliably predict the absence of ocular irritation. This sequential strategy optimizes resources, reduces costs, accelerates safety assessment, and contributes to the application of the 3Rs in ocular toxicology.