Study on the prediction of human lip irritation from cosmetics materials using HeLa-MTT assay

The irritation of cosmetics and their ingredients on lips has mostly been estimated by using human lips. However, human tests are a heavy burden on subjects, making it difficult to evaluate multiple samples. Therefore, it was examined whether the HeLa-MTT assay, which is used as a substitution method for eye irritation test, could be used as a method for evaluating the irritation on lips. Oils and waxes that are well used in lipsticks were selected as samples. For evaluating them, HeLa-MTT assay and human test were performed. The results were compared and a weak correlation was observed between the result from HeLa-MTT assay and the result from human test. This result suggests a possibility that a lip irritation from materials can be predicted by the HeLa-MTT assay.