Regular Article :AATEX 3(4):182-190
Cytotoxicity tests using SIRC cells and crystal violet (CV) staining or neutral red (NR) uptake as their endpoints were primarily validated using nine surfactants and physiological saline by six and seven laboratories. respectively, under the Ministry of Health and Welfare (MHW) project on alternatives, to the Draize rabbit eye irritation test (Draize test) for cosmetic ingredients. The inter-laboratory coefficient of variation of EC50s of the test substances by CV staining and the NR uptake method were 0.262 and 0.304, respectively. These two endpoints gave similar EC5050s and the correlation coefficient between them was high (r=0.996) Correlation coefficients between maximal average Draize total scores (MAS) of test substances in Draize tests and their EC50s in CV staining and NR uptake were -0.894 and -0.913, respectively.
From these results, we concluded these cytotoxicity tests using SIRC cells are promising as alternative methods to the Draize test for cosmetic ingredients, and the CV staining and NR uptake methods gave almost identical results. However, further validation of these methods is needed using a wider range of cosmetic ingredients.
Key words: validation study, Draize eye irritation test, alternative, in vitro, cytotoxicity test, SIRC cell line, crystal violet, neutral red, surfactant.