Comparison of Three In Vitro Assays to Determine the Ocular Toxicity of Detergent, Oil, and Organic Solvents

Abstract

The cytotoxicity of 39 chemicals, including detergents, oils, and organic solvents, previously reported in neutral red (NR) assay was further evaluated using Chinese hamster lung fibroblast V79 cells, primary rabbit corneal (RC) cells, and normal human epidermal keratinocytes (NHEK). Cationic detergents were most toxic in each cell types. Glycols and oils showed weak toxicity. NHEK cells showed higher sensitivity than other cell types. A good correlation was observed between in vitro cytotoxicity (IC50) and the eye irritation index (DS20 value) produced in the in vivo Draize test. Correlation coefficients were V79 cells vs. DS20: r = 0.93; RC cells vs. DS20: r = 0.92; and NHEK vs. DS20: r = 0.90. There was little difference in the predictability of eye irritancy of chemicals among three cell types. The NR cytotoxicity assay using V79 cells is useful for screening eye-irritating chemicals.