Prediction of the eye irritation potential of shampoos using the in vitro SIRC cell toxicity test

Shampoos predicted to vary over a wide range in their potential to cause eye irritancy were tested in SIRC rabbit corneal cells for cytotoxicity. Six shampoos at at least ten different concentrations were added to culture dishes containing the SIRC cells and were administered at a dose of 0.01 ml directly to the corneal surface of the albino rabbit eye. When the shampoos were ranked both according to their relative toxicities in vitro and according to their relative irritancies in the modified Draize test the resulting rank orders were in perfect agreement. The results demonstrate that the SIRC cell line is a suitable model system for screening shampoos of differing surfactant compositions without the need to use live animals. Further, results obtained from the SIRC cell assay should aid in the selection of final product formulations for in vivo testing as part of the pre-market clearance process.