Alternative method for checking toxicity of hair dyes.

Synopsis We have compared the in vitro and in vivo toxicities of 19 hair dyes. In vitro, the toxic effect was estimated in Chinese hamster lung fibroblasts (V79), using a cell growth inhibition test. For each compound, the concentration required to reduce 50% of the growth (CI(50)) was determined. In vivo, compounds were administered by i.p. route to groups of 10 Swiss mice per dose. The LD(50) values obtained were used to estimate the acute toxicity. The comparison of the results in vivo and in vitro showed that there is a good correlation between both ranking orders (correlation coefficient r= 0.90 with a first kind error P= 10(-4)). These results suggest that the use of cell culture tests is valuable as pre-screening systems to appreciate the toxicity level of hair dyes, in order to reduce the use of animals in safety evaluation.