Comparative cytotoxicities of selected minor dietary non-nutrients with chemopreventive properties.

The comparative acute cytotoxicities were determined for a varied spectrum of minor dietary non-nutrients that have been implicated as chemopreventive agents. Cytotoxicity was determined with the neutral red (NR) assay, using BALB/c mouse 3T3 fibroblasts as the bioindicators. Based on midpoint cytotoxicity (NR50) values, the range of cytotoxicity for the different chemicals varied by 1000 times. The sequence of potency was tannic acid, tamoxifen citrate, quercetin, benzyl and phenethyl isothiocyanate > glycyrrhetinic acid > indole-3-carbinol > caffeic acid > phytic acid > vanillin > ellagic acid > D-saccharic acid 1,4-lactone. Vanillin, at slight to moderately toxic concentrations, was the only test agent that induced multinucleation in the 3T3 fibroblasts.