Ammoniated glycyrrhizin, butylated hydroxytoluene, and gum Arabic are "generally recognized as safe" (GRAS) substances that are used primarily as additives in foods. These substances were incorporated into rodent diets and fed to male rats and mice for 10 and 8 wk, respectively. The treated male mice and rats were then tested for dominant lethal effects. The mice were also tested for induced heritable translocation. Results of the rat studies indicated a statistically significant dominant lethal effect of each of the compounds tested; however, the biological significance of this response is not known. Results of the mouse dominant lethal and heritable translocation studies, on the other hand, indicated no adverse effects of the compounds tested.