A test of the mutagenicity of cooked meats in vivo

There is a correlation between intestinal cancer and diets high in meat, so fried beef, chicken, lamb, pork and fish were tested for their ability to induce mutations in the small intestine of mice, The mice were bred to be h eterozygous at the Dlb-1 locus so that loss of the dominant Dlb-1(b) allele by mutation could be detected, Mice were fed the AIN-76A diet (which conta ins 50% of the calories in the form of sucrose) or an isocaloric diet in wh ich the sucrose was replaced by meat or fish, for 5 or 9 weeks, Manifestati on of mutants requires similar to1 week in this system, so this corresponds to an effective exposure of 4 and 8 weeks, respectively, There was no sign ificant difference in the weights of animals on the different diets, and no difference in mutant frequency. Several food mutagens were present, but at low levels. These results, when considered in the light of tests of 2-amin o-1-methyl-6-phenylimidazo[4,5-b] pyridine and amino(alpha )carboline at mu ch higher doses (Zhang,X,-B, Tao,K.S,, Urlando,C., Shaver-Walker,P, and Hed dle,J,A, (1996) Mutagenesis, 11, 43-48), indicate that there is no highly m utagenic compound missed by previous testing with bacterial assays and that mixtures of heterocyclic amines at low levels do not show great synergy.