Human fecal fractions can produce nuclear damage in the colonic epithelial cells of mice.

Nuclear toxicity of several known carcinogens and fecal fractions obtained from 10 healthy individuals was investigated in the colonic nuclear aberration (NA) assay using an intrarectal administration. Two known colon carcinogens, MNNG and DMAB, and a carcinogen of organs other than the colon, B(a)P, induced NA in a dose-related manner. Chromatographic fractions of feces from 10 donors were tested for their ability to produce NA. The dichloromethane fraction for several was active and yielded a significantly positive response which was dose-related. Our study demonstrated that the feces of some healthy individuals contain compound(s) which damage colonic nuclei in a similar manner to that seen with some known carcinogens.