Distribution of Radioactivity Following Oral Administration of Carcinogenic super(14)CH sub(3)-Labelled Nitrosocarbaryl in the Rat

After a single intragastric administration of super(14)C-labelled carcinogenic nitrosocarbaryl, a nitrosated pesticide, the distribution of radioactivity was investigated in the blood and a number of organs in male rats. The greatest amount of the super(14)CH sub(3) - group was associated with the forestomach, tumor-susceptible tissue; the level of radioactivity is noteworthy but less important in the glandular stomach. There are also sites of radioactivity accumulation mainly in the liver. Moreover, ( super(14)C)nitrosocarbaryl was revealed in the blood suggesting that nitrosamine itself rapidly (0.5 h) crosses the intestinal barrier and in a significant quantity (13%). These facts constitute a potential carcinogenic risk.