Treatment of male guinea pigs with the potent chemical carcinogen N-nitrosodiethylamine (NDEA) at an intraperitoneal dose of 40 mg/kg body weight for three consecutive days resulted in a significant decrease in the levels of ascorbic acid in liver, lungs, kidneys, and adrenal glands. The decrease in the brain and plasma was, however, not significant. Radiorespirometric, distribution, and urinary excretion studies conducted with the use of L-[carboxyl-14C ] ascorbic acid revealed that a possible mechanism responsible for depletion of the body ascorbate store by NDEA might be the enhanced metabolic degradation of ascorbic acid into CO2, and other metabolites that are excreted through urine.