Oxidative Metabolism of Nicotine by Cigarette Smokers With Cancer of the Urinary Bladder

Summary

Nicotine and its major basic metabolites, cotinine and nicotine-1′-N-oxide, were measured in 24-hour urine collections from normal healthy male cigarette smokers and cigarette smokers with cancer of the urinary bladder. Analysis of replicate daily urine samples from some subjects showed the metabolite ratio cotinine/ nicotine-1′-N-oxide to be an individual index of the alternate routes of oxidative metabolism of nicotine, despite variations in urinary pH, volume, and daily nicotine intake. The ratio of cotinine to nicotine-1′-N-oxide was significantly higher in cancer patients than in the control group. The implication of this finding in relation to the etiology of the disease and the metabolism of nicotine by alternate oxidative pathways in man was discussed.