Formation and Analysis of Tobacco-Specific N-Nitrosamines
The N-nitrosamines derived from nicotine are the only known tobacco-specific carcinogens in indoor air that is polluted by environmental tobacco smoke. Chemical-analytical studies led to several new observations on the formation of tobacco-specific N-nitrosamines (TSNA) and their occurrence in smokeless tobacco, mainstream smoke (MS), and sidestream smoke of American and foreign cigarettes. The analyses of MS of united states and foreign cigarettes smoked under FTC conditions revealed comparable data for the smoke of nonfilter cigarettes and filter cigarettes except in the case of low- and ultralow-yield cigarettes, which showed reduced TSNA yields. Epidemiological studies in the northern Sudan showed a high risk for oral cancer for users of toombak, a home-made oral snuff. When snuff was extracted by means of supercritical fluid extraction with carbon dioxide containing 10% methanol, analysis of this material confirmed that the extraction with organic solvents had been partially incomplete.