Chemical characterization of smokeless tobacco products and relevant exposures in users

Abstract Smokeless tobacco (ST) products are characterized by enormous diversity of types and formulations. Many are made with complex mixtures of ingredients and processes that can modify tobacco addictiveness, toxicity, and carcinogenicity. Data on biomarkers of exposure provide important information on the intake of chemical toxicants and carcinogens from the use of ST. Therefore, chemical characterization of ST products and related exposures in users is key to understanding the toxic and carcinogenic potential of ST and development of preventive measures. This chapter provides an overview of sources, levels, and variation of harmful constituents in ST products, relevant biomarkers to assess users' exposure to these constituents, and analytical methods for the measurement of constituents and biomarkers in ST studies. Variations in the levels of key harmful constituents across ST products and the impact of these variations on related exposures are emphasized, and policy implications of such variations are discussed.