2-Naphthylamine, 4-Aminobiphenyl, Benzene, Vinyl Chloride, Ethylene Oxide, Arsenic, Beryllium, Nickel, Chromium (only hexavalent), Cadmium, and Polonium-210 are human carcinogens found in tobacco smoke.
"Smoking and Tobacco Control." U.S. Department of Health and Human Services, Public Health Service, National Institutes of Health, National Cancer Institute. Bethesda, MD. Risks Associated with Smoking Cigarettes with Low Machine-Measured Yields of Tar and Nicotine. 19 Nov. 2001: 176-80.http://cancercontrol.cancer.gov/brp/tcrb/monographs/13/m13_complete.pdf