title: Tobacco-Specific Nitrosamines in the Tobacco and Mainstream Smoke of U.S. Commercial Cigarettes.
abstract: Tobacco-specific nitrosamines (TSNAs) are N-nitroso-derivatives of pyridine-alkaloids (e.g., nicotine) present in tobacco and cigarette smoke. Two TSNAs, N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), are included on the Food and Drug Administration's list of harmful and potentially harmful constituents (HPHCs) in tobacco products and tobacco. The amounts of four TSNAs (NNK, NNN, N-nitrosoanabasine (NAB), and N'-nitrosoanatabine (NAT)) in the tobacco and mainstream smoke from 50 U.S. commercial cigarette brands were measured from November 15, 2011 to January 4, 2012 using a validated HPLC/MS/MS method. Smoke samples were generated using the International Organization of Standardization (ISO) and Canadian Intense (CI) machine-smoking regimens. NNN and NAT were the most abundant TSNAs in tobacco filler and smoke across all cigarette brands, whereas NNK and NAB were present in lesser amounts. The average ratios for each TSNA in mainstream smoke to filler content is 29% by the CI smoking regimen and 13% for the ISO machine-smoking regimen. The reliability of individual TSNAs to predict total TSNA amounts in the filler and smoke was examined. NNN, NAT, and NAB have a moderate to high correlation (R2= 0.61-0.98, p < 0.0001), and all three TSNAs individually predict total TSNAs with minimal difference between measured and predicted total TSNA amounts (error < 7.4%). NNK has weaker correlation (R2= 0.56-0.82; p < 0.0001) and is a less reliable predictor of total TSNA quantities. Tobacco weight and levels of TSNAs in filler influence TSNA levels in smoke from the CI machine-smoking regimen. In contrast, filter ventilation is a major determinant of levels of TSNAs in smoke by the ISO machine-smoking regimen. Comparative analysis demonstrates substantial variability in TSNA amounts in tobacco filler and mainstream smoke yields under ISO and CI machine-smoking regimens among U.S. commercial cigarette brands.
authors.affiliation: Center for Tobacco Products, Food and Drug Administration , Silver Spring, Maryland 20850, United States.
authors.forename: Selvin H
authors.initials: SH
authors.lastname: Edwards
authors.affiliation: Center for Tobacco Products, Food and Drug Administration , Silver Spring, Maryland 20850, United States.
authors.forename: Lana M
authors.initials: LM
authors.lastname: Rossiter
authors.affiliation: Center for Tobacco Products, Food and Drug Administration , Silver Spring, Maryland 20850, United States.
authors.forename: Kenneth M
authors.identifier: 0000-0002-5130-5758
authors.initials: KM
authors.lastname: Taylor
authors.affiliation: Center for Tobacco Products, Food and Drug Administration , Silver Spring, Maryland 20850, United States.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Holman
authors.affiliation: Centers for Disease Control and Prevention, National Center for Environmental Health , Atlanta, Georgia 30341, United States.
authors.forename: Liqin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Centers for Disease Control and Prevention, National Center for Environmental Health , Atlanta, Georgia 30341, United States.
authors.forename: Yan S
authors.initials: YS
authors.lastname: Ding
authors.affiliation: Centers for Disease Control and Prevention, National Center for Environmental Health , Atlanta, Georgia 30341, United States.
authors.forename: Clifford H
authors.initials: CH
authors.lastname: Watson
mesh_terms: D002273:Carcinogens / Q000032:analysis; D002853:Chromatography, Liquid; D009602:Nitrosamines / Q000032:analysis*; D012906:Smoke / Q000032:analysis*; D053719:Tandem Mass Spectrometry; D014481:United States; D014026:Nicotiana
chemical_list: D002273:Carcinogens; D009602:Nitrosamines; D012906:Smoke