title: Carcinogenic tobacco-specific N-nitrosamines in US cigarettes: three decades of remarkable neglect by the tobacco industry.
abstract: BACKGROUND
  Modification of tobacco curing methods and other changes in cigarette manufacturing techniques could substantially reduce the levels of tobacco-specific nitrosamines (TSNA), a group of potent carcinogens, in cigarette smoke. In 1999, two major US cigarette manufacturers stated their intent to move towards using tobaccos low in TSNA. There is no information available on current TSNA levels in tobacco of various cigarettes available in the US, particularly in the newer varieties introduced over the past decade.
  
  
  METHODS
  Seventeen brands of cigarettes were purchased in April of 2010 from retail stores in Minnesota. TSNA levels were measured in the tobacco filler and smoke of these cigarettes.
  
  
  RESULTS
  In all brands, the sum of two potent carcinogenic TSNA--4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and N'-nitrosonornicotine--in cigarette filler averaged 2.54 (± 1.05) μg/g tobacco. This value is virtually identical to the sum of these two carcinogens reported for the tobacco of a US filtered cigarette in 1979. TSNA levels in smoke positively correlated with those in tobacco filler of the same cigarettes.
  
  
  CONCLUSIONS
  We found no indication that any meaningful attempt was made to reduce or at least control TSNA levels in the new varieties of the popular brands Marlboro and Camel introduced over the last decade. In light of the recently granted regulatory authority to the FDA over tobacco products, regulation of TSNA levels in cigarette tobacco should be strongly considered to reduce the levels of these potent carcinogens in cigarette smoke.
authors: Masonic Cancer Center and Tobacco Use Research Programs, University of Minnesota, Minneapolis, Minnesota 55455, USA. stepa011@umn.edu
authors: Irina
authors: I
authors: Stepanov
authors: Aleksandar
authors: A
authors: Knezevich
authors: Liqin
authors: L
authors: Zhang
authors: Clifford H
authors: CH
authors: Watson
authors: Dorothy K
authors: DK
authors: Hatsukami
authors: Stephen S
authors: SS
authors: Hecht
references: Cancer Lett. 1983 Jan;17(3):339-46
references: 6831390
references: Cancer Causes Control. 2011 Jan;22(1):13-22
references: 20967496
references: Cancer Res. 2009 Apr 1;69(7):2990-5
references: 19318550
references: Tob Control. 2004 Mar;13(1):13-6
references: 14985588
references: Cancer Res. 1979 Jul;39(7 Pt 1):2505-9
references: 445452
references: Nicotine Tob Res. 2005 Jun;7(3):443-51
references: 16085512
references: J Natl Cancer Inst. 1977 Jun;58(6):1841-4
references: 864762
references: Cancer Surv. 1989;8(2):273-94
references: 2696581
references: Carcinogenesis. 1990 May;11(5):723-30
references: 2335004
references: J Natl Cancer Inst. 1999 Jul 21;91(14):1194-210
references: 10413421
references: Nicotine Tob Res. 2003 Jun;5(3):323-31
references: 12791527
references: Public Health Rep. 2008 Jan-Feb;123(1):30-8
references: 18348477
references: IARC Monogr Eval Carcinog Risks Hum. 2004;83:1-1438
references: 15285078
references: IARC Monogr Eval Carcinog Risks Hum. 2007;89:1-592
references: 18335640
references: Regul Toxicol Pharmacol. 2008 Aug;51(3):306-10
references: 18508168
references: Nicotine Tob Res. 2006 Apr;8(2):309-13
references: 16766423
references: Cancer Epidemiol Biomarkers Prev. 2009 Jan;18(1):260-6
references: 19124507
references: Chem Res Toxicol. 1998 Jun;11(6):559-603
references: 9625726
references: Cancer Epidemiol Biomarkers Prev. 2010 Jun;19(6):1389-98
references: 20501750
references: Nicotine Tob Res. 2008 Dec;10(12):1773-82
references: 19023828
references: Cancer Detect Prev. 1996;20(2):114-21
references: 8706036