title: Nicotine and carcinogen exposure with smoking of progressively reduced nicotine content cigarette.
abstract: BACKGROUND
  Reducing the nicotine content of cigarettes to make them non-addictive has been widely discussed as a potential strategy for tobacco regulation. A major concern with nicotine reduction is that smokers will compensate for reduced nicotine by smoking more cigarettes and/or smoking more intensively, thereby increasing their exposure to tobacco smoke toxins. This study examined whether gradual reduction in nicotine exposure increases exposure to tobacco smoke toxins.
  
  
  METHODS
  This 10-week longitudinal study of 20 healthy smokers involved smoking their usual brand followed by different types of research cigarettes with progressively lower nicotine content, each smoked for 1 week. Subjects were followed for 4 weeks after returning to smoking their usual brand (or quitting). Smoking behaviors, chemical biomarkers of tobacco smoke exposure, and cardiovascular effect biomarkers were measured.
  
  
  RESULTS
  Intake of nicotine declined progressively as the nicotine content of cigarettes was reduced, with little evidence of compensation. Cigarette consumption and markers of exposure to carbon monoxide and polycyclic aromatic hydrocarbons, as well as cardiovascular biomarkers remained stable, whereas urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol excretion decreased. Twenty-five percent of participants had spontaneously quit smoking 4 weeks after completing the research cigarette taper.
  
  
  CONCLUSIONS
  Our findings with reduced nicotine content cigarettes differ from those of commercial low yields for which compensatory smoking for lower nicotine delivery is substantial. Our data suggest that the degree of nicotine dependence of smokers can be lowered without increasing their exposure to tobacco smoke toxins. Gradual reduction of nicotine content of cigarettes seems to be feasible and should be further evaluated as a national tobacco regulatory strategy.
authors.affiliation: Division of Clinical Pharmacology and Experimental Therapeutics, Medical Service, San Francisco General Hospital Medical Center, Department of Medicine, University of California, San Francisco, CA 94143-1220, USA. NBenowitz@MedSFGH.ucsf.edu
authors.forename: Neal L
authors.initials: NL
authors.lastname: Benowitz
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Hall
authors.forename: Susan
authors.initials: S
authors.lastname: Stewart
authors.forename: Margaret
authors.initials: M
authors.lastname: Wilson
authors.forename: Delia
authors.initials: D
authors.lastname: Dempsey
authors.forename: Peyton
authors.initials: P
authors.lastname: Jacob
mesh_terms: D000293:Adolescent; D000328:Adult; D016739:Behavior, Addictive; D002273:Carcinogens / Q000008:administration & dosage* / Q000378:metabolism; D002319:Cardiovascular System; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009538:Nicotine / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism / Q000652:urine; D012907:Smoking / Q000097:blood / Q000378:metabolism*; D016540:Smoking Cessation; D014026:Nicotiana
chemical_list: D002273:Carcinogens; D009538:Nicotine