title: Racial differences in the relationship between number of cigarettes smoked and nicotine and carcinogen exposure.
abstract: BACKGROUND
  Black smokers are reported to have higher lung cancer rates and greater tobacco dependence at lower levels of cigarette consumption compared to non-Hispanic White smokers. We studied the relationship between cigarettes per day (CPD) and biomarkers of nicotine and carcinogen exposure in Black and White smokers.
  
  
  METHODS
  In 128 Black and White smokers, we measured plasma nicotine and its main proximate metabolite cotinine, urine nicotine equivalents, 4-(methylnitrosamino)-1-(3)pyridyl-1-butanol (NNAL), and polycyclic aromatic hydrocarbon (PAH) metabolites.
  
  
  RESULTS
  The dose-response between CPD and nicotine equivalents, and NNAL and PAH was flat for Black but positive for White smokers (Race × CPD interaction, all ps < .05). Regression estimates for the Race × CPD interactions were 0.042 (95% CI 0.013-0.070), 0.054 (0.023-0.086), and 0.028 (0.004-0.052) for urine nicotine equivalents, NNAL, and PAHs, respectively. In contrast there was a strong correlation between nicotine equivalents and NNAL and PAH independent of race. Nicotine and carcinogen exposure per individual cigarette was inversely related to CPD. This inverse correlation was stronger in Black compared to White smokers and stronger in menthol compared to regular cigarette smokers (not mutually adjusted).
  
  
  CONCLUSIONS
  Our data indicate that Blacks on average smoke cigarettes differently than White smokers such that CPD predicts smoke intake more poorly in Black than in White smokers.
authors.affiliation: Department of Medicine, University of California, San Francisco, San Francisco, CA 94143-1220, USA. nbenowitz@medsfgh.ucsf.edu
authors.forename: Neal L
authors.initials: NL
authors.lastname: Benowitz
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Dains
authors.forename: Delia
authors.initials: D
authors.lastname: Dempsey
authors.forename: Margaret
authors.initials: M
authors.lastname: Wilson
authors.forename: Peyton
authors.initials: P
authors.lastname: Jacob
mesh_terms: D000293:Adolescent; D000328:Adult; D001741:Black or African American / Q000523:psychology; D000368:Aged; D002273:Carcinogens / Q000032:analysis; D003367:Cotinine / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009538:Nicotine / Q000097:blood* / Q000652:urine; D009602:Nitrosamines / Q000652:urine; D011084:Polycyclic Aromatic Hydrocarbons / Q000652:urine; D011725:Pyridines / Q000652:urine; D012495:San Francisco; D012907:Smoking / Q000097:blood / Q000208:ethnology* / Q000523:psychology / Q000652:urine; D014029:Tobacco Use Disorder / Q000097:blood / Q000208:ethnology* / Q000523:psychology / Q000652:urine; D044465:White People / Q000523:psychology; D055815:Young Adult
chemical_list: D002273:Carcinogens; D009602:Nitrosamines; D011084:Polycyclic Aromatic Hydrocarbons; D011725:Pyridines; D009538:Nicotine; C099565:4-(methylnitrosamino)-1-(3-pyridyl)-1-butan-1-ol; D003367:Cotinine