title: Smoke-free laws and secondhand smoke exposure in US non-smoking adults, 1999-2002.
abstract: OBJECTIVE
  To investigate the relationship between smoke-free law coverage and secondhand smoke (SHS) exposure in the United States non-smoking adult population.
  
  
  METHODS
  We used data from the 1999-2002 National Health and Nutrition Examination Survey, a cross-sectional survey designed to monitor the health and nutritional status of the US population. Serum cotinine levels were available for 5866 non-smoking adults from 57 survey locations. Each location was categorised into one of three groups indicating extensive, limited, and no coverage by a smoke-free law.
  
  
  METHODS
  The proportion of adults with SHS exposure, defined as having serum cotinine levels > or = 0.05 ng/ml.
  
  
  RESULTS
  Among non-smoking adults living in counties with extensive smoke-free law coverage, 12.5% were exposed to SHS, compared with 35.1% with limited coverage, and 45.9% with no law. Adjusting for confounders, men and women residing in counties with extensive coverage had 0.10 (95% confidence interval (CI) 0.06 to 0.16) and 0.19 (95% CI 0.11 to 0.34) times the odds of SHS exposure compared to those residing in counties without a smoke-free law.
  
  
  CONCLUSIONS
  These results support the scientific evidence suggesting that smoke-free laws are an effective strategy for reducing SHS exposure.
authors.affiliation: Centers for Disease Control and Prevention, National Center for Health Statistics, Hyattsville, Maryland 20782, USA.
authors.forename: Melanie S
authors.initials: MS
authors.lastname: Pickett
authors.forename: Susan E
authors.initials: SE
authors.lastname: Schober
authors.forename: Debra J
authors.initials: DJ
authors.lastname: Brody
authors.forename: Lester R
authors.initials: LR
authors.lastname: Curtin
authors.forename: Gary A
authors.initials: GA
authors.lastname: Giovino
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D003367:Cotinine / Q000097:blood; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000032:analysis* / Q000331:legislation & jurisprudence; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012147:Restaurants / Q000331:legislation & jurisprudence*; D012907:Smoking / Q000331:legislation & jurisprudence*; D014028:Tobacco Smoke Pollution / Q000032:analysis* / Q000331:legislation & jurisprudence; D014481:United States
chemical_list: D015415:Biomarkers; D014028:Tobacco Smoke Pollution; D003367:Cotinine