title: Did smokefree legislation in England reduce exposure to secondhand smoke among nonsmoking adults? Cotinine analysis from the Health Survey for England.
abstract: BACKGROUND
  On 1 July 2007, smokefree legislation was implemented in England, which made virtually all enclosed public places and workplaces smokefree.
  
  
  OBJECTIVE
  We examined trends in and predictors of secondhand smoke exposure among nonsmoking adults to determine whether exposure changed after the introduction of smokefree legislation and whether these changes varied by socioeconomic status (SES) and by household smoking status.
  
  
  METHODS
  We analyzed salivary cotinine data from the Health Survey for England that were collected in 7 of 11 annual surveys undertaken between 1998 and 2008. We conducted multivariate regression analyses to examine secondhand smoke exposure as measured by the proportion of nonsmokers with undetectable levels of cotinine and by geometric mean cotinine.
  
  
  RESULTS
  Secondhand smoke exposure was higher among those exposed at home and among lower-SES groups. Exposure declined markedly from 1998 to 2008 (the proportion of participants with undetectable cotinine was 2.9 times higher in the last 6 months of 2008 compared with the first 6 months of 1998 and geometric mean cotinine declined by 80%). We observed a significant fall in exposure after legislation was introduced--the odds of having undetectable cotinine were 1.5 times higher [95% confidence interval (CI): 1.3, 1.8] and geometric mean cotinine fell by 27% (95% CI: 17%, 36%) after adjusting for the prelegislative trend and potential confounders. Significant reductions were not, however, seen in those living in lower-social class households or homes where smoking occurs inside on most days.
  
  
  CONCLUSIONS
  We found that the impact of England's smokefree legislation on secondhand smoke exposure was above and beyond the underlying long-term decline in secondhand smoke exposure and demonstrates the positive effect of the legislation. Nevertheless, some population subgroups appear not to have benefitted significantly from the legislation. This finding suggests that these groups should receive more support to reduce their exposure.
authors.affiliation: Department for Health, and the UK Centre for Tobacco Control Studies, University of Bath, Claverton Down, Bath, United Kingdom. m.sims@bath.ac.uk
authors.forename: Michelle
authors.initials: M
authors.lastname: Sims
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Mindell
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Jarvis
authors.forename: Colin
authors.initials: C
authors.lastname: Feyerabend
authors.forename: Heather
authors.initials: H
authors.lastname: Wardle
authors.forename: Anna
authors.initials: A
authors.lastname: Gilmore
mesh_terms: D000293:Adolescent; D000328:Adult; D016902:Air Pollution, Indoor / Q000032:analysis / Q000331:legislation & jurisprudence* / Q000517:prevention & control; D002849:Chromatography, Gas; D002853:Chromatography, Liquid; D016001:Confidence Intervals; D003367:Cotinine / Q000032:analysis*; D003430:Cross-Sectional Studies; D004739:England / Q000453:epidemiology; D004781:Environmental Exposure / Q000032:analysis / Q000331:legislation & jurisprudence* / Q000517:prevention & control; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D012189:Retrospective Studies; D012463:Saliva / Q000737:chemistry*; D012907:Smoking / Q000453:epidemiology / Q000331:legislation & jurisprudence; D000074606:Smoking Prevention; D012959:Socioeconomic Factors; D053719:Tandem Mass Spectrometry; D014028:Tobacco Smoke Pollution / Q000032:analysis / Q000331:legislation & jurisprudence* / Q000517:prevention & control; D055815:Young Adult
chemical_list: D014028:Tobacco Smoke Pollution; D003367:Cotinine