title: Exposure to secondhand smoke outside of a bar and a restaurant and tobacco exposure biomarkers in nonsmokers.
abstract: BACKGROUND
  With an increase in indoor smoking bans, many smokers smoke outside establishments and near their entrances, which has become a public health concern.
  
  
  OBJECTIVE
  We characterized the exposure of nonsmokers to secondhand smoke (SHS) outside a restaurant and bar in Athens, Georgia, where indoor smoking is banned, using salivary cotinine and urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL).
  
  
  METHODS
  In a crossover study, we assigned 28 participants to outdoor patios of a restaurant and a bar and an open-air site with no smokers on three weekend days; participants visited each site once and stayed for 3 hr. We collected saliva and urine samples immediately before and after the visits (postexposure) and on the following morning and analyzed samples for cotinine and total NNAL, respectively. Regression models were fitted and changes in biomarkers were contrasted between locations.
  
  
  RESULTS
  Postexposure and preexposure geometric mean salivary cotinine concentrations differed by 0.115 ng/mL [95% confidence interval (CI): 0.105, 0.126)] and by 0.030 ng/mL (95% CI: 0.028, 0.031) for bar and restaurant visits, respectively. There were no significant post- and preexposure differences in cotinine levels after control site visits, and changes after bar and restaurant site visits were significantly different from changes after control site visits (p < 0.001). Results comparing next-day and preexposure salivary cotinine levels were similar. Next-day creatinine-corrected urinary NNAL concentrations also were higher than preexposure levels following bar and restaurant visits [1.858 pg/mg creatinine higher (95% CI: 0.897, 3.758) and 0.615 pg/mg creatinine higher (95% CI: 0.210, 1.761), respectively], and were significantly different from changes after the control visits (p = 0.005).
  
  
  CONCLUSIONS
  Salivary cotinine and urinary NNAL increased significantly in nonsmokers after outdoor SHS exposure. Our findings indicate that such exposures may increase risks of health effects associated with tobacco carcinogens.
authors.affiliation: Department of Environmental Health Science, College of Public Health, University of Georgia, Athens, Georgia 30602-2102, USA.
authors.forename: Gideon
authors.initials: G
authors.lastname: St Helen
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Bernert
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Hall
authors.forename: Connie S
authors.initials: CS
authors.lastname: Sosnoff
authors.forename: Yang
authors.initials: Y
authors.lastname: Xia
authors.forename: John R
authors.initials: JR
authors.lastname: Balmes
authors.forename: John E
authors.initials: JE
authors.lastname: Vena
authors.forename: Jia-Sheng
authors.initials: JS
authors.lastname: Wang
authors.forename: Nina T
authors.initials: NT
authors.lastname: Holland
authors.forename: Luke P
authors.initials: LP
authors.lastname: Naeher
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D018592:Cross-Over Studies; D004784:Environmental Monitoring; D005845:Georgia; D006801:Humans; D009538:Nicotine / Q000032:analysis; D009602:Nitrosamines / Q000032:analysis; D011725:Pyridines / Q000032:analysis; D012147:Restaurants; D012463:Saliva / Q000737:chemistry / Q000187:drug effects; D012907:Smoking / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D015415:Biomarkers; D009602:Nitrosamines; D011725:Pyridines; D014028:Tobacco Smoke Pollution; D009538:Nicotine; C099565:4-(methylnitrosamino)-1-(3-pyridyl)-1-butan-1-ol