title: Carboxyhaemoglobin levels in water-pipe and cigarette smokers.
abstract: Water-pipe smoking is growing in popularity, especially among young people, because of the social nature of the smoking session and the assumption that the effects are less harmful than those of cigarette smoking. It has however been shown that a single water-pipe smoking session produces a 24-hour urinary cotinine level equivalent to smoking 10 cigarettes per day.
  
  
  OBJECTIVE
  We aimed to measure carboxyhaemoglogin (COHb) blood levels before and after water-pipe and cigarette smoking sessions.
  
  
  METHODS
  Self-confessed smokers older than 18 years (N=30) volunteered to smoke a water-pipe or a cigarette and have their blood COHb levels measured under controlled conditions.
  
  
  RESULTS
  Mean baseline COHb levels were 2.9% for the 15 cigarette smokers and 1.0% for the 15 water-pipe smokers. Levels increased by a mean of 481.7% in water-pipe smokers as opposed to 39.9% in cigarette smokers.
  
  
  CONCLUSIONS
  The study demonstrated that water-pipe smokers had significantly higher increases in blood COHb levels than cigarette smokers during a single smoking session.
authors.affiliation: Lung Unit, Department of Internal Medicine, Steve Biko Academic Hospital, School of Medicine, University of Pretoria. theronansa@gmail.com
authors.forename: Ansa
authors.initials: A
authors.lastname: Theron
authors.forename: Cedric
authors.initials: C
authors.lastname: Schultz
authors.forename: James A
authors.initials: JA
authors.lastname: Ker
authors.forename: Nadia
authors.initials: N
authors.lastname: Falzone
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D002245:Carbon Dioxide / Q000378:metabolism; D002263:Carboxyhemoglobin / Q000378:metabolism*; D015331:Cohort Studies; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D009330:Nebulizers and Vaporizers; D012907:Smoking / Q000097:blood*; D013019:South Africa; D014026:Nicotiana / Q000378:metabolism*; D014867:Water; D055815:Young Adult
chemical_list: D014867:Water; D002245:Carbon Dioxide; D002263:Carboxyhemoglobin