title: 'Herbal' but potentially hazardous: an analysis of the constituents and smoke emissions of tobacco-free waterpipe products and the air quality in the cafés where they are served.
abstract: BACKGROUND
  There are limited data on the composition and smoke emissions of 'herbal' shisha products and the air quality of establishments where they are smoked.
  
  
  METHODS
  Three studies of 'herbal' shisha were conducted: (1) samples of 'herbal' shisha products were chemically analysed; (2) 'herbal' and tobacco shisha were burned in a waterpipe smoking machine and main and sidestream smoke analysed by standard methods and (3) the air quality of six waterpipe cafés was assessed by measurement of CO, particulate and nicotine vapour content.
  
  
  RESULTS
  We found considerable variation in heavy metal content between the three products sampled, one being particularly high in lead, chromium, nickel and arsenic. A similar pattern emerged for polycyclic aromatic hydrocarbons. Smoke emission analyses indicated that toxic byproducts produced by the combustion of 'herbal' shisha were equivalent or greater than those produced by tobacco shisha. The results of our air quality assessment demonstrated that mean PM2.5 levels and CO content were significantly higher in waterpipe establishments compared to a casino where cigarette smoking was permitted. Nicotine vapour was detected in one of the waterpipe cafés.
  
  
  CONCLUSIONS
  'Herbal' shisha products tested contained toxic trace metals and PAHs levels equivalent to, or in excess of, that found in cigarettes. Their mainstream and sidestream smoke emissions contained carcinogens equivalent to, or in excess of, those of tobacco products. The content of the air in the waterpipe cafés tested was potentially hazardous. These data, in aggregate, suggest that smoking 'herbal' shisha may well be dangerous to health.
authors.affiliation: Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Canada.
authors.forename: Fadi
authors.initials: F
authors.lastname: Hammal
authors.affiliation: Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Canada.
authors.forename: Alyssa
authors.initials: A
authors.lastname: Chappell
authors.affiliation: School of Public Health, University of Alberta, Edmonton, Canada.
authors.forename: T Cameron
authors.initials: TC
authors.lastname: Wild
authors.affiliation: School of Public Health, University of Alberta, Edmonton, Canada.
authors.forename: Warren
authors.initials: W
authors.lastname: Kindzierski
authors.affiliation: Faculty of Engineering & Architecture, American University of Beirut, Beirut, Lebanon.
authors.forename: Alan
authors.initials: A
authors.lastname: Shihadeh
authors.affiliation: Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Canada.
authors.forename: Amanda
authors.initials: A
authors.lastname: Vanderhoek
authors.affiliation: Institute for Work and Health, Institut universitaire romand de Santé au Travail (IST), Lausanne, Switzerland.
authors.forename: Cong Khanh
authors.initials: CK
authors.lastname: Huynh
authors.affiliation: Institute for Work and Health, Institut universitaire romand de Santé au Travail (IST), Lausanne, Switzerland.
authors.forename: Gregory
authors.initials: G
authors.lastname: Plateel
authors.affiliation: Department of Anesthesiology and Pain Medicine, University of Alberta, Edmonton, Canada.
authors.forename: Barry A
authors.initials: BA
authors.lastname: Finegan
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis*; D006801:Humans; D028321:Plant Preparations / Q000032:analysis* / Q000737:chemistry; D012907:Smoking / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution / Q000032:analysis
chemical_list: D028321:Plant Preparations; D014028:Tobacco Smoke Pollution
keywords: Carcinogens; Non-Cigarette Tobacco Products; Secondhand Smoke