title: Disposable electronic cigarettes and electronic hookahs: evaluation of performance.
abstract: BACKGROUND
  The purpose of this study was to characterize the performance of disposable button-activated and disposable airflow-activated electronic cigarettes (EC) and electronic hookahs (EH).
  
  
  METHODS
  The airflow rate required to produce aerosol, pressure drop, and the aerosol absorbance at 420 nm were measured during smoke-outs of 9 disposable products. Three units of each product were tested in these experiments.
  
  
  RESULTS
  The airflow rates required to produce aerosol and the aerosol absorbances were lower for button-activated models (3 mL/s; 0.41-0.55 absorbance) than for airflow-activated models (7-17 mL/s; 0.48-0.84 absorbance). Pressure drop was also lower across button-activated products (range = 6-12 mm H2O) than airflow-activated products (range = 15-67 mm H20). For 25 of 27 units tested, airflow did not have to be increased during smoke-out to maintain aerosol production, unlike earlier generation models. Two brands had uniform performance characteristics for all parameters, while 3 had at least 1 product that did not function normally. While button-activated models lasted 200 puffs or less and EH airflow-activated models often lasted 400 puffs, none of the models produced as many puffs as advertised. Puff number was limited by battery life, which was shorter in button-activated models.
  
  
  CONCLUSIONS
  The performance of disposable products was differentiated mainly by the way the aerosol was produced (button vs airflow-activated) rather than by product type (EC vs EH). Users needed to take harder drags on airflow-activated models. Performance varied within models, and battery life limited the number of puffs. Data suggest quality control in manufacturing varies among brands.
authors.affiliation: Environmental Toxicology Program, University of California, Riverside, CA; Department of Cell Biology and Neuroscience, University of California, Riverside, CA.
authors.forename: Monique
authors.initials: M
authors.lastname: Williams
authors.affiliation: Department of Cell Biology and Neuroscience, University of California, Riverside, CA.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Ghai
authors.affiliation: Department of Cell Biology and Neuroscience, University of California, Riverside, CA talbot@ucr.edu.
authors.forename: Prue
authors.initials: P
authors.lastname: Talbot
mesh_terms: D000336:Aerosols; D066300:Electronic Nicotine Delivery Systems / Q000295:instrumentation*; D004867:Equipment Design; D006801:Humans; D009330:Nebulizers and Vaporizers; D009538:Nicotine / Q000008:administration & dosage*
chemical_list: D000336:Aerosols; D009538:Nicotine
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