title: Effects of user puff topography, device voltage, and liquid nicotine concentration on electronic cigarette nicotine yield: measurements and model predictions.
abstract: BACKGROUND
  Some electronic cigarette (ECIG) users attain tobacco cigarette-like plasma nicotine concentrations while others do not. Understanding the factors that influence ECIG aerosol nicotine delivery is relevant to regulation, including product labeling and abuse liability. These factors may include user puff topography, ECIG liquid composition, and ECIG design features. This study addresses how these factors can influence ECIG nicotine yield.
  
  
  METHODS
  Aerosols were machine generated with 1 type of ECIG cartridge (V4L CoolCart) using 5 distinct puff profiles representing a tobacco cigarette smoker (2-s puff duration, 33-ml/s puff velocity), a slow average ECIG user (4 s, 17 ml/s), a fast average user (4 s, 33 ml/s), a slow extreme user (8 s, 17 ml/s), and a fast extreme user (8 s, 33 ml/s). Output voltage (3.3-5.2 V or 3.0-7.5 W) and e-liquid nicotine concentration (18-36 mg/ml labeled concentration) were varied. A theoretical model was also developed to simulate the ECIG aerosol production process and to provide insight into the empirical observations.
  
  
  RESULTS
  Nicotine yields from 15 puffs varied by more than 50-fold across conditions. Experienced ECIG user profiles (longer puffs) resulted in higher nicotine yields relative to the tobacco smoker (shorter puffs). Puff velocity had no effect on nicotine yield. Higher nicotine concentration and higher voltages resulted in higher nicotine yields. These results were predicted well by the theoretical model (R (2) = 0.99).
  
  
  CONCLUSIONS
  Depending on puff conditions and product features, 15 puffs from an ECIG can provide far less or far more nicotine than a single tobacco cigarette. ECIG emissions can be predicted using physical principles, with knowledge of puff topography and a few ECIG device design parameters.
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon; Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA.
authors.forename: Soha
authors.initials: S
authors.lastname: Talih
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon; Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA.
authors.forename: Zainab
authors.initials: Z
authors.lastname: Balhas
authors.affiliation: Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Eissenberg
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon;
authors.forename: Rola
authors.initials: R
authors.lastname: Salman
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon;
authors.forename: Nareg
authors.initials: N
authors.lastname: Karaoghlanian
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon; Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA.
authors.forename: Ahmad
authors.initials: A
authors.lastname: El Hellani
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon; Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA.
authors.forename: Rima
authors.initials: R
authors.lastname: Baalbaki
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon; Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA.
authors.forename: Najat
authors.initials: N
authors.lastname: Saliba
authors.affiliation: Department of Mechanical Engineering, American University of Beirut, Beirut, Lebanon; Department of Psychology, Center for the Study of Tobacco Products, Virginia Commonwealth University, Richmond, VA as20@aub.edu.lb.
authors.forename: Alan
authors.initials: A
authors.lastname: Shihadeh
mesh_terms: D001519:Behavior; D066300:Electronic Nicotine Delivery Systems / Q000295:instrumentation / Q000523:psychology; D004867:Equipment Design; D006801:Humans; D008954:Models, Biological; D009538:Nicotine / Q000008:administration & dosage*; D011356:Product Labeling; D012907:Smoking / Q000523:psychology
chemical_list: D009538:Nicotine