Effect of Volatilization of E-liquid on Electronic Cigarette Aerosol Composition

NATHAN EDDINGSAAS, Chamodhi Ravihansi Polgampola Ralalage, Edward Hensel, Risa Robinson, Rochester Institute of Technology

     Abstract Number: 563
     Working Group: Health-Related Aerosols

Abstract
Electronic cigarettes generate aerosol by vaporizing the e-liquid (mainly propylene glycol (PG), glycerol (GL), and nicotine (Nic)). Deposition location and efficiency within the respiratory tract will differ if a compound is in the gas phase or particle phase. This work determined the composition of the aerosol a user is exposed to and how it varies from the e-liquid and what causes the change in composition. Experiments were designed to study multiple possible mechanisms using a lab synthesized e-liquid with a known composition. E-liquid and its resultant aerosol were analyzed for designed experiments by gas chromatography-flame ionization detector (GC-FID). Results from these experiments suggest that the change in composition results from the condensation phase of aerosol formation with more volatile components such as propylene glycol, present at a reduced fraction in the aerosol only in experiments where the condensation step was isolated. In addition, the inclusion of organic acid into the e-liquid (termed salted e-liquid by manufacturers) influences nicotine concentration in the resulting aerosol. The change in composition of aerosol vs e-liquid across several commercial products varying in amount and type of added acid were also evaluated.