AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
E-cigarettes: Aerosol Sampling and Droplet Size Measurement
JOHN MCAUGHEY, Ross Cabot, Caner Yurteri, David Lawson, British American Tobacco
Abstract Number: 585 Working Group: Linking Aerosols with Public Health in a Changing World
Abstract Electronic Cigarettes (also known as e-cigarettes or Electronic Nicotine Delivery Systems – ENDS), are a new type of product gaining popularity with adult cigarette smokers. They typically produce a condensation aerosol by rapidly evaporating a formulation containing nicotine, water, glycerol and propylene glycol mixtures.
The regulatory landscape around these devices is diverse and they are variously considered as consumer, tobacco or medicine products. Areas of regulatory interest may include the nature and consistency of the device output and how these may influence delivered and retained dose of the formulation components. Thus there is a core need for particle size and concentration data, and the development of robust measurement methods.
This study sought to measure droplet size distributions by real-time analytical methods using commercially available equipment. Measurements were conducted by electrical mobility (EM: Model DMS-500 MkII, Cambustion, UK) and by laser diffraction (LD: Spraytec, Malvern, UK). The Smoking Cycle Simulator (SCS: Cambustion, UK) was used to generate appropriate puff profiles with minimal dilution.
Volume-weighted median droplet diameters (dV50) from a variety of e-cigarette devices were typically less than 500 nm by LD and less than 300 nm for EM, slightly larger than equivalent tobacco smoke measurements of approximately 210 nm. Precision data were dependent on the e-cigarette tested but coefficients of variation of less than 4–5% were observed for the better performing products. This degree of precision meets the acceptance criteria for droplet size distribution (dV50 ± 20% for dV50 < 1000 nm) for laser diffraction measurements defined in the US Pharmacopeia. No equivalent standards are available for electrical mobility measurements. In conclusion, droplet size measurement for e-cigarettes can be readily achieved using commercially available sampling and measurement instrumentation, with suitable precision to meet potential regulatory requirements.