Martuzevicius D, et al. - The spatial and temporal patterns of exhaled e-cigarette aerosol at a bystander’s position were assessed. In addition, researchers compared it with conventional cigarette smoke emissions. Emissions from the tested electronic and conventional cigarettes were noted to be significantly different. Observations revealed differences in particle size between those exhaled following use of e-cigarettes and those emitted during smoking of conventional cigarettes. A rapid decrease in E-cigarette particle concentrations was noted following exhalation due to evaporation. They observed a much slower removal of particles following smoking conventional cigarettes and the removal was dependent upon the room ventilation rate.