Electronic cigarettes vaporize liquids to be inhaled and these liquids can contain nicotine. The e-cigarette is activated by pressing a button or by inhaling through it (see Fig. 1). In some cases, paper coverings are used to give the e-cigarette the look and feel of a real cigarette and even a burning tip can be simulated with LEDs. There has so far been little investigation into the health impact on e-cigarette smokers and no research at all has been done regarding their immediate environment. The question here is whether passive ‘vaping’ has an effect on others similar to passive smoking with cigarettes.
The aim of the investigations was to characterize the substances released into the air while an e-cigarette is being used. Tests were carried out involving a test subject in an 8 m³ stainless steel emission test chamber. The volunteer was asked to use an e-cigarette with three different liquids and to smoke a tobacco cigarette. The volatile organic compounds (VOCs) emitted and the (ultra-) fine particles were analyzed. Particular attention was paid to developments in the formaldehyde concentration in the chamber. It must be noted that the study does not claim to provide any kind of toxicological assessment.
In general, the emissions from the electronic cigarettes were lower than those of the normal tobacco cigarette. The release of substances into the air took place practically only via the smoker’s breath. Particularly in the case of the (ultra-) fine particles, it was possible to examine each individual draw on the cigarette. The smoke released similar to that from the burning end of a normal cigarette was negligible. There was no evidence of formaldehyde being released through the use of the e-cigarette. However, the use of the e-cigarette does have an influence on the indoor air quality in the room and therefore also the surroundings because the substances contained in the liquid are released. The fog fluid propylene glycol creates a visible vapour when the smoker exhales. The vaporized substances create an aerosol made up of (ultra-) fine particles in the e-cigarette which shrink again in the lung during the inhalation process. This slow evaporation of the condensed particles was not examined in the case of the tobacco cigarette, with which a high number of larger particles were found, due to their composition. In summary, e-cigarettes are a less significant source of indoor air pollution than typical tobacco cigarettes. They are, however, not completely free of emissions.