no passive smoking when using e-cig

When using tabacco cigarette there is always a problem with passive smoking. Is there the same problem when we use e-cigarette? Not really. There was a study which confirm the fact that the vapour from e-cig contains 75% of water, glycerine and very low level of nicotine. 30 people participted in this study: 10 people that smoke tabacco cigarette, and 20 pople smoking e-cigs (two groups: menthol and normal liquid). They were smoking/vaping in the average room size (40 m^3). It is confirmed that e-cig vapour is far far less dangerous than tabacco cigarette smoke. Full text of the study you can find here: http://www.mdpi.com/1660-4601/11/11/11177/htm.