While there’s a great temptation to take a short cut, passive vaping can in no case be compared to passive smoking.
Cigarette smoking contains nearly 4,000 substances classified as toxic or carcinogenic which are not found in e-liquid vapour. What is more, the density of the smoke is much less than the vapour, the millions of droplets of which evaporate very rapidly in contact with air (approximately 15 seconds).
As for the “risk” of developing a dependence upon nicotine through passive vaping, the “risk” is practically nil. In actual fact, the vapour exhaled by vapers contains only a slight concentration of nicotine. The “olfactory effect”, if we may coin the term, may nonetheless be annoying, particularly if the vapour has been aromatised.