Lahart I, Darcy P, Gidlow C, Calogiuri G (2019) The effects of green exercise on physical and mental wellbeing: a systematic review
E-cigarettes: Percentage of adults aged 18 years and older who used e-cigarettes at least once in their lifetime and, at the time of the interview, used e-cigarettes every day or some days
doi:10.1016/j.celrep.2018.03.030 pmid:29617674 Tolu S, Eddine R, Marti F, David V, Graupner M, Pons S, Baudonnat M, Husson M, Besson M, Reperant C, Zemdegs J, Pags C, Hay YA, Lambolez B, Caboche J, Gutkin B, Gardier AM, Changeux JP, Faure P, Maskos U (2013) Co-activation of VTA DA and GABA neurons mediates nicotine reinforcement
This makes them great for gifts and collecting
Manufacturers say their products are aimed at smokers who want the "taste of tobacco with no smoke and less smell"