Linky
the conclusion of Professor John Britton’s 2014 review for PHE, that while vaping may not be 100% safe, most of the chemicals causing smoking-related disease are absent and the chemicals present pose limited danger, remains valid. The current best estimate is that e-cigarette use is around 95% less harmful to health than smoking
e-cigarettes release negligible levels of nicotine into ambient air with no identified health risks to bystanders
Quite encouraging, no?