“There is a consensus that e-cigarettes are safer than tobacco cigarettes, since e-cigarettes contain no tobacco and thus no tar, with some estimating them to be around 95% safer, although the longer-term effects of e-cigarettes have not been established,” quotes The Health Survey for England (HSE) as it details current trends in smoking.
https://www.planetofthevapes.co.uk/news/health-studies/2019-12-13_health-survey-for-england.html