acetaldehyde cigarettes in Mainstream Tobacco Smoke: Formation and Occurrence in Smoke and Bioavailability in the Smoker All E-Cigarettes Emit Harmful Chemicals,
Description
April 8, 2014

Of this massive number of compounds, 70 have confirmed carcinogenic activity in humans, and many more are suspected carcinogens
Further reading "Electronic nicotine delivery systems" (PDF)

The customers at our familys restaurant smoked