http://www.nbcnews.com/health/cancer/you-vape-high-levels-formaldehyde-hidden-e-cigs-n290826
There seems to be a concerted effort to make e-cigs look as unhealthy as possible. But when you dig into the info, you find things like this, in this NBC article
“”We are not saying e-cigarettes are more hazardous than cigarettes,” he said. “We are only looking at one chemical. … The jury is really out on how safe these drugs are.” There are more than 8,000 chemicals in tobacco smoke, so it’s hard to pinpoint whether formaldehyde is the main culprit in cigarette-related cancers”
So while 1 chemical of 8,000 may be present in higher quantities, some 7,000 of the others probably are not. Given the base of e-cig liquids and the vast chemical difference between those and regular tobacco, it’s likely very few components are carcinogenic and are present in such low quantities to have no measurable effect.
Regular cigarette smokers receive about 3 times the allowed dose of people who work in radioactive environments annually (check out this enlightening video https://www.youtube.com/watch?v=TRL7o2kPqw0) Regular smoking dumps radioactive lead and polonium into the smokers lungs, along with about 4,000 other carcinogens (guessing, since roughly half of all possible chemical compounds are carcinogenic)
Also carcinogenicity is based on the LTM (linear threshold model) which most epidemiologists now suspect is not accurate, it’s basically if you pump a lab rat so full of a carcinogen that a tiny bit more will kill it outright, then divide the dose by how many rats got cancer, you project how many cancers smaller doses will cause. However our bodies have numerous mechanisms which combat the formation of cancers, and alot of the data available now suggests the LTM is wrong, and that at low doses there is no measurable increase in cancers (depending on the compound)
All in all, I doubt e-cigs will prove to be any more carcinogenic than a moderate beer or wine drinking habit
Also, nicotine has health benefits, there is strong evidence that it delays or even prevents many neuro-degenerative disorders like Parkinson’s and Alzheimer’s. With e-cigs you get the benefits of nicotine without the drawbacks of massive doses of carcinogens.