Simple answer: nope
So far, any test that you might read about that says yes, are all falsified propaganda.
Every unbiased tests done so far have yet to show a single bad thing.
Every ex-smoker have had nothing but better health due to
vaping.
There's no 100% certainty yet, but we are looking at 95% and higher of "better than cigarettes" which that 5% being nothing more than a "possible" margin that they are giving as a "in case', but so far, it's been more like 99.9% better.
You get more harmful stuff into your lungs from walking down a street with a few cars driving by.
The only negative so far is if you're sensitive to PG, or if you do things wrong such as burning your
coils and wick, or have too high nicotine levels in your liquid.