80 to 90% of what we inhale is PG or VG from the blend, the nic base and flavor base. There are long term studies on inhalation of both substances from factory workers with no harm involved. (a minor segment of the population has PG allergy which in most cases can be solved by
vaping only VG based contents).
Nicotine, while mildly addictive has no long term effects - yes it is a vasoconstrictor, but so are many substances and some vasodilators can be a danger to some medical conditions. In fact nicotine has many benefits - relaxed focus, enhanced memory, anti-Alzheimer's, anti-Parkinson's, anti-dementia, anti-inflammatory.
Some flavoring may be questionable but even then the substances are in trace amounts vs. cigarettes and even inner city air! The 'we don't know what the long term holds' is a specious argument and should be attacked in every instance it is used, whether by ANTZ or by those attempting to sound "reasonable" (or politically correct) within our community.
And we can absolutely say that vaping is healthier than smoking and it
may be healthier than
not vaping for certain individuals who have genes or have signs of the diseases listed above.