Does smoke from marijuana vaporizers contain carcinogens?

YES: Numerous studies have shown that marijuana smoke contains carcinogens, and irritates the lungs. Marijuana smoke contains 50-70% more carcinogenic hydrocarbons than tobacco smoke. Marijuana users usually inhale more deeply and hold their breath longer than tobacco smokers do -- increasing lungs' exposure to carcinogenic smoke. Also there's dysregulation in pot smokers' lung epithelial cells.

Yes but not problem: Yes but does not cause increase in cancer, even smoked heavily in joints chronically.