Source:Marijuana In The Body - A Fact Sheet On The Effects Of Marijuana | Busted - America's War On Marijuana | FRONTLINE | PBSThe daily use of 1 to 3 marijuana joints appears to produce approximately the same lung damage and potential cancer risk as smoking 5 times as many cigarettes. (UCLA)
Benzopyrene will lodge itself into your DNA. It may not cause cancer, but just like cigarettes it can cause cancer and the risk is significantly higher. Marijuana isn't the healthy drug that people want to misrepresent it as. It may have a high tolerance in regards to toxicity, but it isn't healthy.