I see they didnt compare it to something comparable in effect like alcohol. You know why? Because no one has ever been prooven to die from the effects of smoking cannabis. Cannabis is far worse than tobacco as it contains many more times the amount or tar,you know the stuff that clogs your heart and archeries. But alcohol now that drug has alot to answer for,its scientificly prooven that alcohol can kill you. The craziest thing is whilst cannabis remains illegal people are forced to smoke whatever there dealers provide,and i can guarantee that the majority of that stuff is more harmfull to your health due to the amount of chemicals,glass or whatever else adds weight. Simple fact legal cannabis is safer cannabis.