Theres SOME evidence, none clear, alcohol can have a bad effect and cause mental problems, someone heavily depressed who drinks alcohol will often be worse.
Long term alcoholics are rarely anything but very depressed and unhappy people.
Anyway he was both right and wrong, cannibis itself ISN'T harmful, we all take dozens of substances that change our brain chemistry every day, for better or worse, caffeine, alcohol, htp triptophan from chicken, etc, etc.
Why he's wrong is, cannibis itself isn't harmful but while its illegal the distribution of it can well be harmful, gangs growing and selling the stuff, fighting over supply. We've created more crime and harm from making it illegal and forcing the distribution and sale to be so highly profitable for criminals, than any harm cannabis would cause a few people if it were legal.
Theres VERY minor evidence it can cause some pretty severe mental issues, but not much has been found to say if those same people weren't predisposed to the problem in the first place, were already developing it, or if something else potentially caused it.
Remember if you go into a cancer ward and ask how many of them have eaten a Lion Bar before, if 90% said yes you could incorrectly conclude that Lion Bars cause cancer. Extremely limited research in the area(in an area) can come out with some wild and completely unsubstantiated theories. Due to the illegal nature of cannabis there hasn't been much widespread and consistant research done.
If it was in a house yes but its rare for a normally very cold garage to be showing the same kind of heat.
Normal heat readings from a house wouldn't be normal for a garage or a shed.
