When I smoked weed heavily, I had persistent sinus inflammation/infection and coughed up black and grey mucus every day. Open wounds took forever to properly heal. Switching to vaporizing cleared those symptoms up pretty much immediately. Smoke is just plain bad for you, even smoked meat (BBQ) is linked to cancer!
Damn...I don't smoke pot, but I love smoked brisket lol. If smoking is a concern though couldn't people just bake more cookies? Doesn't that have the same effect (again - I've never used...but am supportive of legalization for the sake of ending the drug war and attacks on minorities and poor people).
