I was refering to smoke inhalation by being in a house fire, smoking cigs, smoking weed, ect. That would be direct inhalation. I guess large amounts of "popcorn smoke" (guess someone didn't pass Home EC, needless to say biology either) could potentially do the same thing if you smoked your popcorn. And i was also refering to long term (daily basis or all day) even common sense will tell you that is harmful to the lungs.