ok this was getting no replies in the medical section so im gonna try here ok i was just on the forums in the seasoned tokers section when i ran across a thread asking if anyone else smoked a certain way. the thread turned into a discussion about your lungs getting hurt from "ghosting" a hit or holding it in longer than a certain amount of time. so i was wondering... how long is too long to hold in your hit?? any proven medical information is much obliged.