So I've been pondering this lately...how harmful is mold to a T? I have heard several times that the problem with mold is that the spores can enter the book lungs and either grow inside or seal the opening. My question is: Does anyone have reliable information to back this up? I could see if there was a ridiculous amount of mold in an enclosure that it could cause problems, but otherwise...mold occurs naturally and Ts have been alive for a looooong time, so it doesn't seem like it's as big a deal as it's said to be.