High levels of humidity can create an atmosphere conducive to mildew, mold, etc. Unlike your bathroom which is usually painted with oil based paint, etc, your bedroom was not designed to handle super humid conditions. So, yes, it could cause mold or mildew. You can help prevent it with certain types of primer and paint and flooring (i.e. Carpet probably isn't the best option). However, if you live in a dry climate and aren't running it to the point of it being super humid in your bedroom, then you're probably okay.
at 6:18 AM on Jan. 31, 2010