A home can have all sorts of lingering and unpleasant smells, such as a stench from the bathroom. And, while some household smells are merely objectionable, others can be an indication of a hazardous condition. Household odors that may be cause for concern include a natural gas smell which is similar to a rotten egg, a fishy smell that could be emanating from a wall outlet, a musty or dusty smell which could be the result of mold or mildew, and a sewage odor which could be a sign of a clogged drain pipe. Learn about potentially hazardous household odors and how to successfully remediate each.