The good news is that most of the time, dry cleaning is enough to nix bad smells from your dry clean only garments. Sometimes however, dry cleaning doesn't combat the smells or can result in exchanging one smell for another.

The source of smelly dry cleaning can be traced to a chemical called perchloroethylene, otherwise referred to as “perc.” Perc is a laundering solvent that has been used in dry cleaning since the 1940s and is still the most commonly found chemical in traditional dry cleaning businesses.

Perchloroethylene or Tetrachloroethylene is a colorless, non-flammable liquid comprising 80-85% of the dry-cleaning fluids used in the United States. PCE has a sharp, sweet, ether-like odor which can be detected at concentrations as low as 1 ppm.