Perchloroethylene, the chemical most widely used in dry cleaning, has been shown to cause cancer in animals. You breathe low levels of it where dry-cleaned goods are stored and as you wear dry-cleaned clothing. Try to minimize your exposure. If possible, seek out a “green” dry cleaner or buy clothes that don’t require dry cleaning. Psst: Sometimes you can get away with hand-washing or cold-water-washing dry-clean-only clothes. At least, we have.