dry cleaning is not a 'dry' process. Clothes are soaked in a solvent other than water. Tetrachloroethylene (perchloroethylene), which the industry calls "perc," is the most widely used solvent. Alternative solvents are trichloroethane and petroleum spirits.[1] Dry cleaning can be controversial because it uses chlorocarbons, which are of concern for their potential toxicity and environmental impact.