Tetrachloroethylene is a manufactured chemical used for dry cleaning and metal degreasing. It is also used in the manufacture of other chemicals and for textile finishing and dyeing. Tetrachloroethylene has been produced commercially since the early 1900s. At room temperature, tetrachloroethylene is a nonflammable colorless liquid. It evaporates easily and has a sharp, sweet odor similar to chloroform, which most people can smell at a level of about one part per million (ppm). Other names for tetrachloroethylene are perchloroethylene, PCE, tetrachloroethene, and "perc".

Results of animal studies using high levels of tetrachloroethylene indicated that it can cause liver and kidney damage. Exposure to very high levels of tetrachloroethylene was toxic to the unborn pups of pregnant rats and mice. The offspring of rats exposed to high levels of tetrachloroethylene during pregnancy exhibited changes in behavior. Since tetrachloroethylene has been shown to cause liver tumors in mice and kidney...