Trichloroethylene, a colourless, toxic, volatile liquid belonging to the family of organic halogencompounds, nonflammable under ordinary conditions and used as a solvent and in adhesives. Trichloroethylene has a subtle, sweet odour. Trichloroethylene is used in dry cleaning, in degreasing of metal objects, and in extraction processes, such as removal of caffeine from coffee or of fats and waxes from cotton and wool.