Dichloromethane is a member of the class of chloromethanes that is methane in which two of the hydrogens have been replaced by chlorine. A dense, non-flammible colourless liquid at room temperature (b.p. 40℃, d = 1.33) which is immiscible with water, it is widely used as a solvent, a paint stripper, and for the removal of caffeine from coffee and tea. It has a role as a polar aprotic solvent, a carcinogenic agent and a refrigerant. It is a member of chloromethanes and a volatile organic compound.

Methylene Chloride is a clear, colorless, nonflammable, volatile liquid chlorinated hydrocarbon with a sweet, pleasant smell and emits highly toxic fumes of phosgene when heated to decomposition. Methylene chloride is primarily used as a solvent in paint removers, but is also used in aerosol formulations, as a solvent in the manufacture of pharmaceuticals, as a degreasing agent, in electronics manufacturing and as an ethane foam blowing agent. Inhalation exposure to this substance irritates the nose and throat and affects the central nervous system. Methylene chloride is a possible mutagen and is reasonably anticipated to be a human carcinogen. (NCI05)