Ethyl chloride, also known as chloroethane and monochloroethane, is a chemical compound once used as a refrigerant, a foam-blowing agent, an anti-knock additive for leaded gasoline, and an anesthetic. It is classified as a halogenated hydrocarbon, meaning it contains carbon and hydrogen atoms with one or more of the latter being replaced by halogen agents; in this case, chlorides. Ethyl chloride is produced as either a colorless gas or liquid in a reaction series using aluminum chloride as a catalyst. It is also a byproduct of polyvinyl chloride manufacturing.
Industrial use of this chlorinated hydrocarbon has declined sharply due to environmental concerns. In fact, the only consistent use of this chemical in manufacturing today is in the production of cosmetics and paints, where it is used to enhance the binding and thickening properties of cellulose. Ethyl chloride has retained value as a skin coolant and anesthetic, however, and has emerged as a treatment for pain relief from muscle soreness.
Put simply, this compound is a topical vapocoolant, or skin refrigerant. Since it produces an instant numbing effect, it is sometimes used to provide on-the-spot treatment for sports-related injuries. It is also used before and after minor surgical procedures, or to numb the skin prior to receiving an injection or intravenous medication. The chemical is also used to lessen myofascial pain and to improve limited motion of the limbs.
While anesthetic ethyl chloride spray does indeed relieve pain due to muscle tension or surgical incision, there are risks associated with its use. For one thing, ethyl chloride is not intended for long-term use since it is a known liver and kidney carcinogen. In fact, use of this agent, even as a topical spray, is restricted in the U.S. state of California for this reason. It is also necessary to protect the area surrounding the treatment site with petroleum jelly to prevent the skin from freezing. For that matter, if this product is targeted to an area for more than a few seconds, the skin may become damaged and permanently lose pigment.
Serious side effects are rare, although certain individuals may experience an allergic reaction indicated by a local rash, difficulty breathing, or swelling at the application site or of the tongue. Due to the “fast freeze” effects of ethyl chloride, contact with the mucous membranes of the eyes, mouth or nose should be avoided. Use of this product should also be avoided during pregnancy unless truly needed. It should also be noted that it is not known if this chemical passes through breast milk.