Chloroform is another name for the colorless, dense, liquid chemical compound trichloromethane. It is nonflammable and has a pleasant odor and a burning, sweet taste. Chloroform is about 40 times as sweet as sugar. Nearly insoluble (unable to be dissolved) in water, chloroform easily dissolves in alcohol, ether, acetone, gasoline, and other organic solvents. It can be prepared by the chlorination of ethyl alcohol or of methane. Once made from acetone and bleaching powder, chloroform is now prepared by the photochemical reaction of methane with chlorine.
Chloroform used for industrial purposes is usually made by the action of iron and acid on carbon tetrachloride. It is important as a solvent for gums, fats, resins, elements like sulfur and iodine, and many other organic compounds. Chloroform is also used to extract and purify penicillin.
Chloroform was popular as an anesthetic from the mid-1800s to around 1900, but it was found to cause death from paralysis of the heart in one patient in about 3,000. It also depresses most of the body's other organs, including the blood vessels, liver, pancreas, and kidneys. It is toxic to the liver. Oxygen-gas mixtures (oxygen with nitrous oxide, for example) regained use in anesthesia after 1900, and chloroform was replaced by safer compounds after about 1940. Years ago, chloroform was widely used in cough syrups, liniments, sedatives, and pain relievers. More recently, it has been listed as a carcinogen by the U.S. Environmental Protection Agency and been banned for use in drug, cosmetic, and food products since 1976.
The compound was discovered in 1831 by scientists in three different countries working at the same time: Samuel Guthrie (1782-1848) of the United States, Eugene Soubeiran (1797-1858) of France, and Justus von Liebig of Germany. (Guthrie, an American chemist and physician, also introduced Edward Jenner's vaccination technique to the United States.) M. J. Dumas of Paris described the composition of the new liquid and gave it the name "chloroform" in 1834 or 1835. The Frenchman Marie-Jean-Pierre Flourens (1794-1867) noted the anesthetic, but toxic, effect of chloroform on animals in March 1847.
Simpson Discovers Chloroform's Potency
Sir James Young Simpson, an eminent Scottish obstetrician, introduced the medical use of chloroform as an anesthetic in Edinburgh, Scotland, in November 1847. Earlier that year, Simpson had begun using ether to relieve the pain of childbirth, but was dissatisfied with some of ether's drawbacks, such as its disagreeable smell, the large quantities required, and the lung irritation it caused. Ether was also explosive, which was a problem for doctors who often worked by candlelight in rooms heated by fireplaces. A Liverpool chemist, David Waldie, suggested that Simpson try chloroform. On the evening of November 4,1847, Simpson and two doctor friends inhaled some chloroform and, after feeling very happy and talkative, promptly passed out. Impressed with chloroform's potency and rapid effects, Simpson immediately began using it in his obstetrical practice. The first baby bom to a mother who received chloroform for pain was named Anaesthesia.
Scottish clergymen quickly objected to this use of anesthesia, insisting the pain of childbirth was ordained by God. Simpson countered by citing the biblical account of the deep sleep cast on Adam when God took the first man's rib and used it to make Eve. The argument continued until 1853, when Queen Victoria (ruler of England from 1837-1901) chose to be chlo-roformed for the birth of her son Prince Leopold (1853-1884). This event quieted the clergy and made chloroform the most fashionable anesthetic—especially in England—for the next 50 years.
Although chloroform did carry some risk of heart failure, it was more pleasant to take and more powerful than ether. Queen Victoria's anesthetist, Dr. John Snow (1813-1858), developed an inhaler to regulate the amount of chloroform administered to a patient so that he or she felt no pain but remained conscious.
[See also Anesthesia ]