Lithium is an alkali metal. It is silvery white in color. When burned, it gives off a crimson glow. Lithium occurs in nature only in compound form. The story of lithium's discovery began in 1800 with a report by a Brazilian scientist named Jose Bonifacio de Andrada e Silvio. He discovered two metals while traveling in Sweden and called them "spodumene" and "petalite." These two metals were rediscovered by a Swedish chemist, E. T. Svenenstjema. Investigation of the metals was puzzling, because anywhere from one to ten percent of the components was unaccounted for during chemical analysis.
Arfvedson's Studies Lead to Discovery
The explanation for this problem was provided by Johan August Arfvedson, a young man working in the laboratory of Jons Berzelius. The components Arfvedson identified in the mineral added up to 95 or 105 percent, but never 100 percent. He concluded that these results could be explained only by the presence of a new element in the mineral. He proposed the name "lithium" for the new element, which comes from the Greek word "lithos," or "stone."
Arfvedson was never able to isolate the pure metal itself. That was accomplished by W. T. Brande (1788-1866) and Humphry Davy (1778-1829) working independently in 1818. The men obtained the metal through electrolysis of lithium oxide. By 1855, Bunsen and Matthiessen had discovered a way to produce the metal in large quantities and could manufacture a few grams of it in a matter of minutes.
Researchers soon found lithium in both plants and animals, although only in small amounts. In 1860, Gustav Kirchhoff and Bunsen found lithium in the ash of grapes, tobacco, kelp, and in milk. Later, researchers also found the element in human urine, bones, and teeth.
A number of lithium compounds have important pharmacological effects. Lithium carbonate is the most commonly used of the compounds. In the early nineteenth century, these compounds were used to treat gout (an illness characterized by a painful swelling of the joints), and lithium bromide was used to induce sleep.
In 1949, J. F. J. Cade of Australia was looking for toxic (poisonous) nitrogenous substances in the urine of mental patients by testing guinea pigs. He administered lithium salts to the animals in an attempt to increase the solubility of urates so that they would be secreted more readily in the urine. Lithium carbonate, one of the salts, made the animals sleepy. He then gave lithium carbonate to severely agitated or manic patients. He reported that this treatment seemed to have a dramatic effect on mania.
Lithium carbonate was not accepted for use in the United States until 1970, however, owing to fears about its safety. These fears existed because doctors in the 1940s had used lithium chloride as a salt substitute in heart patients and others who were chronically ill. This was ill-advised and led to severe toxicities (poisonous reactions) and death.
Today lithium carbonate successfully controls the wild mood swings from depression to elation observed in manic-depressive illness (also known as bipolar disorder). It produces the most dramatic therapeutic improvement of any drug used in psychiatry.