Saccharin

OVERVIEW

Saccharin (SAK-uh-rin) is a synthetic compound whose water solutions are at least 500 times as sweet as table sugar. It passes through the human digestive system without being absorbed, so it has an effective caloric value of zero. It is used as a sugar substitute by diabetics or by anyone wishing to reduce their caloric intake.

KEY FACTS

OTHER NAMES:

Benzoylsulfonic imide; benzoic sulfimide

FORMULA:

C₇H₅NO₃S

ELEMENTS:

Carbon, hydrogen, nitrogen, oxygen, sulfur

COMPOUND TYPE:

Organic

STATE:

Solid

MOLECULAR WEIGHT:

183.18 g/mol

MELTING POINT:

228°C (442°F)

BOILING POINT:

Not applicable; decomposes

SOLUBILITY:

Slightly soluble in water; soluble in acetone and ethyl alcohol

Saccharin was the first artificial sweetener discovered. It was synthesized accidentally in 1879 when Johns Hopkins researchers Constantine Fahlberg (1850–1910) and Ira Remsen (1846–1927) were working on the development of new food preservatives. The story is told that Fahlberg accidentally spilled one of the substances being studied on his hand. Some time later, he noticed the sweet taste of the substance and began to consider marketing the product as an artificial sweetener. Fahlberg and Remsen jointly published a paper describing their work, but Fahlberg, without Remsen's knowledge, went on to request a patent for the discovery. He eventually became very wealthy from proceeds of the discovery, none of which he shared with Remsen. Remsen was later quoted as saying that "Fahlberg is a scoundrel. It nauseates me to hear my name mentioned in the same breath with him."

In spite of its sweet taste, saccharin was used at first as an antiseptic, a substance that stops the growth of or kills bacteria. Before long, however, its primary use became that of an artificial sweetener. By 1902, it had become so popular in Germany that the German sugar industry lobbied for laws limiting production of saccharin. Similar actions occurred in the United States in 1907 and, by 1911, the federal government restricted use of the compound to overweight invalids.

A shortage of sugar during World War I (1914–1918) led to the reintroduction of saccharin as a sweetening agent in foods. Another sugar shortage during World War II (1939–1945) saw a new boom in saccharin production. This time, the compound's popularity continued after the war ended.

Questions about saccharin's safety have been raised a number of times in the past. In 1969, for example, the sweetener cyclamate was found to be carcinogenic, and its use was banned in the United States. Doubts over saccharin's safety resurfaced, partly since it was often mixed with cyclamate in artificial sweeteners. In 1972, studies with rats suggested that saccharin too might be carcinogenic, and the U.S. Food and Drug Administration imposed restrictions on the sweetener's use. Later studies attempting to reproduce the 1972 research were largely unsuccessful, and the status of saccharin as a carcinogen remain unsettled.

In 1977, the Canadian government decided that sufficient evidence existed to ban the use of saccharin except for use with diabetics and others with special medical problems. The U.S. government considered taking similar action, but, after more than a decade of reviewing the evidence, decided to allow the use of saccharin among the general public. Nonetheless, the status of saccharin as a potential health hazard remains the subject of an active debate in the United States and other parts of the world.

HOW IT IS MADE

A number of methods are available for the synthesis of saccharin. For many years, the most popular process was one developed by the Maumee Chemical Company of Toledo, Ohio, in 1950. This method begins with anthranilic acid (o-aminobenzoic acid; C₆H₄(NH₂)COOH), which is treated successively with nitrous acid (HNO₂), sulfur dioxide (SO₂), chlorine (Cl₂), and ammonia (NH₃) to obtain saccharin. Another process discovered in 1968 starts with o-toluene, which is then treated with sulfur dioxide and ammonia to obtain saccharin.

Saccharin is not very soluble, so it is commonly made into its sodium or calcium salt (sodium saccharin or calcium saccharin), both of which readily dissolve in water, for use in drinks and cooking. Saccharin is often blended with other sweeteners to reduce its metallic aftertaste.

COMMON USES AND POTENTIAL HAZARDS

Saccharin is used almost exclusively as an artificial sweetener in food and drinks to replace sugar. Its lack of calories makes it suitable for diet products and for medical preparations designed for people who must reduce their caloric intake. It also finds some small application as a food preservative, as an antiseptic agent, and as a brightening agent in electroplating procedures.

Interesting Facts

• The chemical company Monsanto was founded in 1901 for the sole purpose of making saccharin. The company sold all of its product to a single company, the Coca-Cola company, founded in the late 1880s.

Words to Know

CARCINOGEN

A substance that causes cancer in humans or other animals.

ELECTROPLATING

A process by which a thin layer of one metal is deposited on top of a second metal by passing an electric current through a solution of the first metal.

SALT

A compound in which all of the hydrogen ions are replaced by metal ions.

SYNTHESIS

A chemical reaction in which some desired chemical product is made from simple beginning chemicals, or reactants.

Raw saccharin can be an irritant to the skin, eyes, and respiratory system. If ignited, it burns with the release of irritating fumes. Only individuals who come into contact with large quantities of saccharin are likely to be concerned about such safety problems, however.

FOR FURTHER INFORMATION

Henkel, John. "Sugar Substitutes: Americans Opt for Sweetness and Lite." FDA Consumer. December 1999. Available online at http://www.fda.gov/fdac/features/1999/699_sugar.html (accessed on November 3, 2005).

Nabors, Lyn O'Brien, ed. Alternative Sweeteners (Food Science and Technology). Third revision. London: Marcel Dekker, 2001.

Ruprecht, Wilhelm. "Consumption of Sweeteners: An Evolutionary Analysis of Historical Development." http://www.druid.dk/conferences/nw/paper1/ruprecht.pdf (accessed on November 3, 2005).

"Saccharin Sodium." J. T. Baker. http://www.jtbaker.com/msds/englishhtml/s0073.htm (accessed on November 3, 2005).

saccharin (C₇H₅NO₃S) Synthetic substance used as a substitute for sugar. It derives from toluene. In 1977, it was tenuously linked with some forms of cancer in humans, and is no longer widely used.

sac·cha·rin / ˈsak(ə)rən/ • n. a sweet-tasting synthetic compound, C₇H₅NO₃S, used in food and drink as a substitute for sugar.

saccharin A synthetic chemical, benzoic sulphimide, 300–550 times as sweet as sucrose. Soluble saccharin is the sodium salt. It has no food value, but is useful as a sweetening agent for diabetics and slimmers. Discovered in the USA in 1879.