Saccharin

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.

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 Page 690  |  Top of Article
Benzoic sulfinide. Red atoms are oxygen; white atoms are hydrogen; black atoms are carbon; blue atom is nitrogen; and yellow atom is sulfur. Gray sticks indicate double bonds. Striped sticks show a benzene ring. Publishers Resource Group 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 Page 691  |  Top of Articleof 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.

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.

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.

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 Page 693  |  Top of Articlewith large quantities of saccharin are likely to be concerned about such safety problems, however.