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Saccharin



Saccharin[1]
IUPAC name 1,1-Dioxo-1,2-benzothiazol-3-one
Other names Benzoic sulfinide
E954
Identifiers
CAS number 81-07-2
PubChem 5143
SMILES C1=CC=C2C(=C1)C(=O)NS2(=O)=O
Properties
Molecular formula C7H5NO3S
Molar mass 183.1845
Appearance White crystalline solid
Density 0.828 g/cm3
Melting point

228.8-229.7 °C

Solubility in water 1 g per 290 mL
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Saccharin[2] is the oldest artificial sweetener. The basic substance, benzoic sulfinide, was produced in 1878 by Constantin Fahlberg, a chemist working on coal tar derivatives in Ira Remsen's laboratory at the Johns Hopkins University, and it was he who, accidentally, discovered its intensely sweet nature. Fahlberg and Remsen published articles on benzoic sulfinide in 1879 and 1880. In 1884, now working on his own in New York City, Fahlberg applied for patents, in several countries, describing methods of producing this substance that he named saccharin. Fahlberg would soon grow wealthy, while Remsen merely grew irate, believing that he deserved credit for substances produced in his laboratory. On the matter, Remsen commented, "Fahlberg is a scoundrel. It nauseates me to hear my name mentioned in the same breath with him."

In the European Union, saccharin is also known under the E number (additive code) E954.

Saccharin is about 300 times as sweet as sucrose, but has an unpleasant bitter or metallic aftertaste, especially at high concentrations. Unlike the newer artificial sweetener aspartame, saccharin is stable when heated, even in the presence of acids. It does not react chemically with other food ingredients, and stores well. Blends of saccharin with other sweeteners are often used to compensate for each sweetener's weaknesses. A 10:1 cyclamate:saccharin blend is common in countries where both these sweeteners are legal; in this blend, each sweetener masks the other's off-taste. Saccharin is often used together with aspartame in diet soda, so that some sweetness remains should the fountain syrup be stored beyond aspartame's relatively short shelf life. Saccharin was an important discovery, especially for diabetics, as it goes directly through the human digestive system without being digested. It does not affect blood insulin levels, and has effectively no food energy.

In its acidic form, saccharin is not particularly water-soluble. The form used as an artificial sweetener is usually its sodium salt. The calcium salt is also sometimes used, especially by people restricting their dietary sodium intake. Both salts are highly water-soluble: 0.67 grams per milliliter water at room temperature.[3][4]

Contents

Saccharin and the US Government

Starting in 1907, the USDA began investigating saccharin. Problems with saccharin and the USDA have not been resolved since then. The initial series of investigations begun by the USDA in 1907 were a direct result of the Pure Food and Drug Act. The act, passed in 1906, came after a storm of health controversies influenced the American public, bringing to light many of the health issues surrounding the meat-packing industry.

Harvey Wiley was one particularly well-known figure involved in the investigation of saccharin. Wiley, then the director of the bureau of chemistry for the USDA, had suspected saccharin to be damaging to human health. This opinion clashed strongly with President Theodore Roosevelt who rejected the notion that saccharin was dangerous, stating, "Anybody who says saccharin is injurious is an idiot." Wiley first battled saccharin in 1908. In 1911, the Food Inspection Decision 135 stated that foods containing saccharin were adulterated. However in 1912, Food Inspection Decision 142 stated that saccharin was not harmful. The government's stance on saccharin has continued to waver ever since. In 1969, files were discovered from the Food and Drug Administration investigations from 1948 and 1949 and this stirred more controversy. These investigations, which had originally argued against saccharin use, were shown to prove little about Saccharin being harmful to human health. In 1972, the USDA made an attempt to completely ban the substance from being used in anything.[5]

History

Although saccharin was commercialized not long after its discovery, it was not until sugar shortages during World War I that its use became widespread. Its popularity further increased during the 1960s and 1970s among dieters, since saccharin is a calorie-free sweetener. In the United States saccharin is often found in restaurants in pink packets; the most popular brand is "Sweet'N Low". A small number of soft drinks are sweetened with saccharin, the most popular[citation needed] being the Coca-Cola Company's cola drink Tab, introduced in 1963 as a diet cola soft drink.

Chemistry

The image to the right shows the chemical structure of saccharin. It has the chemical formula C7H5NO3S.

Saccharin can be produced in various ways.[6] Remsen & Fahlberg's original route starts with toluene, but yields from this starting point are low. In 1950, an improved synthesis was developed at the Maumee Chemical Company of Toledo, Ohio. In this synthesis, anthranilic acid successively reacts with nitrous acid, sulfur dioxide, chlorine, and then ammonia to yield saccharin. Another route begins with o-chlorotoluene.[7]

Saccharin is an acid with a pKa of about 2.[8][9]

Saccharin and cancer

 

  There have been worries about the safety of saccharin since its introduction. As early as 1907 saccharin came under the examination and scrutiny of the United States Department of Agriculture (USDA). As Theodore Roosevelt took the office of the President of the United States, an intense debate questioned the safety of the artificial sweetener. Sparked by the Pure Food and Drug Act of 1906, saccharin was investigated by the "poison squad," led by Harvey W. Wiley's assertion that it caused digestive problems (Kauffman and Priebe pg 557). Commenting on the questionable safety of saccharin, Theodore Roosevelt (who was at the time dieting on orders from his physician to lower his risk for diabetes) once said directly to Wiley, "Anyone who thinks saccharin is dangerous is an idiot". The controversy continued with the prohibition of saccharin during the Taft administration. Studies and legal controversy fueled the heated debate of this prohibition until the outbreak of the first World War. During World War I, the United States experienced a sugar shortage; the prohibition of saccharin was lifted to balance the demand for sugar. The wide spread production and use of saccharin continued through World War II, again alleviating the shortages during war time but immediately slowing at the war's end.[10]

Throughout the 1960s, various studies suggested that saccharin might be an animal carcinogen. Concern peaked in 1977, after the publication of a study indicating an increased rate of bladder cancer in rats fed large doses of saccharin. In that year, Canada banned saccharin while the United States Food and Drug Administration also proposed a ban. At the time, saccharin was the only artificial sweetener available in the U.S., and the proposed ban met with strong public opposition, especially among diabetics. Eventually, the U.S. Congress placed a moratorium on the ban, requiring instead that all saccharin-containing foods display a warning label indicating that saccharin may be a carcinogen.

Many studies have since been performed on saccharin, some showing a correlation between saccharin consumption and increased frequency of cancer (especially bladder cancer) and others finding no such correlation. No study has ever shown a clear causal relationship between saccharin consumption and health risks in humans at normal doses, though some studies have shown a correlation between consumption and cancer incidence.[11] Furthermore, the biological mechanism believed to be responsible for the rat cancers has been shown to be inapplicable to humans because of differences in urine composition between rats and humans. Many of the rat cancers may have been caused by contamination from the rubber plungers inside syringes[12]., the rubber seals used may corrode when mixed with certain fluids and the decomposed rubber may have caused the bad results[13]. Others blame certain types of rats like the Fischer 344 Rat which was discovered to be a poor example specimen for testing cancers when it was found out that these laboratory animals developed cancer spontaneously, when injected with pure water only.[14]

According to tradegroup operated saccharin.org, "Concerns over saccharin's safety were first raised twenty years ago after a flawed study that administered huge quantities of the sweetener to laboratory rats produced bladder tumors in rats. New and better scientific research has decisively shown that the earlier rat studies are not at all applicable to humans."

In 1991, after fourteen years, the FDA formally withdrew its 1977 proposal to ban the use of saccharin, and in 2000, the U.S. Congress repealed the law requiring saccharin products to carry health warning labels.

See also

Notes and references

  1. ^ Merck Index, 11th Edition, 8282.
  2. ^ The word saccharin (as above) has no final "e". The word saccharine, with a final "e", is much older and is an adjective meaning "sugary" – its connection with sugar means the term is used metaphorically, often in a derogative sense, to describe something "unpleasantly over-polite" or "overly sweet".[1] Both words are derived from the Greek word σάκχαρον (sakcharon, German ch sound), which ultimately derives from Sanskrit for sugar, sharkara (शर्करा), which literally means gravel[2]
  3. ^ Remsen, I. and Fahlberg, C., (1879). "Über die Oxydation des Orthotoluolsulfamids". Chemische Berichte 12: 469-473.
  4. ^ P. M. Priebem, G. B. Kauffman (1980). "Making governmental policy under conditions of scientific uncertainty: A century of controversy about saccharin in congress and the laboratory". Minerva 18: 556-574. doi:10.1007/BF01096124.
  5. ^ Preibe and Kauffman, 2,3,4,6,7
  6. ^ David J. Ager, David P. Pantaleone, Scott A. Henderson, Alan R. Katritzky, Indra Prakash, D. Eric Walters (1998). "Commercial, Synthetic Nonnutritive Sweeteners". Angewandte Chemie International Edition 37 (13-24): 1802-1817.
  7. ^ Bungard, 1967
  8. ^ WHO food additives series 17
  9. ^ pKa data compiled by R. Williams
  10. ^ Kauffman and Priebe pg 559-60
  11. ^ Weihrauch M. R., Diehl V. (2004). "Artificial sweeteners - do they bear a carcinogenic risk?". Annals of Oncology 15 (10): 1460-1465. doi:10.1093/annonc/mdh256.
  12. ^ Is Saccharin Safe? .: Ask. Dr. Hull
  13. ^ Is Saccharin Safe? .: Ask. Dr. Hull
  14. ^ Saccharin and Its Salts, International Agency for Research on Cancer
  • Paul M. Priebe and George B. Kauffman, “Making Government Policy under Conditions of Scientific Uncertainty: a Century of Controversy about Saccharin in Congress and the Laboratory,” Minerva, 18, 1980, 556-74.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Saccharin". A list of authors is available in Wikipedia.
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