Dulcin Explained

Dulcin is an artificial sweetener about 250 times sweeter than sugar, discovered in 1883 by the Polish chemist Józef (Joseph) Berlinerblau (27 August 1859 – 1935).^{[1] [2] [3] [4]} It was first mass-produced about seven years later. Although it was discovered only five years after saccharin, it never enjoyed the latter compound's market success. Nevertheless, it was an important sweetener of the early 20th century and had an advantage over saccharin in that it did not possess a bitter aftertaste.

Early medical tests marked the substance as safe for human consumption, and it was considered ideal for diabetics. However, an FDA study in 1951 raised many questions about its safety, resulting in its removal from the market in 1954 after animal testing revealed chronic toxicity.^[5] The FDA has also said that "the Federal Security Administrator regards these chemicals as poisonous substances which have no place in any food."^[6] In Japan, poisoning accidents by dulcin occurred frequently, and use of dulcin was forbidden in 1969.^[7]

Dulcin is also known by the names sucrol and valzin.^[8]

Preparation

Dulcin can be produced by the addition of potassium cyanate to p-phenetidine hydrochloride in an aqueous solution at room temperature.^[9]

An alternate way to make dulcin is by mixing urea and p-phenetidine hydrochloride to a mixture of hydrochloric acid and glacial acetic acid.^[10]

Toxicity

Dulcin is toxic to rats at 0.1% of the diet and above. At 0.1%, it causes a slight slowdown in growth; at 1.0%, the slowdown is evident alongside an increase in mortality and noticeable histological changes in liver, kidney, spleen, and heart.^[11]

See also

• 5-Nitro-2-propoxyaniline (P-4000), banned alongside dulcin by the FDA

Further reading

• Book: Hodges L . 1973 . Environmental pollution: a survey emphasizing physical and chemical principles . Holt, Rinehart and Winston Inc. . New York .
• Nanikawa R, Kotoku S, Yamada T . [Death from dulcin poisoning] . Nihon Hoigaku Zasshi = the Japanese Journal of Legal Medicine . 21 . 1 . 17–24 . January 1967 . 6068316 . Death from dulcin poisoning .
• Saito K . ズルチンによる食中毒事件 . Food poisoning case caused by dulcin . Japanese . Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi) . 1969 . 10 . 2 . 112–113 . 10.3358/shokueishi.10.112 . free .

Notes and References

1. Berlinerblau. Joseph. Ueber die Einwirkung von Chlorcyan auf Ortho- und auf Para-Amidophenetol. Journal für praktische Chemie. 1884. 30. 97–115. 2nd series. 10.1002/prac.18840300110. On the reaction of cyanogen chloride with ortho- and para-ethoxyaniline. German. ; see pp. 103–105. From p. 104: "Der Para-Aethoxyphenylharnstoff hat einen sehr süssen Geschmack." (Para-ethoxyphenylurea has a very sweet taste.)
2. Book: Hess. Ludwig. Über den Süßstoff Dulcin: seine Darstellung und Eigenschaften. 1921. Springer Verlag. Berlin & Heidelberg, Germany. 5–6. 9783642993923. 2nd. German. On the sweetener Dulcin: its preparation and properties.
3. 10.1021/ed064p954. Goldsmith, R.H. . 1987 . A tale of two sweeteners . Journal of Chemical Education . 64. 11 . 954–955. 1987JChEd..64..954G .
4. For a biography of Joseph Berlinerblau (with photographs), see:
   • Balasiewicz. Michał S.. Józef Berlinerblau i Jan Prot-Berlinerblau – współtwórcy polskiego przemysłu Polski niepodległej. Przemysł Chemiczny (Chemical Industry). 2013. 92. 9. 1692–1700. Józef Berlinerblau and Jan Prot-Berlinerblau – co-founders of Polish industry in independent Poland [i.e., the [[Second Polish Republic]] (1918–1939)]. Polish.
   • Reprinted in: "Józef Berlinerblau" in ewamaria2013 (2014) (in Polish)
   • Reprinted in: "Josef Berlinerblau" in Reunion 69 (2014) (in Polish)
5. Web site: 15FR321 Title 21 . January 18, 1950. FDA Federal Register . FDA . January 11, 2021. ... Notice to manufacturers and distributors of foods and drugs containing artificial sweeteners. Chronic-toxicity studies conducted by the Food and Drug Administration show/ that the artificial sweeteners dulcin (also known as sucrol, or 4-ethoxy-phenylurea, or paraphenetolcarbamide) and P-4000 (also known as l-n-propoxy amino4-nitrobenzene) cause injury to rats when fed at relatively low levels for approximately 2 years ...'.
6. https://s3.amazonaws.com/archives.federalregister.gov/issue_slice/1950/1/19/317-324.pdf#page=5 Food and Drug Administration- Title 21 chapter 1 Federal Register Archive
7. http://www.siyaku.com/uh/Shs.do?dspCode=W01W0104-3102 ズルチン標準品-Dulcin Standard
8. Book: Bender, David A.. A Dictionary of Food and Nutrition. 2005. Oxford University Press.
9. . 11 . 9 . 481–503 . 2003 . Synthesis of sulofenur analogs as antitumour agents: Part II . Youssef, Khairia M. . Al-Abdullah, Ebtihal . El-Khamees, Hamad .
10. Org. Synth. . 1951 . 31 . 11 . ARYLUREAS II. UREA METHOD p-ETHOXYPHENYLUREA . 11 . 10.15227/orgsyn.031.0011 .
11. Ikeda . Yoshio . Omori . Yoshihito . Oka . Shigenori . Shinoda . Mitsuo . Tsuzi . Kiyo . Studies on Chronic Toxicity of Dulcin . Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi) . 1960 . 1 . 1 . 62–69 . 10.3358/shokueishi.1.62 . free.