Erythrosine, also known as E127 and Red No. 3, is an organoiodine compound, specifically a derivative of fluorone. It is a red-pink dye used for food coloring, cosmetics, hair coloring, pet products, and diverse industrial colorings.[
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History
The colorant was discovered by the Swiss chemist Karl Kussmaul at the University of Basel in 1876 and soon commercialized by the local Bindschedler & Busch company for dyeing wool and silk.
Its use as a food dye was legalized in the US by the Pure Food and Drug Act of 1906.
Production
Erythrosine is synthesized from resorcinol and phthalic anhydride, which are processed into fluorescein. Fluorescein then undergoes iodination, producing the bright red dye.
Uses
It is used as a food coloring,
Erythrosine is commonly used in sweets, such as some candies, and cherry, and in cake-decorating gels.
Safety assessment and regulation
Laboratory studies in the late 20th century suggested that "chronic erythrosine ingestion may promote thyroid tumor formation in rats via chronic stimulation of the thyroid by TSH" at concentrations of 4% erythrosine.
In the United States, laboratory evidence of carcinogenicity of extremely high doses of erythrosine renders it as "unsafe" under federal law by a provision called the Delaney Clause, despite conclusions by the federal Center for Food Safety and Applied Nutrition and Cancer Assessment Committee that the risk of developing cancer in humans is unlikely at the low erythrosine levels consumed as a food color.
Throughout the early 21st century, the World Health Organization and several national food safety agencies permitted use of erythrosine as a color additive when used in amounts below acceptable daily intake levels for certain foods, such as for packaged cherries; countries having restricted-use provisions were the European Union, United States, Canada, and Australia/New Zealand.
Since 1994,[ pet foods,]
In the United States, the use of erythrosine in cosmetics, topical drugs, some foods, and in all uses as its lake pigment variant have been banned by the Food and Drug Administration (FDA) since 1990.[ An October 2023 bill passed in the state of California also banned the use of erythrosine in foods (along with brominated vegetable oil, potassium bromate, and propylparaben), with enforcement beginning on 1 January 2027.]
In 2025, Health Canada stated that erythrosine "does not pose a health risk to the general Canadian population at the levels set out in the List of Permitted Food Colours."[
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Synonyms
Erythrosine B; Erythrosin B; Acid Red 51; C.I. 45430; FD&C Red No. 3; E127;
2',4',5',7'-Tetraiodo-3',6'-dihydroxy-spiro3H-isobenzofuran-1,9'-xanthen-3-one disodium salt; Tetraiodofluorescein sodium salt; Calcoid Erythrosine N; 2,4,5,7-Tetraiodo-3,6-dihydroxyxanthene-9-spiro-1'-3H-isobenzofuran-3'-one disodium salt; 2',4',5',7'-Tetraiodofluorescein, disodium salt; C.I. Food Red 14; Aizen Erythrosine; Tetraiodifluorescein, disodium salt; Spiroisobenzofuran-xanthen]-3-one, 3',6'-dihydroxy-2',4',5',7'-tetraiodo-, disodium salt.[
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Classification
It is listed under the following number systems:
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FD&C Red No. 3
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E number E127 (Food Red 14)
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Colour Index no. 45430 (Acid Red 51)
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Bureau of Indian Standards No. 1697
