FD&C Red No. 40

Allura Red AC

Names
IUPAC name Disodium 6-hydroxy-5-[(2-methoxy-5-methyl-4-sulfophenyl)azo]-2-naphthalenesulfonate
Other names Allura Red; Food Red 17; C.I. 16035; FD&C Red 40; E129; 2-Naphthalenesulfonic acid, 6-hydroxy-5-((2-methoxy-5-methyl-4-sulfophenyl)azo)-, disodium salt, Food Red 17, C.I. 16035, FD&C Red 40
Identifiers
CAS Number	25956-17-6 Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL174821 N
ChemSpider	11588224 Y
ECHA InfoCard	100.043.047
E number	E129 (colours)
PubChem CID	6093299
UNII	WZB9127XOA Y
InChI InChI=1S/C18H16N2O8S2.2Na/c1-10-7-14(16(28-2)9-17(10)30(25,26)27)19-20-18-13-5-4-12(29(22,23)24)8-11(13)3-6-15(18)21;;/h3-9,21H,1-2H3,(H,22,23,24)(H,25,26,27);;/q;2*+1/p-2/b20-19+;; Y Key: CEZCCHQBSQPRMU-LLIZZRELSA-L Y InChI=1/C18H16N2O8S2.2Na/c1-10-7-14(16(28-2)9-17(10)30(25,26)27)19-20-18-13-5-4-12(29(22,23)24)8-11(13)3-6-15(18)21;;/h3-9,21H,1-2H3,(H,22,23,24)(H,25,26,27);;/q;2*+1/p-2/b20-19+;; Key: CEZCCHQBSQPRMU-JGGVBICHBN
SMILES [Na+].[Na+].COc3cc(c(C)cc3/N=N/c1c2ccc(cc2ccc1O)S([O-])(=O)=O)S([O-])(=O)=O
Properties
Chemical formula	C18H14N2Na2O8S2
Molar mass	496.42 g·mol−1
Appearance	Red powder
Melting point	> 300 °C (572 °F; 573 K)
Hazards
NFPA 704	1 1 0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Allura Red AC is a red azo dye that goes by several names. It is used as a food dye and has the E number E129.

It is usually supplied as its dark red sodium salt, but can also be used as the calcium and potassium salts. These salts are soluble in water. In solution, its maximum absorbance lies at about 504 nm.

Allura Red AC is a popular dye throughout the world. Annual production in 1980 was greater than 2.3 million kilograms.

The European Union approves Allura Red AC as a food colorant, but EU countries' local laws banning food colorants are preserved. In the United States, Allura Red AC is approved by the FDA for use in cosmetics, drugs, and food. When prepared as a lake it is disclosed as Red 40 Lake or Red 40 Aluminum Lake. It is used in some tattoo inks and is used in many products, such as soft drinks, children's medications, and cotton candy. It is by far the most commonly used red dye in the United States, completely replacing amaranth (Red 2) and also replacing erythrosine (Red 3) in most applications due to the potential health effects of the two dyes.

Allura Red has been heavily studied by food safety groups in North America and Europe, but remains in wide use and wide acceptance.

The UK FSA commissioned a study of six food dyes (Tartrazine, Allura Red, Ponceau 4R, Quinoline Yellow WS, Sunset Yellow, Carmoisine (dubbed the "Southampton 6")), and sodium benzoate (a preservative) on children in the general population, who consumed them in beverages. The study found "a possible link between the consumption of these artificial colours and a sodium benzoate preservative and increased hyperactivity" in the children; the advisory committee to the FSA that evaluated the study also determined that because of study limitations, the results could not be extrapolated to the general population, and further testing was recommended".