Allura Red AC

Allura Red AC is a red azo dye that goes by several names, including FD&C Red 40.[1] It is used as a food dye and has the E number E129.

It is usually supplied as its 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.[2]:921

Allura Red AC is a popular dye used worldwide. Annual production in 1980 was greater than 2.3 million kilograms.[3]

The European Union approves Allura Red AC as a food colorant, but EU countries’ local laws banning food colorants are preserved.[4] 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 cotton candy, soft drinks, cherry flavored products, children’s medications, and dairy products. It is occasionally used to dye medicinal pills, such as the antihistamine fexofenadine, for purely aesthetic reasons.[5] 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 negative health effects of those two dyes.