What is Erythrosine?
Erythrosine is an artificial red (cherry-pink) food colouring made from coal tar. It is an organic compound containing iodine and sodium. Erythrosine is also commonly referred to as red dye #3.
You might also hear erythrosine referred to as a xanthene dye. Xanthene dyes are a group of brilliant fluorescent dyes ranging in colour from yellow to pink to bluish red. They are called xanthene dyes because they all contain a xanthene molecule as their base. To see what this means, lets look at a xanthene molecule. The chemical formula for xanthene is C13H100, meaning there are 13 carbon atoms, 10 hydrogen atoms, and one oxygen atom. These atoms are arranged as shown:
Now, what does Erythrosine look like? The chemical formula for Erythrosine is C20H8I4O5. The following diagram shows the structure of the Erythrosine molecule. Can you see why it is called an xanthene dye?
Erythrosine is primarily used as a food dye. Some of the more common applications include:
- cocktail and candied cherries (Maraschino cherries)
- cake decorating gels
- used to colour pistachio shells
Erythrosine is not used frequently in the US because Allura red is used instead. In 2008, the Center for Science in the Public Interest petitioned the FDA for a complete ban on erythrosine but so far, no action as been taken. It can still be used in the US without restriction.
Health Issues / Side Effects:
There have been concerns that the iodine may affect thyroid. Some studies indicated a higher risk of thyroid tumors in rats.1
According to the World Health Organization, erythrosine intake in Canada was 10 times higher than in either the US or Japan.2 In all cases, the intake was below established acceptable daily intake amounts. Still, given the possible health risks, I’d like to be able to see what products contain erythrosine. Unfortunately, in Canada, companies only need to list “colour” in their ingredients.