Erythrosine, C₂₀H₆I₄O₅ is a reddish-pink synthetic dye. It is most popularly used as a food coloring agent and a host of other applications such as printing inks, a dental plaque disclosing agent, a biological stain and a radiopaque medium.

It is used drugs and cosmetics, cocktails, tinned fruits, biscuits, chocolate, dressed crabs, garlic sausage, luncheon meat, salmon spread pate, scotch eggs, stuffed olives, sweets, bakery and snack foods.
The chemical composition of Erythrosine is as follows:

No.	Molecular Description	Composition
1)	Total colour/Assay, percent by Mass, Min.	87
2)	Water-insoluble matter, percent by mass, Max.	0.2
3)	Combined ether extracts, percent by mass, Max.	0.2
4)	Subsidiary dyes, percent by mass, Max. Mono- iodo-fluorescein. Lower iodinated fluorescein.	04.00 N/A N/A
5)	Dye intermediates, percent by mass, Max. Tri iodo resorcinol. 2 (2,4 -di- hydroxy-3,5-di-iodobenzoyl) benzoic acid.	0.2 0.2
6)	In organic iodide percent by mass as sodium Iodine, Max.	0.1
7)	Fluorescein mg/kg, Max.	20
8)	Lead, mg/kg, Max.	10
9)	Arsenic, mg/kg, Max.	3
10)	Heavy metals (as pb), mg/kg, Max.	40
11)	Mercury, mg/kg, Max.	1
12)	Cadmium, mg/kg, Max.	1