Erythrosine

Erythrosine (E127) is a synthetic xanthene dye that produces a distinctive cherry-red or pink shade in food products. Chemically it is the disodium salt of 2',4',5',7'-tetraiodofluorescein — notably, it contains four iodine atoms per molecule, representing approximately 58% iodine by mass. This high iodine content has significant implications for its metabolism and regulatory status. It is used in glazed cherries, cocktail cherries, and some processed fish products.

JECFA established an ADI for erythrosine of 0–0.1 mg per kg body weight per day in 1987 — one of the lowest ADI values among approved food colours. For a 60 kg adult this represents just 6 mg per day from food additive sources. The same value of 0.1 mg/kg body weight per day has been confirmed by EFSA in the OpenFoodTox 3.0 dataset. The low ADI reflects concerns about erythrosine's high iodine content and its potential to affect thyroid function at elevated exposures.

Erythrosine is banned as a food colour in most applications in the European Union and tightly restricted in many other jurisdictions due to concerns about its iodine load and thyroid effects. The EU ban on erythrosine in food dates to 1994. It is permitted in the United States (as FD&C Red No. 3) for certain applications including maraschino cherries. Consumers with thyroid conditions or iodine sensitivities should be particularly aware of erythrosine's presence in any products that still contain it. Its global use is very limited compared to other red food colours.