E121 – Citrus red No. 2

General Information

The additive E121 – Citrus Red 2 is a synthetic dye that belongs to the azo dye class. It has a bright red or orange-red color and is used exclusively to color the peel of oranges to make them more visually appealing.

Citrus Red 2 is chemically synthesized using azo compounds. Its production is based on a diazotization reaction followed by coupling with aromatic compounds. The raw materials typically include petrochemical derivatives such as naphthol and substituted anilines.

The chemical name of additive E121 is 1-(2,5-dimethoxy-phenylazo)-naphthalen-2-ol. Chemical formula: C₁₈H₁₆N₂O₃.

This dye is not soluble in water but is well soluble in fats and organic solvents.

Effects on the Body

Benefits of additive E121

Citrus Red 2 has no nutritional or dietary value. Its use is purely aesthetic. No positive health effects have been identified.

Risks of additive E121

This dye is considered potentially hazardous to health. Animal studies have shown that additive E121 may be carcinogenic at high doses and with prolonged consumption. Specifically, a link has been established between its intake and the development of tumors. For this reason, Citrus Red 2 is banned in many countries.

Since dye E121 is applied only to the peel of oranges, which is typically not consumed, its use is considered conditionally acceptable only in very limited cases. However, contact with the pulp or use of the peel (e.g., for zesting) may lead to the substance entering the human body.

The International Agency for Research on Cancer (IARC) classifies Citrus Red No. 2 as a Group 2B carcinogen, meaning it is "possibly carcinogenic to humans." This classification indicates limited evidence of carcinogenicity in humans and sufficient evidence in animals.

Uses

Additive E121 is used exclusively to color the peel of oranges grown in certain regions of the United States (notably Florida). Its use is permitted only when the fruit is sold whole and not intended for processing. In the broader food industry, including for other fruits or products, Citrus Red 2 is not used.

Legal Status

The use of additive E121 is banned in most countries around the world, including the European Union, Ukraine, and the United States (in all products except the mentioned oranges). In the U.S., its use is regulated by the Food and Drug Administration (FDA) and permitted only in strictly defined cases.

In April 2025, the FDA announced plans to gradually phase out synthetic food colorants in the United States, including Citrus Red No. 2, by the end of 2026.

In the EU and Ukraine, additive E121 is listed among banned food dyes due to its potential carcinogenic effect.