E133: Brilliant Blue FCF

What is E133 (Brilliant Blue FCF)?

Brilliant Blue FCF (E133), known in the United States as FD&C Blue 1, is a synthetic blue food dye belonging to the triarylmethane class. It produces a distinctive bright blue color and is often combined with yellow dyes (such as tartrazine/E102) to create green shades. Brilliant Blue FCF is one of the most commonly used blue food colorings worldwide, particularly prevalent in American food products.

Source and Production

Brilliant Blue FCF is produced via chemical synthesis:

Raw Materials: Derived from aromatic hydrocarbons (coal tar or petroleum-based)
Condensation Reaction: Benzaldehyde-2-sulfonic acid is condensed with two equivalents of N-ethyl-N-(3-sulfobenzyl)aniline 3. Oxidation: The leuco base is oxidized to produce the blue chromophore 4. Salt Formation: Converted to disodium salt for water solubility 5. Purification: Filtration and drying to food-grade purity

The resulting dye is a bright blue powder that is highly water-soluble and stable across a wide pH range.

Common Uses in Food

E133 creates vibrant blue and green shades and is found in:

Ice cream and frozen desserts
Candy and confectionery
Soft drinks and sports beverages
Breakfast cereals
Cake icings and frostings
Popsicles and ice lollies
Condiments and sauces
Dairy products (flavored yogurts)
Medicines and dietary supplements
Cosmetics and personal care products

Health and Safety

Allergic and Hypersensitivity Reactions

Allergic reactions: Documented cases of urticaria (hives), angioedema, and anaphylaxis in sensitive individuals
Asthma: Can trigger respiratory symptoms in people with asthma
Cross-reactivity: Some cross-reactivity with other synthetic dyes and aspirin documented

Absorption and Metabolism Concerns

Brilliant Blue FCF is poorly absorbed from the gastrointestinal tract (most is excreted unchanged)
A small fraction is absorbed and metabolized; metabolites have not been extensively studied in humans
High doses in animal studies showed renal effects and organ weight changes

Potential Neurotoxicity

Some laboratory studies on isolated nerve cells suggested possible neurotoxic effects at high concentrations
These were observed at doses far exceeding normal dietary intake
Regulatory agencies consider current permitted levels safe

Regulatory Status

European Union: Permitted as E133; was historically banned in several EU countries (Belgium, France, Germany, Switzerland, Sweden, Austria) before EU harmonization
United States: Approved as FD&C Blue 1 by the FDA
Australia/New Zealand: Permitted
ADI: 6 mg/kg body weight/day (JECFA/EFSA)

Identification on Labels

Brilliant Blue FCF may appear as:

E133
Brilliant Blue FCF
FD&C Blue No. 1
Blue 1
Acid Blue 9
C.I. 42090

Alternatives

Natural blue coloring alternatives are limited but include:

Spirulina extract: Natural blue-green pigment from algae (increasingly used)
Butterfly pea flower extract: Vivid natural blue
Indigo (plant-derived): Traditional natural blue dye
Avoiding blue-colored foods by choosing naturally colored products

Conclusion

E133 (Brilliant Blue FCF) is a widely used synthetic blue dye with a moderate safety profile. While approved by major regulatory bodies, its history of bans in some European countries and documented potential for allergic reactions in sensitive individuals warrants attention. Most people can consume it at normal dietary levels without harm, but those with known sensitivities to synthetic dyes, asthma, or aspirin sensitivity should exercise caution.