What is FD&C Blue No. 2, Aluminum Lake?
FD&C Blue No. 2, Aluminum Lake (CAS Number: 16521-38-3) is a synthetic colorant approved for use in food products in the United States. The "lake" formulation refers to a process where the FD&C Blue No. 2 dye is chemically bonded to an aluminum hydroxide substrate, creating an insoluble pigment. This lake formulation differs from the water-soluble form of FD&C Blue No. 2, offering different functional properties in food applications.
Common Uses
FD&C Blue No. 2, Aluminum Lake is primarily used as a coloring agent in processed food products. Common applications include confectionery items, baked goods, beverages, ice cream, puddings, and other desserts. The lake formulation is particularly useful in products where oil-solubility or insolubility is desired, as it can be dispersed in fats and oils more effectively than water-soluble dyes. This makes it valuable for products with varied moisture content or those requiring stability in non-aqueous systems.
Safety Assessment
The FDA has not designated FD&C Blue No. 2, Aluminum Lake as Generally Recognized as Safe (GRAS), meaning it functions under FDA color additive regulations requiring pre-market approval. However, the agency maintains an extensive safety database on this additive. As of current records, there are zero adverse events reported to the FDA specifically linked to FD&C Blue No. 2, Aluminum Lake, and zero product recalls directly attributed to this colorant.
The underlying FD&C Blue No. 2 dye has been subject to numerous scientific studies evaluating its safety profile. Toxicological research has examined potential effects on animal models, including chronic toxicity and genotoxicity studies. The European Food Safety Authority (EFSA) has also reviewed blue colorants and maintains approval for similar colorants in European markets under different nomenclature (E131 for indigo carmine, for example).
The aluminum hydroxide substrate component is derived from a food additive already permitted in multiple contexts. The chemical bonding process used to create the lake form is standardized and monitored for quality and consistency. Food manufacturers must adhere to strict specifications regarding the purity and composition of the final lake product.
Regulatory Status
In the United States, FD&C Blue No. 2, Aluminum Lake is an approved color additive regulated under 21 CFR 73.250. This approval comes with specific usage restrictions and permitted food categories. The FDA's Color Additives Status List categorizes it as approved for use in foods with defined limitations on application rates and product types.
The additive is subject to batch certification requirements by the FDA's Color Certification Program, ensuring quality control and purity of commercial products. Manufacturers must provide documentation demonstrating compliance with established specifications before products can be marketed.
International regulations vary. While approved in the United States, food regulations in other countries may differ. The European Union, for instance, uses different nomenclature and has distinct approval processes for color additives.
Key Studies
Scientific literature on FD&C Blue No. 2 includes multiple toxicological assessments conducted over several decades. Chronic feeding studies in laboratory animals have been primary tools for safety evaluation. These studies typically examine parameters such as organ weights, clinical chemistry, hematology, and histopathological findings at various dose levels.
Genotoxicity studies have evaluated the dye's potential to cause genetic damage. Carcinogenicity studies examining long-term exposure at relevant dietary levels have also been conducted. The collective body of evidence has supported continued regulatory approval.
Research on the aluminum hydroxide substrate separately confirms its safety profile as a food additive used in other contexts such as anti-caking agents. The combination in lake form has been evaluated for potential changes in toxicological properties.