Aluminium E173
metallic — Primarily metallic.
Aluminium (metallic)
CAS: 7429-90-5
Factual Regulatory Reference
This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.
What Is Aluminium?
Aluminium (E173) is the metallic element used as a silver-colored surface coating agent on confectionery items such as dragées, sugar-coated nuts, and cake decorations, where it provides a bright metallic appearance. Only the metallic form used as a food colorant is covered by E173 authorization — aluminium in other forms (salts, compounds) is regulated separately. In the EU, E173 is authorized exclusively for use as a surface coating agent on confectionery for decoration purposes under Regulation (EC) No 1333/2008. There has been growing scientific interest in aluminium intake from all dietary sources given concerns about its neurotoxic potential at high doses, though regulatory agencies have focused on total aluminium exposure rather than the metallic surface coating form specifically. EFSA set a tolerable weekly intake (TWI) for aluminium compounds in 2008.
? Did You Know?
Aluminium occurs naturally in Bauxite ore (aluminium oxide) and Feldspar minerals. Many people consume it daily without realizing it's also a listed food additive.
Beyond food, Aluminium is also used in cosmetics, medicine, industrial applications, household products. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.
Regulatory opinions differ: Aluminium is approved in EU, JAPAN, CANADA but banned in USA. This reflects different risk assessment philosophies between regions.
Regulatory Analysis
Metallic aluminium (E173) occupies a narrow regulatory niche: EU and Japan authorize it exclusively for external surface decoration on confectionery, premised on the argument that dermal contact with a metallic coating results in negligible oral absorption. The FDA does not approve E173 for food use; Australia also prohibits it. EFSA's concern is not specifically with E173 but with cumulative dietary aluminium exposure across all food additive sources (E173, E520, E541, E554, etc.), for which a TWI of 1 mg/kg body weight per week was established in 2008 and maintained in 2011. The 2023 EFSA group re-evaluation of aluminium-containing additives underscored that some population subgroups — particularly children with high consumption of products using multiple aluminium-containing additives — may approach or exceed the TWI. The EU's authorization of E173 is thus conditional on the broader context of total aluminium exposure management.
Detailed Regulatory Assessment
European Union (EFSA)
Only for external decoration of confectionery and cake decorations. Not permitted for internal use.
Official EFSA LinkUnited States (FDA)
Not approved for use as a food colorant in the United States
Japan (MHLW)
Restricted to external surface decoration only
Acceptable Daily Intake (ADI)
International Standard (JECFA)
mg/kg body weight per day
European Standard (EFSA)
Natural Occurrence
Aluminium is the most abundant metal in Earth's crust but never occurs naturally in pure metallic form. Food-grade metallic aluminium is produced industrially from bauxite ore.
Manufacturing
Produced through the Hall-Héroult process: extracting aluminium from bauxite ore through electrolysis. The metal is then ground into fine powder or flakes for use as a surface colorant in food decoration.
Applications Beyond Food
Used in eye shadows, nail polish, and other cosmetics for metallic/shimmering effects.
Used as a coating for pills and tablets for visual appeal.
Widely used in construction, transportation, packaging (foil), electrical applications, and aerospace.
Aluminium foil, cooking utensils, beverage cans.