Aluminium

Aluminium (E173) is a metallic silver-grey surface colorant used exclusively on the outer coating of confectionery dragees, chocolate decorations, and similar decorative applications. It gives products a metallic, lustrous finish. Only food-grade aluminium powder meeting strict purity specifications is permitted; use is restricted to surface application only, not to the interior of food products.

JECFA's ADI for aluminium is "not allocated," reflecting that the available data were insufficient to establish a specific numerical value for aluminium used as a food additive. A provisional tolerable weekly intake (PTWI) of 2 mg per kilogram body weight per week for total aluminium exposure from all sources was established in 2006 — a significantly reduced figure from earlier assessments, reflecting concerns about cumulative exposure. Chronic high dietary aluminium has been associated with neurotoxicity and possible links to neurological conditions, though evidence at typical dietary levels remains debated.

Aluminium as a food colourant (E173) is permitted in the EU, restricted to decorative surface applications on confectionery. It is not generally permitted as a food colourant in the US or Australia. The amounts ingested from surface-decorated confectionery are minimal and typically well within total aluminium exposure budgets. Consumers should consider total aluminium exposure from all dietary sources — including naturally occurring aluminium in food, tap water, cookware leaching, and antacid medications — rather than focusing solely on E173.