E173 is a chemical compound, an ingredient included in the list of European food additives as dye and in the Colour Index International as a synthetic white dye composed mainly of aluminium with the number CI 77000.

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What it is used for and where
Cosmetics

Dye to avoid. It is an ingredient that makes the final product more attractive from an aesthetic point of view, but may pose a potential risk to human health with undesirable side effects especially when used continuously as it can be absorbed through the skin or mucous membranes.

Safety
Aluminium can interfere with different biological processes (cellular oxidative stress, calcium metabolism, etc.), so it can induce toxic effects in different organs and systems, and the nervous system is the main target of its toxicity.

CAS: 7429-90-5

Chemical name Aluminium

Molecular Formula    Al

EC number 231-072-3

UNII KZJ3T010RQ

DTXSID3040273