ALPHA-ISOMETHYL IONONE
ALPHA-ISOMETHYL IONONE is identified as a fragrance allergen subject to mandatory label declaration under Regulation (EC) No 1223/2009.
Regulatory data checked on 2026-09-05. The legal status follows Regulation (EC) No 1223/2009 and its annexes; the substance is identified from the European Commission's CosIng database.
About the ingredient
3-Methyl-4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-2-one; Methyl-gamma-ionone; gamma-Methylionone
EU regulatory status
Annex of Regulation (EC) No 1223/2009: III/90
What entry III/90 of the Regulation says
3-Methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-one
Source: the European Commission's official CosIng database and Regulation (EC) No 1223/2009 of the European Parliament and of the Council on cosmetic products. How we assess ingredients — full methodology.
- View the entry in the CosIng database (European Commission)
- Open Regulation 1223/2009 in EUR-Lex
- Check the chemical profile in PubChem
Last updated:
Functions in cosmetics
Frequently asked questions
Is ALPHA-ISOMETHYL IONONE safe in cosmetics?
ALPHA-ISOMETHYL IONONE is a fragrance allergen that must be named in the ingredient list once it exceeds 0.001% in leave-on products or 0.01% in rinse-off products. Regulation (EU) 2023/1545 extended this labelling duty well beyond the original 26 substances.
In which annex of Regulation 1223/2009 does ALPHA-ISOMETHYL IONONE fall?
ALPHA-ISOMETHYL IONONE falls under reference III/90 in the annexes of Regulation (EC) No 1223/2009 on cosmetic products. An annex entry may name a substance directly or cover it as part of a broader category. The first part (Roman numeral) indicates the annex: II – prohibited substances, III – substances restricted by conditions, IV – permitted colorants, V – permitted preservatives, VI – permitted UV filters.
What functions does ALPHA-ISOMETHYL IONONE perform in cosmetics?
According to the European Commission's CosIng database, ALPHA-ISOMETHYL IONONE performs the following functions in cosmetics: PERFUMING, SKIN CONDITIONING. Functions are defined in the CosIng glossary and describe the technological role of a substance in the finished product.
Are there Safety Gate alerts concerning ALPHA-ISOMETHYL IONONE?
We found 4 recent alerts in the EU Safety Gate database in which ALPHA-ISOMETHYL IONONE appears in the risk description or on the ingredient list of a recalled cosmetic. The full list and details of each alert are below in the Safety Gate alerts section.
Safety Gate alerts mentioning this ingredient
We found 4 recent EU Safety Gate alerts that mention ALPHA-ISOMETHYL IONONE in the hazard description or ingredient list.