Isoeugenol

Isoeugenol must be declared in the EU, Northern Ireland and Great Britain once it crosses the threshold.

Identity

Name in the ingredient list	Isoeugenol
CAS / EC numbers	97-54-1 / EC 202-590-75932-68-3 / EC 227-678-25912-86-7 / EC 227-633-7
EU Annex III entry	73
GB Annex III entry	73

It predates the 2023 expansion; Reg (EU) 2023/1545 amended its entry (typically regrouping the covered isomer forms).

Note: Great Britain's assimilated entry lists a narrower set of CAS/EC forms (97-54-1, 5932-68-3), because GB never adopted the 2023 regrouping. The name to print is the same.

When it must appear on the label

Isoeugenol may be present as a constituent of essential oils or fragrance compounds. It must be named individually in the ingredient list when its total concentration in the finished product exceeds 0.001% in leave-on products (lotions, balms) or 0.01% in rinse-off products (soap, shower gel), summed across every fragrance source in the recipe. Below the threshold it stays within the collective term "Parfum".

United States: no individual fragrance-allergen labelling is in force yet (MoCRA rulemaking pending); fragrance is declared collectively as "Fragrance".

Common questions

Do I have to list Isoeugenol on my label?

Isoeugenol must be declared in the EU, Northern Ireland and Great Britain once it crosses the threshold. It must be named individually once it exceeds 0.001% of a leave-on product or 0.01% of a rinse-off product, summed across every fragrance source in the recipe. Below that it stays inside the collective term "Parfum".

What is the CAS number for Isoeugenol?

Isoeugenol is listed under CAS 97-54-1, 5932-68-3, 5912-86-7 (EC 202-590-7, 227-678-2, 227-633-7), Annex III entry 73.

Sources

Commission Regulation (EU) 2023/1545 (OJ L 188, 27.7.2023), as corrected by the corrigendum of 11.11.2025, Annex (EUR-Lex)
Assimilated Regulation (EC) No 1223/2009, Annex III, as it applies in Great Britain, entries carrying the individual-declaration condition (legislation.gov.uk)

Transcribed from the official texts linked above and source-audited against them; a labelling reference, not safety advice. You remain responsible for your product's compliance.

Rule tables last checked 21 August 2026.