The rules are transcribed from the official regulatory texts and source-audited against them. The tool assists you; check the review notes before printing a label for sale.

Fragrance allergens / Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde

Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde

Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde is declarable in Great Britain only. The EU removed it from the list, but that change is not applied to GB, so a product sold in GB must still declare it.

Identity

Name in the ingredient listHydroxyisohexyl 3-Cyclohexene Carboxaldehyde
CAS / EC numbers51414-25-6 / EC 257-187-931906-04-4 / EC 250-863-4
GB Annex III entry79

Transcription note: GB-only: HICC/Lyral was removed from the EU list (Reg 2017/1410) but that change is not applied to GB (post-IP-completion-day), so GB still requires it. COMPLIANCE-REVIEW: confirm no later GB SI has since banned it.

When it must appear on the label

Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde 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 Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde on my label?

Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde is declarable in Great Britain only. The EU removed it from the list, but that change is not applied to GB, so a product sold in GB must still declare it. 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 Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde?

Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde is listed under CAS 51414-25-6, 31906-04-4 (EC 257-187-9, 250-863-4).

Sources

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.