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Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde
Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde · Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde (Lyral) · Hydroxymethylpentylcyclohexenecarboxaldehyde
A lily-of-the-valley fragrance, sold as Lyral, prohibited in EU cosmetics since the 2019 phase-out.
What it does
Hydroxyisohexyl 3-cyclohexene carboxaldehyde — HICC, sold as Lyral — is a synthetic fragrance with a lily-of-the-valley note. It was one of the most frequent causes of fragrance contact allergy in European patch-test data, and the SCCS concluded it should not be used in cosmetics at all. Commission Regulation (EU) 2017/1410 moved it to the EU prohibited list: no new EU products from 23 August 2019 and none on EU shelves from 23 August 2021. It is not prohibited in the United States, so a US-market or pre-ban product can still list it. Its role was scent only.
The evidence, graded
expert consensusTreemoss (Evernia furfuracea), oakmoss (Evernia prunastri), and HICC (Lyral) were the three most frequently positive of the EU's 26 fragrance allergens in a 1,508-patient patch-test series. Commission Regulation (EU) 2017/1410 prohibited HICC, plus atranol and chloroatranol — the constituents behind most oakmoss and treemoss allergy — from 23 August 2019 for new EU products and 23 August 2021 for stock already on shelves.Heisterberg 2011 · Contact Dermatitis ↗ Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
lyral, hicc, hydroxymethylpentylcyclohexenecarboxaldehyde
This page is public and indexed on purpose (unlike profiles and drops, which are unlisted) — it’s the citation behind shared ingredient cards, and it should be findable.
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