3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One

INCI: 3-ETHYL-2-HYDROXY-4-METHYLCYCLOPENT-2-EN-1-ONE

CAS Number
21835-01-8 (Corylone / Maple Lactone) — *confirm via CosIng*
Function
Perfuming/Fragrance — sweet, caramellic, maple-like character
Safety Rating
GOOD

Regulatory Status

🇪🇺 EU Status permitted
🇺🇸 US Status permitted
US Notes Permitted; also used as a food flavoring (FEMA listed)

For full compliance data across 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
not established
Dermal Absorption
moderate
Sensitization
none

Calculate MoS for your specific formulation with the MoS Calculator.

Expert Verdict

α,β-Unsaturated ketone structural alert — theoretically reactive, but the 2-hydroxy group stabilizes the molecule. RIFM/JECFA evaluations have found it acceptable at intended use levels. Verify purity specifications.

⚠️
Concern Level: Low

Regulatory Flags

fragrance-component jecfa_safe

Frequently Asked Questions

Is 3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One safe in cosmetics?

α,β-Unsaturated ketone structural alert — theoretically reactive, but the 2-hydroxy group stabilizes the molecule. RIFM/JECFA evaluations have found it acceptable at intended use levels. Verify purity specifications. The EU classifies 3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One as "permitted". Safety rating: GOOD.

Is 3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One allowed in the EU?

3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.

What does 3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One do in cosmetics?

3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One functions as: Perfuming/Fragrance — sweet, caramellic, maple-like character. It is classified as a cosmetic ingredient in our database. CAS number: 21835-01-8 (Corylone / Maple Lactone) — *confirm via CosIng*.

What is the Margin of Safety for 3-Ethyl-2-Hydroxy-4-Methylcyclopent-2-En-1-One?

not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.

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