Ingredient Directory
Medium ConcernVegan Evaluator Flag

Alpha-Isomethyl Ionone

(E)-3-methyl-4-(2,6,6-trimethylcyclohex-2-en-1-yl)but-3-en-2-one

Safety Flags
Allergen: Yes - EU Annex III fragrance allergen
Safety Notes

EU Annex III fragrance allergen; synthetic violet/iris aroma chemical; commonly used in personal care products for violet-like floral notes; moderate sensitization potential; IFRA restricts in leave-on skin care applications

Function & Common Use

Function

Fragrance / Perfuming / Aroma Chemical

Category

Fragrance Materials

Common In

Violet and iris-type perfumes, floral fragrances, fine fragrance, body care, personal care

Origin

Synthetic

Concentration Limits

India (CDSCO)

Declaration required above 0.001% leave-on / 0.01% rinse-off

EU Cosmetics Reg.

Declaration threshold: 0.001% leave-on / 0.01% rinse-off (EU Reg 2023/1545)

US FDA (21 CFR)

None (FEMA GRAS); IFRA-guided

Korea (MFDS)

None specific

Format restriction: EU mandatory declaration when above threshold; IFRA 49th Amendment limits by category

Baby restriction: No

Pregnancy: No

IFRA: Yes - IFRA 49th Amendment; Category 4 (body leave-on): 0.3%; Category 5A (face leave-on): 0.2%; Category 1 (fine fragrance): 5.0%; rinse-off: higher limits

Frequently Asked Questions

Is Alpha-Isomethyl Ionone safe to use in skincare?

Alpha-Isomethyl Ionone has a Medium concern rating. EU Annex III fragrance allergen; synthetic violet/iris aroma chemical; commonly used in personal care products for violet-like floral notes; moderate sensitization potential; IFRA restricts in leave-on skin care applications

Is Alpha-Isomethyl Ionone allowed in India?

Alpha-Isomethyl Ionone is currently classified as "Permitted" under Indian cosmetics regulations. The maximum permitted concentration is Declaration required above 0.001% leave-on / 0.01% rinse-off.

What is Alpha-Isomethyl Ionone used for in cosmetics?

Alpha-Isomethyl Ionone functions as: Fragrance / Perfuming / Aroma Chemical. It is commonly found in: Violet and iris-type perfumes, floral fragrances, fine fragrance, body care, personal care.

Can Alpha-Isomethyl Ionone cause an allergic reaction?

Yes. Alpha-Isomethyl Ionone has an allergen flag (Yes - EU Annex III fragrance allergen). If you have sensitive skin or known fragrance/contact allergies, patch-test products containing this ingredient before full use.

Is Alpha-Isomethyl Ionone safe for babies?

Alpha-Isomethyl Ionone has baby/child restrictions: No. Avoid using products containing this ingredient on infants unless specifically formulated and labelled for baby use.

TCS Assessment
Medium Concern
Data Confidence
High
Based on peer-reviewed safety data, regulatory status, and expert review by The Clean Sheet panel.

Regulatory Status

India (CDSCO)
Permitted
EU
Permitted
US FDA
FEMA GRAS
Korea (MFDS)
Permitted
Australia (TGA)
Permitted
Canada (NHPID)
Permitted

EU Annex: Annex III (fragrance allergen - declaration required)

Identifiers

CAS127-51-5
EC204-846-3

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