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Annex III Entry 131 11/09/2023

Alpha-Terpinene

p-Mentha-1,3-diene

Alpha-Terpinene is listed in Annex III and may only be used under the conditions shown in this record.

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Restricted substance— Annex III, EU Regulation 1223/2009
Entry: 131

Chemical identity and properties

PubChem 2D chemical structure for CAS 99-86-5
CAS 99-86-5PubChem CID 7462

Alpha-Terpinene

Alpha-terpinene is one of three isomeric monoterpenes differing in the positions of their two double bonds (beta- and gamma-terpinene being the others). In alpha-terpinene the double bonds are at the 1- and 3-positions of the p-menthane skeleton. It has a role as a volatile oil component and a plant metabolite. It is a monoterpene and a cyclohexadiene. — ChEBI

IUPAC name
1-methyl-4-propan-2-ylcyclohexa-1,3-diene
Molecular formula
C10H16
Molecular weight
136.23 g/mol
Exact mass
136.125200510 Da
XLogP3
2.8
Topological polar surface area
0.0 Ų
Hydrogen-bond donors
0
Hydrogen-bond acceptors
0
Covalent units
1
Defined stereocentres
0

Also known as

Terpilenep-Mentha-1,3-diene1-Isopropyl-4-methyl-1,3-cyclohexadiene1,3-Cyclohexadiene, 1-methyl-4-(1-methylethyl)-alpha-TerpinenFEMA No. 3558alphaTerpineneCHEBI:10334
16 more reported names
I24X278AP1RefChem:5530202-795-11-isopropyl-4-methylcyclohexa-1,3-diene1-Methyl-4-(1-methylethyl)-1,3-cyclohexadiene1-methyl-4-(propan-2-yl)cyclohexa-1,3-diene.alpha.-Terpinena-terpinene1-Methyl-4-isopropylcyclohexadiene-1,31-isopropyl-4-methyl-cyclohexa-1,3-diene.alpha.-Terpinene1-Methyl-4-isopropyl-1,3-cyclohexadiene1,3-Cyclohexadiene, 1-methyl-4-isopropyl-a-Terpinene (~90%)alpha -TerpineneCCRIS 9058
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External database identifiers

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Record details

Other restrictions

The presence of the substance shall be indicated in the list of ingredients referred to in Article 19(1), point (g), when its concentration exceeds: — 0,001 % in leave-on products — 0,01 % in rinse-off products. The peroxide value shall be less than 10 mmoles/L (This limit applies to the substance and not to the finished cosmetic product).

INCI glossary name

Alpha-Terpinene

Chemical name

p-Mentha-1,3-diene

Regulatory information

Regulation

(EU) 2023/1545

See every entry this act set

Identified ingredients

Key data

CAS
99-86-5
EC
202-795-1
Annex
III
Entry number
131

Inventory links for Alpha-Terpinene

Direct matches are limited for this record, so nearby entries from Annex III are shown as well.

Annex III 133
Nearby record in the same annex

Terpinolene

CAS: 586-62-9
EC: 209-578-0
Annex III 124
Nearby record in the same annex

Turpentine

CAS: 9005-90-7; 8006-64-2; 8052-14-0
EC: 232-688-5; 232-350-7; -

What Annex III means for Alpha-Terpinene

Alpha-Terpinene is a restricted substance under Annex III of EU Cosmetics Regulation 1223/2009. Its use in cosmetics is only permitted under the specific conditions set out in the entry above, including applicable concentration limits, product type restrictions and required warning statements.

When including this substance in a formulation, all conditions — maximum concentration, product scope and warning labels — must be met simultaneously. Compliance with one condition does not override the others.

This record is linked to 1 CosIng inventory ingredient for name and identifier cross-reference. The page also surfaces 12 related annex records with overlapping identifiers, annex logic or naming patterns.

Compliance checklist

  • Document conditions of use in the Product Information File (PIF).

Frequently asked questions

Alpha-Terpinene is listed in Annex III of EU Regulation 1223/2009 as a restricted substance. It may only be used under the conditions specified in the entry, including any maximum concentration, product type limitation and required warning statements shown above.

CAS 99-86-5 is the unique numerical identifier assigned to Alpha-Terpinene by the Chemical Abstracts Service. In cosmetic compliance work, the CAS number is used to cross-reference the substance across regulatory databases, raw material specifications and safety assessment reports. Multiple EU annex entries may share the same CAS number if the same substance appears under different conditions or in different annexes.

Use the INCI Checker tool on this site to paste your full ingredient list (INCI) and scan it against all Annex II–VI entries. The tool highlights any ingredients that match restricted, prohibited or allergen-flagged records. This is useful for rapid compliance screening of finished product formulas or raw material declarations.
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Source note for Annex III record Alpha-Terpinene

This page summarizes one Annex III record for Alpha-Terpinene from public European Commission cosmetic materials and adds linked inventory or identifier matches when available.

Use this record page to review Annex III conditions for Alpha-Terpinene, but confirm any final regulatory decision against the current official annex wording and source files.

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