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CAS 1 record

CAS 99-86-5

CAS 99-86-5 matches 1 EU annex record across Annex II–VI of Regulation 1223/2009.

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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.

Records for CAS 99-86-5

1 total
Annex
III
Entry
131

Alpha-Terpinene

p-Mentha-1,3-diene

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 per…

EC
202-795-1

How CAS 99-86-5 is used on this site

CAS 99-86-5 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 1 EU annex record shares this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 99-86-5 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.

Frequently asked questions

A substance identified by CAS 99-86-5 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts. For example, a substance might be restricted under Annex III with specific conditions, and the same CAS might also appear in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

Cross-reference the CAS number against your raw material specification sheets and CoA documents. When a CAS appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met in your formulation. All annex entries sharing this CAS number are listed above.

A CAS number is assigned by the Chemical Abstracts Service (USA) and is globally recognised. An EC number is a European Commission identifier from inventories such as EINECS, ELINCS or the NLP list. Both identifiers may appear in EU cosmetic annex entries. Some substances have both, some have only one, and some older entries may have neither.

The INCI Checker accepts ingredient names, CAS numbers and EC numbers. Check this CAS number directly, then verify the result against supplier specification sheets and every linked annex condition.
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