Why does CAS 75-21-8 appear in more than one EU cosmetic annex?

A substance identified by CAS 75-21-8 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts — for example, restricted under Annex III with specific conditions, while also appearing in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

How do I check if my formula contains a substance with CAS 75-21-8?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 75-21-8 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 75-21-8

Q: How do I use CAS 75-21-8 for compliance screening?

Cross-reference CAS 75-21-8 against your raw material specification sheets and CoA documents. When it appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met. All annex entries sharing this CAS number are listed on this page.

CAS 75-21-8 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 75-21-8

CAS 75-21-8PubChem CID 6354

Ethylene Oxide

Ethylene oxide appears as a clear colorless gas with an ethereal odor with a flash point below 0 °F. Liquid less dense than water. Vapors heavier than air. May polymerize exothermically if heated or contaminated. If the polymerization takes place inside a container, the container may rupture violently. Vapors very toxic. Vapors irritate the eyes, skin, and respiratory system. Prolonged skin contact may result in delayed burns. Used to make other chemicals, as a fumigant and industrial sterilant. — CAMEO Chemicals

IUPAC name: oxirane

Molecular formula: C2H4O
Molecular weight: 44.05 g/mol
Exact mass: 44.026214747 Da
XLogP3: -0.1
Topological polar surface area: 12.5 Å²
Hydrogen-bond donors: 0
Hydrogen-bond acceptors: 1
Covalent units: 1
Defined stereocentres: 0

Also known as

Epoxyethane1,2-EpoxyethaneOxacyclopropaneDihydrooxireneAnproleneOxidoethaneOxyfumeEthene oxide

16 more reported names

Dimethylene oxideAmproleneAnprolineAethylenoxidMerpolOxiran1,2-EpoxyaethanOxyfume 12T-GasOxirene, Dihydro-EthyleenoxideOxiraanEthoxEtylenu tlenekFEMA No. 2433Rcra waste number U115

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:27561
ChEMBL:CHEMBL1743219
EPA DTXSID:DTXSID0020600
PubMed:39068997
PubMed:24029818
PubMed:23082678
PubMed:23063518
PubMed:23062436
PubMed:23013195
PubMed:22988984
PubMed:22987140
PubMed:22982165
PubMed:22971978
PubMed:22953195
PubMed:22953181

Retrieved from NIH PubChem on 2026-09-02 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 75-21-8

1 total

Annex

Entry

182

Ethylene oxide

200-849-9

CMR

How CAS 75-21-8 is used on this site

CAS 75-21-8 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 75-21-8 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 75-21-8 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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