Why does CAS 542-88-1 appear in more than one EU cosmetic annex?

A substance identified by CAS 542-88-1 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 542-88-1?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 542-88-1 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 542-88-1

Q: How do I use CAS 542-88-1 for compliance screening?

Cross-reference CAS 542-88-1 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 542-88-1 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 542-88-1

CAS 542-88-1PubChem CID 10967

Bis(Chloromethyl) Ether

Bis(chloromethyl) ether is a clear liquid with a strong unpleasant odor. It does not occur naturally. It dissolves easily in water, but degrades rapidly and readily evaporates into air. In the past, it was used to make several types of polymers, resins, and textiles, but its use is now highly restricted. Only small quantities of bis(chloromethyl) ether are produced in the United States. The small quantities that are produced are only used in enclosed systems to make other chemicals. However, small quantities of bis(chloromethyl) ether may be formed as an impurity during the production of another chemical, chloromethyl methyl ether. — Agency for Toxic Substances and Disease Registry (ATSDR)

IUPAC name: chloro(chloromethoxy)methane

Molecular formula: C2H4Cl2O
Molecular weight: 114.96 g/mol
Exact mass: 113.9639201 Da
XLogP3: 1.5
Topological polar surface area: 9.2 Å²
Hydrogen-bond donors: 0
Hydrogen-bond acceptors: 1
Covalent units: 1
Defined stereocentres: 0

Also known as

Bis(chloromethyl)etherChloromethyl ethersym-Dichloromethyl etherMethane, oxybis[chloro-Oxybis(chloromethane)Dichloromethyl etherEther, bis(chloromethyl)Dichlorodimethyl ether

16 more reported names

Monochloromethyl Ethersym-Dichloro-dimethyl etherDichlordimethylaetherBis-CMEOxybis[chloromethane]RCRA waste number P0161,1'-Dichlorodimethyl etherDimethyl-1,1'-dichloroetherMethane, oxybis(chloro-Dichloromethyl ether, symmetricalCCRIS 90alpha,alpha'-Dichlorodimethyl etherBRN 1679223CHEBI:82270Ether, ChloromethylEther, Dichloromethyl

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:82270
ChEMBL:CHEMBL3185875
EPA DTXSID:DTXSID8020173
PubMed:21850114
PubMed:21089828
PubMed:17036113
PubMed:16818262
PubMed:15531427
PubMed:15320321
PubMed:12948880
PubMed:12082370
PubMed:4038687

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 542-88-1

1 total

Annex

Entry

667

Oxybis[chloromethane]; bis (Chloromethyl) ether

208-832-8

CMR

How CAS 542-88-1 is used on this site

CAS 542-88-1 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 542-88-1 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 542-88-1 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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