Why does CAS 311-45-5 appear in more than one EU cosmetic annex?

A substance identified by CAS 311-45-5 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 311-45-5?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 311-45-5 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 311-45-5

Q: How do I use CAS 311-45-5 for compliance screening?

Cross-reference CAS 311-45-5 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 311-45-5 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 311-45-5

CAS 311-45-5PubChem CID 9395

Paraoxon

Paraoxon is an aryl dialkyl phosphate where both the alkyl groups are ethyl and the aryl group is 4-nitrophenyl. It has a role as an EC 3.1.1.7 (acetylcholinesterase) inhibitor and a mouse metabolite. It is an organophosphate insecticide and an aryl dialkyl phosphate. — ChEBI

IUPAC name: diethyl (4-nitrophenyl) phosphate

Molecular formula: C10H14NO6P
Molecular weight: 275.19 g/mol
Exact mass: 275.05587416 Da
XLogP3: 2.0
Topological polar surface area: 90.6 Å²
Hydrogen-bond donors: 0
Hydrogen-bond acceptors: 6
Covalent units: 1
Defined stereocentres: 0

Also known as

PhosphacolDiethyl paraoxonMiotisalEthyl paraoxonDiethyl 4-nitrophenyl phosphateMintacolDiethyl p-nitrophenyl phosphatePhosphachole

16 more reported names

FosfakolOxyparathionChinortoPhosphakolEticolChinortaParaoxoneSoluglaucitMintacoParoxanMiotisal APhosphoric acid, diethyl 4-nitrophenyl esterEster 25DiethylparaoxonSoluglacitPestox 101

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:27827
ChEMBL:CHEMBL23838
EPA DTXSID:DTXSID6024046
PubMed:40902968
PubMed:40419014
PubMed:35151785
PubMed:34778934
PubMed:34506764
PubMed:34147486
PubMed:33720374
PubMed:33592259
PubMed:33517499
PubMed:33497710
PubMed:33176172
PubMed:31872761

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 311-45-5

1 total

Annex

Entry

170

Diethyl 4-nitrophenyl phosphate (Paraoxon - ISO)

206-221-0

How CAS 311-45-5 is used on this site

CAS 311-45-5 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 311-45-5 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 311-45-5 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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