Why does CAS 34123-59-6 appear in more than one EU cosmetic annex?

A substance identified by CAS 34123-59-6 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.

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Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 34123-59-6 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 34123-59-6

Q: How do I use CAS 34123-59-6 for compliance screening?

Cross-reference CAS 34123-59-6 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 34123-59-6 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 34123-59-6

CAS 34123-59-6PubChem CID 36679

Isoproturon

Isoproturon is a member of the class of phenylureas that is 1,1-dimethylurea substituted by a p-cumenyl group at position 3. A selective, systemic herbicide used to control annual grasses and broadleaf weeds in cereals, its use within the EU has been banned after September 2017 on the grounds of potential groundwater contamination and risks to aquatic life; there have also been concerns about its endocrine-disrupting properties. It has a role as a herbicide, an agrochemical, a xenobiotic and an environmental contaminant. — ChEBI

IUPAC name: 1,1-dimethyl-3-(4-propan-2-ylphenyl)urea

Molecular formula: C12H18N2O
Molecular weight: 206.28 g/mol
Exact mass: 206.141913202 Da
XLogP3: 2.9
Topological polar surface area: 32.3 Å²
Hydrogen-bond donors: 1
Hydrogen-bond acceptors: 1
Covalent units: 1
Defined stereocentres: 0

Also known as

GraminonTolkan3-(4-Isopropylphenyl)-1,1-dimethylureaArelonBelgranArelon RNocilonIPU Stefes

16 more reported names

IP-FloHytane 500LZodiac TXDPX 67743-p-Cumenyl-1,1-dimethylureaCGA-18731HOE 16410N-4-Isopropylphenyl-N,N-dimethylureaIP 50CL 12150Urea, 3-p-cumenyl-1,1-dimethyl-N,N-Dimethyl-N'-(4-(1-methylethyl)phenyl)ureaN-(4-Isopropylphenyl)-N',N'-dimethylharnstoff3-(4-isopropylphenyl)-1,1-dimethyl-ureaCHEBI:6049N-(Isopropyl-4-phenyl)-N',N'-dimethyluree

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:6049
ChEMBL:CHEMBL2251591
EPA DTXSID:DTXSID1042077
PubMed:26313537
PubMed:23000746
PubMed:22952981
PubMed:22938719
PubMed:22771356
PubMed:22750170
PubMed:22634058
PubMed:22627152
PubMed:22578198
PubMed:22574059
PubMed:22573957
PubMed:22560026

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 34123-59-6

1 total

Annex

Entry

1061

3-(4-Isopropylphenyl)-1,1-dimethylurea (Isoproturon - ISO)

251-835-4

CMR

How CAS 34123-59-6 is used on this site

CAS 34123-59-6 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 34123-59-6 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 34123-59-6 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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