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Annex II Entry 1072 CMR17/12/2010

Fenthion (ISO)

Fenthion (ISO) is listed in Annex II as a prohibited substance for cosmetic products placed on the EU market.

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Prohibited substance— Annex II, EU Regulation 1223/2009
Entry: 1072
CMR

Chemical identity and properties

PubChem 2D chemical structure for CAS 55-38-9
CAS 55-38-9PubChem CID 3346

Fenthion

Fenthion is an organic thiophosphate that is O,O-dimethyl hydrogen phosphorothioate in which the hydrogen atom of the hydroxy group is replaced by a 3-methyl-4-(methylsulfanyl)phenyl group. It exhibits acaricidal and insecticidal activities. It has a role as an acaricide, an insecticide, an agrochemical, an avicide, an EC 3.1.1.8 (cholinesterase) inhibitor and an EC 3.1.1.7 (acetylcholinesterase) inhibitor. It is functionally related to a 4-(methylsulfanyl)-m-cresol. — ChEBI

IUPAC name
dimethoxy-(3-methyl-4-methylsulfanylphenoxy)-sulfanylidene-lambda5-phosphane
Molecular formula
C10H15O3PS2
Molecular weight
278.3 g/mol
Exact mass
278.02002368 Da
XLogP3
4.1
Topological polar surface area
85.1 Ų
Hydrogen-bond donors
0
Hydrogen-bond acceptors
5
Covalent units
1
Defined stereocentres
0

Also known as

LebaycidSpottonBaytexQueletoxBaycidTiguvonEntexFenthione
16 more reported names
PhenthionFiguronTalodexSulfidophosFenthion-methylBayer 29493Pro-SpotFenthion 4EMPP (pesticide)Bay-BassaBayer 9007Bayer S-1752OMS 24-Methylmercapto-3-methylphenyl dimethyl thiophosphateNCI-C08651BAY 29493
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

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

Record details

Chemical name

Fenthion (ISO)

Chemical / IUPAC name

O,O-dimethyl-o-(4-methylthion-m-tolyl)phosphorothioate

Regulatory information

Regulation

(EC) 2009/1223

See every entry this act set

Other directives

(EC) 2009/790

SCCS opinions

CMR

CategoryCarcinogenicMutagenicReprotoxic
Cat. 2—✓—

Key data

CAS
55-38-9
EC
200-231-9
Annex
II
Entry number
1072

Direct matches are limited for this record, so nearby entries from Annex II are shown as well.

Annex II 1073
Nearby record in the same annex

Chlordane, pur

CAS: 57-74-9
EC: 200-349-0
Annex II 1075
Nearby record in the same annex

Fenarimol (ISO)

CAS: 60168-88-9
EC: 262-095-7
Annex II 1068
Nearby record in the same annex

DNOC (ISO)

CAS: 534-52-1
EC: 208-601-1
Annex II 1076
Nearby record in the same annex

Acetamide

CAS: 60-35-5
EC: 200-473-5
Annex II 1078
Nearby record in the same annex

Dieldrin (ISO)

CAS: 60-57-1
EC: 200-484-5

What Annex II means for Fenthion (ISO)

Fenthion (ISO) is listed as a prohibited substance under Annex II of EU Cosmetics Regulation 1223/2009 and must not be intentionally added. Article 17 separately addresses unintended small quantities that are technically unavoidable under good manufacturing practice and compatible with the Article 3 safety requirement.

Formulators must screen their ingredients and raw materials to ensure none contain this substance. Suppliers should provide documentation confirming absence when requested.

The page also surfaces 12 related annex records with overlapping identifiers, annex logic or naming patterns.

Compliance checklist

  • Verify this substance is absent from all raw materials and finished formulations.
  • Request absence confirmation or CoA from raw material suppliers.
  • Document the screening result in the Product Information File (PIF).
  • This substance has CMR classification. Review the CMR table above and verify current Annex II/III status before use.

Frequently asked questions

Yes. Fenthion (ISO) is listed in Annex II of EU Cosmetics Regulation 1223/2009 and is prohibited as an intentionally added cosmetic ingredient. Article 17 provides a narrow exception for unintended small quantities that are technically unavoidable under good manufacturing practice, provided the product remains safe under Article 3.

CAS 55-38-9 is the unique numerical identifier assigned to Fenthion (ISO) by the Chemical Abstracts Service. In cosmetic compliance work, the CAS number is used to cross-reference the substance across regulatory databases, raw material specifications and safety assessment reports. Multiple EU annex entries may share the same CAS number if the same substance appears under different conditions or in different annexes.

Fenthion (ISO) has a CMR (carcinogenic, mutagenic or reprotoxic) classification under EU CLP Regulation. Under Article 15 of EU Cosmetics Regulation 1223/2009, CMR substances of category 1A or 1B are prohibited in cosmetics unless specifically permitted. Category 2 CMR substances may be used only if assessed safe by the SCCS. Always verify current annex status and any applicable derogations before use.

Use the INCI Checker tool on this site to paste your full ingredient list (INCI) and scan it against all Annex II–VI entries. The tool highlights any ingredients that match restricted, prohibited or allergen-flagged records. This is useful for rapid compliance screening of finished product formulas or raw material declarations.
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Source note for Annex II record Fenthion (ISO)

This page summarizes one Annex II record for Fenthion (ISO) from public European Commission cosmetic materials and adds linked inventory or identifier matches when available.

Use this record page to review Annex II conditions for Fenthion (ISO), but confirm any final regulatory decision against the current official annex wording and source files.

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