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Annex II Entry 190 15/10/2010

Fluorouracil (INN)

Fluorouracil (INN) 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: 190

Chemical identity and properties

PubChem 2D chemical structure for CAS 51-21-8
CAS 51-21-8PubChem CID 3385

5-Fluorouracil

5-fluorouracil is a nucleobase analogue that is uracil in which the hydrogen at position 5 is replaced by fluorine. It is an antineoplastic agent which acts as an antimetabolite - following conversion to the active deoxynucleotide, it inhibits DNA synthesis (by blocking the conversion of deoxyuridylic acid to thymidylic acid by the cellular enzyme thymidylate synthetase) and so slows tumour growth. It has a role as a radiosensitizing agent, an antimetabolite, an antineoplastic agent, a xenobiotic, an immunosuppressive agent and an environmental contaminant. It is an organofluorine compound and a nucleobase analogue. It is functionally related to a uracil. — ChEBI

IUPAC name
5-fluoro-1H-pyrimidine-2,4-dione
Molecular formula
C4H3FN2O2
Molecular weight
130.08 g/mol
Exact mass
130.01785550 Da
XLogP3
-0.9
Topological polar surface area
58.2 Ų
Hydrogen-bond donors
2
Hydrogen-bond acceptors
3
Covalent units
1
Defined stereocentres
0

Also known as

fluorouracilEfudexFluracilFluoroblastinCarzonalQueroplexFlurilPhthoruracil
16 more reported names
ArumelTimazinFluracilumUlup5-FluoracilFluorouracilumFluro Uracil5 Fluorouracil5-Fluoruracil5-Fluoro-2,4(1H,3H)-pyrimidinedioneFluorouraciloFtoruracilEfurixEffluderm (free base)Fluroblastin5-Fluoropyrimidine-2,4-dione
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Record details

Chemical name

Fluorouracil (INN)

Chemical / IUPAC name

2,4(1H,3H)-Pyrimidinedione, 5-fluoro-

Regulatory information

Regulation

(EC) 2009/1223

See every entry this act set

Key data

CAS
51-21-8
EC
200-085-6
Annex
II
Entry number
190

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

Annex II 189
Nearby record in the same annex

Fluoresone (INN)

CAS: 2924-67-6
EC: 220-889-0
Annex II 187
Nearby record in the same annex

Fluanisone (INN)

CAS: 1480-19-9
EC: 216-038-8

What Annex II means for Fluorouracil (INN)

Fluorouracil (INN) 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).

Frequently asked questions

Yes. Fluorouracil (INN) 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 51-21-8 is the unique numerical identifier assigned to Fluorouracil (INN) 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.

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 Fluorouracil (INN)

This page summarizes one Annex II record for Fluorouracil (INN) 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 Fluorouracil (INN), but confirm any final regulatory decision against the current official annex wording and source files.

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