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Annex II Entry 9 17/10/2010

Thyropropic acid (INN) and its salts

Thyropropic acid (INN) and its salts 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: 9

Record details

Chemical name

Thyropropic acid (INN) and its salts

Chemical / IUPAC name

4-(4-Hydroxy-3-iodophenoxy)-3,5-diiodobenzenepropanoic acid

Regulatory information

Regulation

(EC) 2009/1223

Key data

CAS
51-26-3
EC
—
Annex
II
Entry number
9

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

What Annex II means for Thyropropic acid (INN) and its salts

Thyropropic acid (INN) and its salts is listed as a prohibited substance under Annex II of EU Cosmetics Regulation 1223/2009. No concentration limit applies — the presence of this substance in any cosmetic product placed on the EU market is not permitted regardless of use level.

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. Thyropropic acid (INN) and its salts is listed in Annex II of EU Cosmetics Regulation 1223/2009 as a prohibited substance. It must not be present in any cosmetic product placed on the EU market at any concentration.

CAS 51-26-3 is the unique numerical identifier assigned to Thyropropic acid (INN) and its salts 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 Thyropropic acid (INN) and its salts

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

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