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Annex II Entry 1553 CMR30/07/2020

Di-tert-butyl peroxide

Di-tert-butyl peroxide 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: 1553
CMR

Record details

Chemical name

Di-tert-butyl peroxide

Chemical / IUPAC name

Di-tert-butyl peroxide

Regulatory information

Regulation

(EU) 2019/831

CMR

CategoryCarcinogenicMutagenicReprotoxic
Cat. 2—✓—

Key data

CAS
110-05-4
EC
203-733-6
Annex
II
Entry number
1553

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

Annex II 1547
Nearby record in the same annex

Tetrahydrofuran

CAS: 109-99-9
EC: 203-726-8

What Annex II means for Di-tert-butyl peroxide

Di-tert-butyl peroxide 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).
  • This substance has CMR classification. Review the CMR table above and verify current Annex II/III status before use.

Frequently asked questions

Yes. Di-tert-butyl peroxide 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 110-05-4 is the unique numerical identifier assigned to Di-tert-butyl peroxide 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.

Di-tert-butyl peroxide 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 Di-tert-butyl peroxide

This page summarizes one Annex II record for Di-tert-butyl peroxide 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 Di-tert-butyl peroxide, but confirm any final regulatory decision against the current official annex wording and source files.

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