Skip to main content
CosIng Checker
CosIng Checker
EU cosmetic ingredients, restrictions and safety
Login
Annex II Entry 1741 18/06/2025

dibutyltin oxide

dibutyltin oxide is listed in Annex II as a prohibited substance for cosmetic products placed on the EU market.

Search similar Back to annex Compare
Prohibited substance— Annex II, EU Regulation 1223/2009
Entry: 1741

Chemical identity and properties

PubChem 2D chemical structure for CAS 818-08-6
CAS 818-08-6PubChem CID 61221

Dibutyltin oxide

Dibutyltin oxide is an organotin compound. It is used mainly in organic synthesis. Tin is a chemical element with the symbol Sn and atomic number 50. It is a natural component of the earth's crust and is obtained chiefly from the mineral cassiterite, where it occurs as tin dioxide. (L307, L309, L312) — Toxin and Toxin Target Database (T3DB)

IUPAC name
dibutyl(oxo)tin
Molecular formula
C8H18OSn
Molecular weight
248.94 g/mol
Exact mass
250.037968 Da
Topological polar surface area
17.1 Ų
Hydrogen-bond donors
0
Hydrogen-bond acceptors
1
Covalent units
1
Defined stereocentres
0

Also known as

DibutyloxotinDibutyloxostannaneStannane, dibutyloxo-Dibutylstannane oxidedibutylstannanoneDibutyloxide of tinDibutylstannium oxideTin, dibutyl-, oxide
16 more reported names
T435H74FO0NSC-28130RefChem:132969212-449-1Dibutyltin(IV) oxideDI-N-BUTYLTIN OXIDETin, dibutyloxo-Di-n-butyl-zinn-oxydKyslicnik di-n-butylcinicityDBOTDibutyltinoxideStannane, dibutyloxo-;Di-n-butyl-zinn-oxyd [German]EINECS 212-449-1Kyslicnik di-n-butylcinicity [Czech]NSC 28130
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

dibutyltin oxide

Regulatory information

Regulation

(EU) 2025/877

See every entry this act set

Key data

CAS
818-08-6
EC
212-449-1
Annex
II
Entry number
1741

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

What Annex II means for dibutyltin oxide

dibutyltin oxide 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. dibutyltin oxide 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 818-08-6 is the unique numerical identifier assigned to dibutyltin oxide 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.
Open INCI Checker

Source note for Annex II record dibutyltin oxide

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

View sourcesView updates

Tools & next steps

Check your formula

Paste a full INCI list to detect dibutyltin oxide and other flagged EU annex records in one pass.

INCI Checker

Compare entries

Compare dibutyltin oxide side by side with another annex record to review differences in restrictions, concentrations and annex placement.

Compare

Browse the annex

See all records in Annex II and compare regulatory conditions across substances in this annex.

Open Annex II