Compound record

Bis(tributyltin) oxide (TBTO)

Also known as HBD

56-35-9 · candidate list substance

HBD SVHC Candidate ListEU monitoring Tributyltin oxideBIS(TRIBUTYLTIN) OXIDEHexabutyldistannoxane

Dossier Status Obligations Why Alternatives Changes Similar Sources

CAS 56-35-9

Formula C24H54OSn2

Molecular weight 596.1 g/mol

InChIKey APQHKWPGGHMYKJ-UHFFFAOYSA-N

Current EU status

Regulatory snapshot for Bis(tributyltin) oxide (TBTO)

Bis(tributyltin) oxide (TBTO) is currently surfaced as candidate list substance in the EU.

The current imported view anchors this substance in CandidateList. The live rationale focuses on PBT (Article 57d), and this page is designed for fast status checks before deeper source review.

Searchers usually land here for the chemical name, CAS number, abbreviation HBD, and the question of whether the substance is tied to SVHC, REACH, POPs, or SCIP-style compliance work.

Candidate List substancecurrent statuslatest imported framework state

28 Oct 2008latest anchor datelisted, effective, or checked date

Identity

CAS, formula, aliases, and use context

CAS: 56-35-9
EC: 200-268-0
Formula: C24H54OSn2
Molecular weight: 596.1 g/mol
Primary class: candidate list substance
Synonym count: 158

Search-friendly summary

Bis(tributyltin) oxide (TBTO) (HBD) , CAS 56-35-9, is tracked here as a monitored substance in the candidate list substance class.

Common names and aliases

Tributyltin oxideBIS(TRIBUTYLTIN) OXIDEHexabutyldistannoxaneBis(tributyltin)oxideButinoxDistannoxane, hexabutyl-

What to do next

Use the right route for status, SCIP, and source questions

Status

Current legal state, Candidate List signals, and source-backed rationale

Go here for the framework answer block, listed dates, reasons, and the imported basis for the current EU status.

Obligations

Who needs to act, what to check, and whether SCIP matters

Use this when the question is operational: SCIP, article communication, threshold review, portfolio screening, or substitute work.

Why monitored

Why this substance is monitored in the EU

Use this when you want the hazard or legal basis behind the current status, not just the status label itself.

Alternatives

Potential substitutes and nearby molecules

Use this to branch into lower-pressure neighbors, same-class analogs, and candidate-list peers.

Changes

What changed over time

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Sources

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Action prompts

Fast compliance and screening routes

Article duties

Check Candidate List threshold and SCIP relevance

Use this when the substance may sit in articles, components, or imported goods and you need to confirm communication and SCIP workflows.

Source check

Verify the legal source before repeating the claim

Every summary should point back to the underlying authority surface. Use the source route when the exact notice, registry entry, or legal text matters.