Compound record

Octamethylcyclotetrasiloxane

Also known as OMCTS

556-67-2 · candidate list substance / siloxane · cosmetics

OMCTS SVHC Candidate ListEU monitoringcosmeticsformulation OCTAMETHYLCYCLOTETRASILOXANECyclotetrasiloxane, octamethyl-2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane

Dossier Status Obligations Why Alternatives Changes Similar Sources

CAS 556-67-2

Formula C8H24O4Si4

Molecular weight 296.61 g/mol

InChIKey HMMGMWAXVFQUOA-UHFFFAOYSA-N

Current EU status

Regulatory snapshot for Octamethylcyclotetrasiloxane

Octamethylcyclotetrasiloxane 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) vPvB (Article 57e), and this page is designed for fast status checks before deeper source review.

Searchers usually land here for the chemical name, CAS number, abbreviation OMCTS, 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

27 Jun 2018latest anchor datelisted, effective, or checked date

Identity

CAS, formula, aliases, and use context

CAS: 556-67-2
EC: 209-136-7
Formula: C8H24O4Si4
Molecular weight: 296.61 g/mol
Primary class: candidate list substance
Synonym count: 82

Search-friendly summary

Octamethylcyclotetrasiloxane (OMCTS) , CAS 556-67-2, is tracked here as a cosmetics substance in the candidate list substance class.

Common names and aliases

OCTAMETHYLCYCLOTETRASILOXANECyclotetrasiloxane, octamethyl-2,2,4,4,6,6,8,8-Octamethyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocaneOktamethylcyklotetrasiloxanCyclic dimethylsiloxane tetramerCyclomethicone 4

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

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Why monitored

Why this substance is monitored in the EU

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Alternatives

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Changes

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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

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Source check

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