Compound record

Aluminum hydroxide

Also known as C 31C

21645-51-2 · mineral flame retardant · flame retardant

C 31C flame retardantmineral fillercables Hydrated aluminaAmphojelaluminum hydrate

Dossier Status Obligations Why Alternatives Changes Similar Sources

CAS 21645-51-2

Formula AlH3O3

Molecular weight 78.004 g/mol

InChIKey WNROFYMDJYEPJX-UHFFFAOYSA-K

Current EU status

Regulatory snapshot for Aluminum hydroxide

Aluminum hydroxide is currently surfaced as no current candidate list row imported in the EU.

The current imported view anchors this substance in CandidateList. The live rationale focuses on No positive Candidate List entry captured in the current imported source set, and this page is designed for fast status checks before deeper source review.

Searchers usually land here for the chemical name, CAS number, abbreviation C 31C, and the question of whether the substance is tied to SVHC, REACH, POPs, or SCIP-style compliance work.

No current Candidate List row importedcurrent statuslatest imported framework state

8 Mar 2026latest anchor datelisted, effective, or checked date

Identity

CAS, formula, aliases, and use context

CAS: 21645-51-2
EC: 244-492-7
Formula: AlH3O3
Molecular weight: 78.004 g/mol
Primary class: mineral flame retardant
Synonym count: 158

Search-friendly summary

Aluminum hydroxide (C 31C) , CAS 21645-51-2, is tracked here as a flame retardant substance in the mineral flame retardant class.

Common names and aliases

Hydrated aluminaAmphojelaluminum hydrateDried aluminium hydroxideAluminum hydroxide, driedALternaGEL

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

Use this when you want the timeline, not just the current state.

Sources

Verify where the data came from

Use this when you need to audit provenance before trusting a claim.

Action prompts

Fast compliance and screening routes

Article duties