Why does CAS 16949-65-8 appear in more than one EU cosmetic annex?

A substance identified by CAS 16949-65-8 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts — for example, restricted under Annex III with specific conditions, while also appearing in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

How do I check if my formula contains a substance with CAS 16949-65-8?

Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 16949-65-8 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 16949-65-8

Q: How do I use CAS 16949-65-8 for compliance screening?

Cross-reference CAS 16949-65-8 against your raw material specification sheets and CoA documents. When it appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met. All annex entries sharing this CAS number are listed on this page.

CAS 16949-65-8 matches 1 EU annex record across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 16949-65-8

CAS 16949-65-8PubChem CID 61861

Magnesium hexafluorosilicate

Magnesium fluorosilicate is a crystalline solid. Decomposes at 120 °C. Contact may cause slight irritation to skin, eyes, and mucous membranes. May be slightly toxic by ingestion. Used to make other chemicals. — CAMEO Chemicals

IUPAC name: magnesium hexafluorosilicon(2-)

Molecular formula: F6MgSi
Molecular weight: 166.38 g/mol
Exact mass: 165.9523872 Da
Topological polar surface area: 0.0 Å²
Hydrogen-bond donors: 0
Hydrogen-bond acceptors: 7
Covalent units: 2
Defined stereocentres: 0

Also known as

Magnesium fluorosilicateCaswell No. 532Hexafluorosilicate(2-) magnesium (1:1)Fluosilicate de magnesium [French]Fluosilicate de magnesiumSilicate(2-), hexafluoro-, magnesium (1:1)EINECS 241-022-2UN2853

16 more reported names

EPA Pesticide Chemical Code 075304UNII-H37V80D2JSMAGNESIUM HEXAFLUOROSILICATE [MI]EC 241-022-2MAGNESIUM SILICOFLUORIDE, (SOLID)MAGNESIUM SILICOFLUORIDE, [SOLID]RefChem:155211Magnesium hexafluorosilicate(2)FLUOROSILICATO DE MAGNESIOhexafluorosilicate, magnesium saltSILICO FLUORURO DE MAGNESIOSilicate(2-), hexafluoro-, magnesiumMAGNESIUM FLUOROSILICATE [INCI]Hexafluorosilicate(2) magnesium (1:1)241-022-2Silicate(2), hexafluoro, magnesium (1:1)

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

EPA DTXSID:DTXSID70884950

Retrieved from NIH PubChem on 2026-09-02 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 16949-65-8

1 total

Annex

III

Entry

MAGNESIUM FLUOROSILICATE

Magnesium Fluorosilicate

Contains magnesium fluorosilicate For any toothpaste with compounds containing fluorine in a concentration of 0.1 to 0.15% calculated as F unless it is already labelled as contra-indicated for children (e.g. "for adult…

241-022-2

Max concentration

How CAS 16949-65-8 is used on this site

CAS 16949-65-8 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 1 EU annex record shares this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 16949-65-8 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.

Frequently asked questions

A substance identified by CAS 16949-65-8 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts. For example, a substance might be restricted under Annex III with specific conditions, and the same CAS might also appear in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

Cross-reference the CAS number against your raw material specification sheets and CoA documents. When a CAS appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met in your formulation. All annex entries sharing this CAS number are listed above.

A CAS number is assigned by the Chemical Abstracts Service (USA) and is globally recognised. An EC number is a European Commission identifier from inventories such as EINECS, ELINCS or the NLP list. Both identifiers may appear in EU cosmetic annex entries. Some substances have both, some have only one, and some older entries may have neither.

The INCI Checker accepts ingredient names, CAS numbers and EC numbers. Check this CAS number directly, then verify the result against supplier specification sheets and every linked annex condition.

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