Regulatory Status
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Safety Data
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Expert Verdict
Methoxy groups hydrolyze to release methanol in trace quantities; the thiol group is a potential sensitizer at high concentrations; as a surface treatment residual on pigments, exposure levels are typically negligible.. Organosilane with a reactive mercapto (-SH) group and three hydrolyzable methoxy groups; creates covalent bonds between organic polymers and mineral substrates (e.g., TiO₂, mica, iron oxides).
Regulatory Flags
Frequently Asked Questions
Is Mercaptopropyltrimethoxysilane safe in cosmetics?
Methoxy groups hydrolyze to release methanol in trace quantities; the thiol group is a potential sensitizer at high concentrations; as a surface treatment residual on pigments, exposure levels are typically negligible.. Organosilane with a reactive mercapto (-SH) group and three hydrolyzable methoxy groups; creates covalent bonds between organic polymers and mineral substrates (e.g., TiO₂, mica, iron oxides). The EU classifies Mercaptopropyltrimethoxysilane as "prohibited". Safety rating: MODERATE.
Is Mercaptopropyltrimethoxysilane allowed in the EU?
Mercaptopropyltrimethoxysilane EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.
What does Mercaptopropyltrimethoxysilane do in cosmetics?
Mercaptopropyltrimethoxysilane functions as: Surface modifier / binding agent - a silane coupling agent that bonds organic materials to inorganic surfaces. In cosmetics, used for surface treatment of pigments and fillers to improve dispersibility and skin adhesion.. It is classified as a cosmetic ingredient in our database. CAS number: 4420-74-0.
What is the Margin of Safety for Mercaptopropyltrimethoxysilane?
not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.
Compliance Tools
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Related Ingredients
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