Methylbutenes

INCI: METHYLBUTENES

CAS Number
513-35-9 (2-methyl-2-butene) / mixture of methylbutene isomers
Function
Solvent / viscosity controlling
Safety Rating
MODERATE

Regulatory Status

🇪🇺 EU Status permitted
🇺🇸 US Status permitted
US Notes Permitted — no specific cosmetic CFR restriction

For full compliance data across 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
not established
Dermal Absorption
negligible
Sensitization
low

Calculate MoS for your specific formulation with the MoS Calculator.

Expert Verdict

Volatile hydrocarbon with inhalation exposure concern in spray products; flammable (flash point < 0°C) with limited cosmetic-specific safety data requiring concentration limits and manufacturing ventilation controls.

⚠️
Concern Level: Moderate

Frequently Asked Questions

Is Methylbutenes safe in cosmetics?

Volatile hydrocarbon with inhalation exposure concern in spray products; flammable (flash point < 0°C) with limited cosmetic-specific safety data requiring concentration limits and manufacturing ventilation controls. The EU classifies Methylbutenes as "permitted". Safety rating: MODERATE.

Is Methylbutenes allowed in the EU?

Methylbutenes EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.

What does Methylbutenes do in cosmetics?

Methylbutenes functions as: Solvent / viscosity controlling. It is classified as a cosmetic ingredient in our database. CAS number: 513-35-9 (2-methyl-2-butene) / mixture of methylbutene isomers.

What is the Margin of Safety for Methylbutenes?

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.

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