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STEARETH-40

CAS 9005-00-9 (Generic)
81

Safety score · 0–100

Good

Derived from EU CosIng regulatory status, PubChem hazard data and published research. How we score.

About

Steareth-40 is a cosmetic ingredient used in product formulations. Exercise caution due to limited available safety data.

Steareth-40 is the polyethylene glycol 40-mole ether of stearyl alcohol (n-octadecanol). Listed in CosIng with emulsifying and surfactant functions and no EU restrictions. High EO degrees like EO40 provide excellent water solubility and reduce the lipophilic character of the C18 chain, making Steareth-40 suitable as a solubilizer and co-surfactant. The steareth series benefits from extensive safety data from CIR reviews. The primary impurity concern is 1,4-dioxane, which EU cosmetic GMP requires to be minimized. Steareth-40 is used at low concentrations (typically 0.1-5%) in emulsions and aqueous formulations.

Skin benefits

  • Effective solubilizer for fragrances and oil-soluble actives
  • Emulsifying agent for o/w systems
  • Provides smooth, non-greasy skin feel

Known concerns

  • 1,4-dioxane trace contamination possible
  • Mild eye irritation potential
  • May increase skin penetration of other formulation ingredients

References

EU

EU CosIng database

European Commission cosmetic ingredient registry — regulatory status, restrictions, authorised functions.

Related others

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This profile is for educational purposes and does not constitute medical advice. Regulatory status and scientific understanding evolve — always read the physical product label and consult a healthcare professional for personal concerns.