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Common Name(s): Laureth-9,peg-9 lauryl ether,peg-9 dodecanol ether
CAS Number: 3055-99-0
DESCRIPTION
What It Does: Helps oil and water blend and can dissolve oily ingredients into water-based products.
Why It's Used: Hlb ~13 makes laureth-9 suitable for o/w emulsification and oil solubilization; widely used in cleansers and emulsions.
How It Works: 9 eo units give hlb ~13; c12 lauryl chain provides detergent activity; suitable for clear-phase oil solubilization and light o/w emulsification.
Typically Found In: Cleansers,o/w emulsions,oil solubilizers,toners
TECHNICAL DETAILS
Primary Category: Functional ingredient – emulsifier
Secondary Functions: Solubilizing,surfactant,cleansing
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: 0.5%–5%
SOURCING & ETHICS
Vegan Status: Conditional - feedstock declaration required
Halal Status: Unverified - feedstock declaration required (plant, animal and petrochemical routes all exist)
Source Notes: Lauryl alcohol from coconut; eo from petrochemical; semi-natural. [audit 2026-07-29 rev2: origin-dependent: the same inci exists in plant, animal and petrochemical versions and the name does not discriminate. determination requires shariah-panel sign-off.]
SKIN COMPATIBILITY
Irritancy Rating: 1/5 – very low
Comedogenicity Rating: 1/5 – low
Sensitivity Concerns: Well tolerated. cir reviewed: safe as used.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Good safety profile. ewg score: 1–2.
Works Well With: Anionic surfactants,amphoteric surfactants,humectants
Avoid Combining With: No significant incompatibilities
SCIENTIFIC NOTE
Laureth-9 (hlb ~13) is near the optimal hlb range for both emulsification and solubilization of vegetable oils; cas 3055-99-0 refers to the mixed-eo homologue distribution centered around 9 eo units.
Last Verified: 2026-03-27
Primary Sources: Cosing database,inci dictionary,cir safety assessment lauryl ethoxylates