Common Name(s): Oleth-7,oleth-7,peg-7 oleyl ether,oleyl alcohol ethoxylate 7eo

CAS Number: 9004-98-2

DESCRIPTION

What It Does: Stabilizes oil-in-water emulsions while conditioning the skin. the oleyl (olive-like) lipid tail stays liquid at skin temperature, giving a smooth, non-waxy feel.

Why It's Used: Oleth-7 is selected for hlb ~10 balanced o/w emulsification from 7-eo ethoxylation of c18:1 oleyl alcohol — the cis-9 double bond in the oleyl tail prevents crystallization at skin temperature, providing a fluid, non-waxy skin feel that is absent from saturated alkyl ethoxylate emulsifiers at equivalent hlb.

How It Works: 7-eo chain → hydrophilic water binding; oleyl c18:1 cis tail → oil phase anchoring; cis-double bond → liquid at room temperature → non-waxy skin feel; hlb ~10 → o/w emulsion interface stabilization.

Typically Found In: Moisturizers,emulsions,cleansers

TECHNICAL DETAILS

Primary Category: Functional ingredient – emulsifier

Secondary Functions: Skin conditioning,solubilizing

Application Areas:

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: Oleyl alcohol from plant (olive, rapeseed) or marine source; eo from petrochemical. [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; oleyl-related

Sensitivity Concerns: Generally well tolerated. ethoxylate residuals may cause mild sensitivity in highly reactive individuals.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile. ewg score: 1–2.

Works Well With: Emollients,humectants,fatty alcohols

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Oleyl-derived ethoxylates remain characteristically liquid at room temperature — the cis-9 double bond kink prevents crystalline packing that causes waxy residue in saturated alkyl ethoxylates (ceteth, steareth series) at equivalent eo chain length.

Last Verified: 2026-03-27

Primary Sources: Cosing database,oleth-7 peg emulsifier review