Oleth-5
AKA “Oleyl Ethoxylate 5, Oleth 5, Polyethylene Glycol Monooleyl Ether”
Synthetic
Ingredient Facts
Oleth-5
AKA: Oleyl Ethoxylate 5, Oleth 5, Polyethylene Glycol Monooleyl Ether
Synthetic · Cleansing · EWG: 4
Synthetic
Cleanser
Emulsifier
Synthetic
Clean
Helps blend oil and water-based ingredients together, creating a smooth, unified texture that feels pleasant on skin.
Effective at 9.03%
CAS #
9004-98-2
Form
Liquid
See origin →
Functions
Emulsifying
Forces oil and water to stay mixed instead of separating into layers. The unsung hero holding your lotion together.
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Emulsifier
Traditional Use
Synthetic surfactant and emulsifier developed in the mid-20th century by ethoxylating oleyl alcohol. These polyethylene glycol derivatives were created to provide stable emulsification and solubilization properties in cosmetics and pharmaceuticals.
Skin Types
●all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Yes
EWG
4
CIR
Safe w/Qualifications
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Concentration Guide
0.06%
18.0%
0%25%
Effective Range
CIR reported use: 0.1-18 | 0.3-10 | 1-4 | 0.06-10
Regulatory Agencies
Sensitization to oleth-3-phosphate and oleth-5 in a hair wax.
Abdullah A, Walker S, Tan CY, Foulds IS
Contact dermatitis, 1997
Sensitization to oleth-3-phosphate and oleth-5 in a hair wax.
Abdullah A, Walker S, Tan CY, Foulds IS
Contact dermatitis, 1997
Cetoleth-5
European Commission
EU Cosmetic Ingredient Database (CosIng)
Oleth-5
European Commission
EU Cosmetic Ingredient Database (CosIng)
Oleth-50
European Commission
EU Cosmetic Ingredient Database (CosIng)
Propylene Glycol Oleth-5
European Commission
EU Cosmetic Ingredient Database (CosIng)
Oleth-5
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Verified Feb 2026
Data: CosIng · EWG · CIR