PEG-Cetyl Stearyl Diether
AKA “PEGylated Fatty Alcohol Ether
Synthetic
Ingredient Facts
Peg-cetyl stearyl diether
AKA: PEGylated Fatty Alcohol Ether
Synthetic · Emollient · EWG: 4
Plant-Derived Synthetic
Emollient
Cleanser
Emulsifier
Skin Conditioner
Plant Oil
Synthetic
Clean
Science: Origin: Botanic/Natural | Process: Ethoxylation Safety Ratings: CIR: Safe as used
CAS #
9002-92-0; 68439-50-9; 5274-68-0; 9004-95-9; 9005-00-9; 4536-30-5; 3055-93-4; 3055-94-5; 3055-95-6
See origin →
Functions
Emollient
Fills in the tiny cracks between skin cells to make everything feel smooth and soft. The "silky finish" ingredient.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Emulsifying
Forces oil and water to stay mixed instead of separating into layers. The unsung hero holding your lotion together.
Traditional Use
A synthetic ether compound created in the 20th century by combining polyethylene glycol with fatty alcohols. Developed as an emulsifier and conditioning agent for cosmetics with no traditional precedent.
Skin Types
all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Yes
EWG
4
CIR
Safe
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Regulatory Status
USApermitted
EUrestricted
JAPANrestricted
CANADArestricted
Verified Feb 2026
Data: CosIng · EWG · CIR