PEG-20 Sorbitan Isostearate
molecular structure · PubChem
AKA: Polysorbate 56, Sorbitan Isostearate PEG-20
Plant-Derived
Cleanser
Emulsifier
Not Clean
Sorbitan, monoisooctadecanoate, poly(oxy-1,2-ethanediyl) derivatives (20 mol EO average molar ratio)
CAS #
66794-58-9
Form
Liquid
Functions
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Emulsifying
Forces oil and water to stay mixed instead of separating into layers. The unsung hero holding your lotion together.
Surfactant Cleansing
Surfactant Emulsifying
Moisturizing
Strengthens Barrier
Lifts away dirt and oil
Mixes oil and water
Traditional Use
A modern synthetic emulsifier created by combining sorbitan (a sugar derivative) with isostearic acid and polyethylene glycol. Developed in the late 20th century to provide stable emulsification in cosmetic formulations with a plant-derived base.
EWG
3
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Regulatory Agencies
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewednone on file
⚖️Regulatory1 listing →
🛡️Safety-assessed3 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: CosIng · EWG · CIR