Octoxynol-9 Carboxylic Acid

Octoxynol-9 Carboxylic Acid 1
molecular structure · PubChem CID 168358
AKA: 3, 6, 12, 15, 18, 21, 24-Octaoxahexacosanoic acid, PEG-9 Octyl phenyl ether carboxylic acid, 25338-58-3, 2-[2-[2-[2-[2-[2-[2-[2-[2-(2-octylphenoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]acetic acid, 26-(Octylphenoxy)-3, 24-octaoxahexacosanoic acid, 26-(2-OCTYLPHENOXY)-3, 24-OCTAOXAHEXACOSANOIC ACID, 26-(2-octylphenoxy)-3, 24-octaoxahexacosan-1-oic acid
Synthetic
Cleanser
Acid
Not Clean
OriginDerived from polyethylene glycol and nonylphenol, belonging to the nonionic surfactant chemical family. Synthesized through ethoxylation and subsequent carboxylation of nonylphenol-based precursors.
26-(Octylphenoxy)-3,6,9,12,15,18,21,24-octaoxahexacosanoic acid
Formula
C32H56O11
Mol. Weight
616.80
CAS #
25338-58-3
Form
Liquid
State
Solid
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
Functions
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Cleansing Surfactant
Antioxidant Protection
Reduces Inflammation
Locks In Moisture
Removes Impurities
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.
EWG
4
CIR
Safe as used
Pregnancy
Yes
Concentration Guide
CIR lists it as not reported to be in use.
CIR · report published 2025
Regulatory Status
USA✔ permitted
EU⚠ restricted
JAPAN⚠ restricted
CANADA⚠ restricted
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR