Potassium C12-13 Alkyl Phosphate
AKA “Anionic surfactant, Soap
Synthetic
Ingredient Facts
Potassium c12-13 alkyl phosphate
AKA: Anionic surfactant, Soap
Synthetic · Cleansing · EWG: 4
Synthetic
Cleanser
Emulsifier
Synthetic
Clean
Potassium salt of a complex mixture of esters of phosphoric acid and C12-13 alcohols Science: Functions: Surfactant - Cleansing Safety Ratings: CIR: Safe as used
Effective at 4.18%
CAS #
90506-45-9; 17026-85-6; 19035-79-1; 84861-79-0; 190454-07-0; 39322-78-6
Form
Powder
See origin →
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.
Cleansing Surfactant
Removes Impurities
Traditional Use
A synthetic surfactant developed in the mid-20th century for cosmetic formulations. No traditional use; created as an emulsifier and cleansing agent in contemporary skincare products.
Skin Types
all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Caution
EWG
4
CIR
Insufficient
Pregnancy
Caution
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Concentration Guide
0.05%
8.3%
0%12%
Effective Range
CIR reported use: 0.05-8.3
Regulatory Status
USAunder review
EUrestricted
JAPANrestricted
CANADArestricted
Potassium C12-13 Alkyl Phosphate
European Commission
EU Cosmetic Ingredient Database (CosIng)
quillaja saponaria (soapbark) bark extract
European Commission
EU Cosmetic Ingredient Database (CosIng)
Potassium C12-13 Alkyl Phosphate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
quillaja saponaria (soapbark) bark extract
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Occupational contact dermatitis caused by sodium cocoamphopropionate in a liquid soap used in fast-food restaurants.
Hagvall L, Bråred-Christensson J, Inerot A
Contact dermatitis, 2014
Natural soap is clinically effective and less toxic and more biodegradable in aquatic organisms and human skin cells than synthetic detergents.
Kanyama T, Masunaga A, Kawahara T, Morita H, Akita S
PloS one, 2025
Natural soap is clinically effective and less toxic and more biodegradable in aquatic organisms and human skin cells than synthetic detergents.
Kanyama T, Masunaga A, Kawahara T, Morita H, Akita S
PloS one, 2025
Occupational immediate type allergy to soapnut and quillaja bark.
Merget R, Raulf M, Sander I
Allergologie select, 2021
Morphological study of cationic polymer-anionic surfactant complex precipitated in solution during the dilution process.
Miyake M, Kakizawa Y
Journal of cosmetic science, 2010
Clinical Evaluation of a Soap-Free Cleansing Lotion Containing Sodium Cocoyl Apple Amino Acids for Effective Impurity Removal and Skin Barrier Preserv
Patel M, Khatri A, Khatri R, Sreevallabhan S, Jose S et al.
Cureus, 2025
Verified Feb 2026
Data: CosIng · EWG · CIR