Undecylenic Acid
AKA “Undec-10-enoic acid, 10-UNDECENOIC ACID, 112-38-9, 10-Hendecenoic acid, Renselin, Declid, Sevinon, 10-Undecylenic acid, undecylenate”
Acid
Ingredient Facts
Undecylenic acid
AKA: Undec-10-enoic acid, 10-UNDECENOIC ACID, 112-38-9, 10-Hendecenoic acid, Renselin, Declid, Sevinon, 10-Undecylenic acid, Undecylenate
Acid · Antimicrobial · EWG: 2
Synthetic
Preservative
Cleanser
Emulsifier
Acid
Clean
Undec-10-enoic acid; 10-Undecenoic acid
Solubility Insoluble
Formula
C11H20O2
Mol. Weight
184.27
CAS #
112-38-9
Form
Liquid
State
Liquid
See origin →
Functions
Antimicrobial
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
Preservative
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
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.
Fights Bacteria
Traditional Use
Derived from castor oil in the early 20th century. Historically used in traditional medicine for fungal infections; later adopted by cosmetic chemists as an antimicrobial and antifungal ingredient in skincare products.
Skin Types
●all-skin-types
Best For
Acne
Pregnancy & Breastfeeding Safe
Caution
EWG
2
CIR
Safe as used
Pregnancy
Caution
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Concentration Guide
0.2%
0%0%
Reg. Limit
EU regulatory limit: 0.2%. Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 18.
Regulatory Agencies
RIFM fragrance ingredient safety assessment, 10-undecenoic acid, heptyl ester, CAS Registry Number 68141-27-5.
Api AM, Belsito D, Botelho D, Bruze M, Burton GA Jr et al.
Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 2018
Efficacy of undecylenic acid-zinc undecylenate powder in culture positive tinea pedis.
Chretien JH, Esswein JG, Sharpe LM, Kiely JJ, Lyddon FE
International journal of dermatology, 1980
Calcium Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Heptyl Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
MEA-Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Polyglyceryl-10 Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Polyglyceryl-6 Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Potassium Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sodium Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Sorbitan Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
TEA-Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Undecylenic Acid
European Commission
EU Cosmetic Ingredient Database (CosIng)
Zinc Undecylenate
European Commission
EU Cosmetic Ingredient Database (CosIng)
Novel Formulation of Undecylenic Acid induces Tumor Cell ...
Zoe I Day, Alyce J Mayfosh, Marie-Claire Giel, Yuning Hong, Scott A Williams, Jascinta P Santavanond + 3 more
International journal of molecular sciences, 2022
Glyceryl Undecylenate
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Undecylenic Acid
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Molecular modeling and phenoloxidase inhibitory activity of arbutin and arbutin undecylenic acid ester.
Masyita A, Salim E, Asri RM, Nainu F, Hori A et al.
Biochemical and biophysical research communications, 2021
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR