Steartrimonium Bromide
molecular structure · PubChem
AKA: 1120-02-1, Octadecyltrimethylammonium bromide, CATINAL STB, ODTEA Br cpd
Plant-Derived
Preservative
Skin Conditioner
Hair Care
Not Clean
Trimethyloctadecylammonium bromide
Formula
C21H46BrN
Mol. Weight
392.50
CAS #
1120-02-1
Form
Liquid
Functions
Antistatic
Hair Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Preservative
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
Reduces Static
Conditions Hair
Preserves Formula
Reduces flyaways
Softens and detangles hair
Prevents microbial growth
Traditional Use
Developed in the 1950s as a quaternary ammonium compound for hair and skincare. Created to provide antistatic and conditioning properties, replacing some traditional botanical surfactants.
EWG
3
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Concentration Guide
0.1%
0%0%
Reg. Limit
EU regulatory limit: 0.1%. Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 44.
Regulatory Agencies
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewednone on file
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR