Diethanolamine
AKA “2'-Iminodiethanol, Diolamine, Iminodiethanol, Bis(2-hydroxyethyl)amine, 2-(2-Hydroxyethylamino)ethanol, Diethanolamin, Diethylolamine, 2'-Dihydroxydiethylamine”
Synthetic
Ingredient Facts
Diethanolamine
AKA: 2'-Iminodiethanol, Diolamine, Iminodiethanol, Bis(2-hydroxyethyl)amine, 2-(2-Hydroxyethylamino)ethanol, Diethylolamine, 2'-Dihydroxydiethylamine
Synthetic · Buffering · EWG: 4
Synthetic
Synthetic
Clean
A pH balancer that helps keep our formula at the right acidity level for your skin and hair.
Solubility greater than or equal to 100 mg/mL at 57 °F (NTP, 1992)
Formula
C4H11NO2
Mol. Weight
105.14
CAS #
111-42-2
Form
Liquid
State
Diethanolamine appears as oily colorless liquid or solid white crystals. Slight rotten fish or ammonia odor. Denser than water. (USCG, 1999)
See origin →
Functions
Buffering
pH Adjuster
Quells irritation
Traditional Use
Organic compound synthesized in the early 20th century from ethylene oxide and ammonia. Adopted widely in cosmetics in the 1950s as a pH buffer and emulsifying agent, particularly in creams and shampoos.
Skin Types
●all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Yes
EWG
4
CIR
Safe w/Qualifications
Pregnancy
Yes
Restricted By
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Regulatory Agencies
Final Report on the Safety Assessment of Triethanolamine, Diethanolamine, and Monoethanolamine
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Safety Assessment of Diethanolamine and Its Salts as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
Diethanolamine
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
Safety Assessment of Diethanolamine and Its Salts as Used...
Monice M Fiume, Bart Heldreth, Wilma F Bergfeld, Donald V Belsito, Ronald A Hill, Curtis D Klaassen + 6 more
International journal of toxicology, 2017
Safety Assessment of Diethanolamine and Its Salts as Used...
Monice M Fiume, Bart Heldreth, Wilma F Bergfeld, Donald V Belsito, Ronald A Hill, Curtis D Klaassen + 6 more
International journal of toxicology, 2017
Safety Assessment of Diethanolamine and Its Salts as Used...
Monice M Fiume, Bart Heldreth, Wilma F Bergfeld, Donald V Belsito, Ronald A Hill, Curtis D Klaassen + 6 more
International journal of toxicology, 2017
Formation and inhibition of N-nitrosodiethanolamine in cosmetics under pH, temperature, and fluorescent, ultraviolet, and visual light.
Lim DS, Lim SK, Kim MK, Kwon YC, Roh TH et al.
Journal of toxicology and environmental health. Part A, 2018
Allergic contact dermatitis caused by cocamide diethanolamine.
Mertens S, Gilissen L, Goossens A
Contact dermatitis, 2016
Verified Feb 2026
Data: PubChem · CosIng · EWG · CIR