High concernPreservative
Bronopol
Formaldehyde releaserKnown carcinogenSkin irritantAllergen
What it is
A brominated aliphatic alcohol that generates formaldehyde on decomposition and can form carcinogenic nitrosamines in the presence of amine compounds.
What it does
Antimicrobial preservative for cosmetics, pharmaceuticals, and industrial systems.
Why it’s a concern
Besides releasing formaldehyde, bronopol can react with secondary or tertiary amines (triethanolamine, DEA, TEA) in the same formulation to form N-nitrosamines, several of which are classified by IARC as probable human carcinogens. The EU restricts bronopol to rinse-off products at 0.1% maximum and disallows it in products with amines.
Also known as
2-bromo-2-nitropropane-1,3-diol
CAS numbers
52-51-7
Commonly found in
shampoolotioncleansers
Safer alternatives
- sodium benzoate
- phenoxyethanol
- glyceryl caprylate
Related chemical families
Sources
- SCCS Opinion on Bronopol
- IARC Monographs on Nitrosamines