Quaternium-15
Notable concerns
INCI · Quaternium-15CAS 51229-78-8
Also known as: Dowicil 200 · Hexamethylenetetramine chloroallyl chloride
Preservative
In plain language
A highly effective, broad-spectrum preservative that prevents bacterial growth by releasing formaldehyde.
A known formaldehyde-releaser and a frequent cause of allergic contact dermatitis.
Concerns & harms
Concern
Formaldehyde Release
Releases formaldehyde to kill microbes, posing sensitization and carcinogenic risks over prolonged exposure.
Strong evidence
Where it can be sold
Simplified regulatory status by market — for guidance, not compliance advice.
European UnionNot permitted
Banned from use in cosmetics in the EU due to its CMR classification.
01
Contact allergy to preservatives. I. Formaldehyde-releasers. ↗
Contact Dermatitis · 1992
Peer-reviewed