High concernPreservative
Quaternium-15
Formaldehyde releaserKnown carcinogenAllergenSkin irritant
What it is
A quaternary ammonium salt that decomposes slowly in water to release formaldehyde.
What it does
Broad-spectrum preservative in cosmetics, industrial cutting fluids, and some household cleaners.
Why it’s a concern
Named the American Contact Dermatitis Society Allergen of the Year in 2005 as the single most common cause of preservative-related contact dermatitis. Releases free formaldehyde (IARC Group 1 carcinogen) in formulations. Banned in EU cosmetics since 2017.
Also known as
dowicil 2001-(3-chloroallyl)-3,5,7-triaza-1-azoniaadamantane chloride
CAS numbers
4080-31-3
Commonly found in
lotionshampoocleaning products
Safer alternatives
- sodium benzoate
- phenoxyethanol
- potassium sorbate
Related chemical families
Sources
- ACDS Allergen of the Year 2005
- EU Cosmetics Regulation Annex II