preservative

Quaternium-15

Watch if sensitive·Strong evidence

A preservative that works by slowly releasing small amounts of formaldehyde to keep microbes from growing in the product. It is a well-documented contact allergen for a subset of users, which is why formaldehyde releasers are worth knowing about even though most people tolerate them fine.

Worth knowing

Known contact sensitizer for some
Restricted in the EU

Banned from cosmetic products sold in the EU and UK since 2019 following an SCCS safety opinion on formaldehyde release; still permitted in the US at regulated levels.

Gentler alternatives

Phenoxyethanol
Sodium Benzoate

Products with Quaternium-15

83
Clean & Clear
Foaming Facial Cleanser, Sensitive Skin

References

CosIng ingredient database (European Commission) ↗
CIR ingredient search ↗

Cosmetic information for general education, not medical advice. Concern is graded on cited evidence, never on hazard-score lists. See how we score.