Ingredient

quaternium-15

High risk

FunctionPreservative

What it is — Quaternium-15 (INCI: Quaternium-15) is a preservative that works by slowly releasing small amounts of formaldehyde to protect products from microbial growth.

What it does — It helps keep water-containing formulas safe and stable over their shelf life by inhibiting bacteria, mould and yeast.

Typical use — Historically used across skincare, haircare and cosmetics, though it has become less common as brands move to alternative preservatives.

Who it suits / good to know — It is one of the more common contact allergens among preservatives, so those with sensitive skin or a known preservative or formaldehyde allergy will likely want to avoid it and check the INCI list. Formaldehyde-releaser-free options are widely available.

Safety — DHALIORA grades it high risk: a formaldehyde-releasing preservative associated with contact allergy and irritation. This reflects the ingredient in general and is not medical advice; patch-test before use and discontinue if any reaction occurs.

Why we grade it High: High risk - formaldehyde-releasing preservative associated with contact allergy and irritation.
Cross-reference

Found in these DHALIORA products

Found in 0 DHALIORA products

Not currently in any DHALIORA product.

How grades are set — Risk reflects our own reading of publicly available safety data, an EWG-style reading shown at the worst-case grade we've assigned this ingredient across products. It isn't a third party's proprietary score, and it isn't medical advice. Always read the packaging and patch-test where indicated.
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