preservative
Imidazolidinyl Urea
Watch if sensitive·Strong evidence
A formaldehyde-releasing preservative used to extend shelf life. It is one of the more frequently reported contact-allergy triggers among preservatives, so people with sensitive or eczema-prone skin, or a known formaldehyde allergy, may want to patch test or avoid it.
Worth knowing
- Known contact sensitizer for some
- Can irritate, especially left on
- Restricted in the EU
Permitted in the EU up to a set maximum concentration, with a formaldehyde warning label required above 0.05% free formaldehyde.
Gentler alternatives
Products with Imidazolidinyl Urea
References
Cosmetic information for general education, not medical advice. Concern is graded on cited evidence, never on hazard-score lists. See how we score.