Diazolidinyl Urea

A formaldehyde-releasing preservative that slowly gives off small amounts of formaldehyde to keep bacteria and mold from growing in the bottle. CIR set a maximum use level of 0.5%, at which released formaldehyde stays under generally accepted skin-safety thresholds, but people with a formaldehyde or fragrance-mix contact allergy sometimes react to it and may want to avoid the ingredient regardless of the low dose.

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