What it is
Diazolidinyl urea is a synthetic preservative that works by slowly releasing small amounts of formaldehyde, which inhibits the growth of bacteria and some fungi. It is water soluble and is often paired with other preservatives, such as parabens, to broaden coverage across the microbial spectrum. It is typically used at low concentrations within established usage limits.
Safety & warnings
As a formaldehyde releaser, diazolidinyl urea can be a contact allergen for some individuals, particularly those sensitive to formaldehyde, and it appears on standard patch-test panels. It is used within regulated concentration limits to manage exposure. It is not a comedogenic oil.
Origin & sourcing
Synthetic compound produced from allantoin chemistry and formaldehyde.
Questions everyone asks
What does diazolidinyl urea do?
It is a preservative that protects water-based formulas from bacteria and fungi by releasing small amounts of formaldehyde.
Can it cause allergies?
As a formaldehyde releaser it can trigger contact allergy in sensitized individuals, which is why it is used at low, regulated levels.