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Diazolidinyl/Imidazolidinyl Urea

Diazolidinyl Urea is a preservative that prevents bacterial growth.
What it is
Diazolidinyl urea is produced by a chemical reaction to the process of heating and the addition of sodium hydroxide solution into allantoin and formaldehyde. The resulting reaction mixture is then neutralized with hydrochloric acid and then evaporated. Diazolidinyl Urea is a white powder
What it does
Diazolidinyl Urea is a preservative that prevents bacterial growth. It works by releasing small amounts of formaldehyde.
Side effects
Although Diazolidinyl releases toxic formaldehyde, the amounts are too small to pose a threat to human health. In Europe, when the concentration of formaldehyde in the finished product exceeds 0.05%, the labels has to state “contains formaldehyde”. However, Diazolidinyl Urea can cause irritations and allergies. There are alternatives and safer preservatives, rather avoid formaldehyde at all costs.
Imidazolidinyl urea
Imidazolidinyl urea is an antimicrobial preservative that works by forming formaldehyde in cosmetic products. People exposed to such formaldehyde-releasing ingredients may develop a formaldehyde allergy or an allergy to the ingredient itself. In the U.S. approximately 20% of cosmetics and personal care products contain a formaldehyde-releaser and the frequency of contact allergy to these ingredients is much higher among Americans compared to studies in Europe.

This ingredient may be derived from animals. From PETA's Caring Consumer: Excreted from urine and other bodily fluids. In deodorants, ammoniated dentifrices, mouthwashes, hair colorings, hand creams, lotions, shampoos, etc. Used to "brown" baked goods, such as pretzels. Derivatives: Imidazolidinyl Urea, Uric Acid. Alternatives: synthetics.