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Diazolidinyl Urea

What-it-does: preservative


An antimicrobial preservative that helps your products not to go wrong too quickly. It works especially well against bacteria, specifically gram-negative species, yeast, and mold.

Somewhat controversial, it belongs to an infamous family of formaldehyde-releasers. That is, it slowly breaks down to form formaldehyde when it is added to a formula. We have written more about formaldehyde-releasing preservatives and the concerns around them at Dmdm Hydantoin, but do not get too scared, those are more theories than proven facts.

As for Diazolidinyl Urea itself, a study from 1990 writes that at concentrations up to 0.4%, it was a mild cumulative skin irritant, but the CIR (Cosmetic Ingredient Review) reviewed it in 2006 and found that, in concentrations of <0.5%, it is safe as used, as the amount of formaldehyde released will be smaller than the recommended limit (of less than 0.2%).

All in all, it is up to your personal decision and skin sensitivity. 

Show me some proof

  • Liebert, M. A. "Final report on the safety assessment of diazolidinyl urea." J. Am. Coll. Toxicol 9 (1990): 229-245.

Products with Diazolidinyl Urea

Forever Aloe Ever-Shield Deodorant Stick Acneology Clarifying Toner Laca Loción Con Adn Marino O Cosmedics Mineral Pro SPF 30+ Spatagonia Agua Termal Thursday Plantation Aloe Vera Gel iNova Pharmaceuticals ReTrieve Cream with Tretinoin Idraet Serum Hialuronico Linoderm Pantenol Sprej Metrin Reactivating Gel Monu Skin Gentle Toner Monu Skin Rosewood Reviving Mist MyLABEL Love Skin Água De Rosas Rosto Natural Concepts Aloe Post Wax Skin Soother Needs Face Água Micelar OXY Emergency Wash PROSACEA Medicated Rosacea Gel SunSense Anti-Ageing Face Spf 50+ Sunscreen Tiger balm Neck & Shoulder Rub Uremol Urea 10% Cream Urisec 22% Urea Cream standard. Lactic Acid 5% Toner With Aha Toner BeautyRX Clarifying Toner CULLUN Tropical Bio-Toning Essence Care Science Natural Wound Gel With Tea Tree Celuflex AR Serum De Alta Potencia Creme classique Safari SPF 40 Derma V10 Stimulating Eye Roll On With Caffeine DermaVix Anti Aging Formula Endocil Freshening Skin Toner HydroSkinCare Ha² Serum Lagos Celluflex C Serum Alta Potencia Lidherma Fórmula jabón liquido Luron Soothing Aloe Vera Gel Monu Skin Clarifying Toner OXY Deep Pore Acne Vanishing Treatment Premium Nature Aloe Vera Gel Proactiv Emergency Blemish Relief Skin Actives Scientific Palmitoyl Pentapeptide-3 Skin V.2.0 Niacinamide Serum Smooth É Smooth E White Babyface Cleansing Gel SunSense Anti-Ageing Face Sunew med+ Epidermal Dissolving Face Gel Violetta Good Night Aloe Vera Australia Aloe Skin & Hair Gel Bimaio Serum Hialurónico Puro Cathy Doll Toner Essence Caviahue Serum C Dauf Sabonete Esfoliante Facial Dermaglin Refreshing Peeling Mask