Imidazolidinyl urea

Imidazolidinyl urea kills gram-negative bacteria. It acts synergistically with parabens to provide a broad-spectrum antibiotic that is effective against mold, yeast, and bacteria. The combination of the two chemicals constitutes the most widely used preservative in cosmetics. 

Imidazolidinyl urea works by releasing formaldehyde into the product, just like the related preservative DMDM hydantoin. 

Isothiazolinones are a class of broad-spectrum biocides used as preservatives in many household and industrial products. They are used in cosmetics and shampoos as a biocide to kill fungi and bacteria. Unlike the preservatives DMDM hydantoin and imidazolidinyl urea, also commonly used in these products, isothiazolinones do not release formaldehyde, to which some people are sensitive. On the other hand, some people are sensitive to isothiazolinones. 

Another formaldehyde-releasing preservative is imidazolidinyl urea (see page 36). 

IMIDAZOLIDINYL UREA Water soluble Poor antifungal activity 1... 

Dioxacyclopentane, d734 3,6-Dioxa-l,ll-undecanediol, t430 (2,5-Dioxo-4-imidazolidinyl)urea, a71... 

Preservatives. Most products must contain preservatives to ensure that yeasts, molds, and bacteria do not thrive in them. These preservatives include alcohol, methylparaben, propylparaben, DMDM hydantoin, diazolidinyl urea, and imidazolidinyl urea. The parabens have limited solubility in water, eg, 0.25% for methylparaben and 0.05% for propylparaben (22). If these levels are exceeded in the formula, then the addition of solvents is needed to ensure clear, stable products. 

Preservative l,3-Dimethylol-5,5-dimethyl hydantoin, Quarternium-15 [INCI nomenclature CAS 4080-31-3] Imidazolidinyl urea, parabens phenoxyethanol... 

Formaldehyde-releasing preservatives, such as quater-nium-15, diazolidinyl urea, and imidazolidinyl urea, are widely used in cosmetics and topical medications and are well-known contact sensitizers. In spite of positive patch test reactions to these preservatives in a number of patients, only some of these patients will react when they use the corresponding commercial formulations. This is because the concentrations of preservatives in the commercial products are often below the threshold necessary to produce a clinical reaction. This finding confirms the importance of using commercial formulations of topical agents in estimating the clinical relevance of patch test results (10). 

Preservatives that are often found in cosmetics include formaldehyde, quaternium-15, imidazolidinyl urea, diazo-lidinyl urea, parabens mix, 5-chloro-2-methyl-4-isothiazo-lin-3-one + 2-methyl-4-isothiazolin-3-one (MCI/MI, Kathon CG), and methyldibromoglutaronitrile (MDBGN, Euxyl K400). Polyhexamethylenebiguanide, a biocide structurally related to hexamidine, is added to cosmetics as a preservative. 

Biopure 100 Germall 115 imidazolidinyl urea methanebis[N,N (5-ureido-2,4-diketotetrahydroimidazole)-N,N-dimethylol] l,l -methylenebis 3-[3-(hydroxymethyl)-2,5-dioxo-4-imidazolidinyI]urea Tri-Stat IJJ. 

Rosen WE, Berke PA, Matzin T, Peterson AF. Preservation of cosmetic lotions with imidazolidinyl urea plus parabens. ] Soc Cosmet Chem 1977 28 83-87. 

Berke PA, Rosen WE. Imidazolidinyl urea activity against pseudomonas. ] Soc Cosmet Chem 1978 29 757—766. 

Wallhausser KH. Imidazolidinyl urea. In Kabara JJ, ed. Cosmetic and Drug Preservation Principles and Practice. New York Marcel Dekker, 1984 655-657. 

Dooms-Goossens A, De Boulle K, Dooms M, Degreef H. Imidazolidinyl urea dermatitis. Contact Dermatitis 1986 14(5) 322-324. 

O Brien TJ. Imidazolidinyl urea (Germall 115) causing cosmetic dermatitis. Aust J Dermatol 1987 28(1) 36—37. 

Ziegler V, Ziegler B, Kipping D. Dose-response sensitization experiments with imidazolidinyl urea. Contact Dermatitis 1988 19(3) 236-237. 

Elder RL. Final report of the safety assessment for imidazolidinyl urea. / Environ Pathol Toxicol 1980 4(4) 133—146. 

Preservatives can be classified into two types compounds that release formaldehyde and compounds that do not release formaldehyde. Formalin, an aqueous solution of formaldehyde, is a commonly used preservative in shampoos and conditioners [3], Although formaldehyde has been known as a sensitizer, it is not a problem if used at 0.1 % or lower. The use of formaldehyde in baby shampoos is not recommended. Other preservatives that fall in the formaldehyde-releasing group are diazolidinyl urea, imidazolidinyl urea, and DMDM (dimethyloldimethyl) hydantoin. 

Preservatives Antimicrobial Benzalkonium chloride Benzyl alcohol Chlorhexidine Imidazolidinyl urea Phenol Potassium sorbate 1 Benzoic acid Bronopol Chlorocresol Paraben esters Phenoxyethanol Sorbic acid Antioxidants a-Tocopherol Ascorbic acid Ascorbyl palmitate Butylated hydroxyanisole Butylated hydroxytoluene Sodium ascorbate Sodium metabisulphite Chelating agents Citric acid Edetic acid... 

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