| Description | 1,2-Dibromo-2,4-dicyanobutane is the main sensitizer of Euxyl K400, a widely used preservative agent in cosmetics, toiletries or metalwork fluids.
Methyldibromo glutaronitrile (MDBGN), also known as dibromocyanobutane, is to be found in the preservative system Euxyl K 400 (also called Tektamer 38), which is a mix of MDBGN and phenoxyethanol in a ratio of 1:4. Euxyl K 400 is a broad‐spectrum preservative with activity against fungi and bacteria. MDBGN is nearly always the allergen when sensitization to Euxyl K 400 occurs. |
| Chemical Properties | Light yellow crystalline solid or powder.Commercial products may be soluble concentrate (liquid orsolid); pellets/tablets. Mild, acrid, sweet odor. |
| Occurrence | MDBGN was historically widely used in cosmetics, sunscreens, shampoos, liquid soaps, and barrier and moisturizing creams used at work. Other sources include moistened toilet tissues, ultrasound gel, adhesives, soluble cutting oils, latex paints, vaginal examination gel and sanitary pads. The EU ban has reduced these exposures very signifi cantly. Nevertheless, its inclusion in products used in the workplace such as barrier creams and after‐work creams makes its inclusion in the European and BSCA baseline series still relevant at the current time. |
| Uses | 1,2-Dibromo-2,4-dicyanobutane is a preservative for metalworking fluids, cosmetics, adhesives, latex emulsions and paints, dispersed pigments and detergents; active ingredient in Euxyl K 400 and Tektamer 38. |
| Definition | ChEBI: An organobromine compound that consists of pentanedinitrile bearing bromo and bromomethyl substituents at position 2. |
| General Description | Crystals with a pungent odor. Insoluble in water. Used as a preservative in latex paint, adhesives, etc. |
| Air & Water Reactions | Insoluble in water. |
| Reactivity Profile | DBDCB may polymerize in the presence of metals and some metal compounds. Incompatible with acids; mixing nitriles with strong oxidizing acids can lead to extremely violent reactions. Nitriles are generally incompatible with other oxidizing agents such as peroxides and epoxides. The combination of bases and nitriles can produce hydrogen cyanide. Nitriles are hydrolyzed in both aqueous acid and base to give carboxylic acids (or salts of carboxylic acids). These reactions generate heat. Peroxides convert nitriles to amides. Nitriles can react vigorously with reducing agents. |
| Agricultural Uses | Microbiocide: Tolerances have been established by the U.S. Foodand Drug Administration when this substances is used asa preservative in food-grade adhesives and as a slimicidein the manufacture of food-grade paper and paperboard.Used to control slime-forming bacteria and fungi in recirculatingwater cooling system; oil-recovery drilling mudsystems; paper mill and pulp mill water systems and similarindustrial processing and chemical systems. |
| Trade name | BIOCHEK®; BIOCLEAR®; MERCK®48051; METACIDE® 38; METASOL; TEKTAMER |
| Contact allergens | Methyldibromo glutaronitrile is a biocide widely used as a preservative agent in cosmetics, toiletries, and metalworking fluids. It is a potent allergen, banned in all cosmetics in the EU since 2007. |
| Safety Profile | Experimental reproductive effects. When heated to decomposition it emits toxic fumes of NO, and Br-. |
| Potential Exposure | Nitrile microbiocide used as a preser-vative in food grade adhesives and as a slimicide in themanufacture of food grade paper and paperboard; used tocontrol slime-forming bacteria and fungi in recirculatingwater cooling system; oil recovery drilling mud systems;paper mill and pulp mill water systems and similar indus-trial processing and chemical systems. |
| Shipping | UN3261 Corrosive solid, acidic, organic, n.o.s.,Hazard class: 8; Labels: 8-Corrosive material, TechnicalName Required. UN3439 Nitriles, solid, toxic, n.o.s.,Hazard Class: 6.1; Labels: 6.1-Poisonous materials,Technical Name Required. |
| Incompatibilities | Corrosive. Strong oxidizers and reducingagents, strong acids and bases. Reacts with acids, steam,warm water producing toxic and flammable hydrogen cya-nide fumes. Hydrogen cyanide is produced when propioni-trile is heated to decomposition. Nitriles may polymerize inthe presence of metals and some metal compounds. Theyare incompatible with acids; mixing nitriles with strongoxidizing acids can lead to extremely violent reactions.Nitriles are generally incompatible with other oxidizingagents such as peroxides and epoxides. The combination of bases and nitriles can produce hydrogen cyanide. Nitrilesare hydrolyzed in both aqueous acid and base to give car-boxylic acids (or salts of carboxylic acids). These reactionsgenerate heat. Peroxides convert nitriles to amides. Nitrilescan react vigorously with reducing agents. Acetonitrile andpropionitrile are soluble in water, but nitriles higher thanpropionitrile have low aqueous solubility. They are alsoinsoluble in aqueous acids. |
| Waste Disposal | Recycle any unused portionof the material for its approved use or return it to the manu-facturer or supplier. Ultimate disposal of the chemical mustconsider: the material’s impact on air quality; potentialmigration in soil or water; effects on animal, aquatic, andplant life; and conformance with environmental and publichealth regulations. |
