Methyldibromo glutaronitrile

Methyldibromo glutaronitrile (MDBGN) is a widely used preservative.

Methyldibromo glutaronitrile

Names
IUPAC name 2-Bromo-2-(bromomethyl)-pentanedinitrile
Other names 1,2-Dibromo-2,4-dicyanobutane 1-Bromo-1-(bromomethyl)-1,3-propanedicarbonitrile 2-Bromo-2-(bromomethyl) glutaronitrile 2-Bromo-2-(bromomethyl)pentanedinitrile Bromothalonil Euxyl K400 Tektamer 38 Merquat 2200 Metacide 38
Identifiers
CAS Number	35691-65-7 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:62823
ChemSpider	55806
ECHA InfoCard	100.047.877
EC Number	252-681-0
PubChem CID	61948
UNII	YX089CPS05 Y
CompTox Dashboard (EPA)	DTXSID3024944
InChI InChI=1S/C6H6Br2N2/c7-4-6(8,5-10)2-1-3-9/h1-2,4H2 Key: DHVLDKHFGIVEIP-UHFFFAOYSA-N InChI=1/C6H6Br2N2/c7-4-6(8,5-10)2-1-3-9/h1-2,4H2 Key: DHVLDKHFGIVEIP-UHFFFAOYAK
SMILES C(CC(CBr)(C#N)Br)C#N
Properties
Chemical formula	C6H6Br2N2
Molar mass	265.936 g·mol−1
Appearance	White to yellow crystals
Melting point	51.2 to 52.5 °C (124.2 to 126.5 °F; 324.3 to 325.6 K)
Boiling point	212 °C (414 °F; 485 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

It is made by reacting bromine with 2-methyleneglutaronitrile below 30 °C. An allergy to the chemical can be discovered by performing a patch test.

History and allergy

In the mid-1980s, a maximum concentration of 0.1% in stay-on and rinse-off cosmetics was allowed.^[1] It was discovered soon afterwards that it caused allergic contact dermatitis to people with eczema.^[1]

It has been in use since the 1990s as a preservative in skin care products such as lotions, wet wipes, shampoo, and liquid soaps. Industrial applications include its use in preserving oils, glues, and medical gels.^[2]

In 2005, the EU banned its use in stay-on products,^[3] and in 2007 banned it in rinse-off products.^[1]

In 2005–06, methyldibromoglutaronitrile/ phenoxyethanol was the ninth-most-prevalent allergen in patch tests (5.8%).^[4]