Property: Appearance: Bronopol is supplied as crystals or crystalline powder, which may vary from white to pale yellow in colour depending on the grade of material being offered. Melting point: As a pure material, Bronopol has a melting point of about 130¦C. However due to its polymorphic characteristics, Bronopol undergoes a lattice rearrangement at 100 to 105¦C and this can often be wrongly interpreted as the melting point. At temperatures above 140¦C Bronopol will decompose exothermically releasing Hydrogen bromide and oxides of Nitrogen. Solubility: Bronopol is readily soluble in water although the dissolution process is endothermic. Solutions containing up to 28% w/v are possible at ambient temperature. Bronopol is poorly soluble in non-polar solvents but shows a high affinity for polar organic solvents.