a method for desensitizing explosives illicitly manufactured from commercial fertilizers , preferably ammonium nitrate . ammonium nitrate prills are impregnated with microballoons which carry a desensitizing agent , preferably water . the microballoons are sufficiently small that they can be incorporated into the prills where they are not easily separated . should the modified ammonium nitrate be used as a starting material for the manufacture of anfo , the resulting anfo exhibits a diminished explosive potential . the microballoons release their contents in response to a prompt shock wave which passes through the anfo . the released water quenches the explosive reactions in an / fuel compositions and curtails the explosive performance of the anfo . further , the microballoons are a benign additive having no adverse impact on the fertilizer itself , the plant material or the environment if it is instead used for its intended purpose as a fertilizer .