<sigh>
Yes, yes DNP has been used as an explosive igniter and as an insect/rodent poison. However, consider this:
Several years ago before he had heart surgery, my father was prescribed
nitroglycerin (an
explosive!) for
angina. He carried the tablets in a small metal canister so they wouldn't be in contact with his skin. Having worked on a blasting crew one summer during college, I can assure you that just getting a little dynamite paste on your hand is enough to give you a major headache from your blood vessels dilating. However for heart patients, this is a good thing.
A few years before that my sister was in the hospital and while she connected up to an IV, they administered
Warfarin (a
rat poison!) to prevent blood clotting. A rodenticide administered to a person by doctors in a hospital no less!
My point here is that chemicals can have many uses - the fact that something has one use does not prevent it from also having beneficial medical uses. The difference between a toxin and a medicine is often just a matter of dosage and context.