Diatomaceous Earth is a non-toxic, safe substance made up from crushed fossils of freshwater organisms and marine life. Crushed to a fine powder and observed through a microscope, the particles resemble bits of broken glass. Deadly to any insect and completely harmless to animals, fish, fowl or food. Most insects have a waxy outer shell covering their bodies, INSECT STOP scratches through this shell causing the insect to dehydrate leading to eventual death.