Food grade diatomaceous earth is a sedimentary rock which crumbles into a fine, soft, white powder. It is fossilized marine phytoplankton from freshwater lakes. It is a powerful and non-toxic pesticide. When the diatomaceous powder touches bugs, it scrapes the insects waxy outer layer. The insects then lose their capacity to hold moisture, causing it to dry out. Diatomaceous earth benefits are effective in your home, garden, pets, and internally or externally for people.