What is diatomaceous earth?
For this article, I’m leaning heavily on a very concise and clearly worded fact sheet from the National Pesticide Information Center (NPIC). This organization is a collaboration between the Environmental Protection Agency and Oregon State University and receives funding from no other sources.
Rather than describe what diatomaceous earth is, I’ll defer to NPIC.
Diatomaceous earth is made from the fossilized remains of tiny, aquatic organisms called diatoms. Their skeletons are made of a natural substance called silica. Over a long period of time, diatoms accumulated in the sediment of rivers, streams, lakes, and oceans. Today, silica deposits are mined from these areas.
Diatomaceous earth is not poisonous; it does not have to be eaten in order to be effective. Diatomaceous earth causes insects to dry out and die by absorbing the oils and fats from the cuticle of the insect’s exoskeleton. Its sharp edges are abrasive, speeding up the process.