What is Diatomaceous Earth? Diatomaceous Earth is a white talc-like powder made up of the remains of ancient, microscopic, sea-dwelling one-celled plants called diatoms. These diatoms grow in freshwater lakes or brackish bodies of water and absorb dissolved silica (silicon dioxide) in the water. Made up of approximately 86 percent silicon, this white powder-like substance is composed of millions of tiny sharp blades that look like shards of glass under the microscope. It has its various kinds of uses in different industries today, one of which is as a natural and effective alternative to insecticides. It kills its victims by puncturing the insects' exoskeleton with its sharp blades and absorbs body fluids killing the insects through dehydration. It is commonly used as such because of its effective bug-killing properties that do not contaminate the soil or harm worms and other organisms. Diatomaceous earth is composed of 82 percent silicon, 5 percent sodium, 2 percent iron and other trace minerals which it actually beneficial, not harmful, to the soil. You also will not have to worry about any side-effects when using the product, it is only harmful to insects, not humans. However, people with respiratory illnesses should keep out of contact from DE because it may cause respiratory problems, like coughing or sneezing, when inhaled. At small amounts, it is not at all harmful, its just that since our respiratory system is sensitive to powder-like substances, it is best to cover up when using this material.