Diatomaceous earth is a natural and easy-to-use insecticide that you can use around your home. The product is actually a soft, sedimentary rock that's made of fossilized marine organisms called diatoms.
It's available in powder form and can be used to eliminate cockroaches, silverfish, ants, and fleas. Just dust the powder on the floor or other surfaces where you suspect the insects have been crawling. The tiny, sharp particles within diatomaceous earth will cut into an insect's waxy exoskeleton and cause it to dehydrate and die. Insects that ingest the powder will also die.
Keep in mind that you many need to apply the product repeatedly if your house is humid, since the powder must stay dry in order to be an effective insecticide.