Boric acid is used for pest control by injecting it into areas such as cracks and crevices. A fine dust layer of the substance is placed in the area being treated. Boric acid can be used as a dry powder or in a bait formulation containing an attractant food.
Boric acid should only be used in locations where it will not come into contact with people or animals, such as behind counters and baseboards. Application of the product should be done carefully, as it can produce adverse health effects if it is ingested or it comes into contact with the eyes or skin. However, it is generally considered to be a safe and effective alternative to spray insecticide products. Many boric acid formulations are effective for more than one year. While boric acid is somewhat slower acting than synthetic insecticides, it is effective over a long time period.
This insecticide adheres to the legs of an insect traveling through it, and causes death from starvation and dehydration after an insect ingests the substance while grooming itself. After ingestion, the insect dies three to 10 days later. Hatching insects that are exposed to boric acid also die, if the formulation does not become wet. Boric acid is used to control ants, grain weevils, several types of beetles and cockroaches. It also acts as a stomach poison for silverfish and termites, and it is abrasive to the insect’s exoskeleton.