Boric acid can be found in nearly any hardware store, grocery store or big box retail store, including Walmart, Home Depot and others. Boric acid is generally sold in the pesticide department.
Boric acid has been in use in the United States as an insecticide since 1948 when it was first used to control fleas, termites, fire ants, cockroaches, silverfish and other pests. The way it works is by affecting the metabolism of insects. In general, boric acid is considered to be safe for use in the home. Boric acid has other applications, including its use in curing of hides and in manufacturing industrial products, including fiberglass.