Boric acid is a water soluble chemical compound which has been used since the 1600s, when chemists first discovered that they could generate boric acid by treating borate with sulfuric acid. A wide variety of industries use boric acid, and the compound is often touted for its relatively low toxicity. A wide variety of products containing boric acid can be found on the market, ranging from insecticides to cosmetics, and pure boric acid is also available through some chemical suppliers and hardware stores.

Chemists know boric acid as H3BO4. The compound may be white or colorless, depending on its precise composition, and it is sold both in the form of a powder, and in a wet solution. Boric acid is a very mild acid, and it can be used for industrial processes like treating wood, fireproofing various materials, making cement, and creating controlled reactions in nuclear power plants. Boric acid also makes an excellent preservative and desiccant, and appears in the packaging for an assortment of products.

Boric acid also has a number of medicinal uses. It works as a mild antiseptic, and it can be effective in the treatment of some skin conditions such as acne and mild rashes. Boric acid also works on yeast and fungal infections, and, in a diluted form, it can be used as an eyewash. The compound is also a effective low-toxicity fungicide which can be used to control pests like ants and cockroaches.

While boric acid is of low toxicity, it can be dangerous. Some animals appear to bioaccumulate borates, which means that long-term exposure can cause health problems. Boric acid can also be deadly when ingested, and prolonged use of boric acid on the skin or in the eyes can cause irritation. It can also be harmful to household pets, who reach lethal levels of exposure more quickly than humans, thanks to their smaller size.

If boric acid is used for things like household pest control, it should be applied carefully, and ingestion should be avoided. Topical applications of boric acid should avoid mucus membranes and breaks in the skin, which could provide a route for boric acid to enter the body, and boric acid use should be discontinued if an irritation develops. It is also a good idea to discuss the use of boric acid with a doctor, to ensure that you do not have any medical conditions or use medications which could contraindicate the use of boric acid.