Is Boric Acid Safe?
The National Pesticide Information Center says boric acid and its sodium borate salts are pesticides found in nature and in many products, with borax one of the most common, and that they can be used to control insects, spiders, mites, algae, molds, fungi and weeds. Products containing boric acid have been registered for use in the United States since 1948.
NPIC says boric acid is low in toxicity if eaten or if it contacts skin, but that in the form of borax it can be corrosive to the eye and can also irritate the skin. It says people who have eaten boric acid have had nausea, vomiting, stomach aches and diarrhea, that diarrhea and vomit may have a blue-green color, and that eating extreme amounts has resulted in a red, boiled lobster like skin rash followed by skin loss.
On cancer, NPIC reports that the EPA concluded boric acid is not likely to be carcinogenic to humans, and that in experiments feeding mice and rats boric acid and borax for two years, no evidence that either causes cancer was found. For exposures, NPIC advises following the first aid instructions on the product label carefully and contacting the Poison Control Center at 800-222-1222 for additional treatment advice.
Sources checked September 15, 2026. Every point below links the page it came from.
The sources behind this answer
- Government sourceNPIC says boric acid and its sodium borate salts are pesticides found in nature and in many products, with borax one of the most common products. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC says boric acid and its salts can control insects, spiders, mites, algae, molds, fungi and weeds, and that products containing boric acid have been registered in the United States since 1948. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC says boric acid is low in toxicity if eaten or if it contacts skin, but in the form of borax it can be corrosive to the eye and can irritate the skin. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC says people who have eaten boric acid have had nausea, vomiting, stomach aches and diarrhea, and that eating extreme amounts has caused a red rash followed by skin loss. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC reports that the EPA concluded boric acid is not likely to be carcinogenic to humans, and that two-year feeding experiments in mice and rats found no evidence that boric acid or borax causes cancer. National Pesticide Information Center, Oregon State University ↗
- Government sourceNPIC advises following the first aid instructions on the product label carefully after any exposure, and contacting the Poison Control Center at 800-222-1222 for additional treatment advice. National Pesticide Information Center, Oregon State University ↗
Sources checked September 15, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.