Many people are concerned about whether borax is a safe chemical. There are many sites on the internet claiming it is toxic. I disagree with these sites and believe that borax is as safe for household use as table salt or washing soda—in other words, the dose makes the poison. Here’s why…
History of Borax
Humans have mined and used borax (also known as sodium tetraborate) since its discovery in Persia more than 4,000 years ago. Borax is a naturally occurring mineral found in concentration in dried salt lake beds, and consists of water, sodium, boron and oxygen. That’s it. The main areas where borax is mined today are in Turkey and California.
Boron is an essential trace mineral nutrient required for many functions in the body, like rebuilding bone and teeth, hormone regulation, absorption and metabolism of calcium, magnesium and phosphorus, and maintaining communication between your cells.
In fact, boron is as essential for the parathyroid gland as iodine is for the thyroid.
Boron is ubiquitous in soil and water, and is required for plant growth. Diets with a fair amount of fruit and vegetables provide about 2 to 5 mg of boron per day, but this also depends on the region where the food was grown and how it was grown.
The Evidence on Borax
All of the studies that showed evidence of possible hormone disruption in animals either used ridiculously high doses of borax (many grams delivered intravenously), or they conflated borax with boric acid, which is NOT the same stuff.
Borax (sodium tetraborate) is used in the process of making boric acid, but there is a tremendous chemical difference between the two. Many of the studies used to demonstrate the alleged danger of borax often used boric acid instead, or were ambiguous about which was used.
Boric acid is toxic at far lower doses than borax, so any study that isn’t clear about which of the two is used for the data should not be considered credible. (This includes the EWG data.)
Borax can be toxic at the high doses used in animal studies. It has this effect at high doses is because it is essentially an overdose of the element boron. Iron, zinc and calcium are required by the body too, but an overdose of any of these will also send you to the hospital, or even kill you!
However, adults would never ingest anything even close to the amount of borax required to do harm—unless they worked unprotected for years in a borax mine or packaging factory. However, you will want to keep your small children and pets out of the borax, just as you would keep them away from the chewable vitamins. An overdose of boron can be as dangerous as an overdose of zinc or iron, especially for small bodies.
Borax is officially classified as non-carcinogenic and a mild skin irritant. The high alkalinity of borax (pH 9.5) is what causes skin irritation, which is the same reason that washing soda and even baking soda cause skin irritation, too. The alkaline pH of borax, washing soda and baking soda is what softens the water, and makes it possible for them to clean your clothes.
There are also several studies in the PubChem database that show borax is only a very mild lung irritant and causes no lasting damage. If ingested, it is quickly excreted in the urine. In addition, it does not really penetrate the skin well, and is not bio-accumulative.
Finally, the Material Safety Data Sheet lists borax as a health hazard of 1—the same as baking soda and salt. In other words, borax is toxic in the same way that salt is toxic (Actually ounce for ounce, salt is more toxic): A small amount can do great things; a huge amount will kill you and other living things.
You wouldn’t want to ingest large amounts of salt or baking soda, inhale them, or rub them in your eyes. Borax is no different.
Uses for Borax
Borax is used in laundry detergents, hair potions and skin lotions. Like diatomaceous earth, it also can help kill fleas and dust mites in your carpet by dehydrating them. It is also used as a safer ant and cockroach killer.
Borax is also naturally anti-fungal and anti-viral (but not anti-bacterial), and—here’s the neat part—through a chemical reaction with water, borax produces hydrogen peroxide (the main ingredient in OxyClean) to brighten and sanitize your clothes.
Because borax is made of just sodium, oxygen, hydrogen and boron, many people even ingest small amounts of borax mixed in water to self-treat various health conditions that supplemental boron can really help, like arthritis, fluoride detoxification, osteoporosis, prostate cancer, menopausal symptoms, psoriasis, and candida.
I do not recommend supplementing with borax because it’s very hard to regulate the dose, and you don’t want to overdo it. Use a high-quality boron supplement instead.
For external use, you should use the same precautions (gloves, dust mask or bandana) with borax that they would use around any dusty substance, like washing soda, bentonite clay, diatomaceous earth, or powdered soap. (Heck, even flour or powdered sugar would be irritating if inhaled!)
So, Is Borax Toxic?
In sum, borax is wholly natural and has no inherently toxic ingredients. It doesn’t cause cancer, accumulate in the body or in nature, or absorb through the skin.
Because the dose makes the poison, borax is not harmful to the body or the environment with normal, external usage any more than salt or baking soda is. In fact, the largest borax (borate) mine in the world—found in Boron, California—is considered to be one of the most ecologically sound and environmentally sustainable mines in the United States.
I consider borax a safe, effective cleaner, and I will continue to use it in my household green cleaning and safer pest control.