Last Updated on August 25, 2022 by The Filtery Staff

Ah, borax. What once was a household name, is once again, a household name – thank you DIY slime! What you may not know about borax is that it is also used as a laundry booster, flea killer, and a “green cleaner,” and it’s been around since the late 19th century. 

Like most products in our society today, borax garners a lot of questions about its toxicity levels. Making one wonder… Is borax really safe to use? And what are the possible dangers of using borax? Are we to believe the companies like 20 Mule Team Borax when they state that borax is safe and all natural? 

Or is it a case of greenwashing? We set out to find out the truth on borax! Is it safe? And if borax is safe to use, then why was it banned in the U.K.?

Let’s take a look at this enduring, yet highly controversial substance and find out if borax is dangerous or toxic to you or your pets.

What Is Borax?

Borax is a water-soluble alkaline mineral salt. It’s white and powdery, with a baking soda like consistency. (Drop a box of this stuff and you’ll be saying some choice words!)You can find it sold in stores in the U.S. in a box in the laundry section. Borax is most well-known as a natural, powerful cleaning agent. People love it so much it has garnered many nicknames like “White Gold” and “The Magic Crystal.” It was INSANELY popular in the late 19th century, and early to mid-late 20th century.

You will also find borax used as an additive in several common household products hidden under chemical compound names; you’ll find it referred to as sodium borate, sodium tetraborate, and disodium tetraborate, which is a naturally occurring mineral. 

Not to be left out, sodium tetraborate decahydrate is the name for borax under the International Union of Pure and Applied Chemistry (IUPAC). Because we needed a fourth name for it—thank you, chemists!

Where Does Borax Come From?

Borax is most commonly mined from ephemeral lakes, which are lake beds that are flooded for short periods of time and then dry up. It is considered an evaporite, which means it was formed through the process of concentrating and crystallizing the mineral sediment when the water evaporates.

The U.S. Borax supply mostly comes from Death Valley and has been a staple for over 145 years in the U.S. Yet, the first known deposits are credited as coming from Tibet where the substance has been used for over 4,000 years.

What Is The Difference Between Borax And Boric Acid?

The easiest way to explain this is that boric acid is actually made out of borax. Both contain boron, an element found in food and the environment. 

Boric acid is made by dissolving borax into boiling water and adding an acid, such as hydrochloric acid, then allowing it to cool. Once the solution cools, boric acid crystals form and—viola!—boric acid. 

Borax is highly alkaline and contains sodium, which is what lends itself to softening water and helping to remove acidic based stains like mustard. 

Are Borax And Boric Acid Synthetic?

Borax rock/crystal is mined directly from the earth. The compound can then be processed into boric acid among a myriad of borates for other products.

Borax deposits are more abundant than naturally occurring boric acid. Though not common, boron within the borax can react with naturally occurring sulfur in the ground, especially near volcanic deposits, and form into boric acid.

Although it can be produced synthetically using boron compounds, this is not the standard operating procedure and it’s unnecessary because of it’s renewability rate. Borax is considered “natural,” but that doesn’t necessarily make it “green” according to its detractors.

why is borax banned in uk

Why Is Borax Becoming Popular Again?

When homemade slime became all the rage, a box of borax was sure to be in every home that had slime-making munchkins.  

Many families were left with partially used boxes of borax and wondering what to do with it. Also, the green cleaning movement started picking up momentum; the use of borax as a laundry additive as well as a mainstay for homemade cleaning products started to catch on again.

What Is Borax Most Commonly Used For?

Borax seems to be a cleaning “catch-all,” right up there with the non-contested “green” cleaners such as vinegar, lemon, and baking soda. But it is also very good at buffering pH levels and preventing or slowing bacterial or fungal growth, among many other uses.

Some of the most common household uses for borax:

  • Laundry Booster/Stain Remover
  • Killing Mold On Drywall
  • Garbage Disposal Cleaner
  • Kills Ants And Dehydrates Fleas*
  • Cleaner/Disinfectant/Deodorizer

Some uncommonly common uses for borax:

Some common but uncommonly known uses for borax:

  • Chinese Rice Noodles And Rice Dumplings
  • Putting Out Grease Fires
  • Used In Denture Adhesives
  • Cosmetics To Inhibit Bacterial Growth
  • Lotion And Bath Products

*Borax, again used interchangeably with boric acid, are both well known and used as insecticide.

Did Borax Become Unpopular Because It Is Dangerous? 

Borax was considered a laundry staple for over 50+ years. Back in the day, laundry powders were made up of soap, not surfactants, which tended to leave a soapy film on clothing, especially in hard water. The alkalinity and hydrogen action of borax helped to remove stains, odors, and soften the water in order to rinse away soap film and leave clothes cleaner and fresher.

By the 1980’s, with the continued improvements and new formulations, as well as the introduction of liquid detergents, the use of borax started to decline quite a bit. By the ’90s, borax had outlived its heyday as the up-and-coming generation seemed to have skipped adding it to their laundry altogether.

Is Borax A Green Product? 

Usually, borax is labeled as a green product because it doesn’t contain chlorine or phosphates. However, according to the Environmental Working Group (EWG), the answer is no. This EWG article, written in 2011, seems to create more questions than answers with some of the supporting links being defunct. 

The Green Built Alliance offers a pretty well-rounded checklist that you can refer to that may help you to determine if a product is truly “green.” When it comes to whether or not borax is “green,” the answer is, unfortunately, unclear.

On the plus side, borax is considered sustainable/renewable even though millions of tons of borates are mined each year. Twice that amount is redistributed by condensation, rain, volcanic, and other atmospheric activities.

Why Do Some Say Borax Is Toxic?

The EWG, along with other sources, state concerns about toxicity through skin absorption and that borax is a skin irritant. 

In the Library of National Medicine, a comparative study that goes as far back as 1998 showed that the toxicity levels of borates, boric acid, and borax, through intact human skin is low and, “the use of gloves to prevent systemic uptake is unnecessary.”  

According to this review, however, it can be an irritant for the eyes, and yes, it is extremely important not to inhale this powdery substance which is clearly stated on the label. Use of borax is indeed worthy of caution (just as with almost any cleaning substance).

is borax toxic

Is Borax Safe?

It all comes down to who you ask and who paid for the study. Surprise?! Not really. 

To be honest, it’s quite difficult to find a definitive answer and it seems to depend on how the material/data is presented. Based on the information available, it can be easily influenced by the author’s personal desire to stop or keep using borax.

When looking at it from a consumer’s point of view, if you go in with the mindset that borax is dangerous, you’re sure to find enough information to support your belief. The same thing happens if your mindset is that borax is safe. 

The important thing is to start your research with an open mind, look into opposing views, check the science, and be objective. Take what you’ve learned and decide if you feel borax is safe for the uses you intend for yourself, your family, and your pets. Don’t forget the borax police won’t come to your home one way or the other!

Is Borax Dangerous? Borax Is Not Classified As A Carcinogenic

There’s no controversy on this fact: Borax, sodium tetraborate, is inorganic and not classifiable as a human carcinogen. As stated in section 14.1.2 Evidence for Carcinogenicity, compound summary for sodium tetraborate, NIH. So on the issue of cancer, there is no reason to worry.

Is Borax Toxic To People?

No matter where you look, whether at studies or anecdotal opinions, borax is not toxic with the common disclaimer: “unless it is ingested. However, according to the Material Safety Data Sheet, Section 11: Toxicological Information: ingestion and skin/dermal rank low acute toxicity LD50. 

Equally customary, but important, is the warning that exposure to borax can irritate the eyes and the skin, although study after study has determined that the level of toxicity through the skin is low to not at all, as long as the skin is not broken. 

Toddlers, young children, and even pets can be at special risk from hand-to-mouth (or paw to mouth?) ingestion of borax dust used on carpets or along walls for pest control. 

When the EWG notes “poison reports suggest misuse of borax-based pesticides,” it then lists out the acute toxicity symptoms (for ingesting large quantities of borax): nausea, vomiting, skin rash, eye irritation, oral irritation and respiratory effects. However, borax is ranked as “low acute toxicity” as previously discussed.

is borax safe for pets

How Can Borax Hurt My Pet?

You don’t want your pet rolling around in borax or eating the stuff. And please don’t put it on their skin as it is very alkaline and therefore can cause heightened irritation (especially if they are scratching and biting at fleas since the skin is likely abraded or broken).

If you decide to use boric acid (not borax) as a pesticide, keep in mind this particularly common sense quote regarding boric acid: “Because it’s a pesticide, it’s intended to kill something. All pesticides have some level of toxicity,” this is from Alicia Leytem, a pesticide specialist at Oregon State University’s National Pesticide Information Center.

If you choose a DIY remedy, be sure to know and understand the usage. According to PetMD, most people use more than is needed which can result in overexposure to you and your pet. Following the directions from EPA-registered boric acid products are the way to ensure you don’t hurt your pet.

Why is Borax banned in the U.K. and E.U.? What Is All The Controversy? 

In December of 2010, the E.U. reclassified the ‘Borate’ group of chemicals that borax belongs to as a Substance Of Very High Concern (SVHC) due to its potential to be hazardous to reproductive health. The decision to classify the Borate group as an SVHC came after a series of studies were conducted on rats and mice who were force-fed obscene amounts of boric acid. These studies indicated that boric acid, not borax, was reprotoxic. 

The Material Safety Data Sheet (MSDS) also noted that the exposure conditions of the animals were in doses many times in excess of conditions that could occur through inhalation of dust in a work environment or product use. And the kicker…the MSDS also says that a study on humans who work and have long-term exposure to sodium borate and boric acid dusts showed no adverse effect on fertility. 

Even with this data available, any substances or compounds imported into the E.U. which contain borax or borates are now required to be labeled with warnings regarding fertility and the possibility of harming unborn children. Borax as a cleaning and laundry product is no longer available to purchase in stores in the E.U., you can only buy “Borax Substitute”.  

Sadly (and you can make up your own mind), there are many conspiracy theories as to why this centuries old substance suddenly became “toxic” to women and unborn children. If you like a challenge, look up Rex Newnham, Ph.D., D.O., N.D. If you don’t have time to look it up right now, Dr. Newnham found that boron, in the form of borax, is actually essential for healthy bone and joint function and he proposed that it can actually help to cure arthritis. (This is what got him in some pretty big trouble with the pharmaceutical companies and the government.)

Coincidentally, borax was banned in Australia in 1981 when they instituted a regulation that declared boron* and its compounds to be poisons in any concentration. This was after a pharmaceutical company was approached to market and distribute a boron based tablet for arthritis. 

*”The trace mineral boron is a micronutrient with diverse and vitally important roles in metabolism that render it necessary for plant, animal, and human health, and as recent research suggests, possibly for the evolution of life on Earth” Pizzorno L. Nothing Boring About Boron. Integr Med (Encinitas). 2015;14(4):35-48.

Borax Considered Reprotoxic By Some Countries

As mentioned several times within this article, the name borax and boric acid are typically used interchangeably, which isn’t surprising since they are almost impossible to tell apart side by side. The studies that claim toxicity in regard to reproductive concerns are testing boric acid in amounts so large, they concede a human would not likely be exposed to such an amount. 

Sodium tetraborate is less toxic than NaHCO3 (baking soda) or NaCl (table salt) when ingested in the same amounts: mg/kg. In other words: if you ate a large amount of baking soda or table salt, these substances are more toxic, respectively, than the same amount of borax. The LD50 (Lethal Dose, expressed in mg/kg of body weight, is the amount of an ingested substance that kills 50% of the test sample.)

  • The Lethal Dose of Baking Soda is 4200mg/kg
  • The Lethal Dose of Table Salt is 3000mg/kg
  • The Lethal Dose of Borax is 2660mg/kg

Am I saying you can or should eat borax? NO. No one is in any way suggesting any such thing. This is simply pointing out that any substance can become toxic at a certain level (even water if too much is consumed!).

What is “Borax Substitute?”

In the E.U., since the ban on borax, either you try to find it online or you use the borax substitute known as Sodium Sesquicarbonate, which is sodium carbonate plus sodium bicarbonate. The EWG gives sodium sesquicarbonate as a cleaning compound an A+ rating, indicating its safety.

Here’s a mind bender: check out PubChem and look at sodium sesquicarbonate (“Borax Substitute”) Antidote and Emergency Treatment, then compare it to sodium tetraborate (borax) First Aid Measures. These resources tell a story: for “borax,” the treatment involves “basic first aid,” whereas for “Borax Substitute,” treatment requires “antidotes and emergency treatment.” Furthermore, any large ingested dose will require immediate medical attention for both substances! So the question becomes: is “Borax Substitute” really any safer than borax itself?

is borax dangerous

Is Borax Considered Safe To Use In The United States?

For a super long time now, sodium borate and boric acid have been used as antiseptics, irrigants, buffers, dressings, and preservatives in medicine. Both compounds were reviewed by several FDA over-the-counter (OTC) drug panels. These compounds have even been deemed safe and effective for preservatives in vaginal products.

Contrary to many online sources, and through research of studies and documentation in the NIH and actual MSDS (as cited previously in this article), there are few conclusions that we can feel comfortable about. The research shows that borax does not absorb through the skin, accumulate in body tissues, or cause cancer.  

It’s totally natural, usually considered 99.9% pure from the mine in Boron, California. As far as a cleaner, is borax safe? This is something you will still have to determine for yourself.

Borax Banned As A Food Additive In The U.S.

As early as the 1870s, people were adding boric acid and borax to food. This was to help preserve food and to inhibit mold and bacteria and was often used as a glaze to keep flies off of meats. (Sounds delish, right?) 

Borax is still used in other countries (not all legally) in noodles, meatballs, rice dumplings, fried fritters, and other foods to improve shelf-life, increase elasticity in noodles, and crispness of fried foods.  

Most countries stopped using borates due to their purported toxicities and in some cases, abuse. Ingesting borax in large quantities is just as detrimental as eating too much table salt or baking soda, which is why it is not used as an additive in the U.S. any longer… But don’t you find it interesting that it was actually used as a food additive? 

So, is borax poisonous? Interestingly, while the E.U. won’t let you clean with borax anymore, they certainly want their caviar preserved with it! Even three years after they banned it, the European Food Safety Authority (EFSA) was still approving borax and boric acid for sturgeons eggs! If you want to check it out, at least five “European acronyms” are in the report citing eight different tests/reviews that as an additive, it was approved over the course of the past 33 years.  

Conclusion: Sooo… Is Borax Safe Or Not?

Borax has been around for ages and has significant historical uses in medicine, agriculture, ceramic glaze, food preservation, and precious metal workings. The Babylonians got it from the Himalayas for jewelry, the Egyptians used it for mummification, and Marco Polo is credited for transporting it to Europe in the 13th century. 

Here we are in the 21st century faced with the controversial topic: is borax safe? 

As with almost any substance, improper usage and excessive exposure can create adverse symptoms for a human or an animal and borax is not any different. Vinegar is “green,” yet if I got it in my eye it would certainly cause irritation!  

Whether anecdotal or in studies, the data all seem to conclude with “may cause reproductive toxicity” when ingested in abnormally high doses by rats and mice. There are no known human reproductive impacts at this time.  

Why the U.K. and the E.U. banned borax seems pretty straightforward at first glance. The contention is in the truth about whether borax is truly any more toxic than table salt or baking soda.

The good news: here in the U.S., we have the freedom to not only continue to dig for answers but also to walk into a store and purchase Borax if we so choose. Ultimately, you’ll have to make that decision as to what feels right for you and your family. 

About the Author

With expertise in all things WordPress, coding, SEO, and more, the Blog Posts to Go team provides busy bloggers with targeted, high-quality keyword research, article outlines, competitor research, and more. Not only that but the duo behind BPTG is passionate about non-toxic living and is on a journey to reduce harmful chemicals from their homes for the overall health of their families.


Image Credits: Twenty Mule Team, cottonbro, Polina Tankilevitch, Charles Deluvio, HowToGym