Frequently Asked Questions

With the applications, benefits, and uses of boron, borates, and 20 Mule Team® Borax products spanning a dozen industries and scores of products, questions are only natural. Here, you’ll find answers to some of the queries we hear most often.

Don’t see your question below? Contact us.

Boron/Borate Chemistry and Research

Boron/Borate Usage and Safety

U.S. Borax Company and History

U.S. Borax Products and Customers

General/Consumer Questions

Boron/Borate Chemistry and Research

What is boron?
Boron on the periodic table Boron is a nonmetallic chemical element symbolized as B on the periodic table. It has the atomic number 5. It only occurs naturally in compounds called borate minerals—deposits of which are found in the Earth's crust. Boron is primarily used in chemical compounds including boric acid, borax, and boric oxide.
Is boron a liquid?
Boron is a solid and is classified as a metalloid element (has properties of both metals and non-metals). Elemental boron is never found free in nature. It occurs naturally in minerals that contain boron and oxygen.
What are boric acid's chemical properties?
Boric acid is found abundantly in nature, especially in volcanic areas, such as Italian hot springs. Boric acid’s chemical formula is H3BO3. It is a weak monobasic acid. It dissolves in boiling water and forms metaboric acid when heated to temperatures higher than 170°C. U.S. Borax sells boric acid under the brand name Optibor®.
What are some other names for borax?
Borax is also known as sodium borate, sodium tetraborate, and disodium tetraborate.
How can I acquire lab samples of U.S. Borax products?
To request a U.S. Borax product sample, please fill out our sample request form.
I am an agronomist or agricultural consultant looking for information on the use of boron or borates for crop health. Can you help me?
Yes, we have a wealth of information on the agriculture uses of boron at: https://agriculture.borax.com. Please contact our global agriculture team members with your questions.

Boron/Borate Usage

What are some boron oxide uses?

Boron oxide is used in the following applications:

Does fiberglass contain boron?

Not all fiberglass contains boron, but most of it does. Boron is added to fiberglass to increase its strength. For more information, read Boric Oxide for Insulation Fiberglass.

What are the benefits of boron in laundry detergent?

Borates in laundry detergent help:

  • Improve cleaning action
  • Prevent dirt from redepositing on clothes
  • Control pH
  • Safely and effectively bleach stains

For more information, read Boron in Cleaners and Detergents.

Is boron toxic?
Scientists conduct studies to determine both the level at which boron is harmful and the level at which boron is beneficial to health. Laboratory animals that ingested high doses of borates over long periods have shown adverse developmental and reproductive effects. In studies where boron is completely removed from the diet and environment, similar adverse effects occur.

In other words, too little boron is as bad as too much. 
What do studies of populations or workers exposed to high levels of borates show?
No evidence of adverse reproductive effects attributable to boron have been observed in epidemiological studies of borate workers and populations with high exposures to boron. Learn more about the safe handling of borates.
What would happen if you accidentally ingested a very high dose of borates?
An extremely high intake of borates would make most people vomit. But it is nearly impossible to be exposed to such quantities through eating foods or using products that contain borates. We’ve been mining and refining borates for more than 140 years. Evaluation of our workers—who are exposed to higher levels of borates than most people—have shown no adverse developmental or reproductive effects. In most instances where people have experienced artificially high borate intake, vomiting or excretion in urine has been rapid, and blood and tissue concentrations were quickly back to normal.

U.S. Borax Company and History

How long has U.S. Borax been in business?
In 1872, borate deposits were discovered in California’s Death Valley. Several companies sprung up in the region to mine borates. By 1890, they were mostly consolidated into the Pacific Coast Borax Company. In 1956, the Pacific Borax Company merged with the United States Potash Corporation to form U.S. Borax.

Learn more about the history of U.S. Borax.
Is U.S. Borax an independent company?
Rio Tinto logoU.S. Borax was acquired by Rio Tinto in 1967. The new group, sometimes referred to as Rio Tinto Borax or Rio Tinto Borates, is a wholly owned subsidiary of Rio Tinto Group.
Is U.S. Borax ISO certified?
All of our sites are certified to ISO 9001:2008 Quality Management Systems standards.
Where do you get the borates you use in your products?
Boron operations mine and facilityWe operate California’s largest open pit mine in Boron, California.
Can I visit the U.S. Borax mine?
Borax Visitor CenterThe mine in Boron, California is closed to the general public. But, the Borax Visitor Center is open (and free to visit), seven days a week, excluding major U.S. holidays. Learn more about the Borax Visitor Center and plan your visit.
Can I buy products directly from U.S. Borax?
U.S. Borax produces and sells bulk borates; we do not sell any consumer borate products.

To buy our borate products in bulk, please contact your local sales representative for more information about purchasing our industrial and agriculture products through us or one of our distributors.
What does U.S. Borax do to protect people from possible risk?
All our operations comply with all applicable safety regulations and make safety training a priority. Learn more about our commitment to keep our workplaces safe.
Are you hiring? Where can I apply to work for U.S. Borax?
As a division of Rio Tinto, U.S. Borax has a number of positions if you are looking for a career that makes a difference. Learn more about joining the U.S. Borax team.

U.S. Borax Products and Customers

Where can I buy borax?
U.S. Borax produces and sells bulk borates. To buy large quantities of borax, please contact your local sales representative

If you are looking for borax for home use, the Dial Corporation acquired U.S. Borax’s consumer products division in 1988, and they were subsequently acquired by Henkel. They produce and distribute the 20 Mule Team® Borax products sold in stores. Visit their web site at www.20muleteamlaundry.com
Where can I get material safety data sheets or handling information for your products?
You can find information about safety and handling in the following places: Or send us an email at rtb.sds@riotinto.com and tell us which product you’re using.
Can you send me copies of your product labels?
To request product labels, please contact your sales representative or customer service representative for more information.
What U.S. Food & Drug Administration (FDA) approvals do you have for your products?
Read our Statement on FDA Status of Borates. Or, send us an email at rtbproduct.stewardship@riotinto.com with details about your needs.
Where can I get boron cleaning products?
20 Mule Team Laundry Booster boxBoron can be found in a number of cleaning supplies available to the general public. One of the most recognizable is 20 Mule Team® Borax Laundry Booster which is sold by Henkel. Find out where you can buy 20 Mule Team Borax Laundry Booster.
Where can I find consumer products such as 20 Mule Team Borax Laundry Booster?
The Dial Corporation acquired U.S. Borax’s consumer products division in 1988. Subsequently, Henkel acquired Dial in 2003 and can help you find these items in your area. Or, visit their website at: www.20muleteamlaundry.com
Where can I find industrial cleaning products such as Boraxo Hand Soap?
Henkel manufactures and distributes these products as Dial Professional and can help you find them in your area. You can visit their website at: www.dialprofessional.com
Can you help me register my borate-based product with the U.S. Environmental Protection Agency (EPA)?
Send us an email at rtbproduct.stewardship@riotinto.com with details about your needs and interests. Or, read more about our Product Stewardship team.
How do you test your products for accurate boron content?
Beaker at the Quality LabWe use titration to measure wt.% of B2O3 at our Quality Lab in Boron, California. There, our experts routinely test U.S. Borax borate products. Learn more about our boron testing methods.
Do you have experts that can help with my formulations?
Yes. We have a number of specialists around the globe that can answer your boron formulation and agriculture trial questions. Learn more about our technical support experts.
What if something is wrong with my shipment?
In the Americas:
  • For non-emergencies, contact Customer Service at (800) USBORAX (800-872-6729)
  • For emergencies, dial (800) 228-5635, extension 144
For all other regions, visit our customer service page to find your local representative.

General/Consumer Questions

Is borax or boric acid safe for home use, including crafts, food preservation, and personal care? What should I know about diverting water wash to my garden?
Read more in our Product Stewardship section. Or, email us at rtbproduct.stewardship@riotinto.com with your specific application and information needs.
Can I use borates for flea control or food preservatives?

U.S. Borax’s products are not intended for use in food applications and are labeled accordingly. Therefore, our borate products shall not be used as (or to manufacture) food additives or preservatives. Read our Statement on FDA Status of Borates.

U.S. Borax does not sell any product into the borate/borax flea control or carpet application businesses. In keeping with our product stewardship commitment to our customers, we recommend against the use of borate products for carpet applications. These applications include boric acid, borax, or other borate-containing products intended for use on carpets as deodorizers or flea control agents.

These carpet-use patterns are different from all other borate product uses in that they present the opportunity for small children or pets to ingest borates directly from the carpets. It is not feasible to assess the extent of exposure to children and pets under all possible scenarios, due to the variety of parameters that determine exposure from carpets (eg variation in carpet type, borate product type, application method and rate, vacuum efficiency and frequency, and individual behavioral patterns of children or pets). Without adequate exposure information, U.S. Borax cannot determine the level of risk that may result from carpet-use patterns; therefore, we do not support the use of borate products for carpet flea control applications by anyone, especially consumers.

It should also be recognized that any compound used for the purpose of mitigating “pests” is considered to be a “pesticide” which is regulated by state and federal authorities (U.S. Environmental Protection Agency). Learn more:

Can I use borates as flame retardants, wood preservatives, insect/pest control, or agricultural end uses?
Read more at borate function by application. Or, visit our related applications pages: If this still doesn't answer your question, send an email with details about your needs and interests to: rtbproduct.stewardship@riotinto.com.
Do you still make 20 Mule Team hobby kits?
These model kits originated as a promotional program for 20 Mule Team Borax in 1954. Unfortunately, they have been discontinued.
How much is my historic U.S. Borax artifact worth?
While we’re proud of our heritage, we do not maintain records of the value of U.S. Borax posters, model kits, advertising, photography or other memorabilia.

Learn more about U.S. Borax history.
Any other questions? Please contact us at usborax@riotinto.com

U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 500 customers with more than 1,700 delivery locations globally. We supply 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles east of Los Angeles.  Learn more about Rio Tinto

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