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Boric Acid

Technical Fact Sheet

As of 2011, NPIC stopped creating technical pesticide fact sheets. The old collection of technical fact sheets will remain available in this archive, but they may contain out-of-date material. NPIC no longer has the capacity to consistently update them. To visit our general fact sheets, click here. For up-to-date technical fact sheets, please visit the Environmental Protection Agency’s webpage.

Laboratory Testing: Before pesticides are registered by the U.S. EPA, they must undergo laboratory testing for short-term (acute) and long-term (chronic) health effects. Laboratory animals are purposely given high enough doses to cause toxic effects. These tests help scientists judge how these chemicals might affect humans, domestic animals, and wildlife in cases of overexposure.

Molecular Structure -
Boric Acid

Chemical Class and Type:


Physical / Chemical Properties:

Active Ingredient CASRN Molecular Formula % Boron Physical State Vapor Pressure (Torr) Molecular Weight Solubility in Water (% w/w 20 °C) Octanol Water Coefficient (Kow)
Boric Acid 10043-35-3
H3BO3 17.48% White or colorless solid crystalline powder <10-4 at 20 °C 61.83 4.72% 0.175
Sodium tetraborate decahydrate (borax) 1303-96-4
10 H20
11.34% White or colorless crystalline powder <10-6 381.43 4.71% 0.175
Sodium tetraborate pentahydrate 11130-12-04
5 H20
14.85% mild white alkaline salt <10-6 291.35 3.6% No data
Sodium tetraborate anhydrous 1330-43-4
Na2B4O7 21.5% Solid crystalline or amorphous <10-6 201.22 24.8% No data
Disodium octaborate tetrahydrate 12008-41-2
4 H20
20.96% Powder <10-6 412.31 9.5% at 20 °C No data
Disodium octaborate (anhydrous) 12008-41-2
Na2B8O13 25.83% Solid rods <10-6 340.31 No data
Sodium metaborate 15293-77-3
NaBO2 Solid white pieces or powder <10-6 65.82 Soluble, no values reported No data

Mode of Action:

Target Organisms

Non-target Organisms

Acute Toxicity:




Signs of Toxicity - Animals

Signs of Toxicity - Humans

Chronic Toxicity:



Endocrine Disruption:




Cancer: Government agencies in the United States and abroad have developed programs to evaluate the potential for a chemical to cause cancer. Testing guidelines and classification systems vary. To learn more about the meaning of various cancer classification descriptors listed in this fact sheet, please visit the appropriate reference, or call NPIC.

Developmental Effects:



Reproductive Effects:



Fate in the Body:





Medical Tests and Monitoring:

Environmental Fate:






Food Residue

Ecotoxicity Studies:


Fish and Aquatic Life

Terrestrial Invertebrates

Regulatory Guidelines:

Date Reviewed: May 2012

Please cite as: Harper, B.; Gervais, J. A.; Buhl, K.; Stone, D. 2012. Boric Acid Technical Fact Sheet; National Pesticide Information Center, Oregon State University Extension Services. http://npic.orst.edu/factsheets/archive/borictech.html.


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