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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 The old collection of technical fact sheets will remain available in this archive, but they may contain out-of-date material.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.


  1. Boric Acid/Sodium Borate Salts: HED Chapter of the Tolerance Reassessment Elegibility Decision Document (TRED); U.S. Environmental Protection Agency, Office of Prevention, Pesticides, and Toxic Substances, Health Effects Division, U.S Government Printing Offices: Washington, DC, 2006.
  2. Draft Toxicological Profile for Boron; U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry: Atlanta, GA, 2007.
  3. WHO. Environmental Health Criteria 204: Boron; International Programme on Chemical Safety, World Health Organization: Geneva, Switzerland, 1998.
  4. Toxicological Review of Boron and Compounds in Support of Summary Information on the Integrated Risk Information System (IRIS); U.S Environmental Protection Agency, U.S. Government Printing Office: Washington, DC, 2004.
  5. Reregistration Eligibility Document: Boric acid and its sodium salts; U.S. Environmental Protection Agency, Office of Prevention, Pesticides, and Toxic Substances, Office of Pesticide Programs, U.S. Government Printing Office: Washington, DC, 1996.
  6. OMRI Generic Materials List; Organic Materials Review Institute, 2009.
  7. Rainey, C. J.; Nyquist, L. A.; Christensen, R. E.; Strong, P. L.; Culver, B. D.; Coughlin, J. R., Daily Boron Intake from the American Diet. J. Am. Diet. Assoc. 1999, 99 (3), 335-340.
  8. Hunt, C. D. Dietary Boron: Evidence for Essentiality and Homeostatic Control in Humans and Animals. Advances in Plant and Animal Boron Nutrition; Xu, F. Ed.; U.S. Department of Agriculture, Agricultural Research Center: Grand Forks, ND, 2007; pp 251-267.
  9. Habes, D.; Morakchi, S.; Aribi, N.; Farine, J.P.; Soltani, N. Soltani Boric acid toxicity to the German cockroach, Blatella germanica: Alterations in midgut structure, and acetocholinesterase and glutathione S-transferase activity. Pestic. Biochem. Physiol. 2005, 84 (1),17-24.
  10. Appel, A. G.; Gehret, M. J.; Tanley, M. J. Effects of Moisture on the Toxicity of Inorganic and Organic Insecticidal Dust Formulations to German Cockroaches (Blattodea: Blattellidae). J. Econ. Entomol. 2004, 97 (3), 1009-1016.
  11. Strong, P. L. Boric Acid and Inorganic Borate Pesticides. Handbook of Pesticide Toxicology, Volume 2: Agents, 2nd ed.; Krieger, R. I., Ed.; Academic Press: San Diego, CA, 2001; pp 1429-1437.
  12. Pfeifer, C. C., Hallman, L. F., Gersh, I. Boric acid ointment:A study of possible intoxication in the treatment of burns. J. Am. Med. Assoc. 1945, 128, 266-274.
  13. Weir, R. J.; Fisher, R. S. Toxicologic studies on borax and boric acid. Toxicol. Appl. Pharmacol. 1972, 23 (3), 351-364.
  14. Litovitz, T. L., Klein-Schwartz, W., Oderda, G. M., Schmitz, B. F. Clinical Manifestations of Toxicity in a Series of 784 Boric Acid Ingestions. Am. J. Emerg. Med. 1988, 6, 209-213.
  15. Welch, S. Boric Acid. Clinical Veterinary Toxicology; Plumlee, K. H., Ed.; Mosby, Inc.: St. Louis, MO, 2004; pp 143-145.
  16. Campbell, A.; Chapman, M. Borax. Handbook of Poisoning in Dogs and Cats; Blackwell Science: Oxford, London, 2000; pp 86-89.
  17. Reigart, J. R.; Roberts, J. R. Boric Acic and Borate. Recognition and Management of Pesticide Poisonings: Other Insecticides, 5th ed.; U. S. Environmental Protection Agency, Office of Pesticide Programs, U.S. Government Printing Office: Washington, DC, 1999; pp 75-76.
  18. Wong, L. C.; Heimbach, M. D.; Truscott, D. R.; Duncan, B. D. Boric Acid Poisoning: Report of 11 Cases. Canad. Med. Assoc. J. 1964, 90, 1018-1023.
  19. Baker, M. D.; Bogema, S. C. Ingestion of Boric Acid by Infants. Am. J. Emerg. Med. 1986, 4 (4), 358-361.
  20. Integrated Risk Information System (IRIS), Boron and Compounds; U.S. Environmental Protection Agency. http://www.epa.gov/iris/(accessed March 2010), updated Jan 2010.
  21. Linden, C. H.; Hall, A. H.; Kulig, K. W.; Rumack, B. H. Acute Ingestions of Boric Acid. Clin. Toxicol. 1986, 24 (4), 269-279.
  22. Endocrine Disruptor Screening Program; U.S. Environmental Protection Agency; Office of Prevention, Pesticides, and Toxic Substances, Office of Science Coordination and Policy. http://www.epa.gov/endo/pubs/regaspects/testorders.htm (accessed March 2010), updated March 2010.
  23. Barranco, W. T.; Eckhert, C. D. Boric acid inhibits human prostate cancer cell proliferation. Cancer Lett. 2004, 216 (1), 21-29.
  24. Meacham, S. L.; Elwell, K. E.; Ziegler, S.; Carper, S. W. Boric Acid Inhibits Cell Growth in Breast and Prostate Cancer Cell Lines. Advances in Plant and Animal Boron Nutrition; Xu, F., Ed.; U.S. Department of Agriculture, Agricultural Research Center: Grand Forks, ND: 2007; pp 299-306.
  25. Heindel, J. J.; Price, C. J.; Field, E. A.; Marr, M. C.; Myers, C. B.; Morrissey, R. E.; Schwetz, B. A. Developmental Toxicity of Boric Acid in Mice and Rats. Fundam. Appl. Toxicol. 1992, 18, 266-277.
  26. Heindel, J. J.; Price, C. J.; Schwetz, B. A. The Developmental Toxicity of Boric Acid in Mice, Rats, and Rabbits. Environ. Health Perspect. Supp. 7 1994, 102, 107-112.
  27. Price, C. J.; Strong, P. L.; Marr, M. C.; Myers, C. B.; Murray, F. J., Developmental 27. Toxicity NOAEL and Postnatal Recovery in Rats Fed Boric Acid during Gestation. Fundam. Appl. Toxicol. 1996, 32 (2), 179-193.
  28. Price, C. J.; Marr, M. C.; Myers, C. B.; Seely, J. C.; Heindel, J. J.; Schwetz, B. A. The Developmental Toxicity of Boric Acid in Rabbits. Fundam. Appl. Toxicol. 1996, 34, 176-187.
  29. Fail, P. A.; Chapin, R. E.; Price, C. J.; Heindel, J. J. General, reproductive, developmental, and endocrine toxicity of boronated compounds. Reprod. Toxicol. 1998, 12 (1), 1-18.
  30. Fail, P. A.; George, J. D.; Seely, J. C.; Grizzle, T. B.; Heindel, J. J. Reproductive Toxicity of Boric Acid in Swiss (CD-1) Mice: Assessment Using the Continuous Breeding Protocol. Fundam. Appl. Toxicol. 1991, 17, 225-239.
  31. Pahl, M. V.; Culver, B. D; Strong, P. L.; Murray, F. J.; Vaziri, N. D. The Effect of Pregnancy on Renal Clearance of Boron in Humans: A Study Based on Normal Dietary Intake of Boron. Toxicol. Sci. 2001, 60 (2), 252-256.
  32. Wester, R. C.; Hui, X.; Hartway, T.; Maibach, H. I.; et. al. In Vivo Percutaneous Absorption of Boric Acid, Borax and Disdium Octaborate Tetrahydrate in Humnas Compared to in Vitro Absorption in Human Skin from Infinate and Finite Doses. Toxicol. Sci. 1998, 45, 42-51.
  33. Vignec, A. J.; Ellis, R. Inabsorbability of Boric Acid in Infant Powder. AMA Am. J. Dis. Child. 1954, 88 (1), 72-80.
  34. Culver, B. D.; Shen, P. T.; Taylor, T. H.; Lee-Feldstein, A.; Anton-Culver, H.; Strong, P. L. The Relationship of Blood- and Urine-Boron to Boron Exposure in Borax-Workers and the Usefulness of Urine-Boron as an Exposure Marker. Environ. Health Perspect. Supp. 7 1994, 102, 133-137.
  35. Wilding, J. L.; Smith, W. J.; Yevich, P.; Sicks, M. E.; Ryan, S. G.; Punte, C. L. The Toxicity of Boron Oxide. Am. Ind. Hyg. Assoc. J. 1959, 20 (4), 284-289.
  36. Chapin, R. E.; Ku, W. W. The Reproductive Toxicity of Boric Acid. Environ. Health Perspect. Supp. 7 1994, 102, 87-91.
  37. Ku, W. W.; Chapin, R. E.; Moseman, R. F.; Brink, R. E.; Pierce, K. D.; Adams, K. Y. Tissue disposition of boron in male Fischer rats. Toxicol. Appl. Pharmacol. 1991, 111 (1), 145-151.
  38. Chapin, R. E.; Ku, W. W.; Kenney, M. A.; McCoy, H.; Gladen, B.; Wine, R. N.; Wilson, R.; Elwell, M. R. The Effects of Dietary Boron on Bone Strength in Rats. Fundam. Appl. Toxicol. 1997, 35 (2), 205-215.
  39. Emsley, J. The Elements; Oxford University Press, Inc.: New York, 1989.
  40. Schou, J. S.; Jansen, J. A.; Aggerbeck, B. Human Pharmacokinetics and Safety of Boric Acid. Arch. Toxicol. Supp. 1984, 7, 232-235.
  41. Vaziri, N. D.; Oveisi, F.; Culver, B. D.; Pahl, M. V.; Andersen, M. E.; Strong, P. L.; Murray, F. J. The Effect of Pregnancy on Renal Clearance of Boron in Rats Given Boric Acid Orally. Toxicol. Sci. 2001, 60 (2), 257-263.
  42. Butterwick, L.; de Oude, N.; Raymond, K. Safety assessment of boron in aquatic and terrestrial environments. Ecotoxicol. Environ. Saf. 1989, 17 (3), 339-371.
  43. Eisler, R. Boron Hazards to Fish, Wildlife and Invertebrates: A Synoptic Review; U. S. Fish and Wildlife Service Biological Report; Patuxent Wildlife Research Center: Laural MD, 1990; Vol. 85.
  44. Woods, W. G. An Introduction to Boron: History, Sources, Uses, and Chemistry. Environ. Health Perspect. Supp. 7 1994, 102, 5-11.
  45. Dordas, C.; Brown, P. H. Evidence for channel mediated transport of boric acid in squash (Cucurbita pepo). Plant Soil 2001, 235, 95-103.
  46. Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate, boric oxide (boric anhydride), sodium borate and sodium metaborate; exemptions from the requirement of a tolerance. Code of Federal Regulations, Part 180.1123, Title 40, 2003.
  47. Smith, G. J.; Anders, V. P. Toxic Effects of Boron on Mallard Reproduction. Environ. Toxicol. Chem. 1989, 8, 943-950.
  48. Hoffman, D. J.; Camardese, M. B.; Lecaptain, L. J.; Pendleton, G. W. 48. Effects of Boron on Growth and Physiology in Mallard Ducklings. Environ. Toxicol. Chem. 1990, 9, 335-346.
  49. Zhang, Y. C., Perzanowski, M. S.; Chew, G. L. Sub-lethal exposure of cockroaches to boric acid pesticide contributes to increased Bla g 2 excretion. Allergy 2005, 60, 965-968.
  50. Regulatory Determinations Support Document for Selected Contaminants from the Second Drinking Water Comntaminant Candidate List (CCL2); U.S. Environmental Protection Agency, Office of Ground Water and Drinking Water, U.S. Government Printing Office: Washington, DC, 2008.
  51. ACGIH. TLVs and BEIs, Based on the Documentation of the Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices; American Conference of Governmental Industrial Hygienists Worldwide: Cincinnati, 2008; p 14.
  52. CDC. NIOSH Pocket Guide to Chemical Hazards: Borates; U.S. Department of Health and Human Services, Centers for Disease Control and Prevention: Atlanta, GA, 2007; p 30.
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