Boric acid Chemical Properties
- 9.2(at 25℃)
- Clear, dark blue
- EPA Substance Registry System
- Boric acid (11113-50-1)
Boric acid Usage And Synthesis
Boron (B), the fifth element in the periodic chart, is ubiquitous in the environment, where it is found combined with O to form compounds called inorganic borates (e.g., borax). Natural sources of borates in the environment include soils, rocks, surface and ocean waters, and the atmosphere.
B in the form of borates has long been recognized as an essential plant micronutrient for the growth and viability of plants. Recently, there has been a growing body of evidence that B may be an essential element for frogs, fish, rats, and humans, as well as for plants[1-5]. The major sources of B exposure are diet and drinking water. Fruits, vegetables, and nuts are especially rich in B. Rainey et al. recently studied daily dietary B intake, evaluating the food consumption records of over 25,000 Americans over several days. The median, mean, and 95 percentile B intake for all participants were 0.76, 0.93, and 2.4 mg B/d, respectively.
Boric acid (H3BO3) is a boron compound that is soluble and circulates in plasma. It is a colorless, water-soluble, salt-like white powder, which have been used as pesticide since 1948. Normally, it is used to kill mites, insects, fungi and algae. For instances fleas, cockroaches, termites and wood decay fungi[8, 9]. Borate chemicals and boric acid have been used extensively for industrial purposes and its salts have been used for medication as an antiseptic to kill bacteria and fungi. Normally, it is used in the form of powder and liquid; depending to the target and conditions of pest, boric acid might applied as a spray or aerosol, as well as in the form of tablets, granule, pellets, paste or crystalline.
Boric acid plays a role as a “stomach poison” for certain pest such as cockroaches, ants and termites. As an insecticide, it usually applied in bait form or used as a dry powder in which containing a feeding attractant and then added into crevices and creaks so that it forms a layer of dust. So boric acid adheres to their legs when the insects move across the powder. Hence, they may ingest the poison when the insects groom themselves. This will causes death due to starvation and dehydration after 3-10 days. However, the insecticide mechanism of boric acid on insects has not been satisfactorily developed. Some hypotheses has been suggested including death by starvation owing to abrasive effect on the cuticle then cause destruction or slow drying of foregut cells[12, 13].
Besides that, when boric acid used as an herbicide, it desiccates or disrupts the photosynthesis system in plants. Hence, boric acid is normally used to suppress algae in swimming pools and sewage systems. On the other hand, as a fungicide, the fungicidal properties of boric acid prevent the production of conidia or asexual spores of the fungi; hence, it suppresses the growth of fungi. Therefore, boric acid is used as wood preservative in wood industry such as lumber and timber products that controls decay producing fungi[9,14].
Boric acid is reported to be used as food preservatives in some foods and food products. Boric acid is used for preserving meats, meat products, caviar and dairy products. This is because boric acid is able to inhibit the growth of microorganism, therefore, the preserved food can stay fresh and longer. Moreover, according to Yiu et al. (2008), boric acid was added to some food products to control starch gelatinization, as well as enhance the color, texture and flavor of the food.
BA given orally is readily and completely absorbed in humans and animals. In adult human volunteers, Schou et al. found 94% of a single oral dose of 500 mg BA (131 mg B) was excreted via the urine. Jansen et al. evaluated the absorption of a single aqueous dose of 750 mg of BA in a group of six male volunteers; more than 92% of the BA was excreted in the urine. A similar degree of oral absorption based on urinary excretion of B was observed in volunteers drinking curative spa waters with a high B content, providing a daily dose of approx 100 mg B for 2 wk. There is negligible absorption of BA across intact skin in humans and animals. Maibach reported minimal dermal absorption of BA in human volunteers. Earlier studies showed little evidence of dermal absorption in human infants and adults. Dermal absorption across non-intact skin varied with the vehicle used; greater absorption was observed with aqueous-based vehicles compared to oil-based vehicles (e.g., ointments). Only traces of boric acid in ointment penetrated the skin of infants with moderate diaper rash.
BA is distributed similarly in humans and animals. It is rapidly distributed throughout body water. After administration of BA, B levels in soft tissues are equivalent to those found in plasma, whereas bone B levels appear to be higher than those found in plasma or soft tissues. In humans, a greater concentration of B in bone was reported relative to other tissues. Bone B concentrations were determined on 116 ashed samples from 33 human cadavers[25, 26]. More recently, Ward examined B concentrations using a more sophisticated neutron activation analytical technique in a variety of human tissues, including bone, from 14 normal individuals and 18 individuals with rheumatoid arthritis. High B levels were found in bone, hair, and teeth.
BA is not metabolized in humans or animals. The metabolism of BA by biological systems is not possible owing to the high energy requirements (523 kJ/mol) needed to break the B----O bond. In both humans and animals, BA is excreted unchanged in the urine regardless of the route of administration. It is rapidly excreted, with a half-life of < 24 h in humans and animals. BA is slowly eliminated from bone.
In humans, 99% of a single iv dose of BA was excreted in the urine, and the half-life was estimated to be 21 h, based on a three-compartment pharmacokinetic model. In another study by the same investigators, 94% of an oral dose of BA (aqueous solution) was recovered in the urine of a group of male volunteers, and more than 50% of the oral dose was eliminated in the first 24 h, consistent with the 21-h half-life in the iv study.
Because of boric acid contains cumulative toxicity, FAO/WHO Expert Committee declared that boric acid is unsafe to use as food additives. Even though Ministry of Health Malaysia does not allow boric acid to be used as a food additive, however, it has been reported in some of the local foods in Malaysia such as yellow noodle and fish ball. Moreover, boric acid is harmful to human health if consumed in higher amount. However, due to unawareness of the risk of boric acid, it is continued to be used in the production of food especially noodles and some processed seafood such as fish ball. Boric acid normally used for preservation of food products. It can cause to health problem if the food containing boric acid was ingested by human as boric acid and borates are toxic to cell. Hence, it is deleterious to health and its usage is not recommended. For new-born baby, the possible lethal doses are in between 3-6 g, whereas 15-20 g total for adults. The common symptoms from several incidents of boric acid poisoning included coughing, eye irritation, vomiting and oral irritation. However, the toxicity mechanisms of boron compound remain unclear (Kot, 2009). According to Moseman (1994), the usual amount of boron in urine, blood and soft tissues, normally in the range below 0.05 mg kg−1 and do not above 10 mg kg−1. Some boric acid poisoning cases reported that as high as 2 g kg−1 boric acid was found in liver tissue and brain[34, 35].
Boric acid (boracic acid; H3BO3) is used for the manufacture of glass, welding, mattress batting, cotton textiles, and a weak eyewash solution.
Boric acid (H3BO3) is a solid, soft, smooth, solid weak acid that is used in pharmaceutical and cosmetic industries.
- W. G. Woods, An introduction to boron: history, sources, uses and chemistry, Environ. Health Perspect. 102(7), 5--11 (1994).
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- F. H. Nielsen, The saga of boron in food: from a banished food preservative to a beneficial nutrient for humans, Curr. Topics Plant Biochem. Physiol. 10, 274 (1991).
- C. J. Rainey, R. E. Christensen, L. A. Nyquist, P. L. Strong, and J. R. Coughlin, Boron daily intake from the American diet, FASEB J. 10, A785 (abstract no. 4536) (1996).
- Di Renzo, F., G. Cappelletti, M.L. Broccia, E. Giavini and E. Menegola, 2007. Boric acid inhibits embryonic histone deacetylases: A suggested mechanism to explain boric acid-related teratogenicity. Toxicol. Applied Pharmacol., 220: 178-185.
- Cox, C., 2004. Boric acid and borates. J. Pesticide Reform, 24: 10-15.
- Woods, W.G., 1994. An introduction to boron: History, sources, uses and chemistry. Environ. Health Perspect., 102: 5-11. PMID: 7889881
- United States Environmental Protection Agency, 1993. Boric Acid. United States Environmental Protection Agency. Washington, DC.
- United States Environmental Protection Agency, 1996. Report of the food quality protection act (FQPA) tolerance reassessment eligibility decision (TRED) for boric acid/sodium borate salts. United States Environmental Protection Agency.
- Habes, D., S. Morakchi, N. Aribi, J.P. Farine and N. Soltani, 2006. Boric acid toxicity to the German cockroach, Blattella germanica: Alterations in midgut structure and acetylcholinesterase and glutathione S-transferase activity. Pesticide Biochem. Physiol., 84: 17-24.
- Cochran, D.G., 1995. Toxic effects of boric acid on the German cockroach. Cell. Mol. Life Sci., 51: 561-563.
- Clausen, C.A. and V. Yang, 2007. Protecting wood from mould, decay and termites with multicomponent biocide systems. Int. Biodeteriorat. Biodegradat., 59: 20-24.
- Arslan, M., M. Topaktas and E. Rencuzogullari, 2008. The effects of boric acid on sister chromatid exchanges and chromosome aberrations in cultured human lymphocytes. Cytotechnology, 56: 91-96.
- Normah, A., K.A. Ku Hasnah and M.H. Zainab, 1984. Penyalahgunaan asid borik dalam makanan. Teknol. Makanan, 3: 54-56.
- Yiu, P.H., J. See., A. Rajan and C.F.J. Bong. 2008. Boric acid levels in fresh noodles and fish ball. Am. J. Agric. Biol. Sci., 3: 476-481.
- J. S. Schou, J. A. Jansen, and B. Aggerbeck, Human pharmacokinetics and safety of boric acid, Arch. Toxicol. 7, 232-235 (1984).
- J. A. Jansen, J. S. Schou, and B. Aggerbeck, Gastrointestinal absorption and in vitro release of boric acid from water-emulsifying ointments, Food Chem. Toxicol. 22, 49-53 (1984).
- C. Job, Absorption and excretion of orally administered boron, Z. Angew. Bader-und Klimaheilkunde 20, 137-142 (1973).
- H. I. Maibach, In vivo percutaneous absorption of boric acid, borax, and disodium octaborate tetrahydrate in humans, Biol. Trace Element Res. (current vol.).
- B. Friis-Hansen, B. Aggerbeck, and J. A. Jansen, Unaffected blood boron levels in newborn infants treated with a boric acid ointment, Food Chem. Toxicol. 20, 451-454 (1982).
- K. H. Beyer, W. F. Bergfeld, W. O. Berndt, R. K. Boutewell, W. W. Carlton, D. K. Hoffman, et al., Final report on the safety assessment of sodium borate and boric acid, ]. Am. Coil. Toxicol. 2(7), 87-125 (1983).
- G. Stuttgen, T. Siebel, and B. Aggerbeck, Absorption of boric acid through human skin depending on the type of vehicle, Arch. Dermatol. Res. 272, 21-29 (1982).
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- N. L. Ward, The determination of boron in biological materials by neutron irradiation and prompt gamma-ray spectrometry, J. Radioanalytical Nuclear Chem. 110(2), 633-639 (1987).
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- Siti-Mizura, S., E.S. Tee and H.E. Ooi, 1991. Determination of boric acid in foods: Comparative study of three methods. J. Sci. Food Agric., 55: 261-268.
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- Toxicity Litovitz, T.L., W. Klein-Schwartz, G.M. Oderda and B.F. Schmitz, 1988. Clinical manifestations of toxicity in a series of 784 boric acid ingestions.Am. J. Emerg. Med., 6: 209-213.
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- Kot, F.S., 2009. Boron sources, speciation and its potential impact on health. Rev. Environ. Sci. Biotechnol., 8: 3-28.
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Boric acid, also called boracic acid or orthoboric acid or acidum boricum, is a weak acid often used as an antiseptic, insecticide, flame retardant, in nuclear power plants to control the fission rate of uranium, and as a precursor of other chemical compounds.
Boric acid is a white, amorphous powder or colorless, crystalline solid.
Boric acid exists in the form of colorless crystals or as a white powder and is soluble in water.
The primary industrial use of boric acid is in the manufacture of monofilament fiberglass usually referred to as “textile fiberglass”. Textile fiberglass is used to reinforce plastics in applications that range from boats, to industrial piping to computer circuit boards. Boric acid is used in nuclear power plants to slowdown the rate at which fission is occurring. Fission chain reactions are generally driven by the amount of neutrons present (as products from previous fissions).
Boric acid is used in producing the glass faceplates of LCD flat panel displays. In electroplating, boric acid is used as part of some proprietary formulas. It is also used in the manufacturing of “remming mass”, a fine silica-containing powder used for producing induction furnace linings. Borates including boric acid have been used since the time of the Greeks for cleaning, preserving food, and other activities. It is used in pyrotechnics to prevent the amide-forming reaction between aluminum and nitrates. A small amount of boric acid is added to the composition to neutralize alkaline amides that can react with the aluminum. Boric acid dissolved in methane is popularly used among fire jugglers and fire spinners to create a deep green flame. Boric acid is added to salt in the curing of cattle hides, calfskins and sheepskins. Used in that way it helps to control bacteria development and also aids in the control of insects.
boric acid is an effective preservative against yeast. It is used in concentrations of 0.01 to 1.0 percent and has fair to good antiseptic properties. It may also be used as a buffer and denaturant. Boric acid is prepared from sulfuric acid and natural borax. It can cause skin rashes and irritation if used in high concentrations. The use of boric acid in cosmetic preparations is no longer very popular.
A substance made by adding hydrochloric acid to a strong, hot solution of borax and water. When cooled, this mixture forms colorless crystals of boric acid. These require washing and recrystallization. Boric acid was occasionally used as an antiseptic and in combined toning and fixing baths.
A white crystalline solid soluble
in water; in solution it is a very weak acid.
Boric acid is used as a mild antiseptic eye
lotion and was formerly used as a food
preservative. It is used in glazes for enameled
objects and is a constituent of Pyrex
Trioxoboric(III) acid is the full systematic name for the solid acid and it exists in this form in its dilute solutions. However, in more concentrated solutions polymerization occurs to give polydioxoboric(III) acid.
boric acid: Any of a number of acids containing boron and oxygen. Used without qualification the term applies to the compound H3BO3 (which is also called orthoboric acid or, technically, trioxoboric(III) acid). This is a white or colourless solid that is soluble in water and ethanol; triclinic; r.d. 1.435; m.p. 169℃. It occurs naturally in the condensate from volcanic steam vents (suffioni). Commercially, it is made by treating borate minerals (e.g. kernite, Na2B4O7.4H2O) with sulphuric acid followed by recrystallization.
In the solid there is considerable hydrogen bonding between H3BO3 molecules resulting in a layer structure, which accounts for the easy cleavage of the crystals. H3BO3 molecules also exist in dilute solutions but in more concentrated solutions polymeric acids and ions are formed (e.g. H4B2O7; pyroboric acid or tetrahydroxomonoxodiboric(III) acid). The compound is a very weak acid but also acts as a Lewis acid in accepting hydroxide ions:
B(OH)3 + H2O→B(OH)4 - + H+
If solid boric acid is heated it loses water and transforms to another acid at 300℃. This is given the formula HBO2 but is in fact a polymer (HBO2)n. It is called metaboric acid or, technically, polydioxoboric(III) acid.
Boric acid is used in the manufacture of glass (borosilicate glass), glazes and enamels, leather, paper, adhesives, and explosives. It is widely used (particularly in the USA) in detergents, and because of the ability of fused boric acid to dissolve other metal oxides it is used as a flux in brazing and welding. Because of its mild antiseptic properties it is used in the pharmaceutical industry and as a food preservative.
Boric acid is a long-standing traditional remedy with mainly antifungal and antimicrobial effects. For medicinal uses, it has become known as sal sedativum, which was discovered by Homberg, the Dutch natural philosopher, in 1702. Diluted solutions were and sometimes still are used as antiseptics for the treatment of athletes’ foot and bacterial thrush, and in much diluted solutions as eyewash. Boric acid can be prepared by reacting borax with a mineral acid: Na2B4O7 ? 10H2O + 2HCl → 4B(OH)3[or H3BO3] + 2NaCl + 5H2O In general, there are many other health claims around the clinical use of boric acid and boron-containing compounds, but many of those have no supporting clinical evidence.
Boric acid (H3BO3) is one of the boron-containing nutrients added to fertilizers. It contains around 17% boron. A solution of boric acid and water is used as a foliar spray to overcome boron deficiency.
Boric acid is a fireproofing agent for wood; a preservative, and an antiseptic. It is used in the manufacture of glass, pottery, enamels, glazes, cosmetics, cements, porcelain, borates, leather, carpets, hats, soaps; artificial gems; in tanning leather; printing, dyeing, painting, and photography.
UN 3077 Environmentally hazardous substances, solid, n.o.s., Hazard class: 9; Labels: 9—Miscellaneous hazardous material, Technical Name Required.
Boric acid decomposes in heat above 100 C, forming boric anhydride and water. Boric acid is hygroscopic; it will absorb moisture from the air. Boric acid aqueous solution is a weak acid; incompatible with strong reducing agents including alkali metals and metal hydrides (may generate explosive hydrogen gas); acetic anhydride, alkali carbonates, and hydroxides. Violent reaction with powdered potassium metal, especially if impacted. Attacks iron in the presence of moisture.
Boric acids may be recovered from organic process wastes as an alternative to disposal.
- 4-tert-Butylphenylboronic acid
- 4-Carboxyphenylboronic acid
- 3,4-Difluorophenylboronic acid
- 3,5-Difluorophenylboronic acid
- Pyridine-4-boronic acid
- Fatty accids,C3-24 and C10-18-unsat., reaction products with boric acid, diethanolamine, ethanolamine and triethanolamine
- Boric acid (H3BO3), reaction products with morpholine
- Boric acid (H3BO3), dodecyl ester, branched
- BORIC ACID B-10 ENRICHED
- Boric acid, strontium salt
- Boric acid, compd. with 2,2'-iminobis[ethanol]
- 2-Trifluoromethylphenylboronic acid
- 3,4,5-Trifluorophenylboronic acid
- Boric acid powder
- Hyaluronic acid
- Ascoric Acid
- BORIC ACID-POTASSIUM CHLORIDE-SODIUM HYDROXIDE BUFFER
- Ethyl 2-(Chlorosulfonyl)acetate