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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HCID 167155Generated: October 23, 2026

Boric acid (HBO2), zinc salt (2:1)

Firebrake ZB · Zinc Borate, HeMiheptahydrate · zn100 · zb237 · zb112 · borax2335 · 2ZnO·3B2O3 · Zinc borate

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Boric acid (HBO2), zinc salt (2:1) molecular structure

Identifiers & Physical Properties

CAS No.1332-07-6
Molecular formulaB2O6Zn3
Average molar mass313.8 g/mol
Monoisotopic mass309.77552512 g/mol
SMILES[O-]B([O-])[O-].[O-]B([O-])[O-].[Zn+2].[Zn+2].[Zn+2]
InChIKeyBIKXLKXABVUSMH-UHFFFAOYSA-N
PubChem CID167155
EC No.215-566-6
DTXSIDDTXSID6091554

Chemical & Physical Properties

Topological polar surface area138
Hydrogen bond donors0
Hydrogen bond acceptors6
Rotatable bonds0
Heavy atoms11
Formal charge0
Complexity8
Chemical classesMetals -> Metalloid Compounds (Boron)
CosmeticsAntimicrobial
pHpH = 7.6 (in deionized water)
OdorNone
Density2.7 at 68 °F (USCG, 1999) - Denser than waterwill sink3.64 g/cu cmDensity: 40 to 40 lbs/cu ft (bulk)3.64 g/cm3
Color/FormWhite, amorphous powderWhite granular
SolubilitySoluble in dilute acidsslightly soluble in water0.3% in water at 20 °C
Melting point980 °C
Physical DescriptionZinc borate appears as a white powder of variable composition. (typically 45% ZnO, 34% B2O3 and 20% H2O). Slightly soluble in water. The primary hazard is the threat to the environment. Immediate steps should be taken to limit its spread to the environment. It is used as a fungus and mildew inhibitor, to fire proof textiles, and for other uses.White odorless solidPowder (ceramic grade) = 99.95% pureCommercial grade = about 50% zinc oxide and 30% boric anhydride[HSDB] White powder[MSDSonline]
Other Experimental PropertiesWhite amorphous powderMF: 3ZnO.2B2O3MW: 383.466Density/Specific gravity: 3.64 g/cu cmSlightly sol in cold waterSoluble in dilute acid. 27043-84-1 /Zinc borate27043-84-1/White crystalsMF: 2ZnO.3B2O3.3.5H20MW: 434.69MP: 980 °Cdensity = 4.22 g/cu cminsoluble in water. 12513-27-8 /Zinc borate hemiheptahydrate/White powderMF: 2ZnO.3B2O3.5H20MW: 461.753Density: 3.64 g/cu cmsolubility in water = 0.007 g/100 g water at 25 °Cslightly soluble in hydrochloric acid. 12536-65-2 /Zinc pentahydrate/White hygroscopic solidMF: ZnO(B2O3)2.6H2OMW: 429.305MP: 100 °CDensity: 2.57 g/cu cmvery soluble in water. 13517-27-6 /Zinc hexahydrate/
Cosmetics Ingredients FunctionsSKIN CONDITIONING - HUMECTANT
LogP (partition coefficient)-0.292 (est)
CAS DataBase Reference1332-07-6(CAS DataBase Reference)
EWG's Food Scores2-3
FDA UNII21LB2V459E
Pesticides Freedom of Information Act (FOIA)Zinc Borate
EPA Substance Registry SystemZinc borate (1332-07-6)
GHS pictogramGHS08,GHS07,GHS09
Signal wordWarning
GHS hazard statementsH400-H411-H319-H361
GHS precautionary statementsP264-P280-P305+P351+P338-P337+P313P-P201-P202-P281-P308+P313-P405-P501-P273-P391-P501
TSCA inventory statusTSCA listed
Hazardous substances data1332-07-6(Hazardous Substances Data)
ToxicityZinc borate 2ZnO3B2O3·3.5H2O has an acute oral toxicity in rats LD50 >10000 mg/kg body weight and acute dermal toxicity in rabbits LD50>10000 mg/kg body weight. It is not a skin irritant and gives a negative response in the Ames mutagenicity test (Kirk-Othmer, 1994).
REACH registrationsActive

Safety & Regulations

GHS classificationWarningH319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]P264+P265, P280, P305+P351+P338, and P337+P317 (click each P-code to see the statement)
Regulatory informationPMN - indicates a commenced PMN (Pre-Manufacture Notices) substance.Zinc borate: Does not have an individual approval but may be used under an appropriate group standardThe New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)
Fire potentialNonflammable
Health hazardsInhalation of dust may irritate nose and throat. Ingestion can cause gastrointestinal disturbances, convulsions, central nervous depressions, skin eruptions, shock, and death. Contact with eyes or skin causes irritation. (USCG, 1999)
Hazards summaryToxic by ingestionA skin and eye irritant[HSDB]Zinc salts are irritating to the GI tractNo cumulative effects except digestive disorders[EPA OHM/TADS] Has not been tested for reproductive or other chronic effects[NJ-HSFS] An irritant[MSDSonline] See Boric acid.
Reactive groupNon-Redox-Active Inorganic Compounds
Special ReportsZinc and Health. Current Bibliographies in Medicine 98-3. Public Services Division/National Library of Medicine. 3619 citations January, 1990-June, 1998.[Available from, as of November 2, 1998: http://www.nlm.nih.gov/archive/20040831/pubs/cbm/zinc.html]USEPAAmbient Water Quality Criteria Doc: Zinc (1980) EPA 400/5-80-079Ambient Water Quality Criteria Doc: Zinc (1987) EPA 400/5-87-003Arvidson, B. A Review of Axonal Transport of Metals. Toxicology 88: 1-14 (19994) Recent findings regarding axonal transport of metals, including zinc.For more Special Reports (Complete) data for ZINC BORATE (6 total), please visit the HSDB record page.
Reactivity ProfileZINC BORATE has weak oxidizing or reducing powers. Slightly soluble in water. Not water-reactive.
Air and Water ReactionsSlightly soluble in water.
CERCLA reportable quantitiesPersons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 1000 lb or 454 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).
Clean Water Act requirementsZinc borate is designated as a hazardous substance under section 311(b)(2)(A) of the Federal Water Pollution Control Act and further regulated by the Clean Water Act Amendments of 1977 and 1978. These regulations apply to discharges of this substance. This designation includes any isomers and hydrates, as well as any solutions and mixtures containing this substance.Toxic pollutant designated pursuant to section 307(a)(1) of the Federal Water Pollution Control Act and is subject to effluent limitations. /Zinc and compounds/For total recoverable zinc the criterion to protect freshwater aquatic life ... is 47 ng/L as a 24 hr average ... at hardnesses of 50, 100, and 200 mg/L as CaCO3 the concentration of total recoverable zinc should not exceed 180, 320, 570 ug/L at any time. /Soluble zinc salts/For total recoverable zinc the criterion to protect saltwater aquatic life ... is 58 ug/L as a 24 hr average and the concentration should not exceed 170 ug/L at any time. /Soluble zinc salts/
Hazard Classes and CategoriesSerious eye damage/eye irritation - Category 2
Standard Transportation Number49 633 89Zinc borate
First aidINHALATION: move to fresh air.
Exposure control and personal protection0.1 [mg/m3], respirable fraction, 2 mg/m3 (inhalable fraction)-for Zn inorg. compds.[German Research Foundation (DFG)]
Fire fighting proceduresIf material involved in fire: extingiush fire using agent suitable for type of surrounding fire. Material itself does not burn or burns with difficulty.
Cleanup methodsEnvironmental considerations: Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be contained with a flexible impermeable membrane liner./ Cover solids with a plastic sheet to prevent dissolving in rain or fire fighting water.Environmental considerations: Water spill: Neutralize with agricultural lime (CaO), crushed limestone (CaCO3), or sodium bicarbonate (NaHCO3). Add soda ash (Na2CO3). Adjust pH to neutral (pH 7). Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates.
Disposal methodsSRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air qualitypotential migration in soil or watereffects on animal and plant lifeand conformance with environmental and public health regulations.
Preventive MeasuresIf material not involved in fire: Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Keep upwind. Wear appropriate chemical protective gloves, boots and goggles. Avoid breathing vapors or dust. Wash away any material which may have contacted the body with copious amounts of water or soap and water.SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.
Minimum Risk LevelIntermediate Oral: 0.3 mg/kg/day (L134) Chronic Oral: 0.3 mg/kg/day (L134)
Personal Protective Equipment (PPE)Dust maskgoggles or face shieldprotective gloves (USCG, 1999)/NIOSH certified respirator/protective gloves
TreatmentZinc poisoning is treated symptomatically, often by administering fluids such as water or milk, or with gastric lavage. (L49)
Health effectsChronic exposure to zinc causes anemia, atazia, lethargy, and decreases the level of good cholesterol in the body. It is also believed to cause pancreatic and reproductive damage. (L49)
Ecotoxicity valuesLC50Species: Anas platyrhynchos (Mallard duck) age 10 daysdiet >5620 ppm for 8 daysLD50Species: Colinus virginianus (Northern Bobwhite Quail) age 5 monthsoral via capsule >2250 mg/kgEC50Species: Daphnia magna (Water Flea) age <24 hrConditions: freshwater, staticConcentration: 75000 ug/L for 48 hr (95% confidence interval: 50000-120000 ug/L)Effect: intoxication, immobilization /100% purity formulation/Species: Lepomis macrochirus (Bluegill)Concentration: >335000 ug/L for 96 hr /100% purity formulation/Species: Oncorhynchus mykiss (Rainbow Trout)Concentration: 2700 ug/L for 96 hr (95% confidence interval: 1800-3400 ug/L) /100% purity formulation/
Exposure routesOral (L49)inhalation (L49)dermal (L49)
Toxicity summaryAnaemia results from the excessive absorption of zinc suppressing copper and iron absorption, most likely through competitive binding of intestinal mucosal cells. Unbalanced levels of copper and zinc binding to Cu,Zn-superoxide dismutase has been linked to amyotrophic lateral sclerosis (ALS). Stomach acid dissolves metallic zinc to give corrosive zinc chloride, which can cause damage to the stomach lining. Metal fume fever is thought to be an immune response to inhaled zinc. (L48, L49, A49)
Ecotoxicity excerpts/BIRDS and MAMMALS/ Avian acute oral study indicated that the bobwhite quail (Colinus virginianus), based on signs of toxicity, mortality, reduction of body weight gain and feed consumption was characterized as practically non-toxic to bobwhite quail. The LD50 was determined to be >2250 mg/kg, the highest dosage tested./BIRDS and MAMMALS/ In avian dietary studies, the LC50 value of zinc borate in the mallard ducklings (Anas platyrhynchos) is estimated to be greater than 5,620 ppm. No mortality occurred in either the control or treated groups. A slight reduction in body weight was observed at the 6,520 ppm concentration during the exposure period. There was no effect on feed consumption at any concentration tested./AQUATIC SPECIES/ The acute toxicity of zinc borate to bluegill sunfish (Lepomis macrochirus) was tested under static conditions at mean concentrations of 94, 137, 182, 248, and 335 ppm. The 96 hr LC50 for bluegill sunfish was shown to be greater than 335 ppm. These results indicate that zinc borate is practically nontoxic to the fish species tested.
Signs and SymptomsIngestion of large doses of zinc causes stomach cramps, nausea, and vomiting. Acute inhalation of large amounts of zinc causes metal fume fever, which is characterized by chills, fever, headache, weakness, dryness of the nose and throat, chest pain, and coughing. Dermal contact with zinc results in skin irritation. (L49)
Carcinogen ClassificationNo indication of carcinogenicity to humans (not listed by IARC).
Non-Human Toxicity Excerpts/GENOTOXICITY/ In the Salmonella/microsomal Assay (Ames Bioassay) for bacterial mutagenic activity, zinc borate did not elicit any mutagenic response in Salmonella tester strains when tested either with or without a metabolic activation system./OTHER TOXICITY INFORMATION/ In a dermal sensitization study involving guinea pigs, zinc borate showed no evidence of /sensitization/./OTHER TOXICITY INFORMATION/ Primary Dermal Irritation/Corrosivity in Albino Rabbits - The Primary Irritation Index of zinc borate in rabbits was found to be 0. Therefore, it is not considered to be an irritant or corrosive./OTHER TOXICITY INFORMATION/ Zinc borate was shown to be an eye irritant producing mild conjunctivitis in albino rabbits.
Probable Routes of Human ExposureAccording to the 2006 TSCA Inventory Update Reporting data, the number of persons reasonably likely to be exposed in the industrial manufacturing, processing, and use of zinc borate is 100 to 999the data may be greatly underestimated(1).NIOSH (NOES Survey 1981-1983) has statistically estimated that 20,343 workers (4,266 of these were female) were potentially exposed to zinc borate in the US(1). Occupational exposure to zinc borate may occur through inhalation and dermal contact with this compound at workplaces where zinc borate is produced or used(SRC).
Antidote and Emergency TreatmentImmediate first aid: Remove patient from contact with the material. Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Zinc and related compounds/Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . Monitor for shock and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . /Zinc and related compounds/Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine, hydrochloride to assist eye irrigation ... . /Zinc and related compounds/Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Boron and Related Compounds/For more Antidote and Emergency Treatment (Complete) data for ZINC BORATE (6 total), please visit the HSDB record page.
Non-Human Toxicity ValuesLD50 Rabbits (male and female albino rabbits) dermal greater than 10 g/kgLD50 Rat(male) oral greater than 10 g/kg
State drinking water guidelines(AZ) ARIZONA 5000 ug/L /Zinc/(MN) MINNESOTA 2000 ug/L /Zinc/
Federal drinking water guidelinesEPA 5000 ug/L /Zinc/EPA 2000 ug/L /Zinc, Lifetime health advisory/
TSCA inventory statusTSCA listed
ToxicityZinc borate 2ZnO3B2O3·3.5H2O has an acute oral toxicity in rats LD50 >10000 mg/kg body weight and acute dermal toxicity in rabbits LD50>10000 mg/kg body weight. It is not a skin irritant and gives a negative response in the Ames mutagenicity test (Kirk-Othmer, 1994).
Signal wordWarning
GHS pictogramGHS08,GHS07,GHS09
GHS hazard statementsH400-H411-H319-H361
REACH registrationsActive
GHS precautionary statementsP264-P280-P305+P351+P338-P337+P313P-P201-P202-P281-P308+P313-P405-P501-P273-P391-P501
Hazardous substances data1332-07-6(Hazardous Substances Data)

Applications & Uses

Uses

Zinc borate is prepared as an insoluble double salt from water-soluble zinc and boron compounds. Compounds having varying amounts of zinc, boron, and water of hydration are available. The ratio of these components affects the temperature at which the flame-inhibiting powers are activated, as well as the temperature at which they can be processed. Zinc borates can either be used alone or in combination with other halogen synergists, such as antimony oxide. In some instances zinc borate is also used with alumina trihydrate to form a glass-like substance that inhibits polymer degradation.

Uses

Medicine, fireproofing textiles, fungistat and mildew inhibitor, flux in ceramics.