Boric acid (HBO2), zinc salt (2:1)
Firebrake ZB · Zinc Borate, HeMiheptahydrate · zn100 · zb237 · zb112 · borax2335 · 2ZnO·3B2O3 · Zinc borate

Identifiers & Physical Properties
| CAS No. | 1332-07-6 |
|---|---|
| Molecular formula | B2O6Zn3 |
| Average molar mass | 313.8 g/mol |
| Monoisotopic mass | 309.77552512 g/mol |
| SMILES | [O-]B([O-])[O-].[O-]B([O-])[O-].[Zn+2].[Zn+2].[Zn+2] |
| InChIKey | BIKXLKXABVUSMH-UHFFFAOYSA-N |
| PubChem CID | 167155 |
| EC No. | 215-566-6 |
| DTXSID | DTXSID6091554 |
Chemical & Physical Properties
| Topological polar surface area | 138 |
|---|---|
| Hydrogen bond donors | 0 |
| Hydrogen bond acceptors | 6 |
| Rotatable bonds | 0 |
| Heavy atoms | 11 |
| Formal charge | 0 |
| Complexity | 8 |
| Chemical classes | Metals -> Metalloid Compounds (Boron) |
| Cosmetics | Antimicrobial |
| pH | pH = 7.6 (in deionized water) |
| Odor | None |
| Density | 2.7 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/Form | White, amorphous powderWhite granular |
| Solubility | Soluble in dilute acidsslightly soluble in water0.3% in water at 20 °C |
| Melting point | 980 °C |
| Physical Description | Zinc 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 Properties | White 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 Functions | SKIN CONDITIONING - HUMECTANT |
| LogP (partition coefficient) | -0.292 (est) |
| CAS DataBase Reference | 1332-07-6(CAS DataBase Reference) |
| EWG's Food Scores | 2-3 |
| FDA UNII | 21LB2V459E |
| Pesticides Freedom of Information Act (FOIA) | Zinc Borate |
| EPA Substance Registry System | Zinc borate (1332-07-6) |
| GHS pictogram | GHS08,GHS07,GHS09 |
| Signal word | Warning |
| GHS hazard statements | H400-H411-H319-H361 |
| GHS precautionary statements | P264-P280-P305+P351+P338-P337+P313P-P201-P202-P281-P308+P313-P405-P501-P273-P391-P501 |
| TSCA inventory status | TSCA listed |
| Hazardous substances data | 1332-07-6(Hazardous Substances Data) |
| Toxicity | Zinc 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 registrations | Active |
Safety & Regulations
| GHS classification | WarningH319: 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 information | PMN - 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 potential | Nonflammable |
| Health hazards | Inhalation 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 summary | Toxic 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 group | Non-Redox-Active Inorganic Compounds |
| Special Reports | Zinc 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 Profile | ZINC BORATE has weak oxidizing or reducing powers. Slightly soluble in water. Not water-reactive. |
| Air and Water Reactions | Slightly soluble in water. |
| CERCLA reportable quantities | Persons 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 requirements | Zinc 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 Categories | Serious eye damage/eye irritation - Category 2 |
| Standard Transportation Number | 49 633 89Zinc borate |
| First aid | INHALATION: move to fresh air. |
| Exposure control and personal protection | 0.1 [mg/m3], respirable fraction, 2 mg/m3 (inhalable fraction)-for Zn inorg. compds.[German Research Foundation (DFG)] |
| Fire fighting procedures | If material involved in fire: extingiush fire using agent suitable for type of surrounding fire. Material itself does not burn or burns with difficulty. |
| Cleanup methods | Environmental 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 methods | SRP: 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 Measures | If 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 Level | Intermediate 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 |
| Treatment | Zinc poisoning is treated symptomatically, often by administering fluids such as water or milk, or with gastric lavage. (L49) |
| Health effects | Chronic 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 values | LC50Species: 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 routes | Oral (L49)inhalation (L49)dermal (L49) |
| Toxicity summary | Anaemia 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 Symptoms | Ingestion 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 Classification | No 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 Exposure | According 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 Treatment | Immediate 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 Values | LD50 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 guidelines | EPA 5000 ug/L /Zinc/EPA 2000 ug/L /Zinc, Lifetime health advisory/ |
| TSCA inventory status | TSCA listed |
| Toxicity | Zinc 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 word | Warning |
| GHS pictogram | GHS08,GHS07,GHS09 |
| GHS hazard statements | H400-H411-H319-H361 |
| REACH registrations | Active |
| GHS precautionary statements | P264-P280-P305+P351+P338-P337+P313P-P201-P202-P281-P308+P313-P405-P501-P273-P391-P501 |
| Hazardous substances data | 1332-07-6(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.