Ammonium chromate

Metals -> Chromium Compounds, Inorganic

Carcinogens

1.91 at 53.6 °F (USCG, 1999) - Denser than water; will sink

1.866

Density: 1.91 at 12 °C; decomposes at 180 °C

2.01 @25 °C

Yellow crystals

Yellow acicular crystals

Color in water: Yellow

Solubility in water: 34.4% at 50 °C

Solubility in water: 19.78% at 0 °C; 41.20% at 75 °C

In water: 27.02% at 25 °C

In water: 37 g/100 g water at 25 °C

Sparingly soluble in liquid ammonia, acetone; slightly sol in methanol; practically insoluble in ethanol

356 °F (USCG, 1999)

185 °C (decomposes)

185 °C

Ammonium chromate appears as a yellow crystalline solid. Density 1.866 g / cm3. Soluble in water. Toxic by inhalation (of dust). A strong irritant. The primary hazard is the threat to the environment. Immediate steps should be taken to limit its spread to the environment. Used in dyeing, photography, chemical analysis, and as a corrosion inhibitor.

Yellow solid; Loses some ammonia to air; [Merck Index] Fine yellow crystals; Soluble in water; [MSDSonline] Has ammonia smell; [Ullmann]

Stable under recommended storage conditions.

Loses some ammonia in air

DECOMP IN HOT WATER

Standard enthalpy of formation: -1152 kJ/mol; Standard molar entrophy: 656 J/mol-K

In air, ammonium chromate decomposes into ammonia, water, and ammonium dichromate. On heating it ignites and decomposes into chromium(III) oxide, ammonia, and nitrogen.

Monochromates, M2CrO4, hydrolyze in aqueous solution to form: HCrO4(-) + OH(-)

Readily reacts with reducing materials, including large numbers of organic compounds. These reactions may be violent. An explosion hazard when shocked or heated. Emits toxic fumes of ammonia and nitrogen oxides when heated to decomposition.

Danger

H272 (65.5%): May intensify fire; oxidizer [Danger Oxidizing liquids; Oxidizing solids]

P203, P210, P220, P233, P260, P261, P264, P271, P272, P273, P280, P284, P301+P330+P331, P302+P352, P302+P361+P354, P304+P340, P305+P354+P338, P316, P318, P321, P333+P317, P342+P316, P362+P364, P363, P370+P378, P391, P403, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 58 reports by companies from 5 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Danger

H301: Toxic if swallowed [Danger Acute toxicity, oral]

Chemical: Chromic acid (H2CrO4), diammonium salt

Restricted substance: Ammonium chromate

Ammonium chromate: HSNO Approval: HSR004341 Approved with controls

The 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.)

INHALATION: May cause irritation or ulceration of mucous membranes. EYES: Causes severe irritation and conjunctivitis. SKIN: Irritation, ulceration (chrome sores) where breaks in skin occur. INGESTION: Tends to act as its own emetic and purgative. Can cause stomach and kidney damage if retained. (USCG, 1999)

A mucous membrane irritant; A severe eye irritant; [HSDB] May cause skin sensitization; [eChemPortal: ERMA] A corrosive substance that can cause injury to the skin, eyes, and respiratory tract; May cause skin sensitization; Chromium (VI) compounds are carcinogens that can cause tissue ulceration and injury to the liver and kidneys; [MSDSonline] See Chromium and linked occupational diseases.

D007; A solid waste containing chromium may or may not become characterized as a hazardous waste when subjected to the Toxicity Characteristic Leaching Procedure listed in 40 CFR 261.24, and if so characterized, must be managed as a hazardous waste. /Chromium/

Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 1 mg/cu m. /Chromium metal and insoluble salts, as Cr/

Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 0.5 mg/cu m. /Chromium(II) compounds, as Cr/

Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 0.5 mg/cu m. /Chromium(III) compounds, as Cr/

Permissible Exposure Limit: Table Z-2 Acceptable Ceiling Concentration: 1 mg/10 cu m. /Chromic acid and chromates (as CrO3)/

AMMONIUM CHROMATE readily reacts with reducing materials, including large numbers of organic compounds. These reactions may be violent. A explosion hazard when shocked or heated [Lewis]. Emits toxic fumes of ammonia and nitrogen oxides when heated to decomposition [Sax, 9th ed., 1996, p. 207].

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.

Use water spray to cool unopened containers.

Small fire: Use water. Do not use dry chemicals or foams. CO2 or Halon may provide limited control. Large fire: Flood fire area with water from a distance. Do not move cargo or vehicle if cargo has been exposed to heat. Move containers from fire area if you can do it without risk. Fire involving tank or car/trailer loads: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn.

For more Fire Fighting Procedures (Complete) data for AMMONIUM CHROMATE (7 total), please visit the HSDB record page.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust; Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided; Methods and materials for containment and cleaning up: Sweep up and shovel. Contain spillage, and then collect with an electrically protected vacuum cleaner or by wetbrushing and place in container for disposal according to local regulations. Keep in suitable, closed containers for disposal.

In Situ Amelioration: Zeolites (Clinoptilolite) can be used on NH4. Use anion exchanger or ferric salt and sodium bicarbonate to precipitate chromate.

Availability of Countermeasure Material: Zeolites: Quarries suppliers; Anion exchangers: Water softener suppliers; Ferric chloride: Water treatment plants, photography shops; Sodium bicarbonate: and Grocery distributors, and bakeries.

Isolation and Evacuation: As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. Large Spill: Consider initial downwind evacuation for at least 100 meters (330 feet). Fire: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.

For more Cleanup Methods (Complete) data for AMMONIUM CHROMATE (8 total), please visit the HSDB record page.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number D007, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste. /Chromium/

Product: Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company. Contact a licensed professional waste disposal service to dispose of this material. Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber; Contaminated packaging: Dispose of as unused product.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

The following wastewater treatment technology has been investigated for chromium: Concentration process: Biological Treatment. /Chromium/

For more Disposal Methods (Complete) data for AMMONIUM CHROMATE (10 total), please visit the HSDB record page.

SRP: Contaminated protective clothing should be segregated in a manner such that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. The completeness of the cleaning procedures should be considered before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at the end of shift, but should remain at employee's place of work for cleaning.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust; Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.

Precautions for safe handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Further processing of solid materials may result in the formation of combustible dusts. The potential for combustible dust formation should be taken into consideration before additional processing occurs. Provide appropriate exhaust ventilation at places where dust is formed. Keep away from sources of ignition - No smoking. Keep away from heat and sources of ignition.

Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

For more Preventive Measures (Complete) data for AMMONIUM CHROMATE (15 total), please visit the HSDB record page.

0.0002 [mg/m3], as Cr(VI), inhalable particulate matter

0.0005 [mg/m3], as Cr(VI), inhalable particulate matter

8 hr Time Weighted Avg (TWA): 0.5 mg/cu m. /Chromium and Cr(III) inorganic compounds, as Cr/

A4; Not classifiable as a human carcinogen. /Chromium and Cr(III) inorganic compounds, as Cr/

Peak Exposure Recommendation: Transient increases in workers' exposure levels may exceed 3 times the value of the TLV-TWA level for no more than 15 minutes at a time, on no more than 4 occasions spaced 1 hour apart during a workday, and under no circumstances should they exceed 5 times the value of the TLV-TWA level. In addition, the 8-hour TWA is not to be exceeded for an 8-hour work period. /Chromium and Cr(III) inorganic compounds, as Cr/

8 Hr Time Weighted Avg (TWA): 0.05 mg/cu m. /Water-soluble Cr(VI) inorganic compounds, as Cr/

LC50; Species: Gambusia affinis (Western Mosquitofish); Conditions: freshwater, static, 19-23 °C, pH 7.5-7.8; Concentration: 350000 ug/L for 24 hr

LC50; Species: Gambusia affinis (Western Mosquitofish); Conditions: freshwater, static, 19-23 °C, pH 7.5-7.8; Concentration: 270000 ug/L for 48 hr

LC50; Species: Gambusia affinis (Western Mosquitofish); Conditions: freshwater, static, 19-23 °C, pH 7.5-7.8; Concentration: 240000 ug/L for 96 hr

LC50; Species: Tubifex tubifex (Tubificid Worm) mature organism, length 20 mm; Conditions: freshwater, static, 20 °C, pH 7.8; Concentration: 4360 ug/L for 24 hr (95% confidence interval: 3600-8670 ug/L)

For more Ecotoxicity Values (Complete) data for AMMONIUM CHROMATE (6 total), please visit the HSDB record page.

IDENTIFICATION AND USE: Ammonium chromate forms yellow crystals. It is used for sensitizing gelatin in photography, in textile printing pastes, in fixing chromate dyes on wool, and as a reagent in analytical chemistry. HUMAN EXPOSURE AND TOXICITY: There is no data available. ANIMAL STUDIES: Ammonium chromate was mutagenic when tested in the rec assay using Bacillus subtilis strains H17 and M45 and Salmonella typhimurium strain TA1538. The compound was tested at 0.05 M and was positive in both organisms. Ammonium chromate was tested using Escherichia coli strains WP2, WP67 and CM871 in the Escherichia coli DNA-repair test and using Salmonella typhimurium strains TA1535, TA100, TA1538, TA98, TA1537 and TA97 in the Ames reversion test. The test was performed both with and without metabolic activation. The compound was positive in the spot test and also in the 2 hr preincubation assay. In the Ames test the compound was positive in strains TA100 and TA97, weakly positive in strains TA1538, TA98, and TA1537 and negative in TA1535.

Hexavalent chromium's carcinogenic effects are caused by its metabolites, pentavalent and trivalent chromium. The DNA damage may be caused by hydroxyl radicals produced during reoxidation of pentavalent chromium by hydrogen peroxide molecules present in the cell. Trivalent chromium may also form complexes with peptides, proteins, and DNA, resulting in DNA-protein crosslinks, DNA strand breaks, DNA-DNA interstrand crosslinks, chromium-DNA adducts, chromosomal aberrations and alterations in cellular signaling pathways. It has been shown to induce carcinogenesis by overstimulating cellular regulatory pathways and increasing peroxide levels by activating certain mitogen-activated protein kinases. It can also cause transcriptional repression by cross-linking histone deacetylase 1-DNA methyltransferase 1 complexes to CYP1A1 promoter chromatin, inhibiting histone modification. Chromium may increase its own toxicity by modifying metal regulatory transcription factor 1, causing the inhibition of zinc-induced metallothionein transcription. (A12, L16, A34, A35, A36)

Breathing hexavalent chromium can cause irritation to the lining of the nose, nose ulcers, runny nose, and breathing problems, such as asthma, cough, shortness of breath, or wheezing. Ingestion of hexavalent chromium causes irritation and ulcers in the stomach and small intestine, as well as anemia. Skin contact can cause skin ulcers. (L16)

PRECAUTIONS FOR "CARCINOGENS": Whenever medical surveillance is indicated, in particular when exposure to a carcinogen has occurred, ad hoc decisions should be taken concerning ... /cytogenetic and/or other/ tests that might become useful or mandatory. /Chemical Carcinogens/

/GENOTOXICITY/ Chromic acid, diammonium salt was mutagenic when tested in the rec assay using Bacillus subtilis strains H17 and M45 and Salmonella typhimurium strain TA1538. The compound was tested at 0.05 M and was positive in both organisms.

/GENOTOXICITY/ Ammonium chromate Cr(VI) was tested using Escherichia coli strains WP2, WP67 and CM871 in the Escherichia coli DNA-repair test and using Salmonella typhimurium strains TA1535, TA100, TA1538, TA98, TA1537 and TA97 in the Ames reversion test. The test was performed both with and without S9 mix. The MIC (minimal inhibitory concentration) for ammonium chromate was 100 mug for E coli strains WP2 and WP67 without S9, 50 mug for CM871 (without S9) and with S9 mix the MIC was 150 ug for WP2, 120 ug for WP67, and 75 mug for CM871. The overall potency was a 0.003 change in MICs/nmole. The compound was positive in the spot test and also in the 2 hr preincubation assay. In the Ames test the compound was positive in strains TA100 and TA97, weakly positive in strains TA1538, TA98, and TA1537 and negative in TA1535. The potency as calculated for strain TA100 was 3.2 revertants/nmole.

WEIGHT OF EVIDENCE CHARACTERIZATION: Under the current guidelines (1986), Cr(VI) is classified as Group A - known human carcinogen by the inhalation route of exposure. Carcinogenicity by the oral route of exposure cannot be determined and is classified as Group D. Under the proposed guidelines (1996), Cr(VI) would be characterized as a known human carcinogen by the inhalation route of exposure on the following basis. Hexavalent chromium is known to be carcinogenic in humans by the inhalation route of exposure. Results of occupational epidemiological studies of chromium-exposed workers are consistent across investigators and study populations. Dose-response relationships have been established for chromium exposure and lung cancer. Chromium-exposed workers are exposed to both Cr(III) and Cr(VI) compounds. Because only Cr(VI) has been found to be carcinogenic in animal studies, however, it was concluded that only Cr(VI) should be classified as a human carcinogen. Animal data are consistent with the human carcinogenicity data on hexavalent chromium. Hexavalent chromium compounds are carcinogenic in animal bioassays, producing the following tumor types: intramuscular injection site tumors in rats and mice, intrapleural implant site tumors for various Cr(VI) compounds in rats, intrabronchial implantation site tumors for various Cr(VI) compounds in rats and subcutaneous injection site sarcomas in rats. In vitro data are suggestive of a potential mode of action for hexavalent chromium carcinogenesis. Hexavalent chromium carcinogenesis may result from the formation of mutagenic oxidatitive DNA lesions following intracellular reduction to the trivalent form. Cr(VI) readily passes through cell membranes and is rapidly reduced intracellularly to generate reactive Cr(V) and Cr(IV) intermediates and reactive oxygen species. A number of potentially mutagenic DNA lesions are formed during the reduction of Cr(VI). Hexavalent chromium is mutagenic in bacterial assays, yeasts and V79 cells, and Cr(VI) compounds decrease the fidelity of DNA synthesis in vitro and produce unscheduled DNA synthesis as a consequence of DNA damage. Chromate has been shown to transform both primary cells and cell lines. HUMAN CARCINOGENICITY DATA: Occupational exposure to chromium compounds has been studied in the chromate production, chromeplating and chrome pigment, ferrochromium production, gold mining, leather tanning and chrome alloy production industries. Workers in the chromate industry are exposed to both trivalent and hexavalent compounds of chromium. Epidemiological studies of chromate production plants in Japan, Great Britain, West Germany, and the United States have revealed a correlation between occupational exposure to chromium and lung cancer, but the specific form of chromium responsible for the induction of cancer was not identified ... Studies of chrome pigment workers have consistently demonstrated an association between occupational chromium exposure (primarily Cr(VI)) and lung cancer. Several studies of the chromeplating industry have demonstrated a positive relationship between cancer and exposure to chromium compounds. ANIMAL CARCINOGENICITY DATA: Animal data are consistent with the findings of human epidemiological studies of hexavalent chromium ... /Chromium (VI)/

Evaluation: There is sufficient evidence in humans for the carcinogenicity of chromium(VI) compounds. Chromium(VI) compounds cause cancer of the lung. Also positive associations have been observed between exposure to Chromium(IV) compounds and cancer of the nose and nasal sinuses. There is sufficient evidence in experimental animals for the carcinogenicity of chromium(VI) compounds. Chromium(VI) compounds are carcinogenic to humans (Group 1). /Chromium(VI) compounds/

Chromium Hexavalent Compounds: known to be human carcinogens. /Chromium hexavalent compound/

A1; Confirmed human carcinogen. /Water-soluble Cr(VI) inorganic compounds/

A1; Confirmed human carcinogen. /Insoluble Cr(VI) inorganic compounds/

D007; A solid waste containing chromium may or may not become characterized as a hazardous waste when subjected to the Toxicity Characteristic Leaching Procedure listed in 40 CFR 261.24, and if so characterized, must be managed as a hazardous waste. /Chromium/

... Substances for which a Federal Register notice has been published that included consideration of the serious health effects, including cancer, from ambient air exposure to the substance. Chromium is included on this list. /Chromium/

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Chromium compounds is included on this list. /Chromium compounds/

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 10 lb or 4.54 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).

Ammonium chromate 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. /Chromium and compounds/

Chromium is absorbed from oral, inhalation, or dermal exposure and distributes to nearly all tissues, with the highest concentrations found in kidney and liver. Bone is also a major storage site and may contribute to long-term retention. Hexavalent chromium's similarity to sulfate and chromate allow it to be transported into cells via sulfate transport mechanisms. Inside the cell, hexavalent chromium is reduced first to pentavalent chromium, then to trivalent chromium by many substances including ascorbate, glutathione, and nicotinamide adenine dinucleotide. Chromium is almost entirely excreted with the urine. (A12, L16)

Used in photography, textile printing, and fixing chromate dyes on wool; Also used as an analytical reagent, catalyst, and corrosion inhibitor; [HSDB]

Photographic Processing [Category: Other]

Sensitizing gelatin in photography, in textile printing pastes, in fixing chromate dyes on wool, and as a reagent in analytical chemistry.

Mordant in dyeing; photography (sensitizer for gelatin coatings); analytical reagent; catalyst; corrosion inhibitor

Chromic acid (H2CrO4), ammonium salt (1:2): ACTIVE

Incompatible with reducing agents.