Cadmium Oxide

Metals -> Cadmium Compounds, Inorganic

Carcinogens

8.15 crystalline form; 6.95 amorphous form (EPA, 1998)

8.15 g/cu cm

Decomposes at 950 °C; Density: 8.15 /Crystals/

Density (amorphous): 6.9 g/cm³

8.65 (metal)

8.15 @25 °C

Brown cubic crystals

Dark-brown, infusible powder or cubic crystals

... Yellow-brown, finely divided particulate dispersed in air. /fume/

Colorless, amorphous powder (form 1)

less than 1 mg/mL at 68 °F (NTP, 1992)

Soluble in dilute acid

Slowly soluble in ammonium salts

Insoluble in alkalies

Insoluble in water

Solubility in water: none

2838 °F at 760 mmHg (sublimes) (NTP, 1992)

1559 °C (sublimes)

2838 °F (sublimes)

Decomposes

When heated to decomposition it emits toxic fumes of /cadmium/.

900-1000 °C (amorphous)

Greater than 2732 °F (EPA, 1998)

2599 °F

2599 °F

1 mmHg at 1832 °F (EPA, 1998)

Vapor pressure: 10 mm Hg at 1149 °C; 40 mm Hg at 1257 °C; 100 mm Hg at 1341 °C; 400 mm Hg at 1484 °C.

1 Pa at 770 °C (sublimes); 10 Pa at 866 °C (sublimes); 100 Pa at 983 °C (sublimes); 1 kPa at 1128 °C (sublimes); 10 kPa at 1314 °C (sublimes); 100 kPa at 1558 °C (sublimes)

0 mmHg (approx)

0 mmHg (approx)

Cadmium oxide appears as brown crystals or brown amorphous powder. Used as an electroplating chemical and in the manufacture of cadmium electrodes. Is a component of silver alloys, phosphors, semiconductors, glass and ceramic glazes. Formerly used by veterinarians to kill worms and parasites. (EPA, 1998)

Dry Powder; Wet Solid; Other Solid

"Cadmium oxide (CdO) may be in the form of a white amorphous powder or as red or brown crystals: it is formed when cadmium is burned or heated." [ACGIH]

ODOURLESS BROWN CRYSTALS OR AMORPHOUS POWDER.

odorless, yellow-brown, finely divided particulate dispersed in air.

Odorless, yellow-brown, finely divided particulate dispersed in air. [Note: See listing for Cadmium dust for properties of Cd.]

Danger

H330: Fatal if inhaled [Danger Acute toxicity, inhalation]

P203, P260, P264, P270, P271, P273, P280, P284, P304+P340, P316, P318, P319, P320, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Danger

H301 (37%): Toxic if swallowed [Danger Acute toxicity, oral]

P203, P260, P264, P270, P271, P273, P280, P284, P301+P316, P304+P340, P316, P318, P319, P320, P321, P330, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Chemical: Cadmium oxide (CdO)

Hazard Traits - Carcinogenicity

Cadmium oxide (CdO) is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Cadmium oxide (CdO) are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Status: Active Update: 23-12-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/15016

Restricted substance: Cadmium oxide

Substance: Cadmium oxide

When heated to decomposition, it emits toxic fumes of cadmium. (Non-Specific -- Cadmium Compounds) Fire may produce irritating or poisonous gases. Runoff from fire control or dilution water may cause pollution. Oxides of cadmium react explosively with magnesium when heated. (EPA, 1998)

Not combustible. Gives off irritating or toxic fumes (or gases) in a fire.

The lethal inhalation dose of cadmium oxide in humans is 2,500 mg/m3 for a 1 minute exposure. Lethal exposure has been established at 50 mg (cadmium)/m3 for 1 hour for cadmium oxide dust and 1/2 hour for the fume. These concentrations may be inhaled without sufficient discomfort to warn worker of exposure. Inhalation may cause acute tracheobronchitis, pneumonitis, and pulmonary edema. Exposure can cause kidney and lung damage. Acute exposure by inhalation may cause death by anoxia. The lowest human toxic inhalation concentration is 8.630 mg/m3/5 hours for the fume. Persons with respiratory disorders should be excluded from contact with this material. (EPA, 1998)

May cause respiratory tract irritation and pulmonary edema; May cause kidney injury; [ICSC]

The major hazards encountered in the use and handling of cadmium oxide stem from its toxicologic properties. Toxic primarily by ingestion and inhalation, exposure to this odorless, brown crystalline substance may occur from the smelting and refining of ore, and from the smelting and refining of zinc, lead, and copper ores, spraying cadmium-containing pigments, and from its use in electroplating, as a chemical intermediate or catalyst and in ceramic glazes, silver-zinc storage batteries, and plastics. Effects from exposure may include headache, shortness of breath, chest pain, fever, kidney damage, emphysema, chronic bronchitis, and pulmonary edema (possibly resulting in death). NIOSH has recommended that cadmium (dust and fumes) be treated as a potential human carcinogen. The OSHA PEL for cadmium fume is 0.1 mg Cd/cu m, and for cadmium dust is 0.2 mg Cd/cu m. Processes and operations which may release cadmium fumes or dust should be enclosed and fitted with exhaust ventilation to maintain exposure at or below recommended levels. In activities where over-exposure is possible workers should wear a high efficiency particulate filter respirator or self-contained breathing apparatus. Protective clothing also should be worn. Preferably this should include disposable one-piece suits (close-fitting at the ankles and wrists, gloves, hair covering, and overshoes.These should be removed before leaving work. If contact should occur, immediately wash contaminated skin with large amounts of water. Do not eat, smoke, or drink in work areas. Cadmium oxide presents only a moderate fire hazard(when in the form of dust) if exposed to heat, flame, or by chemical reaction with oxidizing agents, metals, hydrogen azide, zinc, selenium, or tellurium. Wear a self-contained breathing apparatus when fighting such fires. Cadmium oxide should be stored in cool, well-ventilated areas, out of direct rays of the sun, and away from fire hazards. If hazardous concentrations of cadmium oxide are accidentally released, remove all ignition sources, ventilate the area, and collect the released material in closed containers for disposal. Before implementing land disposal of waste cadmium oxide, consult environmental regulatory agencies for guidance.

DHHS/NTP; NTP Toxicity Studies of Cadmium Oxide Administered by Inhalation to F344/N Rats and B6C3F1 Mice. Toxicity Rpt Series No. 39 NIH Publication No. 95-3388 (1995)

National Toxicology Program. Eleventh Report on Carcinogens (2005). The Report on Carcinogens is an informational scientific and public health document that identifies and discusses substances (including agents, mixtures, or exposure circumstances) that may pose a carcinogenic hazard to human health. Cadmium and Cadmium Compounds are listed as known to be human carcinogens. /Cadmium and Cadmium Compounds/[Available from, as of July 31, 2009: http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s028cadm.pdf]

D006; A solid waste containing cadmium 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. /Cadmium/

(Non-Specific -- Cadmium Compounds) Wear self-contained breathing apparatus and full protective clothing. Move container from fire if you can do so without risk.

In case of fire in the surroundings, use appropriate extinguishing media.

Fresh air, rest. Half-upright position. Refer for medical attention.

Rinse skin with plenty of water or shower.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Refer for medical attention .

Warning: Effects may be delayed for hours. Caution is advised.

(General first aid procedures)

Biological Exposure Indices (BEI) [ACGIH] - Cd in urine = 5 ug/g creatinine; Cd in blood = 5 ug/L; sampling time not critical; Monitoring in blood should be preferred during the initial year of exposure and whenever changes in the degree of exposure are suspected. [ACGIH]

If material on fire or involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Use water in flooding quantities as fog. Use "alcohol" foam, dry chemical or carbon dioxide. /Cadmium compounds, NOS/

If dust is released in a hazardous concentration: (1) remove all ignition sources; (2) ventilate area of release; and (3) collect released material and place in sealed containers in secured sanitary landfill. (Non-Specific -- Cadmium Compounds) Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind, keep out of low areas. If pollution of water occurs, notify proper authorities. Do not touch spilled material; stop leak if you can do so without risk. Absorb small spills with sand or other noncombustible absorbent material and place into containers for later disposal.

CADMIUM DUST MAY BE DISPOSED OF IN SEALED CONTAINERS IN SECURED SANITARY /SRP: HAZARDOUS WASTE/ LANDFILL.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number D006, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste. /Cadmium/

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Vacuum spilled material with specialist equipment. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

Provide adequate ventilation

/If cadmium oxide is involved in a spill on water/: Notify local health and wildlife officials and operators of nearby water intakes.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers.

SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants.

For more Preventive Measures (Complete) data for CADMIUM OXIDE (6 total), please visit the HSDB record page.

The substance can be absorbed into the body by inhalation of its aerosol and by ingestion.

inhalation

Oral (L6) ; inhalation (L6) ; dermal (L6)

Cadmium initially binds to metallothionein and is transported to the kidney. Toxic effects are observed once the concentration of cadmium exceeds that of available metallothionein, and it has also been shown that the cadmium-metallothionein complex may be damaging. Accumulation of cadmium in the kidney results in increased excretion of vital low and high weight molecular proteins. Cadmium is a high affinity zinc analog and can interfere in its biological processes. It also binds to and activates the estrogen receptor, likely stimulating the growth of certain types of cancer cells and causing other estrogenic effects, such as reproductive dysfunction. Cadmium causes cell apoptosis by activating mitogen-activated protein kinases. (L8, A18, A19, A28)

Cough. Laboured breathing. Shortness of breath. Symptoms may be delayed.

Redness. Pain.

Abdominal cramps. Diarrhoea. Nausea. Vomiting.

pulmonary edema, dyspnea (breathing difficulty), cough, chest tightness, substernal (occurring beneath the sternum) pain; headache; chills, muscle aches; nausea, vomiting, diarrhea; emphysema, proteinuria, anosmia (loss of the sense of smell), mild anemia; [potential occupational carcinogen]

Acute inhalation of cadmium fumes results in metal fume fever, which is characterized by chills, fever, headache, weakness, dryness of the nose and throat, chest pain, and coughing. Ingestion of cadmium causes vomiting and diarrhea. (L6)

The following link will take the user to the National Toxicology Program (NTP) Test Agent Search Results page, which tabulates all of the "Standard Toxicology & Carcinogenesis Studies", "Developmental Studies", and "Genetic Toxicity Studies" performed with this chemical. Clicking on the "Testing Status" link will take the user to the status (i.e., in review, in progress, in preparation, on test, completed, etc.) and results of all the studies that the NTP has done on this chemical.[Available from: http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=1306-19-0]

Cadmium oxide was evaluated for clastogenicity in groups of 20 male Long-Evans rats injected intraperitoneally with total dose levels of 0 or 5 mg/kg bw, in three equal increments at 2 day intervals. Blood and bone marrow samples were obtained from each rat at 1 and 30 days after treatment, for determination of chromosomal abnormalities. The treatment increased the frequency of 1 type of chromosomal aberration (gap/break) in bone marrow cells obtained on day 1, indicating that the test compound was positive for clastogenicity in rats under the conditions of this assay. Positive control treatment with a single intraperitoneal injection of 0.3 mg/kg triethylenemelamine produced a significant increase in the frequency of chromosomal aberrations in bone marrow cells collected on day 1; bone marrow cells collected from positive control rats on day 30 and blood cells collected on day 1 or 30 were similar to negative controls in frequency of chromosomal aberrations.

Cadmium content /in/: sphalerite: 0.0001-2%; greenockite: 77.8%; hawleyite: 77.8%; chalcopyrite: < 0.4-110 ppm; marcasite: < 0.3-<50 ppm; arsenopyrite: < 5 ppm; galena: < 10-3000 ppm; pyrite: < 0.06-42 ppm; pyrrhotite: trace; tetrahedrite: 80-2000 ppm; magnetite: 0-0.31 ppm; cadmium oxide: 87.5%; limonite: < 5-1000 ppm; wad and manganese oxides: < 10-1000 ppm; anglesite: 120->1000 ppm; barite: < 0.2 ppm; anhydrite and gypsum: < 0.2 ppm; calcite: < 1-23 ppm; smithsonite: 0.1-2.35%; otavite: 65.18%; pyromorphite: < 1-8 ppm; scorodite: < 1-5.8 ppm; beudantite: 100-1000 ppm; apatite: 0.14-0.15 ppm; bindheimite: 100-1000 ppm; silicates: 0.03-2.8 ppm.

D006; A solid waste containing cadmium 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. /Cadmium/

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. Cadmium oxide is included on this list.

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Cadmium oxide is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 100 or 10,000 lbs. Extremely hazardous substances that are solids are subject to either of two threshold planning quantities ... The lower quantity applies only if the solid exists in powdered form and has a particle size less than 100 microns; or is handled in solution or in molten form; or meets the criteria for a National Fire Protection Association (NFPA) rating of 2, 3 or 4 for reactivity. If the solid does not meet any of these criteria, it is subject to the upper ... threshold planning quantity ... .

(AZ) ARIZONA 5 ug/L /Cadmium/

(ME) MAINE 3.5 ug/L /Cadmium/

(MN) MINNESOTA 4 ug/L /Cadmium/

Rats were intratracheally... /dosed with/ 36.5 or 27.5 ug of cadmium (Cd) as soluble cadmium chloride (CdCl2) and insoluble cadmium oxide (CdO) salts. The retention of metal in lungs, liver and kidney was assessed by atomic adsorption spectrophotometer. The animals were ip primed with sheep red blood cells (SRBC) and assessed for the number of antibody forming cells in lung associated lymph nodes (LALN) and spleen. Both the compounds had similar retention of metal in lungs but CdO induced more pulmonary inflammatory and degradative changes than CdCl2. The larger influx of polymorphonuclear cells (PMNs) following CdO exposure appears to be due to the absence of protection afforded by Cd induced metallothionein cytoplasmic protein while the Cd metallothionein complex formed in the case of CdCl2 is more protective. However both forms of Cd had similar local immunosuppressive potential but CdO had more prolonged suppressive effect

Surfactant lipids of the alveolar space protect the lung from various environmental stimuli. We investigated the influence of ultrafine (UF) CdO particles inhalation on two key enzymes involved in lung sphingolipid metabolism, serine palmitoyltransferase (SPT), and sphingomyelinase (SMase). Rats inhaled either 0.63 mg UF-CdO/cu m for 6 hr (group 1), or 1.08 mg UF-CdO/cu m 12 hr/day for 10 days (group 2). Two corresponding control groups inhaled filtered clean air. Additional rats intratracheally instilled with lipopolysaccharide (LPS) were used as positive controls. Semiquantitative reverse-transcription polymerase chain reaction (RT-PCR) of lung tissue showed a significant increase in the level of SPT mRNA (LCB2 subunit) expression in group 2 compared to the corresponding controls (p <0.01). Group 1 and LPS were not statistically different from control. No alteration in the mRNA level of SMase was detected in any exposure group. The immunohistochemical analysis showed that SPT (LCB2 subunit) localization was stronger in the alveolar type II cells of group 2 lungs compared to the corresponding controls. These results were correlated with alterations in ...cellular and biochemical parameters and lung morphology. Since SPT is the key enzyme for de novo sphingolipid synthesis in lung surfactant and SMase is responsible for sphingomyelin catabolism, we can postulate that high-dose UF-CdO exposure for 10 days induces an increase in sphingolipid synthesis in the type II cells of rat lungs that would not be promptly followed by its degradation.

Cadmium is absorbed from oral, inhalation, and dermal routes. Cadmium initially binds to metallothionein and albumin and is transported mainly to the kidney and liver. Toxic effects are observed once the concentration of cadmium exceeds that of available metallothionein, and it has also been shown that the cadmium-metallothionein complex may be damaging. Cadmium is not known to undergo any direct metabolic conversion and is excreted unchanged, mainly in the urine. (L6)

Cadmium is a metallic impurity in various minerals. The two main cadmium exposure sources in general population are food and tobacco smoking...Cadmium is a cumulative toxic substance whose half-time for elimination is about 20 to 40 years and it is mainly stored in the liver and kidneys. Inhalation of cadmium oxide fumes may cause inhalation fevers or chemical pneumonitis. Cadmium chronic poisoning causes mainly renal tubulopathy and could be the cause of osteomalacia and diffuse osteoporosis. Cadmium is classified as certain carcinogen agent for humans by International Agency for Research on Cancer (IARC). The most relevant biological index exposure is the urinary cadmium. According to literature, no chelating agent can be still used in human cadmium poisonings. In France, some diseases caused by occupational exposure to cadmium may be compensated.

1 YR INHALATION OF CADMIUM OXIDE ... BY DOGS @ LEVELS OF 3-7 MG/CU M DAILY RESULTED IN ... BLOOD CADMIUM CONCN AVG 0.22 MG% & URINE ... WERE 0.36 MG/L. MOST ... CADMIUM ... RETAINED IN LUNGS, CONSIDERABLE AMT IN KIDNEY & LIVER ... LESSER AMT IN BONE & TEETH. LACK OF EFFECT ... ATTRIBUTED TO LOW RATE OF SOLUBILITY ...

... ARC-PRODUCED CD FUME PARTICLE DEPOSITION IN LARGE NUMBER OF 5 ANIMAL SPECIES AT LD50 DOSES ... /WITH/ PARTICULATE DIAMETER ... FROM 0.3 TO 0.5 MU ... /SHOWED/ AVG FUME DEPOSITION IN LUNG ... ABOUT SAME FOR ALL SPECIES, 11%, WITH RANGE BETWEEN 4.3 & 21.7% ...

RATS WHICH DIED WITHIN 3 DAYS OF EXPOSURE TO AEROSOL OF CADMIUM OXIDE (60 M UG/L FOR 30 MIN) SHOWED LUNG LEVEL OF 26.9 UG.

For more Absorption, Distribution and Excretion (Complete) data for CADMIUM OXIDE (7 total), please visit the HSDB record page.

Used in silver-zinc storage batteries, Teflon, phosphors, semiconductors, silver alloys, glass, nematocides, ascaricides, catalysts, electroplating, ceramic glazes, and PVC heat stabilizers; [HSDB] Combined with an alkali-metal cyanide in baths for cadmium electroplating; [Ullmann]

Metal Preparation and Pouring [Category: Foundry]

Ceramics making [Category: Hobbies]

High purity cadmium oxide is used as a second polarizer (in addition to silver oxide) in silver-zinc storage batteries.

Oxidation of the sulfide or sulfite under carefully controlled oxidizing atmospheres at high temperature. An alternate method involves treatment of powdered cadmium nitrate, halide, oxide, or carbonate with dimethyl sulfate.

The hydrated bromide is prepared by dissolution of cadmium carbonate, oxide, sulfide, or hydroxide in hydrobromic acid. /Hydrated cadmium bromide/

Cadmium oxide, powder reagent grade has the following impurities: chloride: 0.002%; nitrate (NO3); 0.01%; sulfate (SO4); 0.20%; copper: 0.005%; iron: 0.002%; lead: 0.01%.

Cadmium oxide ... impurities (%): Cl, 0.002; NO3, 0.01; SO4, 0.20; Cu, 0.005; Fe, 0.002; and Pb, 0.01.

2023: 2,081,610 lb

Production volumes for non-confidential chemicals reported under the Inventory Update Rule. [Table#3347]

Production volume for non-confidential chemicals reported under the 2006 Inventory Update Rule. Chemical: Cadmium oxide. Aggregated National Production Volume: < 500,000 pounds.

Cadmium oxide is produced by evaporation of cadmium metal and oxidation of the vapor. It can also be obtained by thermal decomposition of cadmium nitrate or carbonate or by oxidation of molten cadmium by an oxidizing agent. Commercial cadmium oxide should be completely soluble in sodium cyanide solution and contain no heavy-metal or sulfur impurities.

Pure Cd metal is melted and then vaporized whereupon air is blown through the hot vapor, oxidizing the cadmium and carrying the product to a baghouse. The resultant oxide (particle size controlled by the /air to cadmium/ ratio) is calcined at 550 °C to ensure uniform properties.

Reagent grade: 99.0% assay

Cadmium oxide - purities: 99.0-99.9999%; reagent grade, 99.0%; commercial grade, 99.7%.

Computer and Electronic Product Manufacturing

Cadmium oxide (CdO): ACTIVE

Some fume and dust from welding processes ... may contain cadmium or cadmium oxide compounds. The specific form and concentration of cadmium present ... are dependent on the composition of the filler metal, base metals, metal coatings, atmosphere, flux, and welding process.