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Metals -> Elements, Metallic

Flammable agents - 3rd degree

1892 kg/cu m (solid at 17 °C); 1827 kg/cu m (liquid at 40 °C)

1.873 @25 °C

Silvery white, soft, ductile metal

Liquid (slightly above room temperature)

685 °C

671 °C @760 [mm Hg]

Melting point equals 29 °C

29 °C

28.44 °C

28.5 °C

0.0000015 [mmHg]

1.5X10-6 mm Hg at 25 °C (solid)

Cesium appears as a soft metallic solid. Melts at 85 °F. Causes burns to skin and eyes.

Shiny crystals or silver metal; [Sax] Stored immersed in mineral oil; [Merck Index]

Solid

This chemical does not meet GHS hazard criteria for 0.6% (1 of 158) of reports.

Danger

H260 (99.4%): In contact with water releases flammable gases which may ignite spontaneously [Danger Substances and mixtures which in contact with water, emit flammable gases]

P223, P231+P232, P260, P264, P264+P265, P280, P301+P330+P331, P302+P335+P334, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P321, P363, P370+P378, P402+P404, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 158 reports by companies from 7 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Chemical: Cesium

Hazard Traits - Neurotoxicity

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.)

Excerpt from ERG Guide 138 [Substances - Water-Reactive (Emitting Flammable Gases)]:

· Produce flammable gases on contact with water.

· Produce flammable gases on contact with water.

Excerpt from ERG Guide 138 [Substances - Water-Reactive (Emitting Flammable Gases)]:

· Inhalation or contact with vapors, substance or decomposition products may cause severe injury or death.

· Inhalation or contact with vapors, substance or decomposition products may cause severe injury or death.

Cesium is a naturally occurring element found combined with other elements in rocks, soil, and dust in low amounts. Naturally occurring cesium is not radioactive and is referred to as stable cesium. There is only one stable form of cesium naturally present in the environment,133Cs (read as cesium one-thirty-three). Nuclear explosions or the breakdown of uranium in fuel elements can produce two radioactive forms of cesium,134Cs and137Cs. Both isotopes decay into non-radioactive elements.134Cs and137Cs generate beta particles as they decay. It takes about 2 years for half of134Cs to give off its radiation and about 30 years for137Cs; this is called the halflife.

Spontaneously ignites in air forming cesium oxides; [Sax] Animal feeding studies: cesium is relatively nontoxic; A man who ingested 34 mg/kg of cesium chloride after morning and evening meals for 36 days experienced anorexia, nausea, and diarrhea. EKG changes have been described in patients after ingestion of cesium chloride as a homeopathic remedy. [ATSDR ToxProfiles] See Cesium hydroxide and Cesium, radioactive.

1407 138

1407 138

CESIUM reacts violently with oxidizing agents, even weaker ones. Reacts with boron trifluoride with incandescence when heated [Merck 11th ed. 1989]. Reacts explosively with maleic anhydride [Chem Safety Data Sheet SD-88 1962; Chem. Haz. Info. Series C-71 1960]. Burns in chlorine with a luminous flame [Mellor 2 Supp. 1:380 1956]. Reacts violently with most acids. Reacts violently with fluorine, chlorine, bromine and iodine. Reacts with incandescence with sulfur and phosphorus. Burns vigorously in air.

/GUIDE 138: SUBSTANCES - WATER-REACTIVE (Emitting Flammable Gases)/ Fire or Explosion: Produce flammable gases on contact with water. May ignite on contact with water or moist air. Some react vigorously or explosively on contact with water. May be ignited by heat, sparks or flames. May re-ignite after fire is extinguished. Some are transported in highly flammable liquids. Runoff may create fire or explosion hazard.

/GUIDE 138: SUBSTANCES - WATER-REACTIVE (Emitting Flammable Gases)/ Health: Inhalation or contact with vapors, substance or decomposition products may cause severe injury or death. May produce corrosive solutions on contact with water. Fire will produce irritating, corrosive and/or toxic gases. Runoff from fire control may cause pollution.

/GUIDE 138: SUBSTANCES - WATER-REACTIVE (Emitting Flammable Gases)/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. 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. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate the area before entry.

/GUIDE 138: SUBSTANCES - WATER-REACTIVE (Emitting Flammable Gases)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible.

For more DOT Emergency Guidelines (Complete) data for CESIUM, ELEMENTAL (8 total), please visit the HSDB record page.

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

Excerpt from ERG Guide 138 [Substances - Water-Reactive (Emitting Flammable Gases)]:

General First Aid:

General First Aid:

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Wear positive pressure self-contained breathing apparatus (SCBA).

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure 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 quality; potential migration in soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

Excerpt from ERG Guide 138 [Substances - Water-Reactive (Emitting Flammable Gases)]:

Immediate precautionary measure

Immediate precautionary measure

5.6 [mg/m3]

61 [mg/m3]

370 [mg/m3]

· DO NOT USE WATER OR FOAM.

· DO NOT USE WATER OR FOAM.

Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline 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 ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poison A and B/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W TKO /"To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poison A and B/

Used in photoelectric cells, photoemitter devices, scintillation counters, and an atomic clock; Also used in metallurgy to absorb gases and impurities and to dope catalysts; Cs-133 is the stable, naturally occurring isotope; Mineral sources are pollucite, lepidolite and rhodizite; Cs-137 is the radioactive isotope produced by atomic fission; [Merck Index, 2008] Cesium is released into the environment in pollucite mining and production of energy and electronics; Fly ash from coal burning power plants contains cesium; [ATSDR ToxProfiles]

Mining [Category: Industry]

Carbon dioxide purification; ferrous and nonferrous metallurgy as a scavenger of gases and other impurities; magnetohydrodynamic power generation; ion engines.

... Specialty, high-density drilling fluids used in the global oil and gas exploration industry. Cesium is also used in DNA separation techniques, infrared detectors, night vision devices, photoelectric cells, and traffic controls.

In photovoltaic cells, as a "getter" in vacuum tubes; in photoemitter devices, scintillation counters. Adsorbent in CO2 purifn; scavenger of gases and impurities in metallurgy. For doping catalysts.

Magnesium is used to obtain cesium metal from cesium hydroxide, cesium carbonate, or cesium aluminate. Vacuum redistillation at low temperature is used for final purification of the cesium metal if required.

Cesium ... import ... data are not available, and world mine production and U.S. consumption data have not been available since the late 1980s.

(1988) 23 metric tons

(1988) 0 metric tons

Cesium is not mined in the United States.

Cesium production ... data are not available, and world mine production and U.S. consumption data have not been available since the late 1980s.

Cesium halides can readily be reduced using calcium or barium, but not magnesium. Purified cesium chloride and calcium in roughly equal proportions are heated together to 700-800 °C under vacuum or in an atmosphere of an inert gas such as argon or helium, and 90-95% of the cesium is distilled as metal, although lower temperatures (300-400 °C) and higher vacuum achieve the same result but with higher purity. Magnesium is used to obtain cesium metal from cesium hydroxide, cesium carbonate, or cesium aluminate. Vacuum redistillation at low temperature is used for final purification of the cesium metal if required.

Treatment of pollucite with hydrochloric acid at elevated temperature produces a solution of chlorides of cesium, aluminum, and alkali metals, which is separated from the silica residue. The cesium is precipitated as mixed chloride with lead, antimony, or tin. Hydrolysis precipitates the auxiliary metal. Alternatives are precipitation with hydrogen sulfide or recovery of cesium by solvent extraction from the leach liquor or ion exchange from cesium chloride solution.

Alkaline decomposition can be carried out either by mixing ore with lime and calcium chloride and heating to 800 to 900 °C followed by leaching of the residue or by heating pollucite with sodium chloride and soda ash to 600 to 800 °C followed by leaching. In both cases, solutions of impure cesium chloride result. Hydrothermal alkaline leaching with Ca(OH)2 at 200 to 280 °C under high pressure has been developed as an industrial process to yield a low-purity cesium hydroxide directly from pollucite.

Cesium metal can be produced as an amalgam by electrolyzing concentrated cesium salt solutions on a mercury cathode, but reduction of solid cesium salts, especially the halides, with calcium or barium at elevated temperature and removal of cesium by vacuum distillation is the usual method