Samarium

7.52 g cu cm at 25 °C

7.536 @25 °C

1794 °C

1778 °C @760 [mm Hg]

1072 °C

1072 °C

Other Solid

A hard, silver-white metal [Argonne] Tarnishes on exposure to air; Melting point = 1074 degrees C; [Merck Index]

Samarium has high thermal neutron capture cross section ... has a low rate of burn off when used in control rods or in ceramics for radiation protection

Reasonably stable in air

Three crystal modifications of the metal exit, eith transformations at 734 and 922 °C

Ignites in air at 150 °C

For more Other Experimental Properties (Complete) data for Samarium, Elemental (8 total), please visit the HSDB record page.

This chemical does not meet GHS hazard criteria for 2.4% (6 of 255) of reports.

Danger

H228 (91%): Flammable solid [Danger Flammable solids]

P210, P231+P232, P240, P241, P280, P370+P378, P402+P404, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 255 reports by companies from 9 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Chemical: Samarium

Samarium is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Samarium 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: 10-11-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/23193

Samarium: Does not have an individual approval but may be used under an appropriate group standard

Most Important Radionuclide: Sm-151 Source: Fission product of uranium and plutonium; Half-Life: 90 years Specific Activity: 27 Ci/g Decay Mode: Beta GI Absorption: 0.05% Lung Clearance Half-Time: Weeks Internal Toxicity: High Annual Limit on Intake: 0.1 mCi Average Radiation Energy (MeV): Beta 0.020; Gamma <0.001; [Argonne] [See Glossary for references.] See Radiation, ionizing. See RARE EARTH METALS and linked occupational diseases.

Reacts with water to form explosive hydrogen gas. Can react violently with halogens. Potentially explosive reaction with 1,1,2-trichlorotrifluoroethane.

Material readily reacts with water generating flammable and/or explosive hydrogen gas /Samarium, Chip/

Contact with water liberates extremely flammable gases. Danger of cumulative effects. /Samarium powder/

A commercial mixer/mill was demolished and a technician was injured as a result of an explosion which occurred when an attempt was made to grind 20 g of samarium in approx 20 cc of 1,1,2-trichlorotrifluoroethane. Subsequent investigation revealed that the explosion was caused by the generation of fresh metal surface in the presence of the chlorinated halocarbon.

For more Hazardous Reactivities and Incompatibilities (Complete) data for Samarium, Elemental (6 total), please visit the HSDB record page.

Extinguishing Media. Suitable: Sand or dry powder type agents specially designed for metal powder fires. Use approved class D extinguishers or smother with dry sand, dry ground limestone, or dry clay. Unsuitable: Do not use water. Do not use halocarbon extinguishers. Firefighting. Protective Equipment: Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes. /Samarium powder/

Suitable extinguishing media: Carbon dioxide (CO2) Dry powder Extinguishing media which shall not be used for safety reasons: Water. Special protective equipment for fire-fighters: Wear self contained breathing apparatus for fire fighting if necessary.

Suitable: Sand or dry powder type agents specially designed for metal powder fires. Use approved class D extinguishers or smother with dry sand, dry ground limestone, or dry clay. Unsuitable: Do not use water. Do not use halocarbon extinguishers. /Samarium, Chip/

Protective Equipment: Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes. Specific Hazard(s): Emits toxic fumes under fire conditions. Liberates flammable/explosive hydrogen gas. /Samarium, Chip/

Keep container tightly closed in a dry and well-ventilated place. Store in cool place. Never allow product to get in contact with water during storage.

Suitable: Keep tightly closed. Special requirements: Air and moisture sensitive. Store under inert gas. /Samarium, Chip/

Handle as a radioactive spill. Evacuate area. Shut off all sources of ignition. Use nonsparking tools. /Samarium powder/

Accidental Release Measures. Personal precautions: Use personal protective equipment. Avoid dust formation. Avoid breathing dust. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Do not flush with water. Keep in suitable, closed containers for disposal.

Procedure to be followed in case of leak or spill: Handle as a radioactive spill. Personal Precautions: Wear self-contained breathing apparatus, rubber boots, and heavy rubber gloves. Methods for cleaning up: Sweep up, place in a bag and hold for waste disposal. Avoid raising dust. Ventilate area and wash spill site after material pickup is complete. /Samarium, Chip/

Material in the elemental state should be recovered for reuse or recycling. Observe all federal, state, and local environmental regulations. /Samarium, Chip/

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 quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

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

Keep away from heat/sparks/open flames/hot surfaces. - No smoking. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed. Take measures to prevent the build up of electrostatic charge.

Handle under inert gas. Protect from moisture.

Safety shower and eye bath. Use only in a chemical fume hood. /Samarium, Chip/

For more Preventive Measures (Complete) data for Samarium, Elemental (9 total), please visit the HSDB record page.

Samarium Stable Isotopes

(153)Samarium half-life = 46.27 hr, energy of decay: beta: 0.808 MeV (17.5%), 0.705 MeV (49.6%); gamma: 0.103 MeV (29.8%), 0.069 MeV (4.85%), 0.635 MeV (32.3%)

30 [mg/m3]

330 [mg/m3]

2000 [mg/m3]

Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face particle respirator type N100 (US) or type P3 (EN 143) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU). Hand protection: For prolonged or repeated contact use protective gloves. Eye protection: Safety glasses with side-shields conforming to EN166 Skin and body protection: Choose body protection according to the amount and concentration of the dangerous substance at the work place.

Respiratory: Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU). Where risk assessment shows air-purifying respirators are appropriate use a full-face particle respirator type N100 (US) or type P3 (EN 143) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Hand: Compatible chemical-resistant gloves. Eye: Chemical safety goggles. /Samarium, Chip/

LC50; Species: Hyalella azteca (Scud, young age 1-11 days); Conditions: freshwater, static, 24-25 °C, pH 7.39 (6.44-8.52), hardness 18 mg/L, alkalinity 14 mg/L CaCO3, conductivity 66 uS/sq cm (35-235 uS/sq cm), organic carbon 1.4 mg/L (0.7-3.6 mg/L); Concentration: 74 ug/L for 7 days (95% confidence interval: 57-95 ug/L) /Technical product/

LC50; Species: Hyalella azteca (Scud, young age 1-11 days); Conditions: freshwater, static, 24-25 °C, pH 8.21 (7.23-8.83), hardness 124 mg/L, alkalinity 84 mg/L CaCO3, conductivity 345 uS/sq cm (288-958 uS/sq cm), organic carbon 1.4 mg/L (0.7-3.6 mg/L); Concentration: 846 ug/L for 7 days (95% confidence interval: 603-1188 ug/L) /Technical product/

IDENTIFICATION AND USE: Elemental samarium is a rhobohedral silver metal. It is used as a neutron absorber, dopant for laser crystals, metallurgical research, and in permanent magnets. HUMAN EXPOSURE AND TOXICITY: Samarium metal may be harmful if absorbed through the skin, swallowed or inhaled. It may cause skin, respiratory tract, and eye irritation. ANIMAL STUDIES: Technical magnetic materials are increasingly used for the development of magnetic retained dental prosthetic and orofacial epithetic devices. Since most of the magnets based on rare earth metals, such as samarium-cobalt based alloys, have a high tendency for corrosion, they were first coated by tin and then encapsulated by titanium. However, the high mechanical load particularly on dental devices may cause a rupture of the titanium capsule and the alloys can contact directly biological fluids. The cytotoxicity of neodymium-iron-boron and samarium-cobalt (plain, tin and titanium coated) magnets was tested. First, magnets were incubated up to 7 days in culture medium to prepare extracts for cytotoxicity measurements. 3T3 mouse fibroblasts were cultured in the presence of extracts and their viability measured by neutral red and metabolic assays. 3T3 fibroblasts were also cultured in direct contact with the materials and material induced effects on cell morphology and growth monitored by microscopy. It was found that samarium-cobalt magnets have a strong tendency for corrosion and exert a considerable cytotoxicity.

Natural samarium is a mixture of seven isotopes, three of which are unstable but have long half-lives

Samarium is classified as a rare earth element. Rare earths are very similar within the group in chemical and physical properties. They are difficult to separate and always occur in nature in association with each other(1).

/ALTERNATIVE and IN VITRO TESTS/ Technical magnetic materials are increasingly used for the development of magnetic retained dental prosthetic and orofacial epithetic devices. Since most of the magnets based on rare earth metals, such as samarium-cobalt based alloys have a high tendency for corrosion they were first coated by tin and then encapsulated by titanium. However, the high mechanical load particularly on dental devices may cause a rupture of the titanium capsule and the alloys contact directly biological fluids ... The cytotoxicity of neodymium-iron-boron and samarium-cobalt (plain, tin and titanium coated) magnets was tested. First, magnets were incubated up to 7 days in culture medium to prepare extracts for cytotoxicity measurements ... 3T3 mouse fibroblasts were cultured in the presence of extracts and their viability measured by neutral red and metabolic assays. To learn more about a possible toxic activity of the main components of magnets, salt solutions of different concentrations resembling those elements, which are main constituents of the magnets, were used. 3T3 fibroblasts were also cultured in direct contact with the materials and material induced effects on cell morphology and growth monitored by microscopy. As a result of this study it was found that samarium-cobalt magnets have a strong tendency for corrosion and exert a considerable cytotoxicity ... Coating of samarium-cobalt magnets with tin or titanium makes the materials non-toxic ... /Samarium-cobalt magnets/

/ALTERNATIVE and IN VITRO TESTS/ The aim of this study was to assess and compare in vitro the cytotoxic effects of uncoated and parylene-coated rare earth magnets, used in orthodontics. Cytotoxicity of samarium-cobalt magnets (SmCo5 and Sm2Co17) and neodymium-iron-boron magnets (Nd2Fe14B) was assessed by two in vitro methods, the millipore filter method and an extraction method. Orthodontic stainless steel brackets served as controls. Uncoated SmCo5-magnets showed high cytotoxicity while uncoated Sm2Co17-magnets demonstrated moderate cytotoxicity. Uncoated neodymium-iron-boron magnets, as well as parylene coated Sm2Co17-magnets and parylene-coated neodymium-iron-boron magnets, showed negligible cytotoxicity. Short-term exposure to a static magnetic field did not cause any cytotoxic effect on the cells. /Samarium-cobalt magnets/

Rare earths exhibit ionic bonding. Samarium metal reacts at room temperature with oxygen or dry air relatively slowly; the reaction is rapid in moist air. It ignites in air at elevated temperatures and reacts with most nonmetallic elements. In dilute mineral acids, rapid dissolution takes place with the formation of samarium(+3) ions(1).

/SRP:/ 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 if necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on the 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. /Poisons A and B/

/SRP:/ 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 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 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 ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poisons A and B/

/SRP:/ 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 as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poisons A and B/

Used in control rods in nuclear reactors; Also used in alloys with cobalt to make strong permanent magnets; Occurs naturally along with other rare earth metals in the minerals monazite, bastnaesite, samarskite, cerite, orthite, ytterbite, and fluorspar; [Merck Index] There are 7 naturally-occurring isotopes with 3 of them being weakly radioactive with extremely long half-lives. There are 2 man-made radionuclides with long enough half-lives to be of concern as environmental contaminants. Sm-146 and Sm-151 are produced during nuclear fission of uranium and plutonium and have half-lives of 100,000,000 years and 90 years respectively. Used as a catalyst in organic chemistry, a pyrophoric metal in lighter flints, and a core in carbon arc-lamp electrodes; [Argonne]

Mining [Category: Industry]

Neutron absorber, dopant for laser crystals, metallurgical research, permanent magnets.

...used for carbon-arc lighting for the motion picture industry

High thermal neutron absorption cross-section and high melting point ... make /it/ ideal for use in nuclear control rod applications

Fabricated Metal Product Manufacturing

Samarium: ACTIVE

Samarium is a rare earth element that is extracted from natural ore materials such as mineral monazite and bastnasite. As such, the use of this material may require a radioactive materials license. It is recommended that you contact your state radiation protection program for guidance in this matter. Specifically, the samarium powder may be associated with sufficient concentrations of source material (e.g., uranium and thorium) that can result in having a licensable radioactive quantity.

While misch metal containing about 1% of samarium metal has long been used, samarium has not been isolated in relatively pure form until recently

Samarium forms chalcogenides which may exhibit a wide range of structural, electrical, and magnetic properties

Discovered along with europium in 1901 by de Marcay from the samarium fraction of didymium