Selenium

  • C.I. 77805
Formula
Se
Structure
Description
Depending on allotropic form, the color can range from red to blue to greyto violet to black. Crystals
Uses
As ingredient of toning baths in photography, as pigment in manufacture ruby-, pink-, orange-, or red-colored glass, as metallic base in making electrodes for arc lights, electrical instruments & apparatus, as rectifier in radio & television sets, in selenium photocells, in semiconductor fusion mixtures, selenium cells.

Registry Numbers and Inventories.
CAS
7782-49-2
EC (EINECS/ELINCS)
231-957-4
EC Index Number
034-001-00-2
EC Class
Toxic; Danger of cumulative effects; Dangerous for the Environment
R 23/25 33 53
S 20/21 28 45 61
RTECS
VS7700000
RTECS class
Tumorigen; Reproductive Effector
UN (DOT)
2658
Merck
12,8572
Beilstein/Gmelin
8872 (G)
RCRA
D010
Swiss Giftliste 1
G-4552
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Korea ECL
Listed

Properties.
Formula
Se
Formula mass
78.96
Melting point, °C
217
Boiling point, °C
685
Vapor pressure, mmHg
0.0071 (25 C)
Density
4.28 g/cm3 (20 C)
Solubility in water
Insoluble
Viscosity
221 cp at 220C
Surface tension
105.5 g/s2 (220 C)
Refractive index
2.565
Dielectric constant
6.6 (20 C)
Thermal expansion
0.000412/K (30 C)
Heat of fusion
5.4 kJ/mol
Heat of vaporization
59.7 kj/mol
Heat of combustion
-2251 kJ/mol at 298 k

Hazards and Protection.
Storage
Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances.
Handling
Wash thoroughly after handling. Minimize dust generation and accumulation. Avoid contact with eyes, skin, and clothing. Avoid contact with skin and eyes. Keep container tightly closed. Avoid ingestion and inhalation. Use with adequate ventilation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Provide ventilation.
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents, acids, metal oxides, carbides, fluorine, oxygen, potassium.
Decomposition
Irritating and toxic fumes and gases, selenium/selenium oxides.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use extinguishing media appropriate to the surrounding fire. Substance is noncombustible. Extinguishing media: Substance is noncombustible; use agent most appropriate to extinguish surrounding fire. In case of fire use water spray, dry chemical, carbon dioxide, or chemical foam.
Fire potential
May burn but does not ignite readily.
Hazards
Containers may explode when heated. Runoff may pollute waterways. Substance may be transported in a molten form.
Combustion products
Hazardous decomposition products: Toxic gases and vapors may be released in a fire involving selenium.
Health
2
 
Flammability
0
 
 
Reactivity
0
 

Health.
Exposure limit(s)
OSHA PEL: TWA 0.2 mg/m3 NIOSH REL: TWA 0.2 mg/m3 *Note: PEL and REL also apply to other selenium compounds (as Se) except Selenium hexafluoride. NIOSH IDLH: 1 mg/m3 (as Se)
Poison_Class
1
Exposure effects
Prolonged or repeated skin contact may cause dermatitis. May cause reproductive and fetal effects. Chronic exposure to selenium may cause central nervous system effects, digestive tract disturbances, pallor, garlic breath, Chronic exposure to selenium may cause pallor, garlic breath, metallic taste, anemia, liver and spleen damage. Chronic selenium poisoning is characterized by loss of hair and nails, skin lesions, and abnormalities of the nervous system.
   Ingestion
May cause irritation of the digestive tract. May cause liver and kidney damage. May be harmful if swallowed. May cause alopecia (loss of hair). May cause spleen damage. May cause blood abnormalities. Effects may be delayed. May cause garlic smell on the breath and body.
   Inhalation
Causes respiratory tract irritation. May cause effects similar to those described for ingestion. May produce anemia, leucocytosis (increase in the white blood cell count) , cloudy swelling and fatty degeneration of the viscera.
   Skin
May cause skin irritation. Prolonged and/or repeated contact may cause irritation and/or dermatitis. May be absorbed through the skin. Contact with the skin may cause the skin to appear to be blue and the nails brittle and yellow.
   Eyes
Causes eye irritation. May result in corneal injury. May cause pink, puffy eyelids due to an allergic reaction.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If breathing is difficult, give oxygen. Get medical aid. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   Skin
Get medical aid. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed.

Transport.
UN number
2658
Response guide
Hazard class
6.1
Packing Group
III
 
USCG CHRIS Code
SEX
 
Std. Transport #
4925219