Barium

Agent Name
Barium
Alternative Name
Barium and soluble compounds
CAS Number
7440-39-3; varies
Formula
Ba, varies
Major Category
Metals
Synonyms
Elemental barium; Barium metal; Barium, elemental; [CHEMINFO] UN1400
Category
Metals, Inorganic Compounds
Description
Elemental barium: a silver to white metallic solid; [CAMEO]
Sources/Uses
"The largest end use of barium is as a "getter" to remove the last traces of gases from vacuum and television picture tubes. It is also used to improve performance of lead alloy grids of acid batteries, as a component of grey and ductile irons, and in the manufacture of steel, copper and other metals." [HSDB]
Comments
The soluble salts are toxic: acetate, chloride, hydroxide, oxide, nitrate, and (poly)sulfide. Insoluble salts are rarely toxic: arsenate, chromate, fluoride, oxalate, and sulfate. In the gastric acid of the stomach, barium carbonate (insoluble) converts into barium chloride (soluble). Signs of barium poisoning are abdominal cramping, severe hypokalemia, and paralysis within 2 hours of ingestion. [Goldfrank, p. 1434-5] Concentrated solutions of barium oxide or barium hydroxide are strongly alkaline and corrosive to the skin and eyes. Soluble barium ion is a muscle poison that can cause respiratory arrest and ventricular fibrillation with a lethal dose of about 3-4 g. when absorbed by the gut. [ACGIH] A study of welders using consumable electrodes with high barium content 4 hours daily showed high levels of barium in the urine, but no discernable health effects. [Reference #1] Ingestion of soluble barium compounds in high doses may induce acute renal failure. [Rosenstock, p. 575]
Biomedical References

Exposure Assessment

Skin Designation (ACGIH)
Insufficient data
TLV (ACGIH)
0.5 mg/m3, as Ba
PEL (OSHA)
0.5 mg/m3, as Ba
MAK
0.5 mg/m3, as Ba, inhalable fraction (soluble compds)
IDLH (NIOSH)
50 mg/m3, as Ba
Excerpts from Documentation for IDLHs
Human data: It has been reported that the lethal oral dose is 43 to 57 mg Ba/kg [Reeve 1979]. [Note: An oral dose of 43 to 57 mg Ba/kg is equivalent to a 70-kg worker being exposed to 2,007 to 2,660 mg/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]
Half Life
Blood: 18 hours (1.9 hours with hemodialysis); whole body: few days; [TDR, p. 145]
Reference Link #2

Adverse Effects

Nephrotoxin
Yes
ACGIH Carcinogen
Not Classifiable

Diseases, Processes, and Activities Linked to This Agent

Activities

Activities with risk of exposure: