Thorium dioxide

  • Thoria
  • Thorianite
  • Thorium anhydride
  • Thorium oxide
  • Thorotrast
Formula
ThO2
Structure
Description
White powder.
Uses
Ceramics (high temp), gas mantles, nuclear fuel, flame spraying, crucibles, medicine, nonsilica optical glass, catalyst, thoriated tungsten filaments.

Registry Numbers and Inventories.
CAS
1314-20-1
EC (EINECS/ELINCS)
215-225-1
RTECS
XO6950000
RTECS class
Tumorigen; Human Data
UN (DOT)
2909
Merck
12,9518
Beilstein/Gmelin
141638 (G)
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
Korea ECL
Listed

Properties.
Formula
O2Th
Formula mass
264.04
Melting point, °C
3390
Boiling point, °C
4400
Density
10 g/cm3 (20 C)
Solubility in water
insoluble

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Do not touch damaged packages or spilled material. Cover liquid spill with sand, earth or other noncombustible absorbent material. Cover powder spill with plastic sheet or tarp to minimize spreading. Contact radiation safety officer.
Stability
No data.

Fire.
Fire fighting
If material involved in fire: Contact the local, state or department of energy radiological response team. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible.
Fire potential
May burn but does not ignite readily.

Health.
Carcinogin
N-1, CP65
Exposure effects
Supralethal radiation doses may result in headache, acute brain syndrome, alterations in mental status including coma, and (rarely) seizures within minutes of exposure. Prenatal ionizing radiation exposure may cause congenital anomalies, mental retardation, and an increased incidence of seizures.
   Ingestion
Gastrointestinal syndrome (nausea/vomiting) commonly occurs after doses of 9 to 20 gy and may occur following doses as low as 5 gy. Initial vomiting is followed by persistent diarrhea, which may be bloody.
   Inhalation
Pulmonary radiation injury may result in radiation pneumonitis and radiation pulmonary fibrosis.
   Skin
Thermonuclear burns may occur. If erythema is produced by a penetrating radiation, serious systemic injury is certain.
   Eyes
See Inhalation.

First aid
 
   Ingestion
Medical problems take priority over radiological concerns. Use first aid treatment according to the nature of the injury. Do not delay care and transport of a seriously injured person.
   Inhalation
Monitoring exposed patients for contamination and decontamination procedures should be started. All personnel involved in handling patients should wear disposable protective clothing. The patient should be completely undressed and given a soap and water bath or shower (if the patient's condition permits and if the facility exists). Acute inhalation of radionuclides presents some difficult problems.
   Skin
Immediately flush with running water for at least 20 minutes. See Ingestion.
   Eyes
Immediately flush with running water for at least 20 minutes. See Ingestion.

Transport.
UN number
2909
Response guide
Hazard class
7
USCG CHRIS Code
TDX