Thorium Dioxide SDS

Revision Date: 01/30/2023


Product Identifiers

Product Name: Thorium Dioxide

Synonyms: Thorium oxide, thoria, thorianate

Formula: ThO2

CAS RN: [1314-20-1]

Identified Uses: Laboratory chemicals, manufacture of substances.


IBI Labs

3495 N. Dixie Hwy. Unit # 8

Boca Raton, FL 33431

Tel: 561-826-0061 Fax: 561-892-8450

Emergency Telephone Numbers


USA & Canada contact number: 1-800-535-5053

International contact number: 1-352-323-3500


Classification of The Substance or Mixture

GHS Classification in accordance with 29 CFR 1910 (OSHA HCS)

Acute toxicity, Oral (Category 3), H301

Acute toxicity, Inhalation (Category 3), H331

Acute toxicity, Dermal (Category 3), H311

Carcinogenicity (Category 1B), H350

Specific target organ toxicity – repeated exposure (Category 2), H373

For the full text of the H-Statements mentioned in this Section, see Section 16.

GHS Label elements, including precautionary statements:


Signal word: Danger

Hazard Statement

H301 + H311 + H331 Toxic if swallowed, in contact with skin, or if inhaled.

H350 May cause cancer.

H373 May cause damage to organs through prolonged, or repeated exposure.

Precautionary Statements

P201 Obtain special instructions before use.

P202 Do not handle until all safety precautions have been read and understood.

P260 Do not breathe dust/fume/gas/mist/vapors/spray.

P264 Wash skin thoroughly after handling.

P270 Do not eat, drink, or smoke when using this product.

P271 Use only outdoors, or in a well-ventilated area.

P280 Wear protective gloves/protective clothing.

P301 + P310 IF SWALLOWED: Immediately call a Poisson Center, or physician.

P302 + P352 IF ON SKIN: Wash with plenty of soap and water.

P304 + P340 IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing.

P308 + P313 IF exposed or concerned: Get medical advice and attention.

P322 Specific measures (see supplemental first aid instructions on this label).

P330 Rinse mouth.

P361 Remove all contaminated clothing.

P363 Wash contaminated clothing before reuse.

P403 + P233 Store in a well-ventilated place. Keep container tightly closed.

P405 Store locked up.

P501 Dispose of contents/container to an approved waste disposal plant.

Hazards not otherwise classified (HNOC) or not covered by GHS:



  • Molecular Formula: O2Th
  • Molecular Weight: 264.04 g/mol
  • EC-No.: 215-225-1
  • Appearance: White Powder
  • Solubility: Insoluble in water
  • Density, g/cm³: 9.86 g/cm³
  • Melting Point, °C: 3050°C
  • Boiling Point, °C: 4400°C
  • Stability: Stable under recommended storage conditions

Component Classification Concentration

Thorium Dioxide

Acute Tox. 3; Carc. 1B; STOT

RE 2; H301 + H311 + H331,

H350, H373

For the full text of the H-Statements mentioned in this section, see Section 14.


General advice:

  • Consult a physician.
  • Show this safety data sheet to the doctor in attendance.
  • Move out of dangerous area.

If inhaled:

  • If breathing, move person into fresh air.
  • If not breathing, give artificial respiration.
  • Consult a physician.

In case of skin contact:

  • Wash off with soap and plenty of water.
  • Take patient immediately to hospital.
  • Consult a physician.

In case of eye contact:

  • Flush eyes with water for at least 20 minutes.
  • Consult a physician.

If swallowed:

  • Never give anything by mouth to an unconscious person.
  • Rinse mouth with water.
  • Consult a physician.

The most important known symptoms and effects are described in the labelling (see section 2 and section 9).


Extinguishing Media

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical, or carbon dioxide.

Special hazards arising from the substance or mixture: Metal oxides.

Advice for firefighters: Wear self-contained breathing apparatus for firefighting if necessary.


Personal precautions, protective equipment, and emergency procedures:

  • Wear respiratory protection.
  • Avoid dust formation, breathing vapors, breathing dust, mist, or gas.
  • Ensure adequate ventilation.
  • Evacuate personnel to safe areas. 
  • For personal protection see section 8.

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.
  • Sweep up and shovel.
  • Keep in suitable, closed containers for disposal.


Precautions for safe handling:

  • Avoid contact with skin and eyes and formation of dust and aerosols.
  • Provide appropriate exhaust ventilation at places where dust is formed. 

Conditions for safe storage, including any incompatibilities:

  • Keep container tightly closed in a dry and well-ventilated place.
  • Keep in a dry place.

Specific end uses: Apart from the uses mentioned in section 1.2, no other specific uses are stipulated.


Control parameters:  Contains no substances with occupational exposure limit values.

Exposure controls:

  • Avoid contact with skin, eyes, and clothing.
  • Wash hands before breaks, and immediately after handling the product.

Personal Protective Equipment

Eye and face protection: Face shield and safety glasses Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).

Skin protection:

  • Handle with gloves.
  • Gloves must be inspected prior to use.
  • Use proper glove removal technique (without touching glove’s outer surface) to avoid skin contact with this product.
  • Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices.
  • Wash and dry hands.

Body protection: Complete suit protecting against chemicals, the type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.

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).

Control of environmental exposure:

  • Prevent further leakage or spillage if safe to do so.
  • Do not let product enter drains.



Possible human carcinogen.

IARC: No component of this product present at levels greater than or equal to 0.1% is identified as probable, possible, or confirmed human carcinogen by IARC.

ACGIH: No component of this product present at levels greater than or equal to 0.1% is identified as a carcinogen or potential carcinogen by ACGIH.

NTP: Known to be human carcinogen (Thorium dioxide).

OSHA: No component of this product present at levels greater than or equal to 0.1% is identified as a carcinogen or potential carcinogen by OSHA.

Reproductive toxicity:

Specific target organ toxicity – single exposure: No Data Available.

Specific target organ toxicity – repeated exposure: May cause damage to organs through prolonged or repeated exposure.

Aspiration hazard: No Data Available.

Additional Information

RTECS: No Data Available.

To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated.

Stomach: Irregularities based on Human Evidence.


Toxicity: No Data Available.

Persistence and degradability: No Data Available.

Bio-accumulative potential: No Data Available.

Mobility in soil: No Data Available.

Results of PBT and vPvB assessment: PBT/vPvB assessment not available as chemical safety assessment not required/not conducted.

Other adverse effects: No Data Available.


Waste treatment methods: Contact a licensed professional waste disposal service to dispose of this material. After use, follow local procedures for radioactive waste. Consult local, state, and federal regulations on the disposal of radioactive waste. Observe all federal, state, and local environmental regulations.

Contaminated packaging: Dispose of as unused product.


The U.S. Department of Transportation (D.O.T.) Code of Federal Regulations (49 CFR Parts 100-185), the International Air Transportation Association (IATA), International Civil Aviation Organization (ICAO) and International Maritime Organization (IMDG) are all factored into the classification and transport of material.

Proper Shipping Name:

Hazard Class:

UN/ID Number:                             To be determined on a case-by-case basis.

Special Information:

Packing Group:

Classification of substances with multiple hazards must be determined in accordance with the criteria presented in the regulations mentioned above. Due to the various quantities/combinations of materials being shipped at one time, the information above must be determined based on the characteristics of the specific shipment.


SARA 302 Components

SARA 302: No chemicals in this material are subject to the reporting requirements of SARA Title III, Section 302.

SARA 313 Components

The following components are subject to reporting levels established by SARA Title III, Section 313:

Thorium dioxide

CAS-No. 1314-20-1

Revision Date 1993-04-24

SARA 311/312 Hazards

Acute Health Hazard, Chronic Health Hazard.

Massachusetts Right to Know Components

Thorium dioxide

CAS-No. 1314-20-1

Revision Date 1993-04-24

Pennsylvania Right to Know Components

Thorium dioxide

CAS-No. 1314-20-1

Revision Date 1993-04-24

New Jersey Right to Know Components

Thorium dioxide

CAS-No. 1314-20-1

Revision Date 1993-04-24

California Prop. 65 Components

WARNING! This product contains a chemical known to the State of California to cause cancer.

Thorium dioxide

CAS-No. 1314-20-1

Revision Date 2007-09-28


Full text of H-Statements referred to under sections 2 and 3.

Acute Tox. Acute toxicity.

Carc. Carcinogenicity.

H301 Toxic if swallowed.

H301 + H311 +H331.

Toxic if swallowed, in contact with skin, or if inhaled.

H311 Toxic in contact with skin.

H331 Toxic if inhaled.

H350 May cause cancer.

HMIS Rating

Health hazard: 2.

Chronic Health Hazard: *.

Flammability: 0.

Physical Hazard 0.

NFPA Rating

Health hazard: 2.

Fire Hazard: 0.

Reactivity Hazard: 0.

Further information

Copyright 2014 IBI Labs. License granted to make unlimited paper copies for internal use only.

IBI Labs expects that recipients of their material are in compliance with 29 CFR 1910.1200(h) which requires employers to provide employees with effective information and training on hazardous chemicals in their work area.

The information and recommendations set forth herein are presented in good faith and believed to be correct as of the revision date. However, recipients of this material should use this information only as a supplement to other information gathered by them and should make independent judgement of the suitability and accuracy of this information. IBI Labs will not be liable for any special, indirect, incidental, or consequential damages, including but not limited to, loss of any kind whatsoever resulting from the use of the information provided in this Safety Data Sheet. IBI Labs expressly includes all warranties, expressed or implied, including warranties of merchantability and fitness for a particular purpose.

This information is furnished without warranty, and any use of the product not in conformance with this Safety Data Sheet, or in combination with any other product or process, is the responsibility of the user.


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