Material Safety Data Sheet
Sodium thiosulfate

ACC# 21710
Section 1 - Chemical Product and Company Identification

MSDS Name: Sodium thiosulfate
Catalog Numbers: AC202870000, AC202870010, AC202870025, AC202870050, AC202875000, S75222, S78930-1, S78930-2, S78930-3, S78930-4, S79809, NC9417189, S446-3, S446-500, S446-500LC
Sodium Hyposulfite; Sodium Oxide Sulfide; Thiosulfuric Acid Disodium Salt
Company Identification:

              Fisher Scientific
              1 Reagent Lane
              Fair Lawn, NJ 07410
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Section 2 - Composition, Information on Ingredients

CAS# Chemical Name Percent EINECS/ELINCS
7772-98-7 Sodium thiosulfate >98 231-867-5

Section 3 - Hazards Identification


Appearance: white solid.
Caution! May cause eye, skin, and respiratory tract irritation. Hygroscopic (absorbs moisture from the air).
Target Organs: No data found.

Potential Health Effects
Eye: May cause eye irritation.
Skin: May cause skin irritation. May be harmful if absorbed through the skin.
Ingestion: May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May be harmful if swallowed.
Inhalation: May cause respiratory tract irritation. May be harmful if inhaled.
Chronic: No information found.

Section 4 - First Aid Measures

Eyes: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.
Skin: Flush skin with plenty of water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists.
Ingestion: If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid.
Inhalation: Remove from exposure and move to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid if cough or other symptoms appear.
Notes to Physician: Treat symptomatically and supportively.

Section 5 - Fire Fighting Measures

General Information: As in any fire, 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.
Extinguishing Media: Use water spray, dry chemical, or carbon dioxide.
Flash Point: Not available.
Autoignition Temperature: Not available.
Explosion Limits, Lower:Not available.
Upper: Not available.
NFPA Rating: (estimated) Health: 1; Flammability: 0; Instability: 1

Section 6 - Accidental Release Measures

General Information: Use proper personal protective equipment as indicated in Section 8.
Spills/Leaks: Sweep up, then place into a suitable container for disposal. Avoid generating dusty conditions.

Section 7 - Handling and Storage

Handling: Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with skin and eyes. Keep container tightly closed. Avoid ingestion and inhalation.
Storage: Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from strong acids.

Section 8 - Exposure Controls, Personal Protection

Engineering Controls: Facilities storing or utilizing this material should be equipped with an eyewash facility and a safety shower. Use adequate ventilation to keep airborne concentrations low.
Exposure Limits
Chemical Name ACGIH NIOSH OSHA - Final PELs
Sodium thiosulfate none listed none listed none listed

OSHA Vacated PELs: Sodium thiosulfate: No OSHA Vacated PELs are listed for this chemical.
Personal Protective Equipment
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 minimize contact with skin.
Respirators: Follow the OSHA respirator regulations found in 29 CFR 1910.134 or European Standard EN 149. Use a NIOSH/MSHA or European Standard EN 149 approved respirator if exposure limits are exceeded or if irritation or other symptoms are experienced.

Section 9 - Physical and Chemical Properties

Physical State: Solid
Appearance: white
Odor: odorless
pH: 6.5-8 (solution)
Vapor Pressure: Negligible.
Vapor Density: Not applicable.
Evaporation Rate:negligible
Viscosity: Not available.
Boiling Point: Not available.
Freezing/Melting Point:43 deg C
Decomposition Temperature:Not available.
Solubility: Soluble.
Specific Gravity/Density:1.66
Molecular Formula:Na2O3S2
Molecular Weight:158.0978

Section 10 - Stability and Reactivity

Chemical Stability: Stable under normal temperatures and pressures. Deliquescent (tending to absorb atmospheric water vapor and become liquid).
Conditions to Avoid: High temperatures, moisture.
Incompatibilities with Other Materials: Strong acids.
Hazardous Decomposition Products: Oxides of sulfur, hydrogen sulfide, sodium oxide.
Hazardous Polymerization: Has not been reported.

Section 11 - Toxicological Information

CAS# 7772-98-7: XN6476000
Not available.

CAS# 7772-98-7: Not listed by ACGIH, IARC, NTP, or CA Prop 65.

Epidemiology: No information available.
Teratogenicity: No information available.
Reproductive Effects: No information available.
Mutagenicity: Please refer to RTECS# XN6476000 for specific information.
Neurotoxicity: No information available.
Other Studies:

Section 12 - Ecological Information

No information available.

Section 13 - Disposal Considerations

Chemical waste generators must determine whether a discarded chemical is classified as a hazardous waste. US EPA guidelines for the classification determination are listed in 40 CFR Parts 261.3. Additionally, waste generators must consult state and local hazardous waste regulations to ensure complete and accurate classification.
RCRA P-Series: None listed.
RCRA U-Series: None listed.

Section 14 - Transport Information

Shipping Name: Not Regulated Not Regulated
Hazard Class:
UN Number:
Packing Group:

Section 15 - Regulatory Information


     CAS# 7772-98-7 is listed on the TSCA inventory.
Health & Safety Reporting List
     None of the chemicals are on the Health & Safety Reporting List.
Chemical Test Rules
     None of the chemicals in this product are under a Chemical Test Rule.
Section 12b
     None of the chemicals are listed under TSCA Section 12b.
TSCA Significant New Use Rule
     None of the chemicals in this material have a SNUR under TSCA.
CERCLA Hazardous Substances and corresponding RQs
     None of the chemicals in this material have an RQ.
SARA Section 302 Extremely Hazardous Substances
     None of the chemicals in this product have a TPQ.
Section 313      No chemicals are reportable under Section 313.
Clean Air Act:
     This material does not contain any hazardous air pollutants.
     This material does not contain any Class 1 Ozone depletors.
     This material does not contain any Class 2 Ozone depletors.
Clean Water Act:
     None of the chemicals in this product are listed as Hazardous Substances under the CWA.
     None of the chemicals in this product are listed as Priority Pollutants under the CWA.
     None of the chemicals in this product are listed as Toxic Pollutants under the CWA.
     None of the chemicals in this product are considered highly hazardous by OSHA.
     CAS# 7772-98-7 is not present on state lists from CA, PA, MN, MA, FL, or NJ.

California Prop 65

California No Significant Risk Level: None of the chemicals in this product are listed.

European/International Regulations

European Labeling in Accordance with EC Directives
Hazard Symbols:
      Not available.
Risk Phrases:

Safety Phrases:

     S 24/25 Avoid contact with skin and eyes.

WGK (Water Danger/Protection)

     CAS# 7772-98-7: 0
Canada - DSL/NDSL
     CAS# 7772-98-7 is listed on Canada's DSL List.
Canada - WHMIS
     This product has a WHMIS classification of Not controlled..
This product has been classified in accordance with the hazard criteria of the Controlled Products Regulations and the MSDS contains all of the information required by those regulations.
Canadian Ingredient Disclosure List

Section 16 - Additional Information

MSDS Creation Date: 12/12/1997
Revision #5 Date: 2/12/2007

The information above is believed to be accurate and represents the best information currently available to us. However, we make no warranty of merchantability or any other warranty, express or implied, with respect to such information, and we assume no liability resulting from its use. Users should make their own investigations to determine the suitability of the information for their particular purposes. In no event shall Fisher be liable for any claims, losses, or damages of any third party or for lost profits or any special, indirect, incidental, consequential or exemplary damages, howsoever arising, even if Fisher has been advised of the possibility of such damages.