What's the MSDS of sodium metabisulfite

Material Safety Data Sheet

Sodium metabisulfite 

Section 1 - Chemical Product and Company Identification

MSDS Name: Sodium metabisulfite
Synonyms: Sodium pyrosulfite; Disodium disulfite; Pyrosulfurous acid, disodium salt; Disodium metabisulfite; Disodium pyrosulfite.
Company Identification:
 Rongda Chemical Co., Ltd
For information, call: +86 731-28813327
Emergency Number: +86 13617333142

Section 2 - Composition, Information on Ingredients



Chemical Name




Sodium metabisulfite




Section 3 - Hazards Identification



Appearance: white to yellow solid.
Danger! May cause allergic respiratory and skin reaction. May cause severe eye irritation and possible injury. May be harmful if swallowed. May cause skin and respiratory tract irritation. Contact with acids liberates toxic gas, sulfur dioxide. Slowly oxidized to the sulfate on exposure to air and moisture. Corrosive to aluminum in aqueous solution.
Target Organs: Respiratory system, eyes, skin.

Potential Health Effects 
Eye: May cause severe eye irritation and possible injury.
Skin: May cause skin irritation. May be harmful if absorbed through the skin. May cause an allergic reaction in certain individuals.
Ingestion: May cause gastrointestinal irritation with nausea, vomiting and diarrhea. May be harmful if swallowed. Sulfite compounds may cause a severe allergic reaction in sensitive individuals and some asthmatics. Sodium metabisulfite used as a preservative in vinegar provoked severe asthma in a 67-year-old woman who ate salad with vinegar-based dressing. (ACGIH Documentation of the TLVs)
Inhalation: May cause allergic respiratory reaction. May cause effects similar to those described for ingestion. Inhalation of dust may cause respiratory tract irritation.
Chronic: Prolonged or repeated skin contact may cause dermatitis. Repeated or prolonged exposure may cause allergic reactions in sensitive individuals.

Section 4 - First Aid Measures

Eyes: In case of contact, immediately flush eyes with plenty of water for a t least 15 minutes. Get medical aid immediately.
Skin: In case of contact, flush skin with plenty of water. Remove contaminated clothing and shoes. Get medical aid if irritation develops and persists. Wash clothing before reuse.
Ingestion: If swallowed, do not induce vomiting unless directed to do so by medical personnel. Never give anything by mouth to an unconscious person. Get medical aid.
Inhalation: If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
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. Substance is noncombustible.
Extinguishing Media: Use water fog, dry chemical, carbon dioxide, or regular foam.
Flash Point: Not applicable.
Autoignition Temperature: Not applicable.
Explosion Limits, Lower:Not available.
Upper: Not available.
NFPA Rating: (estimated) Health: 3; Flammability: 0; Instability: 0

Section 6 - Accidental Release Measures

General Information: Use proper personal protective equipment as indicated in Section 8.
Spills/Leaks: Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, observing precautions in the Protective Equipment section. Avoid generating dusty conditions. Provide ventilation.

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. Keep container tightly closed. Avoid breathing dust. Do not get in eyes. Avoid contact with skin and clothing.
Storage: Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from strong acids. Do not store in aluminum containers. Store protected from moisture. Keep away from oxidizing agents.

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 general or local exhaust ventilation to keep airborne concentrations below the permissible exposure limits.
Exposure Limits 

Chemical Name



OSHA - Final PELs

Sodium metabisulfite

5 mg/m3 TWA

5 mg/m3 TWA

none listed

Sulfur dioxide

2 ppm TWA; 5 ppm STEL

2 ppm TWA; 5 mg/m3 TWA 100 ppm IDLH

5 ppm TWA; 13 mg/m3 TWA

OSHA Vacated PELs: Sodium metabisulfite: 5 mg/m3 TWA Sulfur dioxide: 2 ppm TWA; 5 mg/m3 TWA
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 prevent skin exposure.
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 to yellow
Odor: sulfur dioxide odor
pH: acid in soln
Vapor Pressure: Not available.
Vapor Density: Not available.
Evaporation Rate:Not available.
Viscosity: Not available.
Boiling Point: Not available.
Freezing/Melting Point:150 deg C
Decomposition Temperature:150 deg C
Solubility: Soluble.
Specific Gravity/Density:1.4
Molecular Formula:Na2S2O5
Molecular Weight:190.11

Section 10 - Stability and Reactivity

Chemical Stability: Stable under normal temperatures and pressures. Slowly oxidized to the sulfate on exposure to air and moisture.
Conditions to Avoid: Dust generation, moisture, exposure to air, excess heat, Corrosive to aluminum in aqueous solution..
Incompatibilities with Other Materials: Strong oxidizing agents, acids.
Hazardous Decomposition Products: Oxides of sulfur, toxic fumes of sodium oxide.
Hazardous Polymerization: Has not been reported.

Section 11 - Toxicological Information

CAS# 7681-57-4: UX8225000      
CAS# 7446-09-5: WS4550000
CAS# 7681-57-4:
     Dermal, guinea pig: LD50 = >1 gm/kg;
     Draize test, rabbit, eye: 100 mg/24H Mild;
     Draize test, rabbit, skin: 500 mg;
     Oral, rat: LD50 = 1131 mg/kg;
     Skin, rat: LD50 = >2 gm/kg;

CAS# 7446-09-5:
     Draize test, rabbit, eye: 6 ppm/32D Mild;
     Inhalation, mouse: LC50 = 3000 ppm/30M;
     Inhalation, rat: LC50 = 2520 ppm/1H;
     Inhalation, rat: LC50 = 2168 mg/m3;

CAS# 7681-57-4: Not listed by ACGIH, IARC, NTP, or CA Prop 65.
CAS# 7446-09-5: Not listed by ACGIH, IARC, NTP, or CA Prop 65.

Epidemiology: Two cases of occupational asthma in laundry workers exposed to sodium metabisulfite were reported. Sodium metabisulfite may be considered to be the anhydride of sodium bisulfite and is the chief constituent of commercial dry sodium bisulfite.
Teratogenicity: No information found
Reproductive Effects: See actual entry in RTECS for complete information.
Mutagenicity: See actual entry in RTECS for complete information.
Neurotoxicity: No information found
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




Canada TDG

Shipping Name:

Not regulated

Not Regulated

Hazard Class:



UN Number:



Packing Group: