Material Safety Data Sheet: Dimethyl Disulfide

Identification

Product Name: Dimethyl Disulfide
Synonyms: DMDS, Methyl disulfide
CAS Number: 624-92-0
Molecular Formula: C2H6S2
Recommended Use: Industrial chemical, intermediate, solvent, soil fumigant
Supplier: [Supplier Name, Address, Phone]
Emergency Contact: [Emergency phone number]

Hazard Identification

GHS Classification: Flammable liquid (Category 3), Acute toxicity (oral, Category 4), Skin irritation (Category 2), Eye irritation (Category 2), Specific target organ toxicity – single exposure (Category 3), Hazardous to aquatic environment (Acute/Chronic: Category 2)
Signal Word: Warning
Hazard Statements: Flammable liquid and vapor; Harmful if swallowed; Causes skin irritation; Causes eye irritation; May cause respiratory irritation; Toxic to aquatic life
Pictograms: Flame, Exclamation mark, Environment
Precautionary Statements: Keep away from heat/sparks/open flames; Do not breathe vapors; Wear protective gloves and eye protection; Wash hands thoroughly after handling; Avoid release to environment

Composition / Information on Ingredients

Chemical Name: Dimethyl Disulfide
Common Name: Methyl disulfide
Concentration: ≥99%
Other Components: None significant

First Aid Measures

Inhalation: Remove to fresh air immediately; provide oxygen if breathing is difficult; seek medical attention
Skin Contact: Wash with plenty of soap and water; remove contaminated clothing; get medical help if irritation develops
Eye Contact: Rinse cautiously with water for several minutes; remove contact lenses if present and easy to do; continue rinsing; get medical help
Ingestion: Rinse mouth; do NOT induce vomiting; give water to drink if person is conscious; seek immediate medical advice

Fire-Fighting Measures

Suitable Extinguishing Media: Water spray, carbon dioxide, foam, dry chemical
Unsuitable Extinguishing Media: Direct water jet
Special Hazards: Vapors may form explosive mixtures with air; toxic gases (sulfur oxides, carbon oxides) may be released; containers may explode in heat
Firefighter Protection: Full protective clothing and self-contained breathing apparatus; cool containers with water fog to prevent pressure build-up and explosion; avoid inhalation of hazardous decomposition products

Accidental Release Measures

Personal Precautions: Evacuate unnecessary personnel; wear protective equipment (gloves, goggles, mask); avoid inhalation of vapors
Environmental Precautions: Prevent spillage from entering soil, waterways, drains, sewers
Containment and Clean-Up: Stop leak if safe; absorb with inert material such as sand or earth; scoop up and collect in suitable containers for disposal; ventilate area; wash spill site with water after material pick-up is complete

Handling and Storage

Handling: Use only in well-ventilated areas; keep away from sources of ignition; take measures against static discharge; do not breathe vapors or mist; avoid contact with skin or eyes; use spark-proof tools and explosion-proof equipment
Storage: Store tightly closed in cool, dry, well-ventilated place; keep away from heat, sparks, open flames; store away from oxidizing agents, acids, and bases; store in containers labeled and suitable for flammable liquid; segregate from food and feed

Exposure Controls and Personal Protection

Exposure Limits: Occupational Exposure Limit (OEL) not established locally; consult country-specific limits where available
Engineering Controls: Mechanical exhaust required; local ventilation to control vapor concentrations
Personal Protective Equipment: Impervious gloves (e.g., nitrile); chemical splash goggles; protective clothing; in case of inadequate ventilation, use approved respirators
Hygiene Measures: Wash hands and face after handling; remove contaminated clothing and wash before reuse; do not eat or drink in work area

Physical and Chemical Properties

Appearance: Colorless to pale yellow liquid
Odor: Strong, unpleasant, sulfurous (garlic-like)
Odor Threshold: Approximately 0.1 ppm
pH: Not applicable
Melting Point/Freezing Point: -85°C
Boiling Point: 109°C
Flash Point: 18°C (64°F; closed cup)
Evaporation Rate: Not determined
Flammability: Flammable
Upper/Lower Flammability or Explosive Limits: Lower 1.1%; Upper 18.5% (V)
Vapor Pressure: 24 mmHg at 25°C
Vapor Density (air=1): 2.7
Relative Density: 1.062 at 20°C
Solubility: Slightly soluble in water (3.1 g/L at 20°C); miscible with most organic solvents
Partition Coefficient (n-octanol/water): 1.77
Auto-Ignition Temperature: 215°C
Decomposition Temperature: Not determined
Viscosity: 0.47 mPa·s at 25°C
Molecular Weight: 94.2 g/mol
Explosive Properties: Vapor-air mixtures may be explosive
Oxidizing Properties: Not an oxidizer

Stability and Reactivity

Chemical Stability: Stable under recommended storage and handling conditions
Reactivity: Reacts with strong oxidizers, acids, bases
Hazardous Reactions: May react exothermically with oxidants, producing heat and hazardous gases
Conditions to Avoid: Heat, sparks, open flames, static discharge
Incompatible Materials: Oxidizing agents, acids, alkalis
Hazardous Decomposition Products: Toxic fumes of sulfur oxides, carbon oxides, methane, hydrogen sulfide

Toxicological Information

Acute Toxicity: LD50 (oral, rat): 190 mg/kg; LC50 (inhalation, rat): 240 ppm (4h)
Skin Corrosion/Irritation: Causes irritation, redness, possible burns on prolonged contact
Serious Eye Damage/Irritation: Causes irritation, redness, tearing
Respiratory Sensitization: Inhalation may cause respiratory tract irritation; coughing, shortness of breath, dizziness
Skin Sensitization: Not classified as a skin sensitizer
Germ Cell Mutagenicity: Not classified as mutagenic
Carcinogenicity: Not listed as carcinogen by IARC, NTP, ACGIH, OSHA
Reproductive Toxicity: No available evidence of reproductive or developmental toxicity
STOT – Single Exposure: May cause drowsiness or dizziness
STOT – Repeated Exposure: Prolonged exposure may affect central nervous system, liver, kidneys
Aspiration Hazard: Not classified as an aspiration hazard

Ecological Information

Ecotoxicity: Toxic to aquatic life; LC50 (fish, 96h): ~1-10 mg/L; EC50 (daphnia, 48h): 0.5 mg/L
Persistence and Degradability: Biodegradable under aerobic conditions, but degrades slowly
Bioaccumulative Potential: Moderate potential; log Kow: 1.77
Mobility in Soil: Expected to have moderate mobility; tends to volatilize from moist soil
Other Adverse Effects: May contribute to local pollution if released; avoid direct release to environment

Disposal Considerations

Waste Disposal: Recycle or dispose of in compliance with local, regional, and national regulations; avoid landfill disposal
Contaminated Packaging: Empty containers should be cleaned with solvent, then can be recycled or incinerated with proper authority
Environmental Precautions: Prevent substance from entering drains, sewers, or water courses; inform relevant authorities in case of large spill

Transport Information

UN Number: 2381
UN Proper Shipping Name: Dimethyl disulfide
Transport Hazard Class: 3 (Flammable liquids)
Packing Group: II
Labels: Flammable liquid
Special Precautions: Avoid transport with food or feed; keep containers tightly closed
Marine Pollutant: Yes

Regulatory Information

US TSCA: Listed
EU REACH: Registered
OSHA: Hazardous
SARA Title III: Section 313 – Not subject
Canadian WHMIS: Class B, D2B
Other Relevant Regulations: Follow applicable local, federal, and national chemical regulations; compliance with workplace safety, environmental, and transport laws required