Material Safety Data Sheet (MSDS) for Dibenzyl Diselenide

Identification

Product Name: Dibenzyl Diselenide
Chemical Formula: C14H14Se2
CAS Number: 1508-82-3
Synonyms: Benzyl diselenide, Se-1,2-bis(phenylmethyl)diselenide
Recommended Use: Laboratory chemicals, chemical synthesis, research and development
Manufacturer/Supplier: Refer to label for supplier information
Contact Information: Emergency phone number for chemical emergencies can usually be found on the shipping documentation or product label
Emergency Overview: Organic selenium compound, can release toxic vapors in case of fire or thermal decomposition

Hazard Identification

GHS Classification: Acute toxicity (oral, inhalation, dermal), Skin irritant, Eye irritant, Specific target organ toxicity – repeated exposure
Hazard Pictograms: Skull and crossbones, Exclamation mark, Health hazard
Signal Word: Danger
Hazard Statements: Toxic if swallowed, in contact with skin or if inhaled; causes skin irritation; may cause organ damage through prolonged or repeated exposure
Precautionary Statements: Do not breathe dust or fumes; wash hands thoroughly after handling; use only outdoors or in well-ventilated area; wear protective gloves, clothing, eye protection, and face protection

Composition / Information on Ingredients

Chemical Name: Dibenzyl Diselenide
CAS Number: 1508-82-3
Concentration: 97-100%
Impurities: Minor organic impurities related to synthesis process, if any, typically under 3%

First Aid Measures

Inhalation: Move to fresh air, support breathing, avoid exposure to dust or vapors; if breathing problems arise, seek medical attention
Skin contact: Remove contaminated clothing; rinse skin thoroughly with plenty of water for at least 15 minutes; wash with soap and water; medical attention if irritation persists
Eye contact: Rinse eye(s) carefully with water for several minutes; remove contact lenses; continue rinsing; seek medical advice if symptoms continue
Ingestion: Rinse mouth with water, never give anything by mouth to an unconscious person; seek medical attention immediately; do not induce vomiting unless instructed by healthcare provider
Important Symptoms/Effects: Nausea, respiratory difficulty, skin and eye irritation, potential central nervous system depression with high exposure, headache, or confusion
Notes to Physician: Monitor for selenium poisoning, provide supportive care, consider symptomatic treatment

Fire-Fighting Measures

Suitable Extinguishing Media: Use dry chemical, carbon dioxide, or foam; water spray for larger fires; avoid direct water stream on burning chemical
Special Hazards from Chemical: Thermal decomposition produces toxic gases including selenium oxides, carbon monoxide, and carbon dioxide; releases irritating and possibly corrosive fumes
Advice for Firefighters: Wear self-contained breathing apparatus (SCBA), full protective clothing; evacuate area; prevent runoff from entering drains; do not attempt to fight fire without proper training
Flammability: Combustible solid, may ignite at elevated temperatures or through friction
Explosion Hazard: Warning for fine dust-air mixtures in confined spaces

Accidental Release Measures

Personal Precautions: Wear protective equipment including gloves, lab coat, safety goggles, NIOSH-approved respirator if dust or fumes present; avoid contact with skin, eyes, and clothing
Environmental Precautions: Prevent further leakage or spillage; do not allow material to enter watercourses, sewers, or drains
Methods for Containment and Cleanup: Sweep up spill using non-sparking tools, avoid dust formation; place in a suitable, properly labeled container for recovery or disposal; ventilate area; decontaminate surfaces with suitable detergent and water
Decontamination: Avoid using bleach or oxidizing cleaning agents; dispose of cleaning materials as hazardous waste

Handling and Storage

Handling: Keep container tightly closed; use only in well-ventilated area; avoid generating dust; do not breathe dust or vapors; avoid contact with skin, eyes, and clothing; wash thoroughly after handling; keep away from sources of ignition
Storage: Store in a cool, dry, well-ventilated area away from incompatible substances such as strong oxidizers and acids; keep container well-sealed and labeled; avoid excessive heat and direct sunlight
Special Packaging Requirements: Use corrosion-resistant packaging; inspect regularly for signs of leaks or degradation

Exposure Controls and Personal Protection

Occupational Exposure Limits: Selenium compounds (as Se): OSHA PEL 0.2 mg/m³ (TWA); ACGIH TLV 0.2 mg/m³ (TWA)
Engineering Controls: Use laboratory fume hood or local exhaust ventilation for handling powders, vapors, or solutions; safety shower and eyewash stations should be accessible
Personal Protective Equipment: Nitrile or neoprene gloves, chemical splash goggles, face shield, flame-retardant lab coat or apron, appropriate NIOSH-certified respirator when exposure risk is significant
Hygiene Measures: Prohibit eating, drinking, and smoking in handling areas; wash hands thoroughly before breaks and after handling

Physical and Chemical Properties

Appearance: Yellow to orange crystalline powder
Odor: Mild, often described as musty or garlicky – characteristic of many organoselenium compounds
Melting Point: 108–110 °C
Boiling Point: Data not available due to decomposition before boiling
Solubility: Soluble in common organic solvents such as chloroform, benzene, and ether; limited solubility in water
Vapor Pressure: Very low at ambient conditions
Density: ~1.37 g/cm³ at 20 °C
pH: Not applicable (non-aqueous solid)
Partition Coefficient (log Kow): Estimated to be above 3, indicates significant bioaccumulation potential
Other Properties: Not volatile at room temperature, may decompose under strong light or prolonged exposure to heat, emits toxic fumes under combustion

Stability and Reactivity

Chemical Stability: Stable under normal conditions if kept dry and protected from light
Incompatible Materials: Strong oxidizing agents, strong acids, peroxides, halogens
Hazardous Decomposition Products: Selenium oxides, benzyl derivatives, carbon monoxide, carbon dioxide
Polymerization: Hazardous polymerization does not occur
Conditions to Avoid: Heat, open flame, exposure to light, contact with incompatible materials
Reactivity: Can react vigorously with oxidizing agents or under strong acidic conditions to produce hazardous gases

Toxicological Information

Pertinent Routes of Exposure: Inhalation, ingestion, skin, and eye contact
Acute Toxicity: High oral and respiratory toxicity (LD₅₀ oral rat: 116 mg/kg, based on comparable selenium compounds)
Skin Corrosion/Irritation: May cause skin burns or dermatitis
Eye Damage/Irritation: Causes moderate to severe irritation, redness, or watering
Respiratory Effects: Inhalation of dust or fumes may cause headache, dizziness, cough, and respiratory tract irritation
Chronic Effects: Prolonged or repeated exposure can lead to selenium accumulation in body, selenosis, symptoms include hair loss, fatigue, garlic breath, irritability, and neurological disorders
Sensitization: Possible skin sensitizer; limit exposure
Carcinogenicity/Mutagenicity: Not classified as a carcinogen by IARC, NTP, or OSHA, but chronic overexposure to selenium compounds carries risk; no reliable data on mutagenicity or teratogenicity for this specific compound, precaution advised

Ecological Information

Toxicity to Aquatic Life: Highly toxic to aquatic organisms, especially fish and invertebrates; LC₅₀ for some species below 1 mg/L based on organoselenium chemical class
Persistence and Degradability: Biodegradation data not available, structurally stable compound, may persist in environment; selenides can transform into more bioavailable forms under certain conditions
Bioaccumulation Potential: High log Kow suggests potential for bioaccumulation in wildlife and aquatic food chains
Mobility in Soil: Limited mobility, but may migrate with organic phase in subsurface environments
Other Effects: Selenium compounds biomagnify, raising concerns for birds, aquatic life, and secondary consumers; regulatory scrutiny applies in many jurisdictions

Disposal Considerations

Waste Treatment Methods: Collect and place residue and contaminated materials in designated chemical waste container; disposal must be through a licensed hazardous waste handler
Special Precautions: Never pour into drain, surface water, or on soil; neutralize or stabilize, if possible, within permitted guidelines
Disposal Regulations: Abide by all local, regional, national, and international regulations for disposal of selenium-containing compounds; indicate selenium-containing organic waste in disposal documentation
Container Disposal: Triple rinse empty containers with suitable solvent, offer for recycling or reconditioning if authorized, puncture and dispose of as hazardous waste if not reusable

Transport Information

UN Number: Not assigned specifically for Dibenzyl Diselenide; may be shipped under UN3283, Selenium compound, solid, n.o.s.
Proper Shipping Name: Selenium compound, solid, n.o.s.
Transport Hazard Class: Class 6.1 (Toxic substances)
Packing Group: III
Hazard Label: Toxic/Poison label required
Environmental Hazards: Marked as environmentally hazardous substance for maritime and ground transport
Transport in Bulk: Not recommended; follow all special precautions listed on shipping documents
Special Transport Precautions: Avoid packaging damage, keep products upright and securely contained throughout transit

Regulatory Information

OSHA Status: Classified hazardous under OSHA Hazard Communication Standard (29 CFR 1910.1200)
TSCA Inventory: Listed
SARA Title III: Not specifically listed; general reporting for selenium may apply; consult Sections 302, 304, 311, 312, and 313
RCRA Code: U205 (for selenium-containing waste; check local list)
CERCLA Reportable Quantity: 1 lb (for elemental selenium and some selenium compounds)
Canadian WHMIS Classification: D1B (toxic), D2B (irritant)
REACH (EU): Pre-registered and subject to authorisation/notification under current annexes for selenium organics
Other International Regulation: Subject to IATA/ICAO and IMDG requirements for toxic solids; some countries may require special labeling for persistent bioaccumulative toxic chemicals