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Product Name: Sodium Biselenite
Chemical Formula: Na2Se2O5
CAS Number: 15578-64-4
Recommended Use: Laboratory reagent, chemical synthesis, industrial processing
Supplier Contact: Contact your chemical supplier for further details
Emergency Phone Number: Refer to local poison control and emergency services
Classification: Highly toxic when swallowed or inhaled, hazardous to environment, irritant to skin and eyes
GHS Label Elements: Skull and crossbones pictogram, corrosion pictogram, aquatic toxicity pictogram
Signal Word: Danger
Hazard Statements: Fatal if swallowed, causes severe skin burns and eye damage, may cause allergy or asthma symptoms, very toxic to aquatic life
Precautionary Statements: Avoid release to the environment, wear protective clothing and gloves, use respiratory protection, do not eat or drink when using, wash thoroughly after handling, store locked up
Main Component: Sodium Biselenite
Chemical Formula: Na2Se2O5
Concentration: > 98%
Impurities: May contain trace levels of metal contaminants from manufacturing sources
Other Ingredients: None listed
Inhalation: Remove exposed individual to fresh air immediately, provide artificial respiration if breathing stops, seek emergency medical attention without delay
Skin Contact: Rinse affected area with large volumes of water for at least 15 minutes, remove contaminated clothing and shoes, wash thoroughly with soap
Eye Contact: Rinse cautiously with water, keep eyelids open and continue rinsing for minimum 15 minutes, remove contact lenses if present and easy to do, seek urgent medical care
Ingestion: Do not induce vomiting, rinse mouth thoroughly, seek immediate medical attention, provide material details to medical personnel
Most Important Symptoms/Effects: Severe irritation, tissue burns, difficulty in breathing, nausea, dizziness, headache, potential systemic selenium toxicity
Suitable Extinguishing Media: Use water spray, dry chemical powder, or CO2 to extinguish flames
Specific Hazards: Thermal decomposition releases toxic selenium oxides and sodium oxides
Protective Equipment: Firefighters should wear self-contained breathing apparatus and full protective gear
Special Procedures: Cool exposed containers with water spray to prevent pressure buildup and rupture, contain runoff to avoid environmental contamination
Combustion Products: Selenium oxides, sodium oxides, possibly traces of hydrogen selenide
Personal Precautions: Evacuate non-essential personnel, ventilate area, wear appropriate protective equipment including respiratory protection, avoid dust formation
Environmental Precautions: Prevent entry into sewers or waterways, inform regulatory authorities if substance reaches water
Clean-up Procedures: Sweep up using approved tools, collect in appropriate containers for disposal, decontaminate area thoroughly with water and detergent, avoid generating dust
Handling: Work under chemical fume hood, wear gloves and goggles, avoid breathing vapors or dust, never eat, drink, or smoke in the workplace, wash hands after handling, ensure containers remain tightly closed
Storage: Store in cool, dry, well-ventilated area, segregated from incompatible materials such as acids and oxidizers, keep original tightly sealed packaging, label storage area as hazardous
Occupational Exposure Limits: Selenium compounds (as Se): OSHA PEL 0.2 mg/m3, ACGIH TLV 0.2 mg/m3
Engineering Controls: Use local exhaust ventilation, install air monitoring equipment, maintain negative pressure in work area
Personal Protective Equipment: Nitrile gloves, protective clothing, chemical splash goggles, full-face shield, NIOSH-approved respirators for selenium dust
Hygiene Measures: Remove contaminated clothing before leaving work area, wash hands and face thoroughly, provide eyewash stations and safety showers nearby
Appearance: White to off-white granular or crystalline powder
Odor: Odorless or faint metallic odor
Melting Point: Decomposes above 350°C
Solubility: Soluble in water
Density: Approximately 2.8 g/cm3
pH (solution): Slightly acidic to neutral (estimate 6-7)
Vapor Pressure: Negligible
Boiling Point: Not applicable — decomposes
Molecular Weight: 256.9 g/mol
Stability: Stable under recommended storage conditions
Reactivity: Reacts with strong acids releasing toxic selenium compounds
Incompatible Materials: Strong acids, strong oxidizers, reducing agents
Decomposition: Produces sodium oxide, selenium oxides, hydrogen selenide vapors under intense heat or acid conditions
Polymerization: Not expected to occur
Acute Toxicity: Highly toxic by oral and inhalation routes, oral LD50 (rat) estimated at 10 mg/kg
Chronic Toxicity: Long-term exposure may cause selenium accumulation, liver damage, neurological problems, hair/nail loss
Routes of Exposure: Inhalation, skin absorption, ingestion
Symptoms: Severe irritation of mucous membranes, respiratory distress, abdominal pain, vomiting, convulsions, eventual death in high doses
Carcinogenicity: Not classified as carcinogenic by IARC, NTP, or OSHA
Other Effects: Potential for allergic reactions or asthma-like symptoms
Ecotoxicity: Extremely toxic to aquatic organisms, long-lasting effects
Persistence and Degradability: Likely to persist in environment, may bioaccumulate in aquatic organisms and enter food chain
Mobility in Soil: Moderate to high, based on solubility and migration in water
Potential Environmental Impact: Selenium can cause acute and chronic toxicity to fish, birds, and livestock
Waste Disposal Methods: Dispose of contents and container in accordance with federal, state, and local regulations, use licensed chemical waste contractor
Incineration: Only in permitted facilities equipped to treat selenium emissions
Contaminated Packaging: Triple rinse and treat as hazardous waste, do not reuse packaging
Precautions: Never dispose of in sewage, water bodies, or regular landfill
UN Number: 3283
Proper Shipping Name: Selenium compound, n.o.s. (Sodium Biselenite)
Transport Hazard Class: 6.1 (Toxic substances)
Packing Group: II
Transport Labels: Toxic, keep away from foodstuffs
Special Precautions: Protect containers from physical damage and moisture during transit, transport by authorized carriers only, emergency response guides required
TSCA (US): Listed
REACH (EU): Subject to strict requirements as a hazardous substance
OSHA: Classified hazardous, workplace controls required
SARA 302/304: Extremely hazardous, subject to emergency planning notification
SARA 313: Reportable under toxic chemical release inventory
DSL (Canada): Listed
WHMIS Classification: D1A (very toxic), D2B (toxic), E (corrosive material)
