© 2026 Alchemist Worldwide Ltd,
All Right Reserved
Chemical Name: Sodium Selenite
Synonyms: Disodium selenite, selenious acid disodium salt
CAS Number: 10102-18-8
Recommended Use: Laboratory chemicals, manufacturing, nutritional supplement in animal feed
Manufacturer: Name, address, emergency phone number provided on request
Product Code: As assigned by supplier
Emergency Phone: Refer to local poison center or manufacturer’s hotline
Uses Advised Against: Direct skin contact, inhalation, ingestion without proper controls
Classification: Acute toxicity (oral, dermal, inhalation); Environmental hazard (aquatic, acute and chronic)
Label Elements: Skull and crossbones pictogram, exclamation mark pictogram, environmental hazard pictogram
Signal Word: Danger
Hazard Statements: Toxic if swallowed, in contact with skin, or if inhaled. May cause genetic defects. Very toxic to aquatic life.
Precautionary Statements: Avoid all exposure, wear proper personal protection, do not breathe dust or vapors, wash thoroughly after handling, prevent release into environment.
Routes of Exposure: Inhalation, ingestion, dermal absorption
Symptoms of Exposure: Nausea, vomiting, diarrhea, garlic breath odor, irritability, fatigue, skin redness, lung irritation at high exposures
Chemical Name: Sodium Selenite
CAS Number: 10102-18-8
Concentration: 100% (unless diluted)
Impurities: Typically none in reagent grade
Molecular Formula: Na2SeO3
Molecular Weight: 172.94 g/mol
General Advice: Remove individual from hazard zone immediately, seek medical advice
Inhalation: Move to fresh air, monitor respiratory distress, provide oxygen if needed, seek prompt medical attention
Skin Contact: Remove contaminated clothing, flush exposed skin under running water for at least 15 minutes
Eye Contact: Rinse opened eye slowly under lukewarm, gently flowing water for at least 15 minutes, then seek medical evaluation
Ingestion: Do not induce vomiting, rinse mouth, offer small amount of water if conscious, seek emergency medical help
Most Important Symptoms and Effects: Severe mucous membrane irritation, nausea, neurological effects, respiratory distress
Suitable Extinguishing Media: Water spray, dry chemical, carbon dioxide, foam
Hazardous Combustion Products: Emits toxic fumes of selenium and sodium oxide
Protective Equipment: Firefighters wear self-contained breathing apparatus and full protective gear
Special Hazards: Material may form irritating or toxic gases if involved in a fire, runoff may cause environmental contamination
Special Procedures: Move containers from fire area if safe to do so, prevent firewater from entering waterways
Spill Response: Evacuate unnecessary personnel, ventilate area, avoid dust formation
Personal Precautions: Wear respirator, chemical-resistant gloves, goggles, lab coat
Environmental Precautions: Prevent spilled product from entering sewers, surface or groundwater
Cleanup Methods: Collect spilled material mechanically, place in suitable labeled containers for proper disposal, wash area thoroughly with water, ventilate
Handling Precautions: Work with adequate ventilation, avoid any contact with eyes, skin, and clothing
Safe Handling Advice: Do not inhale dusts, do not eat or drink while handling, avoid spills and splashes
Storage Requirements: Store in a tightly closed container in cool, dry, well-ventilated place away from incompatible substances
Incompatibles: Strong acids, strong oxidizers, reducing agents
Special Sensitivity: Moisture and light accelerate decomposition; use dry, dark storage
Technical Measures: Use chemical fume hood; ensure eye-wash and safety shower stations nearby
Exposure Limits: OSHA PEL (Selenium compounds): 0.2 mg/m³ TWA; ACGIH TLV: 0.2 mg/m³ TWA
Engineering Controls: Chemical fume hood, mechanical exhaust, containment
Personal Protection: Safety glasses with side shields, impervious gloves (nitrile recommended), chemical-resistant clothing
Respiratory Protection: Approved particulate respirator in absence of adequate ventilation
Hygiene Measures: Wash hands thoroughly after handling, keep contaminated clothing separate, launder before reuse
Appearance: White or colorless, crystalline solid or powder
Odor: Odorless
Solubility: Soluble in water
Melting Point: Decomposes at approximately 710 °C
Boiling Point: Not applicable (decomposes before boiling)
Relative Density: 2.6 g/cm3 at 20 °C
pH (1% solution): 9–10
Vapor Pressure: Negligible at room temperature
Evaporation Rate: Not applicable
Flammability: Not flammable
Partition Coefficient: Not available
Auto-ignition Temperature: Not self-igniting
Chemical Stability: Stable under recommended storage conditions
Reactivity: Can react with acids to release toxic hydrogen selenide gas
Conditions to Avoid: Excessive heat, moisture, exposure to acids or strong oxidizers
Hazardous Decomposition: Selenium oxides, sodium oxides, possible release of hydrogen selenide
Polymerization: Does not undergo hazardous polymerization
Acute Toxicity: Oral LD50 (rat): 4 mg/kg
Chronic Exposure: Prolonged exposure can result in selenosis, characterized by gastrointestinal and neurological symptoms, hair and nail loss, skin eruptions
Routes of Exposure: Inhalation, ingestion, skin, eyes
Irritancy: Irritates eyes, respiratory tract, skin
Carcinogenicity: Not classified as carcinogenic by IARC or NTP
Mutagenicity: Evidence suggests potential for genetic defects
Reproductive Effects: Evidence of developmental toxicity in animals
Target Organs: Liver, kidneys, nervous system
Ecotoxicity: Highly toxic to aquatic organisms
Aquatic Toxicity: LC50 (fish, 96h): 0.7 mg/L
Persistence and Degradability: Compound is not readily biodegradable
Bioaccumulation: Potential for bioaccumulation in aquatic environments
Mobility in Soil: Dissolves and can migrate in water, contaminates soil and groundwater
Other Adverse Effects: Persistent environmental hazard, long-term harmful effects on aquatic life
Waste Disposal: Dispose of as hazardous chemical waste in accordance with local, regional, and national regulations
Contaminated Packaging: Decontaminate and recycle or dispose of as hazardous waste
Special Precautions: Prevent release to the environment; label waste clearly to indicate toxic selenium content; do not discharge into drains or natural water systems
UN Number: UN2630
Proper Shipping Name: Sodium selenite
Hazard Class: 6.1 (Toxic substances)
Packing Group: II
Labels Required: Toxic
Marine Pollutant: Yes
Special Precautions for Transport: Transport in original containers, keep tightly closed, do not transport with food or animal feed, follow all applicable transport regulations
TSCA: Listed in the US Toxic Substances Control Act inventory
OSHA Hazards: Highly toxic by ingestion, skin absorption, inhalation; hazardous to environment
SARA: Subject to Section 313 reporting (Toxic Release Inventory)
RCRA: Classified as hazardous waste under Code D010 (Selenium)
California Proposition 65: Not specifically listed
WHMIS Classification (Canada): D1A (very toxic), D2A (mutagenicity)
EINECS Number: 233-267-9
