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Chemical Name: Thallium Hydroxide
Common Name: Thallium(I) Hydroxide
Chemical Formula: TlOH
Physical State: White, crystalline solid
Odor: Odorless
Uses: Laboratory research, chemical synthesis
CAS Number: 1311-21-1
Acute Toxicity: Highly toxic by inhalation, ingestion, and skin absorption
Chronic Effects: Long-term exposure can damage nervous system, liver, and kidneys
Routes of Exposure: Skin, eyes, inhalation, ingestion
Symptoms: Nausea, muscle pain, hair loss, tremors, abdominal pain
Carcinogenicity: Not classified by IARC as carcinogen but recognized for severe, irreversible health hazards
Pictograms: Skull and crossbones, health hazard symbol, exclamation mark
Chemical Composition: Thallium Hydroxide, TlOH
Purity: Typically over 98% by weight
Hazardous Ingredients: Contains only thallium hydroxide without additives; thallium compounds are acutely hazardous to health
Inhalation: Remove victim to fresh air; seek medical attention immediately
Skin Contact: Remove contaminated clothing, rinse skin with plenty of water for at least 15 minutes
Eye Contact: Rinse cautiously under running water for at least 15 minutes, remove contact lenses if present
Ingestion: Seek immediate medical attention; do not induce vomiting unless instructed by a medical professional
Emergency Notes: Immediate care is critical due to thallium’s extreme toxicity; early hospital intervention helps prevent irreversible damage
Suitable Extinguishing Media: Use water spray, alcohol-resistant foam, dry chemical, or carbon dioxide
Hazards from Combustion: Never let the firewater drain into sewage systems, as thallium compounds contaminate groundwater
Special Protective Equipment: Full protective gear and self-contained breathing apparatus for fire responders
Specific Dangers: Upon heating, toxic fumes of thallium and its oxides may form
Advice: Keep run-off out of the environment; contain firewater if possible
Personal Protection: Full chemical splash suit, face shield, and proper respiratory protection required
Cleanup Methods: Collect material using chemical-resistant equipment; avoid dust formation
Environmental Precautions: Prevent release to water, soil, and drains; thallium is severely toxic to aquatic and terrestrial life
Decontamination: Clean spill site with attention to enclosure and ventilation; dispose of all cleanup material in accordance with hazardous waste protocols
Handling: Work in certified chemical fume hood; minimize dust and direct contact; restrict access to trained professionals
Storage: Store in tightly closed containers made from materials not corroded by alkaline chemicals
Environmental Control: Keep away from drains and water sources; use secondary containment
Incompatibilities: Strong acids, oxidizers, and materials reactive with caustics should not be stored near Thallium Hydroxide
Occupational Exposure Limits: OSHA PEL: 0.1 mg/m³ (as thallium, skin)
Engineering Controls: Highly-efficient fume hoods, local exhaust ventilation, and isolation procedures used in all transfers
Personal Protective Equipment: Impervious gloves, chemical-resistant clothing, eye protection, and respiratory protection such as P3 or N100 filters
Hygiene Strategies: Wash hands and face thoroughly before eating, drinking, or smoking; no food or drink allowed in storage or handling areas
Appearance: White crystalline solid
Solubility: Soluble in water, giving alkaline solution
Melting Point: Above 100 °C (decomposes before melting)
Boiling Point: Decomposes on heating
Odor Threshold: Odorless
Density: Approximately 4.5 g/cm3
Chemical Stability: Stable in closed containers at room temperature
Hazardous Decomposition Products: Thallium oxide, caustic fumes upon heating
Conditions to Avoid: Contact with strong acids, exposure to heat and moisture
Incompatible Materials: Acids, oxidizers, and chlorinated solvents increase risk of hazardous reactions
Polymerization: Not known to undergo hazardous polymerization
Absorption: Rapidly absorbed through skin, GI tract, and lungs
Acute Toxicity Data: Oral LD50 in rats: approximately 32 mg/kg
Symptoms of Exposure: Abdominal pain, vomiting, hair loss, tremors, convulsions, severe neurological impairment
Chronic Toxicity: Effects may include peripheral neuropathy, vision disturbances, organ failure
Mutagenicity and Teratogenicity: Data suggest possible developmental toxicity and mutagenic effects
Sensitization: No widely-reported skin sensitization but rapid poisoning dominates the clinical picture
Environmental Fate: Thallium ions persist in the environment, posing severe risks to aquatic life and bioaccumulating in food chains
Aquatic Toxicity: Lethal to aquatic organisms at very low concentrations
Terrestrial Impact: Toxic to plants and wildlife
Bioaccumulation Potential: High
Mobility in Soil: Highly mobile in moist earth, contaminates groundwater readily
Waste Disposal Methods: Hazardous waste incineration in facilities authorized for heavy metal destruction
Packaging: Dispose of contaminated containers as hazardous waste
Avoidance: Never discharge to water systems or municipal landfills
Legal Framework: Subject to strict hazardous waste regulations under national and international law
UN Number: 1707 (Thallium compound, n.o.s.)
Shipping Name: Thallium compound, inorganic, solid, n.o.s.
Hazard Class: 6.1 (Toxic substances)
Packing Group: I (highest danger)
Special Transport Notes: Secure tightly; labeling required showing acute health risks; all handlers must be certified for toxic shipments; accidental release triggers emergency HAZMAT protocols on land, sea, and air routes
Classification: Controlled as acutely hazardous under several chemical safety regulations
Worker Protection Laws: Strict training and medical monitoring for all who are exposed professionally
Environmental Regulations: Inclusion on priority pollutant lists subject to reporting under national and international conventions
Import/Export Restrictions: Legal trade tightly monitored, permits required for transport and use
Reporting Thresholds: Low thresholds for mandatory reporting of spills, exposures, and environmental releases, reflecting the compound’s potent toxicity
Local Regulations: Jurisdictions may impose still tighter rules, especially near water bodies or population centers
