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Name: Pyrrole
Chemical Formula: C4H5N
Common Names: Azole, 1H-Pyrrole
Appearance: Colorless to pale yellow liquid, aromatic odor
CAS Number: 109-97-7
Usage: Widely found in organic synthesis, pharmaceuticals, dyes, and research laboratories
Main Hazards: Flammable liquid and vapor, causes irritation to eyes, skin, and respiratory tract, harmful if swallowed or inhaled
Acute Health Effects: Eye redness, skin irritation, coughing or throat discomfort, drowsiness
Fire Risk: Vapors mix easily with air forming explosive mixtures, ignition can occur at low temperatures
Chronic Exposure: May cause long-term damage to organs, repeated skin contact increases sensitivity
Active Ingredient: Pyrrole, purity typically above 98% for laboratory use
Other Components: May contain trace levels of water or polymerization inhibitors
Impurities: Residual solvents or degradation products possible, often depend on storage
Inhalation: Remove to fresh air, keep at rest, seek medical attention if symptoms linger
Skin Contact: Rinse affected area well with water and mild soap, remove contaminated clothing
Eye Contact: Flush eyes gently with lukewarm water for 10-15 minutes, do not rub eyes, medical evaluation recommended
Ingestion: Rinse mouth, do not induce vomiting, prompt medical help advised, monitor for confusion or drowsiness
Extinguishing Media: Dry chemical powder, carbon dioxide, or foam recommended; water spray may control fire but risk of spreading exists
Special Hazards: Vapors travel distance to ignition sources; combustion releases toxic nitrogen oxides
Firefighter Protection: Full protective gear and self-contained breathing apparatus necessary
Additional Concerns: Prevent runoff from contaminating drains or waterways
Personal Precautions: Leave area if vapor present, ventilate before entry, wear protective gloves, goggles, and clothing
Spill Response: Use non-sparking tools, absorb with inert material such as sand or vermiculite, collect in tightly sealed containers
Environmental Safety: Keep away from drains, groundwater, or soil to avoid contamination
Decontamination: Wash affected surfaces with detergent, air out area before reuse
Handling: Work in a fume hood or with proper ventilation, keep away from heat, open flames, and static discharge
Safe Storage: Store in tightly closed containers, in a cool, well-ventilated location, keep away from oxidizers
Incompatibilities: Strong acids, bases, oxidizing reagents, direct sunlight increases risk of polymerization or degradation
Routine Precautions: Avoid rough handling or dropping containers as leaks quickly vaporize
Engineering Controls: Work only with local exhaust ventilation, mechanical general ventilation helps reduce vapor buildup
Personal Protective Equipment: Nitrile or neoprene gloves, safety goggles, laboratory coat, and, for high vapor concentrations, properly rated respirators
Hygiene Measures: Wash hands before breaks and after work, avoid eating or drinking in work areas, remove contaminated clothing immediately
Physical State: Liquid
Color: Colorless to pale yellow
Odor: Distinct sweet, tarry smell
Boiling Point: Around 129°C
Melting Point: -23°C
Vapor Pressure: Moderate at room temperature
Solubility: Insoluble in water, mixes with common organic solvents such as ethanol, ether, acetone
Flash Point: Near 31°C (closed cup)
Density: Around 0.97 g/cm3
Viscosity: Thin, spreads easily
Chemical Stability: Sensitive to air and light; can slowly polymerize and darken with prolonged exposure
Reactivity: Vigorous reactions possible with strong acids, bases, oxidizers
Hazardous Decomposition: Produces toxic fumes including nitrogen oxides and carbon monoxide in a fire
Polymerization Risk: Accelerated by heat, acids, and light; proper storage key for long shelf life
Acute Effects: Vapor inhalation causes headache, dizziness, nausea; prolonged contact causes skin inflammation or eye irritation
Ingestion Effects: Can cause mouth and throat discomfort, stomach upset, and nervous system depression
Long-Term Exposure: Repeated absorption may disrupt liver or kidney function, heightened sensitivity on skin
Animal Studies: Laboratory data show moderate toxicity with delayed symptoms, some effects reversible if exposure stops early
Impact on Water: Toxic to aquatic life, low biodegradability increases long-term hazard
Air Emissions: Vapors contribute to air pollution, especially in enclosed spaces
Soil Absorption: Limited mobility; binds to soil, risk of contamination accumulates over time
Bioaccumulation: Tends not to build up in the food chain but harms smaller organisms
Recommended Practice: Gather waste in sealed, clearly labeled containers, use licensed chemical disposal facilities
Drain Disposal: Should never pour into sewage, waterways, or trash bins; follow local and federal hazardous waste rules
Decontamination: Clean up tools and containers with strong detergents, avoid transferring residues
Environmental Responsibility: Dispose with attention to minimizing long-term pollution, consult regulatory agencies for updated methods
Transport Risk: Classified as hazardous for road, rail, sea, and air; flammable liquid regulations apply
Packaging: Use approved containers that prevent leakage, avoid glass or unstable plastics
Handling: Trained personnel required during shipment, emergency response information should accompany cargo
Labeling: Clearly mark with correct chemical name and hazard stickers to ensure safety and legal compliance
Global Harmonization: Pyrrole ranks as a flammable irritant, subject to chemical inventory requirements in North America, Europe, and Asia
PPE Standards: Occupational exposure limits vary by country, with strict controls on airborne concentrations in most settings
Worker Safety: Local worker protection laws often demand clear training, incident documentation, and regular health monitoring
Environmental Laws: Disposal and spill reporting legally binding, as aqueous and vapor emissions face fines and corrective actions
