Chemical Name: Monopyrrole
Synonyms: Pyrrole, Azole
CAS Number: 109-97-7
Use: Base for pharmaceutical and polymer synthesis, lab reagent
Appearance: Colorless to pale yellow liquid, mild amine odor
Supplier Information: Please check the label or your vendor file, as suppliers and contact data can change with location and time
Emergency Phone: Refer to local authority or supplier sheet for up-to-date numbers
Potential Health Effects: Eye, skin, and respiratory irritation; may cause severe discomfort in those with asthma or chemical sensitivities
GHS Classification: Flammable liquid, category 2; Acute toxicity, oral, category 4; Skin irritation, category 2
Hazard Statements: Highly flammable liquid and vapor. Harmful if swallowed. Causes skin irritation.
Precautionary Statements: Keep away from heat, spark, flame; avoid contact with skin and eyes; wash thoroughly after handling
Signal Word: Danger
Pictograms: Flame, exclamation mark
Chemical: Pyrrole
CAS No.: 109-97-7
Concentration: 100% for pure material
Impurities: Commercial samples might hold trace amounts of stabilizers or water, so refer to purchase specification for up-to-date lot information
Inhalation: Remove to fresh air, keep the person at rest, get prompt medical attention if breathing becomes difficult
Skin Contact: Take off contaminated clothing and rinse skin with plenty of water; persistent redness or irritation needs medical advice
Eye Contact: Rinse cautiously with water for several minutes, lifting eyelids occasionally; see a doctor if irritation persists
Ingestion: Rinse mouth to remove chemical, do not force vomiting, seek medical advice quickly
Symptoms: Coughing, headaches, dizziness, skin redness or burning feeling
Suitable Extinguishing Media: Foam, dry powder, carbon dioxide, sand
Unsuitable Media: Water streams can spread flames and vapors
Hazardous Combustion Products: Toxic fumes of nitrogen oxides and carbon oxides
Special Equipment: Firefighters wear self-contained breathing apparatus and protective suit
Other Fire Hazards: Vapors form explosive mixtures with air; containers can explode if heated
Personal Precautions: Evacuate area, ventilate space, eliminate ignition sources, use full protective gear
Environmental Precautions: Prevent entry into drains, soil, or waterways
Clean-Up Method: Absorb with inert material like vermiculite or sand, collect and seal in chemical waste drum
Spill Area Decontamination: Wash with plenty of water and detergent, dispose of residue as hazardous waste, no shortcuts on cleaning
Handling: Keep away from open flames and hot surfaces, use only in well-ventilated spaces, wear gloves and safety glasses
Hygiene Measures: Wash hands before meals or smoking, no eating in storage and handling zones
Storage: Store in tightly closed original container, keep cool (prefer below 25°C), secure away from oxidizers and acids
Incompatibilities: Strong acids, bases, oxidizing agents—risk of violent reaction
Other Notes: Container must stay upright and labeled, bulk storage needs grounding to protect from static sparks
Exposure Limits: No established TLV from ACGIH; OSHA—maintain workplace below 5 ppm where possible
Engineering Controls: Fume hood or mechanical exhaust works well; no reliance only on room ventilation
Personal Protection: Chemical-resistant gloves (nitrile or neoprene), splash goggles, lab coat or apron
Respiratory Protection: Wear approved respirator if vapor levels go up, especially outside the hood
Other Protective Measures: Eyewash station and safety shower nearby, clean up spills quickly, do not reuse clothing until washed
Physical State: Liquid
Color: Colorless to pale yellow
Odor: Amine-like, sometimes fishy
pH: Not applicable (non-aqueous)
Melting Point: −23°C
Boiling Point: 129°C
Flash Point: 31°C (closed cup)
Evaporation Rate: Not quick like acetone, but fast enough to matter
Flammability: Flammable liquid and vapor
Vapor Pressure: Around 13 mmHg at 25°C
Vapor Density: Greater than 1 (air = 1)
Density: 0.967 g/cm³
Solubility: Soluble in ethyl alcohol, benzene, diethyl ether; barely soluble in water
Partition Coefficient: Log Pow ≈ 0.65 (not likely to bioaccumulate)
Stability: Stable under recommended storage conditions, but not in sunlight or near oxidizers
Reactivity: Strong acids and bases kick off rapid, potentially dangerous reactions; may polymerize when heated or exposed to light
Hazardous Decomposition Products: Nitrogen oxides, carbon monoxide, carbon dioxide on burning
Polymerization: Unlikely below 40°C and away from bright light
Incompatible Materials: Store away from acid chlorides, strong oxidizers, and alkali metals—reaction can get out of hand
Routes of Exposure: Inhalation, skin contact, ingestion
Toxicity Data: Oral LD50 (rat): 500 mg/kg; inhalation LC50 not well defined but expect acute symptoms fast at high concentration
Health Effects: Acute exposure brings on irritation of eyes, throat, lungs; high doses can depress the nervous system, cause headaches and tremor
Chronic Effects: Prolonged or repeated exposure—risk of liver and kidney damage
Sensitization: No current evidence of allergic response, but avoid repeated skin exposure
Ecotoxicity: Toxic to aquatic life if released in quantity; fish and invertebrates show strong reaction at low concentrations
Persistence/Degradability: Slow breakdown in natural water, but does not stick around indefinitely—sunlight and microbes eventually destroy most residues
Bioaccumulation: Low, based on low partition coefficient; not likely to build up in food chains
Mobility in Soil: High; can move fast through sandy or open soils, risk to groundwater
Other Concerns: Avoid discharge into sewers or streams, work to keep spills on solid surfaces only
Waste Treatment: Small quantities—hold in hazardous waste container for collection by licensed service
Incineration: Best destroyed by chemical incinerators fitted with afterburners and scrubbers
Local Disposal Rules: Follow all national and local regulations, paperwork should be in order
Rinsing: Empty container must be triple-rinsed; do not throw in regular trash
Reuse/Recycle: Do not reuse containers for food or drink; potential contamination risk high
UN Number: UN2076
Proper Shipping Name: Pyrrole
Hazard Class: 3 (Flammable liquid)
Packing Group: II
Labels: Flammable liquid
Special Provisions: Keep away from ignition sources, maintain upright transport
Reportable Quantity: Regulations vary in different regions, check with transport coordinator for up-to-date numbers
OSHA Status: Hazardous chemical under criteria of OSHA Hazard Communication Standard
SARA Title III: Not listed as extremely hazardous; normal reporting for chemical inventory applies
TSCA: Listed in Toxic Substances Control Act Inventory; not restricted for research or industrial use
WHMIS (Canada): Classified as Class B2, flammable liquid; D2B, toxic
Other Labels: EC label: Harmful, highly flammable; NFPA—Health 2, Flammability 3, Reactivity 1
Country-Specific Rules: Always reach out to the local environmental health and safety team if rules seem unclear or if the application involves sensitive areas like food, pharma, or schools
