Common Name: 1-Phenyl-3-methyl-5-pyrazolone
Chemical Structure: Pyrazolone ring substituted with phenyl at position 1, methyl at position 3
Synonyms: PMP, Phenylmethylpyrazolone
Appearance: Typically seen as a yellow to pale yellow crystalline solid
Typical Use: Organic synthesis, analytical chemistry, reagent for carbohydrate derivatization
Main Risk: Skin and eye irritation from contact
Other Risks: Potential respiratory tract discomfort if dust is inhaled; risk climbs with airborne particles
Fire Hazard: Combustible under certain conditions
Chronic Issues: Prolonged exposure may dry or crack skin; no clear evidence of long-term systemic toxicity in typical laboratory practices
Chemical Identity: 1-Phenyl-3-methyl-5-pyrazolone
Chemical Formula: C10H10N2O
Purity: Generally sold with a purity of over 98% for laboratory use
Eye Contact: Rinse eyes carefully under running water, keep eyelid open for several minutes
Skin Contact: Wash skin thoroughly with soap and water, remove contaminated clothing
Inhalation: Move person to fresh air, provide breathing support if necessary
Ingestion: Rinse mouth, seek medical support if symptoms develop
Continued Monitoring: Monitor for allergic or respiratory reactions, consult physician for any ongoing irritation
Appropriate Extinguishing Media: Water spray, dry chemical powder, carbon dioxide, foam
Hazardous Combustion Products: Carbon oxides, nitrogen oxides as possible byproducts
Protective Gear for Firefighters: Full protective clothing, self-contained breathing apparatus
Flammability: Though not highly flammable, dust accumulations pose a risk if exposed to ignition sources
Personal Protection: Wear nitrile gloves, safety goggles, dust mask during cleanup
Spill Handling: Avoid dust creation; sweep up and collect in labeled containers
Ventilation: Keep area well-ventilated after spills to disperse residual dust particles
Environmental Precautions: Prevent large quantities from washing into water drains, soil, or open water systems
Safe Handling: Use with local ventilation, minimize dust formation
Storage: Keep container tightly closed, store in cool, well-ventilated place away from ignition sources
Container Integrity: Ensure containers are resealed after every use, check for leaks or cracks regularly
Segregation: Keep away from incompatible substances like strong oxidizers
Engineering Controls: Work under a fume hood, use dust extraction systems as needed
Personal Protection: Nitrile gloves, lab coats, safety goggles or face shields, dust mask or respirator if airborne concentration climbs
Hygiene Measures: Wash hands thoroughly after handling, prevent ingestion or skin exposure by using double-gloving techniques if contact seems likely
Exposure Limit Values: No established occupational exposure limits, but reasonable engineering controls keep risks low
Form: Solid
Color: Pale yellow to yellow
Odor: Practically odorless
Melting Point: Typically between 128–131°C
Solubility: Slightly soluble in water, freely in organic solvents like chloroform and ethanol
Vapor Pressure, Boiling Point: Very low vapor pressure at room temperature; decomposition at higher temperatures without boiling in atmospheric conditions
Chemical Stability: Stable under recommended conditions of storage and use
Reactivity: Low reactivity under ambient conditions; strong oxidizing agents may stimulate hazardous reactions
Conditions to Avoid: Excessive heat, sparks, open flames, and sources of ignition
Decomposition: Heating above decomposition temperature releases carbon monoxide, carbon dioxide, nitrogen oxides
Acute Toxicity: Low acute toxicity based on available laboratory animal studies; may cause irritation on contact or inhalation
Chronic Exposure: No strong data for systemic toxicity with normal laboratory exposure; no association with carcinogenic effects, reproductive or developmental harms in available literature
Symptoms of Exposure: Redness, irritation, dryness, possible mild cough or throat irritation in presence of dust
Aquatic Impact: Limited information available, though small quantities do not appear to cause significant short-term effects on aquatic organisms
Persistence and Degradability: Organic structure suggests some tendency to degrade over time under environmental conditions, though persistent residues may remain in soil
Bioaccumulation: No evidence of significant bioaccumulation, but best practice always involves limiting release into the environment
Wastewater: Avoid large or repeated releases to drains or natural waterways
Waste Disposal: Place solid or contaminated materials in labeled containers for hazardous chemical waste
Incineration: Safe disposal by high-temperature incineration in accordance with regional regulations
Container Rinsing: Triple rinse emptied container before discarding or recycling, as trace residues present environmental concerns
Avoid: Disposing with regular waste or pouring large quantities down the drain; work with certified chemical waste handlers
Transportation: Carry in tightly closed, clearly marked containers to reduce risk of leaks or spills
Regulations: Not classified as dangerous for the purposes of most regional and international transport rules but must be handled according to chemical safety standards
Precautions: Keep away from food, feed, or medical supplies during shipment
Legal Controls: Subject to chemical safety regulations in most workplaces and laboratories
Hazard Classification: Typically not assigned hazard classes for broad transport, but requires basic chemical handling controls
Reporting Requirements: Amounts stored above certain thresholds may require notification to environmental health authorities under local laws
User Responsibility: Familiarity with local, state, national chemical safety and disposal laws remains key to compliance and safety
