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Product Name: Zileuton
Chemical Name: 1-(1-Benzothiophen-2-ylethyl)-1-hydroxyurea
Synonyms: Zyflo, N-hydroxy-N-(1-benzothiophen-2-ylethyl)urea
CAS Number: 111406-87-2
Recommended Use: Leukotriene synthesis inhibitor, pharmaceutical product
Manufacturer: [Enter details of manufacturer/distributor]
Emergency Contact: [Insert local emergency telephone number]
Classification: Acute Toxicity (Oral) Category 4, Eye Irritation Category 2A, Skin Sensitization Category 1
Signal Word: WARNING
Hazard Statements: Harmful if swallowed. May cause allergic skin reaction. Causes serious eye irritation.
Precautionary Statements: Avoid breathing dust. Wash thoroughly after handling. Wear protective gloves, clothing, eye and face protection.
Symptoms of Exposure: Irritation to mouth and throat, redness, watering of eyes, itchiness or redness on skin, symptoms after prolonged exposure can include headache, nausea or drowsiness.
NFPA Ratings: Health: 2, Flammability: 1, Reactivity: 0
Zileuton: 95-99% (active ingredient)
Excipients: 1-5% (may include cellulose, starch, magnesium stearate)
Impurities: Not more than 0.1%
Inhalation: Move person to fresh air, encourage deep breathing, seek medical attention if symptoms persist such as chest discomfort or trouble breathing.
Skin Contact: Remove contaminated clothing, rinse skin with plenty of water for 15 minutes, use soap if available, consult medical help with evidence of rash or persistent irritation.
Eye Contact: Rinse cautiously with water for several minutes, remove contact lenses if easy to do so, continue rinsing, obtain medical care where irritation persists.
Ingestion: Rinse mouth, avoid inducing vomiting, give water, seek immediate physician attention if feeling unwell.
Suitable Extinguishing Media: Water spray, alcohol-resistant foam, dry chemical, carbon dioxide.
Hazards from Combustion: Emits toxic fumes including oxides of carbon, nitrogen, and sulfur during fire conditions.
Special Protective Equipment: Firefighters wear full protective clothing with self-contained breathing apparatus.
Precautions: Evacuate area, avoid inhalation of dust, smoke or decomposition products, prevent run-off from entering water systems.
Personal Precautions: Equip personal protective gear, avoid generating dust, ventilate area thoroughly, follow local regulations for chemical spills.
Spill Clean-Up Methods: Scoop up solid, avoid dry sweeping, place in a labeled waste container for disposal, wash area with plenty of water.
Environmental Precautions: Prevent further leakage or spillage, stop product from entering drains or waterways, report environmental release as required.
Handling: Use only in well-ventilated spaces, avoid breathing dust or contact with skin and eyes, keep containers tightly closed, do not eat, drink or smoke during use.
Storage: Keep in original container, store at controlled room temperature (20–25°C), protect from light and moisture, restrict access to authorized personnel, keep away from incompatible materials like strong oxidizers or acids.
Exposure Limits: No OSHA PEL or ACGIH TLV established for zileuton.
Engineering Controls: Use local exhaust or general room ventilation for dust control.
Personal Protective Equipment: Wear chemical-resistant gloves (nitrile recommended), safety glasses or goggles, lab coat, and appropriate respiratory protection in cases of insufficient ventilation or risk of dust formation.
Hygiene Measures: Wash hands thoroughly after use, remove contaminated clothing, avoid touching face or exposed skin during handling.
Appearance: White to off-white crystalline powder
Odor: Odorless
Odor Threshold: Not available
pH: Not available
Melting Point: 200–202°C
Boiling Point: Not applicable (decomposes before boiling)
Flash Point: >150°C (estimated)
Evaporation Rate: Not available
Flammability: Not considered highly flammable
Vapor Pressure: Negligible at room temperature
Solubility in Water: Poorly soluble
Partition Coefficient: (Log P): 2.5
Vapor Density: Not applicable
Relative Density (g/cm³): 1.24
Decomposition Temperature: >200°C
Chemical Stability: Stable under recommended storage conditions
Reactivity: Does not react violently under normal conditions
Conditions to Avoid: Excessive heat, sources of ignition, exposure to strong oxidizers or acid chlorides
Incompatible Materials: Strong acids, bases, oxidizers
Hazardous Decomposition Products: Emits toxic fumes of carbon monoxide, carbon dioxide, nitrogen oxides, sulfur oxides on decomposition or combustion.
Acute Toxicity: Harmful if swallowed, LD50 (oral, rat) approximately 300-2000 mg/kg
Skin Contact: May cause mild irritation or allergic reaction
Eye Contact: Causes moderate to severe irritation
Chronic Exposure: Not classified as carcinogenic by IARC, NTP, or OSHA, long-term studies show reversible liver enzyme changes in some animal studies
Mutagenicity: Not mutagenic in standard tests
Reproductive Toxicity: No clear evidence of reproductive or developmental toxicity in available studies
Sensitization: May cause allergic skin reaction in susceptible individuals.
Ecotoxicity: Toxic to aquatic organisms at high concentrations, risk of chronic effects in aquatic environments
Persistence and Degradability: Not readily biodegradable, may persist in the environment
Bioaccumulative Potential: Moderate potential, log Kow 2.5 indicates some accumulation possible
Mobility in Soil: Low mobility due to poor water solubility
Other Harmful Effects: Avoid uncontrolled release to water or soil; environmental monitoring recommended in case of large spill.
Waste Disposal: Collect residue and contaminated materials in sealed containers, dispose of using an authorized hazardous waste facility
Packaging Disposal: Rinse and dispose of packaging in accordance with local regulations for pharmaceutical waste
Precautions: Do not release to environment, do not mix with municipal waste streams
UN/NA Number: Not regulated as a hazardous material under current transport regulations
Proper Shipping Name: Zileuton
Transport Hazard Class: Not applicable
Packing Group: Not applicable
Marine Pollutant: Not classified as marine pollutant but avoid accidental release into watercourses
Special Precautions: Transport securely in well-sealed, labeled containers; follow country-specific regulations if transporting in bulk
Safety, Health and Environmental Regulations: Zileuton is classified as a prescription pharmaceutical product; not controlled under TSCA, SARA, or CERCLA; OSHA hazard communication regulations apply based on workplace chemical risk
International Inventory Status: Not subject to chemical inventory as an approved drug substance
Labeling: Must indicate hazard pictograms, signal words, and precautionary statements according to GHS criteria
Workplace Controls: Employers should ensure routine health and safety training for employees handling this material; medical surveillance and environmental controls as required by occupational health guidelines
Other State or Local Requirements: Subject to local environmental and safety regulations for pharmaceuticals; refer to official agencies for specific compliance.
