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Product name: 4-Hydroxybenzoic Acid
Chemical formula: C7H6O3
Synonyms: p-Hydroxybenzoic acid, para-Hydroxybenzoic acid
CAS number: 99-96-7
Recommended use: Raw material for preservatives, intermediate in organic synthesis
Supplier: Information available from distributor safety department
Emergency contact: Local poison control center, fire department hazardous materials response unit
Classification: Eye irritation - Category 2; Skin irritation - Category 2
Hazard statements: Causes skin irritation, serious eye irritation possible
Precautionary statements: Wear gloves, eye protection, protective clothing; avoid breathing dust or vapors
Signal word: Warning
UN Number: Not regulated
Pictograms: Exclamation mark for skin and eye irritation
Potential health effects: Skin redness, eye discomfort, respiratory irritation if particulate dust is inhaled
Symptoms from overexposure: Burning or tearing sensation in eyes, itching and redness on skin
Chemical identity: 4-Hydroxybenzoic Acid
Concentration: >99% pure in most laboratory-grade samples
Impurities: Trace levels of related benzoic acids, manufacturing byproducts
Hazardous components: No highly toxic components present
Molecular weight: 138.12 g/mol
Eye contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy. Continue rinsing, seek medical attention if irritation persists.
Skin contact: Wash with plenty of soap and water, remove contaminated clothing, consult a physician if skin redness develops.
Inhalation: Move citizen to fresh air, keep comfortable for breathing, get immediate medical advice for persistent symptoms.
Ingestion: Rinse mouth thoroughly, drink water if conscious, do not induce vomiting, alert toxicology center or physician.
Special notes: Symptomatic treatment, observation may be required for significant exposure.
Suitable extinguishing media: Water spray, foam, dry chemical, carbon dioxide
Unsuitable extinguishing media: Strong water jets may spread contaminated material
Hazardous combustion products: Carbon oxides, organic vapors
Special protective equipment: Firefighters should use full protective clothing and self-contained breathing apparatus
Fire hazards: Combustible solid in fine dust form, not highly flammable but powder can present dust explosion risk
Advice for firefighters: Move containers away from fire zone if safe, keep upwind, prevent runoff entering drains
Personal precautions: Evacuate unprotected personnel, ventilate area, avoid dust formation, wear suitable PPE
Environmental precautions: Prevent release to waterways, drains, or soil
Containment: Sweep or scoop up material with minimal dust formation, store in suitable labeled container
Cleanup methods: Wash spilled area with water, collect washings for proper disposal, decontaminate surfaces and equipment
Disposal: Comply with local regulatory guidelines for chemical waste
Notification: Report significant spills to environmental authorities in accordance with regulations
Safe handling: Minimize dust generation, use local exhaust if handling large amounts, avoid breathing dust, wash hands after use
Storage conditions: Store in tightly closed container, keep in a cool, dry, well-ventilated place, avoid exposure to direct sunlight or heat
Incompatibilities: Strong oxidizers, reducing agents, strong bases
Storage class: Keep away from food and drink, do not store with incompatible materials mentioned above
Specific considerations: Keep out of reach of children, ensure proper labeling of storage containers
Occupational exposure limits: No established OSHA or ACGIH limits; general dust exposure limits may apply (10 mg/m³ for total dust, 3 mg/m³ for respirable fraction)
Engineering controls: Use local exhaust ventilation, process enclosures, dust collection systems
Personal protection: Protective safety glasses or goggles, appropriate gloves (nitrile or equivalent), lab coat or protective clothing
Respiratory protection: NIOSH-approved dust mask or respirator if exposure to airborne particulates possible
Hygiene measures: Wash thoroughly after handling, keep work area clean, do not eat or drink in work area
Appearance: White to off-white crystalline powder
Odor: Faint; slightly phenolic
Odor threshold: Not determined
pH value: 4.2 (1% aqueous solution)
Melting point: 213-217°C (415-423°F)
Boiling point: Decomposes before boiling
Solubility: Sparingly soluble in water (6.9 g/L at 20°C), more soluble in alcohol, ether
Vapor pressure: Negligible at room temperature
Density: 1.47 g/cm³
Partition coefficient (log Kow): 1.58
Other properties: Stable under normal conditions, not volatile at ambient temperatures
Stability: Stable under recommended storage and handling conditions
Reactivity: Does not undergo hazardous polymerization
Incompatible materials: Strong oxidizers, strong bases; may react vigorously
Conditions to avoid: Excessive heat, open flame, direct sunlight
Hazardous decomposition products: Carbon dioxide, carbon monoxide, various organic compounds
Special warnings: Avoid dust formation, which increases risk of fire or respiratory exposure
Routes of exposure: Eye contact, skin contact, inhalation, ingestion
Acute toxicity: Oral LD50 (rat): 2200 mg/kg
Skin irritation: May irritate with direct contact; not a skin sensitizer on normal exposure
Eye irritation: Causes moderate to severe irritation with redness, watering
Inhalation toxicity: Dust may cause transient respiratory tract irritation
Mutagenicity/Carcinogenicity: No evidence from reliable animal studies to suggest mutagenic or carcinogenic potential
Chronic effects: Repeated or prolonged skin contact can cause dermatitis in sensitive individuals
Aquatic toxicity: Harmful to aquatic life at higher concentrations; LC50 (fish, 96 h): 100 mg/L
Persistence and degradability: Biodegradable in aquatic and soil environments
Bioaccumulation potential: Low, based on partition coefficient
Mobility in soil: Moderately mobile due to low water solubility
Environmental warnings: Avoid release to natural waters, minimize accidental discharge, notify authorities in case of larger spill
Waste treatment: Dispose of using hazardous waste incineration or at an approved chemical landfill
Contaminated packaging: Clean thoroughly before recycling or disposal; treat as chemical waste if contaminated
Local regulations: Follow all local, regional, and national guidance for chemical disposal
Reuse/recycling: Do not reuse empty containers for food or drinking water
Bulk disposal: Seek professional chemical waste contractor advice for large volumes
UN Number: Not classified as hazardous for transport
Proper shipping name: 4-Hydroxybenzoic Acid
Transport hazard class: Not regulated
Packing group: Not assigned
Labeling: No specific label required for ground or air shipments under typical use; ensure clear chemical identification on packaging
Special transport notes: Prevent package breakage, keep away from oxidizers and incompatible materials during transport
OSHA: Not listed as a hazardous chemical under US OSHA standards
SARA Title III: Not classified under Section 313
TSCA: Listed in US Toxic Substances Control Act inventory
REACH (EU): Product is registered and compliant with European standards
DSL (Canada): Listed on Canadian Domestic Substances List
Other national regulations: Comply with all country-specific regulations regarding handling and use
Labelling requirements: Product name, hazard pictograms, signal word, and manufacturer emergency contact to be on all containers
