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Name: P-Aminobenzenesulfonic Acid
Synonyms: Sulfanilic Acid
CAS Number: 121-57-3
Molecular Formula: C6H7NO3S
Appearance: White to off-white crystalline powder
Use: Often found in dyes, pharmaceuticals, analytical chemistry
Hazard Class: Not classified as hazardous according to GHS standards for most jurisdictions, though irritation risks exist
Target Organs: Eye, skin, respiratory tract
Symptoms: Eye and skin irritation, coughing if inhaled
Risk: Prolonged exposure creates dermatitis concerns or mild respiratory discomfort in very dusty situations
Main Component: p-Aminobenzenesulfonic Acid (pure content usually above 99 percent)
Impurities: Minimal, sometimes unreacted precursors or byproducts if technical grade
Form: Crystalline solid
Eye Contact: Rinse thoroughly with clean water for at least 15 minutes, blink occasionally, seek care if irritation persists
Skin Contact: Wash off with soap and water, take off contaminated clothing
Inhalation: Move to fresh air, get medical attention if symptoms remain
Ingestion: Rinse mouth, drink water if able, see medical help if feeling unwell
Sensitivity: Not especially flammable, may produce toxic fumes like nitrogen oxides and sulfur oxides in large fires
Extinguishing Media: Water spray, CO2, dry chemical, foam work well, avoid direct water jet on spilled solid
Protective Gear: Standard firefighting gear and self-contained breathing apparatus
Fire Hazards: Powder can disperse into air in big spills and may irritate airways or eyes of responders
Personal Precautions: Wear gloves, goggles, dust mask or respirator if large spill, make sure ventilation removes dust
Containment: Sweep up, avoid generating dust clouds, collect in solids container
Cleaning: Wipe down with damp cloth or wash floors to clear up traces, dispose of with regular chemical waste in sealed bag
Environmental Caution: Don’t flush down public drains—risk to aquatic life exists in concentrated form
Handling: Use in well-ventilated areas, avoid breathing dust or getting powder in eyes
Hygiene: Wash hands after use, never eat or drink near work bench
Storage Conditions: Cool, dry, ventilated space away from direct sunlight and sources of moisture
Separation: Keep away from strong oxidizers, bases, and acids to avoid unwanted reactions
Workplace Limits: No established occupational exposure limits in most countries, but common-sense precautions still count
Protection: Nitrile/rubber gloves, tight-fitting goggles, dust mask in case of airborne powder
Engineering Controls: Install exhaust ventilation or fume hoods for large-scale handling, avoid accumulation of dust on surfaces
Appearance: White to off-white crystal
Odor: Odorless
Melting Point: About 288°C (decomposes)
Solubility: Soluble in water, more so when warm, low solubility in organic solvents
pH (1% Solution): Neutral to slightly acidic
Density: Around 1.48 g/cm³
Boiling Point: Not applicable (decomposes before boiling)
Stability: Stable under normal storage and handling
Reactive Conditions: Caution if mixed with strong oxidizers, acids, or bases
Decomposition: Emits sulfur and nitrogen oxides when heated to high temperatures
Polymerization: Not expected under normal conditions
Route of Entry: Inhalation, ingestion, skin, or eye contact
Acute Effects: Low toxicity in animal studies, irritation on contact
Sensitization: Not a known allergen
Chronic Effects: Not well documented, but repeated contact with skin or eyes should still be avoided
Carcinogenicity: Not listed as a known or probable carcinogen by international authorities
Aquatic Toxicity: Harmful to aquatic organisms at higher concentrations
Degradability: Breaks down in wastewater treatment over time, but not quickly
Mobility: Bound by soil—does not spread far in groundwater
Bioaccumulation: No significant bioaccumulation expected in the food chain
Waste: Collect all spills and contaminated material in sealed containers, send to appropriate disposal site
Avoid: Draining to sewers or natural water bodies
Local Regulations: Follow specific local laws for hazardous waste disposal—even if the risk is limited, safe practice keeps workplaces responsible to people and nature
UN Number: No specific assignment for common package sizes
Hazard Class for Shipping: Generally shipped as non-dangerous goods on land
Packing: Keep in sealed, labeled bags or drums, limit shifting to avoid spills
Transport Precautions: Don’t ship with strong oxidizers or reactive chemicals, and always seal up well to limit dust escape
Global Inventory: Catalogued in chemical inventories like TSCA (US), REACH (EU), DSL (Canada)
Labeling: Usually handled as a “non-hazardous” industrial chemical, although some countries require irritant labels
Usage Restrictions: No global bans but watch for emerging safety updates if new hazards come to light through research or changing regulations
