© 2026 Nanjing Finechem Holdings Co., Ltd,
All Right Reserved
Chemical Name: 4-Nitrocatechol
Synonyms: 4-Nitro-1,2-dihydroxybenzene
Chemical Formula: C6H5NO4
Appearance: Often appears as pale to bright yellow crystalline powder; may shift toward deeper yellow in bulk. Chemical structure includes both nitro and catechol functional groups, which influence its reactive profile. CAS number and legal identifiers usually mark substances like this, yet most lab folks simply recognize it by its strong coloration and bitter odor reminiscent of other nitrophenols.
Acute Toxicity: Harmful if swallowed, inhaled, or upon skin contact. Laboratory evidence suggests significant irritation to eyes and mucous membranes.
Risk Phrases: Prolonged or repeated exposure can have cumulative effects. Nitroaromatic compounds often come with an increased risk of organ toxicity, mainly affecting blood and liver.
Symbol: Warning sign for harmful substances.
Potential Exposure Routes: Fine powder creates dust that can be inhaled or settle quickly on exposed skin, clothing, and surfaces, making hygiene a priority.
Purity: Frequently greater than 97% in lab or reagent bottles, though one should test for break-down products, especially if stock has aged.
Main Component: 4-Nitrocatechol.
Typical Contaminants: Minute traces of dihydroxybenzene isomers and nitro derivatives linger from production. Impurities may change the safety profile slightly but handling protocols don’t relax, even for “pure” samples.
Skin Contact: Wash with a lot of water. Remove contaminated clothing quickly; the compound’s bright color can linger on skin, hinting at incomplete removal.
Eye Contact: Rinse eyes cautiously with water for many minutes. Get medical attention swiftly.
Inhalation: Move to fresh air right away. Provide oxygen if breathing difficulties start. Medical evaluation is strongly recommended after significant inhalation.
Ingestion: Rinse mouth with water, avoid inducing vomiting unless instructed by medical personnel. Supportive medical care is essential since nitro compounds can be absorbed into the bloodstream and cause methemoglobinemia.
Flammability: May burn under intense heat, generating toxic gases like NOx and CO; the nitro group boosts risk in a fire scenario.
Suitable Extinguishing Media: Use foam, dry powder, or carbon dioxide. Water spray may spread powder or create run-off contamination.
Protective Equipment: Firefighters need full protective gear plus self-contained breathing protection to dodge vapor, smoke, or residues. Excessive inhalation of breakdown fumes can injure even seasoned responders.
Spill Response: Isolate area, keep unnecessary personnel away. Wear gloves, goggles, and a fitted mask. Carefully scoop up debris and dust with wet tools if workable, guard against generating airborne particles.
Environmental Precautions: Avoid entry into soil, drains, or water systems—nitrophenols linger in the environment, build up, and upset aquatic life.
Disposal Materials: Use non-combustible absorbents like vermiculite or sand to control spread, gather residues in tight-sealing containers for later disposal by qualified waste handlers.
Handling Practices: Only open containers in well-ventilated labs. Practice double-gloving and train everyone in the hazards. Label workspaces, store all tools and waste together to control cross-contamination.
Storage Conditions: Keep in tightly sealed bottles, sheltered from light, in secure, cool cabinets intended for hazardous chemicals. Keep away from incompatible substances such as oxidizers and bases; don’t trust old labels—audit storage often.
Special Risks: Nitroaromatic powders slowly degrade under moisture or heat, sometimes forming more hazardous byproducts. Periodic checks for leaks, spills, or discoloration can prevent more severe incidents.
Ventilation: Use fume hoods. General room fans fail to control airborne dust.
Personal Protective Equipment: Gloves resistant to chemicals, solid goggles, and lab coats are not optional. Respiratory protection is necessary while handling large quantities or if powders become airborne. Avoid open skin; lab shoes matter as spills reach the floor.
Work Practices: Change gloves immediately after contamination, and avoid consuming food or drink anywhere near the workspace. Wash all exposed skin thoroughly after work—nitro aromatics have a habit of sticking around, literally.
Physical State: Crystalline solid
Color: Pale to deep yellow
Odor: Mild but distinctive phenolic smell
Melting Point: Varies slightly by purity, usually around 140–145°C
Solubility: Soluble in water, alcohol, and most organic solvents
Other Properties: Moderately acidic; nitro group enhances reactivity toward bases and reductants. This molecule can stain surfaces and skin yellowish-brown; clean-up requires more than a casual rinse.
Chemical Stability: Stable under dry, sealed conditions away from sunlight or strong heat sources.
Hazardous Decomposition Products: May form nitrogen oxides and other noxious gases under intense heat or fire.
Incompatibilities: Bases, strong oxidizers, reducing agents—these trigger unwanted reactions and are best stored far apart.
Polymerization: No known polymerization hazard under normal storage, but don’t overlook the risk from impurities that may boost reactivity over time.
Routes of Exposure: Inhalation, skin and eye contact, ingestion.
Symptoms of Exposure: Irritation to eyes and skin, headache, dizziness, possible cyanosis due to methemoglobinemia. Chronic exposure may affect blood or organ function.
Relevant Studies: Animal studies indicate nitrocatechols affect red cell function, amplify oxidative stress, and may raise cancer risk over long-term exposure. Little room for error: protection is non-negotiable for anyone around this substance.
Long-Term Impacts: Nitroaromatic compounds have a reputation for cumulative effects, so even minor slips in containment or personal hygiene can lead to real health issues over time.
Aquatic Toxicity: Highly toxic to aquatic life; low breakdown rates in rivers and soil.
Persistence and Degradability: Chemical structure resists rapid microbial breakdown. Environmental half-life extends into months without active remediation.
Bioaccumulation: Tends to build up in aquatic organisms. Potential for food-chain transfer.
Other Considerations: Discharge into water bodies is not only a bad idea but opens up real regulatory headaches and long-term harm to ecosystems.
Safe Disposal Routes: Handle as hazardous waste; use licensed chemical waste processing. Don’t flush down the sink or mix with regular garbage.
Waste Handling: Place all solids and contaminated materials in tightly sealed, labeled containers. Keep records of disposal as required by waste regulations.
Incineration: Best handled by facilities equipped for nitroaromatic substances, as regular municipal incinerators won’t scrub resulting NOx well enough.
Transportation Risk: UN numbers may assign this to hazardous chemical categories, especially for air or sea transport. Packages require tough outer containers, clear hazard labels, and tight seals around the inner containers.
Handling in Transit: Drivers and handlers use gloves and masks, steer clear of rough handling that could break packages or release dust.
Spill Response In Transit: Transport crews are trained to isolate any releases, avoid spark sources, and contact authorities for containment and cleanup right away.
National Rules: Many countries regulate nitroaromatics as hazardous substances, with restrictions on purchase, use, and disposal.
Worker Safety: OSHA, EPA, and their global equivalents require training, labeling, and exposure controls for workers.
Environmental Rules: Discharge and disposal require permits and tracking—no exceptions for lab or industrial settings.
Gaps: Regulations evolve as new data comes out on long-term impacts; companies and labs must regularly review updates to avoid lapses.
