Colorless crystals or liquid, turns yellow to dark red on exposure to air and light, faint aromatic odor.
Manufacture dyes, antipyrine, nitron (a stabilizer for explosives), reagent for sugars, aldehydes, ketones.
Registry Numbers and Inventories.
EC Index Number
Carcinogenic Category 2; Mutagenic Category 3; Toxic; Irritant; Sensitising; Dangerous for the Environment
R 45 23/24/25 36/38 43 48/23/24/25 50
S 53 45 61
Tumorigen; Mutagen; Reproductive Effector
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
0.03 (25 C)
Vapor density (air=1)
52.6 ppm (0.0053%) at 20 C (calculated)
Odor Threshold Odor threshold 1 to 10 ppm
Solubility in water
4.58 cp (50 C)
45.6 g/s2 (20 C)
1.602 (17.7 C)
Partition coefficient, pKow
Heat of fusion
Heat of vaporization
Heat of combustion
Hazards and Protection.
Keep away from heat, sparks, and flame. Keep away from sources of ignition. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Do not expose to air. Store protected from light. Store under an inert atmosphere.
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Do not get in eyes, on skin, or on clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Avoid contact with heat, sparks and flame. Do not ingest or inhale. Store protected from light. Handle under an inert atmosphere. Store protected from air. Use only in a chemical fume hood. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use.
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container. Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. Place under an inert atmosphere. Do not get water inside containers.
Stable under normal temperatures and pressures. Turns reddish-brown on exposure to light.
Oxidizing agents, lead dioxide, perchloryl fluoride, 2-phenylamino-3-phenyloxazirane, air, isopropylamine, isobutylamine, lead (IV) oxide.
Nitrogen oxides, carbon monoxide, irritating and toxic fumes and gases, carbon dioxide, nitrogen.
Upper exp. limit, %
Lower exp. limit, %
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Water runoff can cause environmental damage. Dike and collect water used to fight fire. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Use water spray to keep fire-exposed containers cool. Combustible Liquid. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Extinguishing media: Use water spray to cool fire-exposed containers. Use agent most appropriate to extinguish fire. Do NOT get water inside containers. For small fires, use dry chemical, carbon dioxide, or water spray. For large fires, use dry chemical, carbon dioxide, alcohol-resistant foam, or water spray. Cool containers with flooding quantities of water until well after fire is out.
Moderate when exposed to heat or flame.
When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards.
Irritating vapors and toxic gases, such as nitrogen oxides and carbon monoxide, may be formed when involved in fire.
OSHA PEL: TWA 5 ppm (22 mg/m3) skin NIOSH REL: Ca C 0.14 ppm (0.6 mg/m3) 2-hr skin See Appendix A NIOSH IDLH: Potential occupational carcinogen 15 ppm
Possible cancer hazard based on tests with laboratory animals. Prolonged or repeated skin contact may cause dermatitis. Prolonged or repeated eye contact may cause conjunctivitis. Chronic inhalation and ingestion may cause effects similar to those of acute inhalation and ingestion. May cause methemoglobinemia, which is characterized by chocolate-brown colored blood, headache, weakness, dizziness, breath shortness, cyanosis, rapid heart rate, unconsciousness and possible death. May cause fetal effects. Laboratory experiments have resulted in mutagenic effects.
Harmful if swallowed. May cause kidney, liver and spleen damage. May cause bone marrow damage. May cause systemic effects by ingestion: blood hemolysis with or without anemia, methemoglobinemia-carboxyhemoglobinemia, and pulmonary changes. Causes digestive tract irritation with possible burns.
Harmful if inhaled. May cause effects similar to those described for ingestion. Causes severe respiratory tract irritation. Inhalation may produce weakness, fatigue, dizziness, and vertigo. Acute exposure to low concentrations of hydrazines may cause and produce bronchial mucous destruction, pulmonary edema, cyanosis and possible death.
Causes severe skin irritation. May be fatal if absorbed through the skin. May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material. May cause eczematous dermatitis with swelling and vesiculation.
Causes severe eye irritation. May cause retinal damage.
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
Get medical aid immediately. Remove from exposure to fresh air immediately. If breathing is difficult, give oxygen. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.
USCG CHRIS Code
2928 00 90
Std. Transport #