Colorless crystalline solid with a faint odor, sublimes readily.
As an antioxidant in the rubber, chemical, photographic, dye, fat, & oil industries, in cosmetics & some pharmaceuticals.
Registry Numbers and Inventories.
EC Index Number
R 21/22 36/38
S 22 26 37
Agricultural Chemical and Pesticide; Tumorigen; Mutagen; Reproductive Effector
Swiss Giftliste 1
Japan ENCS (MITI)
Melting point, °C
103 - 105
Boiling point, °C
Vapor pressure, mmHg
0.018 (25 C)
Vapor density (air=1)
1316 ppm (0.13%) at 75 C (calculated)
1.0548 g/cm3 (20 C)
Solubility in water
2.17 cp (121 C)
1.515 (20 C)
Partition coefficient, pKow
Heat of fusion
Heat of vaporization
Heat of combustion
Hazards and Protection.
Keep container closed when not in use. Material can ignite if dry. Do not allow material to completely dry. Keep from contact with oxidizing materials. Corrosives area. Store in a cool, dry area away from incompatible substances.
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use only in a well ventilated area. Minimize dust generation and accumulation. Do not breathe dust, vapor, mist, or gas. Do not get in eyes, on skin, or on clothing. Keep container tightly closed. Discard contaminated shoes.
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.
Vacuum or sweep up material and place into a suitable disposal container. Clean up spills immediately, using the appropriate protective equipment. Avoid generating dusty conditions. Remove all sources of ignition. Provide ventilation.
Stable under normal shipping and handling conditions. Substance undergoes color change upon exposure to light and air.
Strong oxidizing agents, strong reducing agents, strong acids, strong bases.
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.
Upper exp. limit, %
Lower exp. limit, %
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. 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. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. Non-combustible, substance itself does not burn but may decompose upon heating to produce irritating, corrosive and/or toxic fumes. Extinguishing media: 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.
This material is combustible.
POISONOUS GASES MAY BE PRODUCED WHEN HEATED. May form toxic fumes at high temperatures.
Fire may produce irritating, corrosive and/or toxic gases.
5 ppm TLV
G-A3, I-2B, CP65
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. Effects may be delayed.
Harmful if swallowed. May cause severe and permanent damage to the digestive tract. Causes gastrointestinal irritation with nausea, vomiting and diarrhea. May cause perforation of the digestive tract. May cause methemoglobinemia, cyanosis, convulsions, and death. May cause central nervous system depression. May cause systemic effects. May cause a prolonged rise in blood pressure which may lead to degenerative changes in the
May cause severe irritation of the respiratory tract with sore throat, coughing, shortness of breath and delayed lung edema. Causes chemical burns to the respiratory tract. May cause effects similar to those described for ingestion. Aspiration may lead to pulmonary edema. May cause systemic effects.
Harmful if absorbed through the skin. Causes skin burns. Prolonged and/or repeated contact may cause irritation and/or dermatitis. May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material. If absorbed, causes symptoms similar to those of ingestion. May cause skin rash (in milder cases), and cold and clammy skin with cyanosis or pale color.
Causes eye burns. May cause chemical conjunctivitis and corneal 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 flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse. Destroy contaminated shoes.
Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Extensive irrigation is required (at least 30 minutes).
I; II; III
USCG CHRIS Code
2907 29 00