| Description | Methyl hydrazine, CH3NHNH2, is a colorless, hygroscopic liquid with an ammonia-like odor. It is soluble in water, with a specific gravity of 0.87, which is lighter than water. Methyl hydrazine is toxic by inhalation and ingestion, and is a suspected human carcinogen. The TLV ceiling is 0.2 ppm in air, and the IDLH is 50 ppm. The target organs are the central nervous system, respiratory system, liver, blood, eyes, and cardiovascular system. The four-digit UN identification number is 1244. The NFPA 704 designation is health 4, flammability 3, and reactivity 2. The primary uses are as a missile propellant and a solvent. |
| Chemical Properties | colourless liquid with an ammonia-like odour |
| Chemical Properties | Methyl hydrazine is a fuming, colorless liquidwith an ammonia-like odor. The odor threshold is1.31.7 ppm. |
| Physical properties | Fuming, clear, colorless liquid with an ammonia-like odor. Odor threshold concentrations rangedfrom 1 to 3 ppm (quoted, Keith and Walters, 1992). |
| Uses | Methylhydrazine is used in missile propellants and as asolvent and chemical intermediate. |
| Uses | Rocket fuel; solvent; chemicalintermediate |
| Uses | Missile propellant, intermediate, solvent. |
| Production Methods | Methylhydrazine ignites spontaneously on contact withstrong oxidizing agents. It is prepared commercially fromthe reaction of monochloroamine and monomethylamine. |
| Air & Water Reactions | Highly flammable. Often ignites spontaneously. Exposure to air on a large surface may result in spontaneous ignition [Def. Res. and Eng. 27. 1963]. Water soluble. Solutions are highly alkaline and generate heat when water is added. |
| Reactivity Profile | Methylhydrazine is a powerful reducing agent. Ignites upon contact with oxidizing agents i.e. dinitrogen tetraoxide, hydrogen peroxide [Hawley]. Water used to extinguish a fire may cause pollution and should be diked for later disposal. Gives basic solutions with water that generate heat when water is added. |
| Hazard | Flammable, dangerous fire risk, vapors mayexplode, may self-ignite in air and on contact withoxidizing agents. Toxic by ingestion and inhalation.Eye and upper respiratory tract irritant, lung cancerand liver damage. Possible carcinogen. |
| Health Hazard | Methyl hydrazine vapors are extremely toxic and the liquid is corrosive to skin. Methyl hydrazine is the strongest convulsant and the most toxic of methyl-substituted hydrazine derivatives. It is more toxic than hydrazine. At high doses, it is a strong central nervous system poison that can lead to convulsions and death. Skin rash may be aggravated by skin exposure. |
| Fire Hazard | Extremely flammable; ignites spontaneously under almost all normal temperature conditions. Water used to extinguish a fire may cause pollution and should be diked for later disposal. Water may be ineffective in extinguishing fires due to the chemical's low flash point. Because of the wide flammability limits, low flash point, and reignition hazard, dry chemicals, carbon dioxide, water spray, and foam may not be as effective as water dilution of fire area. The vapor is heavier than air; thus Methylhydrazine may accumulate sufficiently to flash back. Methylhydrazine fires produce irritating nitrogen oxides. Ignites spontaneously in air when in contact with porous materials (e.g., earth, asbestos, wood, or cloth). Also ignites spontaneously on contact with strong oxidizing agents (e.g., fluorine, chlorine trifluoride, fuming nitric acid, and nitrogen tetroxide). Heat or flame should be avoided because chemical is extremely flammable and explosive. |
| Safety Profile | Suspected carcinogenwith experimental carcinogenic,neoplastigenic, tumorigenic, and teratogenicdata. Poison by inhalation, ingestion, skincontact, intraperitoneal, subcutaneous, andintravenous routes. Experimentalreproductive effects. Human mutation datareported. Corrosive to skin, eyes and mucous membranes. May self-ignite in air.Very dangerous fire hazard when exposedto heat or flame. To fight fire, use alcoholfoam, CO2, dry chemical. Explosive in theform of vapor when exposed to heat orflame. A powerful reducing agent. It ishypergolic with many oxidants (e.g.,dinitrogen tetraoxide and hydrogenperoxide). When heated to decomposition itemits toxic fumes of NOx. |
| Potential Exposure | MMH has been used as the propellantin liquid propellant rockets; it is also used as a solvent andas an organic intermediate. |
| First aid | First Aid: If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek med-First Aid: If this chemical gets into the eyes, remove anycontact lenses at once and irrigate immediately for at least15 min, occasionally lifting upper and lower lids. Seek med-ical attention immediately. If this chemical contacts theskin, remove contaminated clothing and wash immediatelywith soap and water. Seek medical attention immediately. Ifthis chemical has been inhaled, remove from exposure,begin rescue breathing (using universal precautions, includ-ing resuscitation mask) if breathing has stopped and CPR ifheart action has stopped. Transfer promptly to a medicalfacility. When this chemical has been swallowed, get medi-cal attention. If victim is conscious, administer water ormilk. Do not induce vomiting. Medical observation isrecommended for 24- -48 h after breathing overexposure, aspulmonary edema may be delayed. As first aid for pulmo-nary edema, a doctor or authorized paramedic may consideradministering a corticosteroid spray.Note to physician:Treatfor methemoglobinemia.Spectrophotometry may be required for precise determina-tion of levels of methemoglobin in urine. |
| Carcinogenicity | The carcinogenicity of methylhydrazinehas been extensively investigated. In two studies,no compound-related increase in tumor incidence wasobserved in mice treated orally with methylhydrazine. In other studies, methylhydrazine producedlung tumors in mice and malignant histiocytoma of the liverand cecal tumors in hamsters when administered in drinkingwater at concentrations of 0.01%. Potential carcinogenicityfrom vapor exposure to methylhydrazine was alsoinvestigated in rats, dogs, hamsters, and mice. Exposures tomethylhydrazine at concentrations of 0.02 ppm (rats andmice only) and 0.2, 2, and 5 ppm (rats and hamsters only)were conducted for 6 h/day, 5 days/week, for a year, followedby observation for 1 year. |
| Source | Rocket fuel; solvent; intermediate; organic synthesis. |
| Environmental fate | Biological. It was suggested that the rapid disappearance of methylhydrazine in sterile andnonsterile soil (Arrendondo fine sand) under aerobic conditions was due to chemical oxidation.Although the oxidation product was not identified, it biodegraded to carbon dioxide in thenonsterile soil. The oxidation product did not degrade in the sterile soil (Ou and Street, 1988). |
| storage | Color Code—Red: Flammability Hazard: Store ina flammable liquid storage area or approved cabinet awayfrom ignition sources and corrosive and reactive materials.Prior to working with this chemical you should be trainedon its proper handling and storage. Before entering confinedspace where this chemical may be present, check to makesure that an explosive concentration does not exist. Methylhydrazine must be stored to avoid contact with oxides ofiron and copper; manganese, lead, and copper alloys;porous materials (such as earth, asbestos, wood, and cloth);oxidizers (such as perchlorates, hydrogen peroxide, chlorates, nitrates, permanganates); and fuming nitric acid sinceviolent reactions occur. Store in tightly closed containers ina cool, well-ventilated area away from heat and sparks.Sources of ignition, such as smoking and open flames, areprohibited where methyl hydrazine is handled, used, orstored. Metal containers involving the transfer of 5 gallonsor more of methyl hydrazine should be grounded andbonded. Drums must be equipped with self-closing valves,pressure vacuum bungs, and flame arresters. Use only nonsparking tools and equipment, especially when opening andclosing containers of methyl hydrazine. Wherever methylhydrazine is used, handled, manufactured, or stored, useexplosion-proof electrical equipment and fittings. A regulated, marked area should be established where this chemical is handled, used, or stored in compliance with OSHAStandard 1910.1045. |
| Shipping | UN1244 Methylhydrazine, Hazard class: 6.1;Labels: 6.1-Poison Inhalation Hazard, 3-Flammable liquid,8-Corrosive material, Inhalation Hazard Zone A |
| Purification Methods | Dry with BaO, then distil it in a vacuum. Store it under nitrogen. [Beilstein 4 IV 3322.] |
| Incompatibilities | May form explosive mixture with air.Methyl hydrazine is a highly reactive reducing agent and amedium strong base. May explode if heated. Violent reaction with strong oxidizers, such as fluorine, chlorine, combustibles, nitric acid; hydrogen peroxide. Incompatible withacids, alcohols, glycols, isocyanates, phenols, cresols;porous materials, such as earth, asbestos, wood and cloth.Oxides of iron or copper, manganese, lead, copper or theiralloys can lead to fire and explosions. Attacks cork, someplastics, coatings and rubber. |
| Toxics Screening Level | The initial risk screening level (IRSL) for methyl hydrazine is 0.0087 μg/m3 (annual). The initial threshold screening level (ITSL) is 0.03 μg/m3 (24-hour). |
| Waste Disposal | Consult with environmentalregulatory agencies for guidance on acceptable disposalpractices. Generators of waste containing this contaminant (≥100 kg/mo) must conform to EPA regulationsgoverning storage, transportation, treatment, and wastedisposal. There are 2 alternatives: Dilute with water,neutralize with sulfuric acid, then flush to sewer withlarge volumes of water or incinerate with added flammable solvent in furnace equipped with afterburner andalkaline scrubber. |
