Methylhydrazin

log Kow= -1.05

-1.05

Odor characteristic of short chain, organic amines

Ammonia-like odor

0.874 at 77 °F (EPA, 1998) - Less dense than water; will float

0.874 at 25 °C

Relative density (water = 1): 0.87

0.874 at 77 °F

0.874 @25 °C

(77 °F): 0.87

Clear liquid

Fuming, colorless liquid.

Insoluble (<1 mg/ml at 75 °F) (NTP, 1992)

>10% in ethyl ether

>10% in ethanol

>10% in water

SOL IN PETROLEUM ETHER

For more Solubility (Complete) data for METHYLHYDRAZINE (6 total), please visit the HSDB record page.

158 °F (EPA, 1998)

-8 °C, 17 °F (closed cup)

-8.3 °C c.c.

70 °F

17 °F

190 °F at 760 mmHg (EPA, 1998)

87.5 °C

87.5 °C

190 °F

87.5 °C @760 [mm Hg]

190 °F

-62.3 °F (EPA, 1998)

-52.4 °C

-52.4 °C

-62.3 °F

-52.36 °C

-62 °F

1.6 (EPA, 1998) - Heavier than air; will sink (Relative to Air)

1.6 (AIR= 1)

Relative vapor density (air = 1): 1.6

1.6

Danger

H350: May cause cancer [Danger Carcinogenicity]

P203, P280, P318, P405, and P501 (click each P-code to see the statement)

Danger

Chemical: Hydrazine, methyl-

Status: Active Update: 16-02-2018 https://echa.europa.eu/registration-dossier/-/registered-dossier/13414；Status: Cease Manufacture Update: 15-11-2012 https://echa.europa.eu/registration-dossier/-/registered-dossier/1502；Status: Active Update: 11-01-2017 https://echa.europa.eu/registration-dossier/-/registered-dossier/18686；Status: Active Update: 22-03-2011 https://echa.europa.eu/registration-dossier/-/registered-dossier/6669

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

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 it 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. (EPA, 1998)

· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.；CAUTION: Methanol (UN1230) will burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.)；· Vapors may form explosive mixtures with air.；· Vapors may travel to source of ignition and flash back.；· Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.).；· Vapor explosion and poison hazard indoors, outdoors or in sewers.；· Those substances designated with a (P) may polymerize explosively when heated or involved in a fire.；· Runoff to sewer may create fire or explosion hazard.；· Containers may explode when heated.；· Many liquids will float on water.

Highly flammable. Many reactions may cause fire or explosion. Gives off irritating or toxic fumes (or gases) in a fire. Vapour/air mixtures are explosive. Risk of fire and explosion on contact with oxidizing agents or metal oxides.

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. (EPA, 1998)

· TOXIC; may be fatal if inhaled, ingested or absorbed through skin.；· Inhalation or contact with some of these materials will irritate or burn skin and eyes.；· Methyl chloroacetate (UN2295) is an eye irritant/lachrymator (causes flow of tears).；· Fire will produce irritating, corrosive and/or toxic gases.；· Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas.；· Runoff from fire control or dilution water may cause environmental contamination.

Methylhydrazine is used as a high-energy fuel in military applications. Acute (short-term) inhalation exposure to high levels of methylhydrazine may cause lacrimation, eye redness, nasal and respiratory irritation, headache, malaise, vomiting, diarrhea, ataxia, anoxia, cyanosis, tremors, and convulsions in humans. Acute exposure to methylhydrazine in humans has also been observed to affect the blood, kidneys, and liver. Methylhydrazine is highly corrosive and irritating to the skin, eyes, and mucous membranes of the respiratory system in humans and animals. Chronic (long-term) inhalation exposure to methylhydrazine has been observed to impair function of the kidneys and liver, affect the blood and spleen, and cause convulsions in animals. EPA has not classified methylhydrazine for carcinogenicity.

Liquid causes second or third degree burns after short contact; [CHRIS] Toxic effects resemble those of hydrazine with mucous membrane irritation, methemoglobinemia, hemolytic anemia, and central nervous system injury; [ACGIH] May produce pulmonary edema after high inhalation exposure; [ICSC] In high-dose reproductive studies of animals, hydrazine derivatives (hydrazine, MMH, and UDMH) cause testicular damage and fetal loss, and hydrazine causes birth defects. [Frazier, p. 341-2] Hydrazines antagonize GABA in the CNS causing excitation and seizures. Pyridoxine, vitamin B6, is a specific antidote for this effect. [AHLS, p. 426]

1244 131

1244 131

Wear positive pressure breathing apparatus and special (full) protective clothing. No skin surface should be exposed. Isolate area for 1/2-mile in all directions if a tank car or truck is involved in a fire.；For small fires, use dry chemical, carbon dioxide, water spray, and foam. For large fires, use water spray, fog, or foam. Keep unnecessary people away and isolate the hazardous area. Stay upwind and keep out of low-lying areas.；Fire exposed containers should be kept cool with water. Use water spray to disperse vapors and protect men attempting to stop a leak which has not ignited. Move container from fire area if it can be done without risk. (EPA, 1998)

Use water in large amounts, powder, alcohol-resistant foam, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water. Combat fire from a sheltered position.

Fresh air, rest. Artificial respiration may be needed. Refer for medical attention.

First rinse with plenty of water for at least 15 minutes, then remove contaminated clothes and rinse again. Refer for medical attention .

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Do NOT induce vomiting. Give one or two glasses of water to drink. Refer for medical attention .

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.；· Keep unauthorized personnel away.；· Stay upwind, uphill and/or upstream.；· Ventilate closed spaces before entering, but only if properly trained and equipped.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.；· All equipment used when handling the product must be grounded.；· Do not touch or walk through spilled material.；· Stop leak if you can do it without risk.；· Prevent entry into waterways, sewers, basements or confined areas.；· A vapor-suppressing foam may be used to reduce vapors.；Small Spill；· Absorb with earth, sand or other non-combustible material and transfer to containers for later disposal.；· Use clean, non-sparking tools to collect absorbed material.；Large Spill；· Dike far ahead of liquid spill for later disposal.；· Water spray may reduce vapor, but may not prevent ignition in closed spaces.

Warning: Symptoms may be delayed from hours to days. Caution is advised.；Signs and Symptoms of Acute Methyl Hydrazine Exposure: Symptoms of acute exposure to methyl hydrazine may include facial numbness, facial swelling, and increased salivation. Headache, twitching, seizure, convulsions, and coma may also occur. Gastrointestinal signs and symptoms include anorexia, nausea, and vomiting. Pulmonary edema and hypotension (low blood pressure) are common. Methyl hydrazine is toxic to the liver, ruptures red blood cells, and may cause kidney damage. Contact with the skin, eyes, or mucous membranes may result in severe irritation and permanent damage.；Emergency Life-Support Procedures: Acute exposure to methyl hydrazine may require decontamination and life support for the victims. Emergency personnel should wear protective clothing appropriate to the type and degree of contamination. Air-purifying or supplied-air respiratory equipment should also be worn, as necessary. Rescue vehicles should carry supplies such as plastic sheeting and disposable plastic bags to assist in preventing spread of contamination.；Inhalation Exposure:；1. Move victims to fresh air. Emergency personnel should avoid self-exposure to methyl hydrazine.；2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.；3. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.；4. RUSH to a health care facility.；Dermal/Eye Exposure:；1. Remove victims from exposure. Emergency personnel should avoid self- exposure to methyl hydrazine.；2. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.；3. Remove contaminated clothing as soon as possible.；4. If eye exposure has occurred, eyes must be flushed with lukewarm water for at least 15 minutes.；5. Wash exposed skin areas THOROUGHLY with soap and water.；6. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.；7. RUSH to a health care facility.；Ingestion Exposure:；1. Evaluate vital signs including pulse and respiratory rate, and note any trauma. If no pulse is detected, provide CPR. If not breathing, provide artificial respiration. If breathing is labored, administer oxygen or other respiratory support.；2. Obtain authorization and/or further instructions from the local hospital for administration of an antidote or performance of other invasive procedures.；3. Give the victims water or milk: children up to 1 year old, 125 mL (4 oz or 1/2 cup); children 1 to 12 years old, 200 mL (6 oz or 3/4 cup); adults, 250 mL (8 oz or 1 cup). Water or milk should be given only if victims are conscious and alert.

General First Aid:；· Call 911 or emergency medical service.；· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.；· Move victim to fresh air if it can be done safely.；· Administer oxygen if breathing is difficult.；· If victim is not breathing:；-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.；-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).；-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.；· Remove and isolate contaminated clothing and shoes.；· For minor skin contact, avoid spreading material on unaffected skin.；· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.；· For severe burns, immediate medical attention is required.；· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.；· Keep victim calm and warm.；· Keep victim under observation.；· For further assistance, contact your local Poison Control Center.；· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.；Specific First Aid:；· Wash skin with soap and water.

(General first aid procedures)；Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.；Skin: Water flush immediately - If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly.；Breathing: Respiratory support；Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Vapors are heavier than air and may travel to a source of ignition and flash back.

Prolonged exposure of the containers of the material to fire or heat may result in the spontaneous decomposition of the material & violent rupture of the container.

· Wear positive pressure self-contained breathing apparatus (SCBA).；· Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE.；· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

TIH (Toxic Inhalation Hazard) - Term used to describe gases and volatile liquids that are toxic when inhaled. Some are TIH materials themselves, e.g., chlorine, and some release TIH gases when spilled in water, e.g., chlorosilanes. [ERG 2016].

Use flooding quantities of water. Use water spray to keep fire-exposed containers cool. Fight fire from protected location or maximum possible distance. Approach fire from upwind to avoid hazardous vapors and toxic decomposition products.

If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Solid streams of water may be ineffective. Use "alcohol" foam, dry chemical or carbon dioxide.

Wear butyl rubber gloves, self-contained breathing apparatus, eye protection and impervious clothing. Body shield should be available. Eliminate all sources of ignition and flammables. On skin or clothing. Wash skin immediately. Remove contaminated clothing at once. Spills: Cover spill with a 1:1:1 mixture by weight of sodium carbonate or calcium carbonate, clay cat litter (bentonite) and sand. Scoop the solid into a container, transport to the fume hood and slowly add to water allowing 20 ml water for each 1 g of methylhydrazine. Filter off the clay and sand. For each 1 g of methylhydrazine, place 41 ml (about 25% excess) of commercial laundry bleach (containing about 5.25% sodium hypochlorite) into a 3-necked round-bottom flask equipped with a stirrer, thermometer and dropping funnel. Add the aqueous methylhydrazine dropwise to the stirred hypochlorite solution, monitoring the rate of addition by rise in temperature. The temperature is maintained at 45-50 °C and addition takes about 1 hour. Stirring is continued for 2 hours until the temperature gradually falls to room temperature.

Excerpt from ERG Guide 131 [Flammable Liquids - Toxic]:；ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors.；SMALL SPILL: Absorb with earth, sand or other non-combustible material and transfer to containers for later disposal. Use clean, non-sparking tools to collect absorbed material.；LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number P068, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Methyl hydrazine is a good candidate for liquid injection incineration with a temperature range of 650 to 1600 °C and a residence time of 0.1 to 2 seconds. Also a good candidate for rotary kiln incineration with a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases; for solids hours. Also a good candidate fluidized bed incineration with a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases; longer for solids.

Small Quantities. Wear butyl rubber gloves, laboratory coat and eye prolection. Work in the fume hood. Prepare a dilute (5%) aqueous solution of methylhydrazine by adding slowly to the appropriate volume of water. For each 1 g of methylhydrazine, place 41 ml (about 25% excess) of household laundry bleach (5.25% sodium hypochlorite) into a 3-necked round-bottom flask equipped with a stirrer, thermometer and dropping funnel. Add the aqueous methylhydrazine dropwise to the stirred hypochlorite solution, monitoring the rate of addition by rise in temperature. The temperature is maintained at 45-50 °C and addition takes about 1 hour. Stirring is continued for 2 hours until the temperature gradually falls to room temperature.

Incomplete reaction of hypochlorite with the methylated hydrazine fuels monomethylhydrazine and unsymmetrical dimethylhydrazine leads to a wide variety of byproducts, including N-nitrosoamines, which are believed to be highly carcinogenic.

Administration of methylhydrazine to mice decreases survival of animals after x-irradiation, inhibited growth of Ehrlich ascites tumor, and increased number of cells with chromosome aberrations.

Methylhydrazine was tested for synergism in promoting in vitro oncogenic transformation of Swiss mouse 3T3 cells by herpes simplex type 2 virus (hsv-2). Methylhydrazine enhanced level of oncogenic transformation approx 2-fold.

Several inhibitors of the FAD-containing monooxygenase (FAD-MO) system from rat liver microsomes (imipramine, chloropromazine, mercaptoethylamine, dithiothreitol, naphthylthiourea, phenylthiocarbamide) and one inhibitor of the liver microsomal cytochrome P450-mediated biotransformations, were tested as possible inhibitors of monomethylhydrazine (MMH) biotransformation to carbon dioxide and to reactive metabolites that bind covalently to nucleic acids and proteins. Results confirm previous suggestions that both FAD-containing monooxygenase system and P450 are involved in monomethylhydrazine metabolism to carbon dioxide and suggest a similar participation of both systems for production of reactive metabolites interacting with macromolecules.

Single sc injections of substituted hydrazines were given alone and jointly with pyridoxine hydrochloride to Swiss mice. The convulsive, toxic and lethal effects of methylhydrazine were successfully prevented by administration of pyridoxine hydrochloride before and/or after injection.

For more Interactions (Complete) data for METHYLHYDRAZINE (7 total), please visit the HSDB record page.

LC50 Hyalella azteca (amphipod) 1.2 mg/L/48 hr /Conditions of bioassay not specified/

LC50 Lebistes reticulatus (Guppy) 5.3; 6.7 mg/L/24 hr; 3.7; 4.0 mg/L/48 hr; 2.7; 3.7 mg/L/72 hr; 2.6; 3.3 mg/L/96 hr; static

LC50 Asellus sp. (Aquatic sowbug) 820 ug/L/48 hr (95% confidence interval: 300-2300 ug/L); static

LC50 Ictalurus punctatus (Channel catfish) 3540 ug/L/96 hr (95% confidence interval: 2510-4970 ug/L); static

For more Ecotoxicity Values (Complete) data for METHYLHYDRAZINE (6 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 18(SRC), determined from a structure estimation method(2), indicates that methylhydrazine is expected to have very high mobility in soil(SRC). Methylhydrazine is a weak base with a pKa of 7.87(3). This pKa value indicates that this compound will partially exist as a cation in moist soils, and cations may adsorb to soil more than neutral compounds(SRC). Volatilization of the protonated species from moist soils will not occur since cations do not volatilize. Volatilization of the free base may occur, based on an estimated Henry's Law constant of 3X10-6 atm-cu m/mole(SRC), calculated from its vapor pressure, 50 mm Hg(4), and water solubility, 1X10+6 mg/L(5). Volatilization from dry soils may occur based on the vapor pressure of this compound(4). Approximately 0%, 5%, 20%, and 8% degradation of methylhydrazine was observed in a 1 hour soil column study using a cleaned sand (100% sand), sandy soil (99.1% sand, 0.4% clay, pH 6.1), organic soil (96.1% sand, 1% clay, 1% carbon, pH 6.4) and clay (69.3% sand, 27.95% clay, pH 3.7)(6).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 18(SRC), determined from a structure estimation method(2), indicates that methylhydrazine is not expected to adsorb to suspended solids and sediment(SRC). Methylhydrazine is a weak base with a pKa of 7.87(3). This pKa value indicates that this compound will partially exist as a cation in water, and cations may adsorb to suspended solids and sediment more than neutral compounds(SRC). Volatilization of the protonated species will not occur since cations do not volatilize. Volatilization of the free base may occur(4), based on an estimated Henry's Law constant of 3X10-6 atm-cu m/mole(SRC), calculated from its vapor pressure, 50 mm Hg(5), and water solubility, 1X10+6 mg/L(6). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(3) is estimated as 5 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(4) is estimated as 62 days(SRC). According to a classification scheme(7), an estimated BCF of 3(SRC), from a log Kow of -1.05(8) and a regression-derived equation(9), suggests the potential for bioconcentration in aquatic organisms is low(SRC). The estimated half-lives of methylhydrazine present at 9.5 mM in pond and sea water are 18.0 and 24.1 days, respectively, and at 19.0 mM are 13.1 days in both pond and sea water(10).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methylhydrazine, which has a measured vapor pressure of 50 mm Hg at 25 °C(2), will exist solely as a vapor in the ambient atmosphere. Vapor-phase methylhydrazine is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be about 6 hours(SRC) calculated from its rate constant of 6.50X10-11 cu cm/molecule-sec at 25 °C(3). Assuming an ozone concentration of 7X10+11 molecules/cu cm, a maximum half-life of about 3.3 min for the reaction of methylhydrazine with ozone was estimated from a minimum rate constant of 5X10-15 cu cm/molecule sec(4,SRC). The half-life for the reaction between ozone and methylhydrazine was estimated to be <1 min during ozone pollution episodes and <12 min in the 'natural' troposphere(5). Reaction of methylhydrazine with ozone is expected to be the predominant fate of methylhydrazine in the atmosphere(SRC).

Neurotoxin - Other CNS neurotoxin；Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.；Methemoglobinemia - The presence of increased methemoglobin in the blood; the compound is classified as secondary toxic effect；Reproductive Toxin - A chemical that is toxic to the reproductive system, including defects in the progeny and injury to male or female reproductive function. Reproductive toxicity includes developmental effects. See Guidelines for Reproductive Toxicity Risk Assessment.；Dermatotoxin - Skin burns.；Toxic Pneumonitis - Inflammation of the lungs induced by inhalation of metal fumes or toxic gases and vapors.；ACGIH Carcinogen - Confirmed Animal.

The substance can be absorbed into the body by inhalation of its vapour, through the skin and by ingestion.

inhalation, skin absorption, ingestion, skin and/or eye contact

Burning sensation. Cough. Nausea. Vomiting. Blue lips, fingernails and skin. Dizziness. Headache. Shortness of breath. Laboured breathing. Convulsions. Symptoms may be delayed.

MAY BE ABSORBED! Redness. Skin burns. Pain. Further see Inhalation.

Redness. Pain. Severe deep burns.

Abdominal cramps. Burning sensation. Shock or collapse. Further see Inhalation.

irritation eyes, skin, respiratory system; vomiting, diarrhea, tremor, ataxia; anoxia, cyanosis; convulsions; [potential occupational carcinogen]

Placement medical examinations shall include at least: comprehensive medical and work histories; comprehensive physical examination; specific clinical tests including complete and differential blood count; liver function tests including serum glutamic-pyruvic transaminase (SGPT), urinalysis including specific gravity, glucose, protein, and microscopic examination, and a 14 x 17 inch posteroanterior chest roentenogram; a judgement of the worker's ability to use positive pressure respirators; and urobilinogen and serum bilirubin tests shall be considered by the responsible physician. Periodic examinations shall be made available at least annually to those working with hydrazines. /Hydrazines/

Using a structure estimation method based on molecular connectivity indices(1), the Koc for methylhydrazine can be estimated to be 18(SRC). According to a classification scheme(2), this estimated Koc value suggests that methylhydrazine is expected to have very high mobility in soil. The pKa of methylhydrazine is 7.87(3). This pKa value indicates that this compound will partially exist as a cation in moist soils and cations generally adsorb more strongly to organic carbon and clay than the corresponding free base(4).

Of the initial amount of methylhydrazine in sand, Vandenburg Air Force Base (VAFB) soil (99.1% sand, 0.4% clay, pH 6.1), organic soil (96.1% sand, 1% clay, 1% carbon, pH 6.4) and clay (69.3% sand, 27.95% clay, pH 3.7), 3%, 46%, 26%, and 64% was adsorbed, respectively(1). Passage of 2 liters of distilled, deionized water through columns containing sand, VAFB soil, organic soil and clay (10% clay plus 90% pure sand) treated with 10 ml of a 0.1 v/v solution of methylhydrazine resulted in 86.9%, 5.5%, 6.5%, 6.3% recovery of methylhydrazine, respectively(1).

Chemical: Hydrazine, methyl-

Status: Active Update: 16-02-2018 https://echa.europa.eu/registration-dossier/-/registered-dossier/13414；Status: Cease Manufacture Update: 15-11-2012 https://echa.europa.eu/registration-dossier/-/registered-dossier/1502；Status: Active Update: 11-01-2017 https://echa.europa.eu/registration-dossier/-/registered-dossier/18686；Status: Active Update: 22-03-2011 https://echa.europa.eu/registration-dossier/-/registered-dossier/6669

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

P068; As stipulated in 40 CFR 261.33, when methyl hydrazine, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to federal and/or state hazardous waste regulations. Also defined as a hazardous waste is any container or inner liner used to hold this waste or any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5(e)).

Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Methyl hydrazine is included on this list.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 10 lb or 4.54 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Methyl hydrazine is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 500 lbs.

Methyl hydrazine

1

15000

Toxic chemical that can be released at a facility.

The enzyme systems in rat liver and lung responsible for the oxidative metabolism of hydrazine derivatives were studied to determine whether these enzymes, cytochrome P450 and monoamine oxidase, were responsible for metabolically activating hydrazines to carcinogenic/toxic metabolites. Cytochrome P450 preferentially oxidized the nitrogen to nitrogen bond of 1,2-disubstituted hydrazines and hydrazides, while monoamine oxidase oxidized the nitrogen to nitrogen bond of all the classes of hydrazine derivatives that were tested. Oxidation of the nitrogen to nitrogen bond led to the formation of stable azo intermediates in the case of 1,2-disubstituted hydrazines and to unstable monoazo (diazene) metabolites in the case of monosubstituted hydrazines and hydrazides. /Substituted hydrazines/

Radio respirometric data from rats continuously infused with specifically 14C-labeled glucose and other substrates indicates that monomethyl hydrazine (MMH) inhibits glycolysis. The effect is evidently at the phosphofructokinase step. ...

Methylhydrazine shows first-order kinetics in blood following iv or oral dosing. The course of elimination in the digestive tract was nonlinear. The half-life in the digestive tract was only 1.74 min, and the absorption rate was 50-60%. Methylhydrazine in the digestive tract could be totally eliminated. The time for eliminating half of the oral dose was <5 min. Methylhydrazine was widely distributed in the murine body, and the half-life of the distribution phase was only 1.08-1.5 min, whereas that of the elimination phase was 37-52 min.

The /half life/ for elimination /in rabbits following inhalation exposure/ was 2.4 and 4.4 hr.

The n-oxidation of methylhydrazine catalyzed by purified mouse liver microsomal mixed function amine oxidase is shown. At pH 7.7 and 25 °C, methylhydrazine has nearly the same maximal n-oxidation rate as dimethylaniline. Although methane can be detected as a product of n-oxidation of methylhydrazine, it may represent the chemical decomposition product of a n-oxidized intermediate.

Flavoprotein n-oxygenase... catalyzes formation of... n-oxides of methylhydrazine /and/ 1,1-dimethylhydrazine... .

Isolated hepatocytes and liver microsomes incubated with monomethylhydrazine, 1,1-dimethylhydrazine and 1,2-dimethylhydrazine produced free radical intermediates which were detected by ESR spectroscopy by using 4-pyridyl-1-oxide-t-butyl nitrone as spin trapping agent. The spectral features of the spin adducts derived from all three hydrazine derivatives corresponded to the values reported for the methyl free radical adduct of 4-pyridyl-1-oxide-t-butyl nitrone. In the microsomal preparations, inhibitors of the mixed function oxidase system and the destruction of cytochrome P450 by pretreating the rats with cobalt chloride all decreased the free radical formation. Methimazole, an inhibitor of FAD-containing monoxygenase system, similarly decreased the activation of 1,1-dimethylhydrazine, but not that of monomethylhydrazine and 1,2-dimethylhydrazine. The addition to liver microsomes of physiological concentrations of glutathione (GSH) lowered by approx 80% the intensities of the ESR signals. Consistently, incubation of isolated hepatocytes with methylhydrazine decreased the intracellular GSH content, suggesting that GSH can effectively scavenge the methyl free radicals. The results obtained suggest that methyl free radicals could be the alkylating species responsible for the toxic and/or carcinogenic effect of methylhydrazines.

Methylhydrazine can be metabolized to carbon dioxide by rat liver slices. Reactive metabolites that were capable of binding covalently to nucleic acids were detected. Biotransformation of methylhydrazine might not be a detoxification process but may produce metabolites that are themselves active. No liver DNA guanine could be methylated in hamsters given the highest feasible doses of methylhydrazine. This does not appear to be an important intermediate in the methylation of DNA guanine seen in hydrazine-treated animals. Monoalkylhydrazines, including methylhydrazine, were converted to the corresponding hydrocarbons in the presence of liver microsomes, oxygen, and energy-producing co-factors. Mixed-function aminooxidases in the liver can oxidize alkylhydrazines in the presence of oxygen and NADPH. The formation of methane from methylhydrazine may be due to the decomposition of an N-oxidation intermediate. ...Methylhydrazine is oxidized by neutrophils (from rat peritoneal exudates) leading to the formation of alkyl radicals. Azide could inhibit this step.

Methylhydrazine is absorbed from the lung, GI tract, injection sites, and skin.

(14)C labeled methylhydrazine was administered to mice, dogs, and monkeys. All species excreted 25-40% of the dose in urine within 24 hr. In mice ... approx the same amount was excreted in respired air. Both carbon dioxide and radioactive methane were found.

The respiratory and urinary excretion of ip administered monomethylhydrazine (MMH) by rats was studied by means of radiotracer technique. Rats given 0.12 mM/kg respired approx 45% of the labeled carbon during the following 24 hr. Of the respired radioactivity, 20-25% was (14)C labeled carbon dioxide and the remainder was (14)C-methane. At the subconvulsive dose, 40% of the administered radioactivity was excreted in the urine. The percentage of urinary excretion of (14)C from higher doses was less, but the net amount excreted was slightly higher.

Undiluted methyl hydrazine applied to dog skin at doses of 14.7-264.5 mg/kg was detected in the blood within 30 sec following application.

For more Absorption, Distribution and Excretion (Complete) data for METHYLHYDRAZINE (7 total), please visit the HSDB record page.

Methylhydrazine is primarily used as a high-energy fuel in military applications, as a rocket propellant and fuel for thrusters, and as fuel for small electrical power generating units. Methylhydrazine is also used as a chemical intermediate and as a solvent.

Used as a rocket fuel, solvent, and chemical intermediate; [ACGIH]

Solvent

In synthesis of ceftriaxone, an antibiotic

In rocket fuel; intermediate in chemical syntheses

Used as a chemical intermediate for the synthesis of difenzoquat methosulphate; procarbazine.

(1977) AT LEAST 4.54X10+7 G

(1982) NOT PRODUCED COMMERCIALLY IN USA

Monomethylhydrazine is prepared from primary amines through substituted ureas by treatment with nitrous acid, reduction and hydrolysis with concentrated hydrochloric acid.

Monomethylhydrazine is produced commercially in the Raschig process by reaction of chloramine with methylamine. /In the Raschig process sodium hypochlorite (obtained by reaction of chlorine with sodium hydroxide) is used to oxidize ammonia. Two steps are involved in the oxidation. In the first, carried out at about 5 °C, chloramine is formed by a fast reaction. ...The reaction mixture is then mixed with methylamine/... .

Ammonia + methylamine (chlorination/dehydrochlorination)

Hydrazine, methyl-: ACTIVE

PREPN OF SULFATE: ... AUDRIETH, DIAMOND; J AM CHEM SOC 76: 4869 (1954). /METHYLHYDRAZINE SULFATE/