Carbamic acid, N-methyl-N-nitroso-, ethyl ester

132.118

132.12

210-432-3

741GDM4803

2860

2811|3082

DTXSID4021472

C29829

Yellow to pink oil|Light colored liquid

2928000090

58.97000

0.44

N-nitroso-n-methylurethane is a solid.

1.133 g/cm³ @ Temp: 20 °C

70 °C @ Press: 27 Torr

38.6±22.6 °C

1.463

36.99g/L(24 ºC)

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practicable to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired. ... Facilities for dispensing ... shoul

1.18 mm Hg at 25 deg C /extrapolated (12 mm Hg at 63 deg C)/

LD50 oral in rat: 180mg/kg

The material is unstable and explodes if distilled at ambient pressure, or may become explosive if stored above 15 deg C.

Sweet smelling

Henry's Law constant = 5.54X10-6 atm-cu m/mol at 25 °C (est)

When heated to decomposition it emits toxic fumes of NOx|1 mg/L approximately = 185 ppm; 1 ppm approximately = 5.4 mg/cu m|Hydroxyl radical reaction rate constant = 5.92X10-12 cu cm/molec-sec at 25 °C (est)

No rapid reaction with air. No rapid reaction with water.

Azo, Diazo, Azido, Hydrazine, and Azide Compounds

N-NITROSO-N-METHYLURETHANE is a N-nitrosated carbamate ester. Incompatible with strong acids and bases. Especially incompatible with strong reducing agents such as hydrides. Flammable gaseous hydrogen may be produced by the combination with active metals or nitrides Incompatible with oxidizing acids, peroxides, and hydroperoxides.

I

2810

3

5-36/37/38-40

23-35-45-53

FC6300000

May become explosive if stored above 15 deg C.

P201, P202, P261, P264, P270, P271, P280, P281, P301+P310, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P321, P330, P332+P313, P337+P313, P362, P403+P233, P405, P501

H301

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U178, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.|A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.|PRECAUTIONS FOR "CARCINOGENS": There is no universal method of disposal that has been proved satisfactory for all carcinogenic compounds & specific methods of chem destruction ... published have not been tested on all kinds of carcinogen-containing waste. ... Summary of avail methods & recommendations ... /given/ must be treated as guide only. /Chemical Carcinogens/|PRECAUTIONS FOR "CARCINOGENS": Total destruction ... by incineration may be only feasable method for disposal of contaminated laboratory waste from biological expt. However, not all incinerators are suitable. ... Most efficient type ... is probably the gas-fired type, in which a first-stage combustion with a less than stoichiometric air:fuel ratio is followed by a second stage with excess air. Some ... are designed to accept ... aqueous & organic-solvent solutions, otherwise it is necessary ... to absorb soln onto suitable combustible material, such as sawdust. Alternatively, chem destruction may be used, esp when small quantities ... are to be destroyed in laboratory. /Chemical Carcinogens/|For more Disposal Methods (Complete) data for N-Nitroso-N-methylurethane (7 total), please visit the HSDB record page.

N-Nitroso-N-methylurethane (NMUT) is highly reactive. It reacts easily with various nucleophiles, especially with thio groups.

WHO; Environ Health Criteria 5: Nitrates, Nitrites, and N-Nitroso Compounds (1978). EHC are designed for scientists and administrators responsible for the establishment of safety standards and regulations and provide basic scientific risk evaluations of a wide range of chemicals and groups of chemicals.

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. For electric vehicles or equipment, ERG Guide 147 (lithium ion batteries) or ERG Guide 138 (sodium batteries) should also be consulted. (ERG, 2016)|Carcinogens, Mutagens, Flammable - 2nd degree, Reactive - 1st degree

|Danger|H301 (100%): Toxic if swallowed [Danger Acute toxicity, oral]|P201, P202, P261, P264, P270, P271, P280, P281, P301+P310, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P321, P330, P332+P313, P337+P313, P362, P403+P233, P405, and P501|The GHS information provided by 1 company from 1 notification to the ECHA C&L Inventory.|H301: Toxic if swallowed [Danger Acute toxicity, oral]

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: SMALL FIRE: Dry chemical, CO2 or water spray. LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. Move containers from fire area if you can do it without risk. Dike fire-control water for later disposal; do not scatter the material. FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2016)

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids. SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above. FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. (ERG, 2016)

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. (ERG, 2016)|PRECAUTIONS FOR "CARCINOGENS": ... Dispensers of liq detergent ... safety pipettes ... for all pipetting. ... In animal laboratory ... protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators ... when working with particulates or gases, & disposable plastic aprons ... gowns ... /should be/ of distinctive color. /Chemical Carcinogens/

Combustible when exposed to heat, sparks, open flame, and powerful oxidizers.

Explodes when heated.|The material is unstable and explodes if distilled at ambient pressure, or may become explosive if stored above 15 °C.

PRECAUTIONS FOR "CARCINOGENS": A high-efficiency particulate arrestor (HEPA) or charcoal filters can be used to minimize amt of carcinogen in exhausted air ventilated safety cabinets, lab hoods, glove boxes or animal rooms. ... Filter housing that is designed so that used filters can be transferred into plastic bag without contaminating maintenance staff is avail commercially. Filters should be placed in plastic bags immediately after removal. ... The plastic bag should be sealed immediately. ... The sealed bag should be labelled properly. ... Waste liquids ... should be placed or collected in proper containers for disposal. The lid should be secured & the bottles properly labelled. Once filled, bottles should be placed in plastic bag, so that outer surface ... is not contaminated. ... The plastic bag should also be sealed & labelled. ... Broken glassware ... should be decontaminated by solvent extraction, by chemical destruction, or in specially designed incinerators. /Chemical Carcinogens/|Decontamination of N-nitrosamine contaminated glassware /was described/. /N-nitrosamines/

PRECAUTIONS FOR "CARCINOGENS": Smoking, drinking, eating, storage of food or of food & beverage containers or utensils, & the application of cosmetics should be prohibited in any laboratory. All personnel should remove gloves, if worn, after completion of procedures in which carcinogens have been used. They should ... wash ... hands, preferably using dispensers of liq detergent, & rinse ... thoroughly. Consideration should be given to appropriate methods for cleaning the skin, depending on nature of the contaminant. No standard procedure can be recommended, but the use of organic solvents should be avoided. Safety pipettes should be used for all pipetting. /Chemical carcinogens/|PRECAUTIONS FOR "CARCINOGENS": In animal laboratory, personnel should remove their outdoor clothes & wear protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... Clothing should be changed daily but ... discarded immediately if obvious contamination occurs ... /also,/ workers should shower immediately. In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide additional protection. If gowns are of distinctive color, this is a reminder that they should not be worn outside of lab. /Chemical carcinogens/|PRECAUTIONS FOR "CARCINOGENS": ... Operations connected with synthesis & purification ... should be carried out under well-ventilated hood. Analytical procedures ... should be carried out with care & vapors evolved during ... procedures should be removed. ... Expert advice should be obtained before existing fume cupboards are used ... & when new fume cupboards are installed. It is desirable that there be means for decreasing the rate of air extraction, so that carcinogenic powders can be handled without ... powder being blown around the hood. Glove boxes should be kept under negative air pressure. Air changes should be adequate, so that concn of vapors of volatile carcinogens will not occur. /Chemical Carcinogens/|PRECAUTIONS FOR "CARCINOGENS": Vertical laminar-flow biological safety cabinets may be used for containment of in vitro procedures ... provided that the exhaust air flow is sufficient to provide an inward air flow at the face opening of the cabinet, & contaminated air plenums that are under positive pressure are leak-tight. Horizontal laminar-flow hoods or safety cabinets, where filtered air is blown across the working area towards the operator, should never be used. ... Each cabinet or fume cupboard to be used ... should be tested before work is begun (eg, with fume bomb) & label fixed to it, giving date of test & avg air-flow measured. This test should be repeated periodically & after any structural changes. /Chemical Carcinogens/|For more Preventive Measures (Complete) data for N-Nitroso-N-methylurethane (10 total), please visit the HSDB record page.

PRECAUTIONS FOR "CARCINOGENS": Procurement ... of unduly large amt ... should be avoided. To avoid spilling, carcinogens should be transported in securely sealed glass bottles or ampoules, which should themselves be placed inside strong screw-cap or snap-top container that will not open when dropped & will resist attack from the carcinogen. Both bottle & the outside container should be appropriately labelled. ... National post offices, railway companies, road haulage companies & airlines have regulations governing transport of hazardous materials. These authorities should be consulted before ... material is shipped. /Chemical Carcinogens/|PRECAUTIONS FOR "CARCINOGENS": When no regulations exist, the following procedure must be adopted. The carcinogen should be enclosed in a securely sealed, watertight container (primary container), which should be enclosed in a second, unbreakable, leakproof container that will withstand chem attack from the carcinogen (secondary container). The space between primary & secondary container should be filled with absorbent material, which would withstand chem attack from the carcinogen & is sufficient to absorb the entire contents of the primary container in the event of breakage or leakage. Each secondary container should then be enclosed in a strong outer box. The space between the secondary container & the outer box should be filled with an appropriate quantity of shock-absorbent material. Sender should use fastest & most secure form of transport & notify recipient of its departure. If parcel is not received when expected, carrier should be informed so that immediate effort can be made to find it. Traffic schedules should be consulted to avoid ... arrival on weekend or holiday ... /Chemical Carcinogens/

Nitrosomethylurethane vapor is highly irritating to eyes & resp tract & direct contact with skin causes blistering.

U178; A toxic waste when a discarded commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate.

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 1 lb or 0.454 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV.D.3.b).

U178; As stipulated in 40 CFR 261.33, when N-nitroso-n-methylurethane, 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 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).

Lung injury in rabbits was induced with N-nitroso-N-methylurethane (NMU) and 6 of 17 NMU-injured rabbits were treated with 100 mg/kg surfactant. All rabbits were ventilated for 2 hr, and large aggregate alveolar surfactant was isolated by centrifugation. In vivo function of the large aggregate surfactant was evaluated by treatment of preterm surfactant-deficient rabbits at 27 days gestation. Surfactant from NMU-injured lungs increased compliance from 0.37 +/- 0.01 in control preterm rabbits to 0.71 +/- 0.05, a value significantly higher than found for the surfactant used for treatment (0.55 +/- 0.04) (p < 0.05). The minimal surface tensions of large aggregate surfactant and the surfactant used for treatment (0.1 mg lipid/mL) were evaluated for inhibition by plasma proteins. Surfactant from NMU-injured and surfactant-treated rabbits was more resistant to inhibition (minimal surface tension, 5.7 +/- 3.9 dyne/cm in the presence of 0.6 mg/mL plasma protein) than the surfactant used for treatment (19.7 +/- 0.8 dyne/cm). These results indicate that after exposure to the injured lung, the function of the surfactant used for treatment was enhanced and made less sensitive to plasma inhibition of the surface-tension-lowering properties of surfactant. These changes probably result from the association of endogenous surfactant components with exogenous surfactant.|Subcutaneous injection of N-nitroso-N-methylurethane (NNNMU) produces an acute lung injury mimicking the adult respiratory distress syndrome. NNNMU-injured rats treated with intratracheal Survanta, 100 mg phospholipid/kg bw, air, or normal saline were observed for 24 hr. 24 hr after treatment survival among Survanta-treated rats was significantly greater than for air- and saline-treated rats (9/15 vs. 2/15 and 3/15, respectively). The alveolar-to-arterial O2 gradient was lower in Survanta-treated than in either air- or saline-treated rats during the 24 hr period. Analysis of bronchoalveolar lavage fluid revealed a higher phospholipid: protein ratio (1.73 +/- 0.31 Survanta-treated, 0.20 +/- 0.05 air control, and 0.41 +/- 0.17 saline control) and a more normal phospholipid composition among treated than control rats. Minimum dynamic surface tension was significantly lower among treated rats (10.9 +/- 2.9 dyn/cm) than air and saline control rats (36.0 +/- 0.6 and 35.8 +/- 1.0 dyn/com, respectively). In vitro mixing of surfactant with pulmonary edema proteins significantly raised the minimum surface tension of surfactant from a group of Survanta-treated, NNNMU-injured rats (8.7 +/- 3.5 dyn/cm before and 32.0 +/- 0.5 dyn/cm after mixing). Intratracheal Survanta shows a beneficial effect on physiologic parameters and biochemical and functional characteristics of alveolar surfactant for 24 hr in rats with NNNMU-induced acute lung injury.|The effects of minute amounts of cigarette smoke with or without nebulized N-nitroso-N-methylurethane (NMUT) on the respiratory epithelia of mice were examined. The first group received the combination of NMUT nebulization and cigarette smoke inhalation, the second group NMUT nebulization only, the third group cigarette smoke inhalation only and the fourth group no treatment. The first group showed squamous cell carcinomas in the nasal cavity (4 out of 10 mice), trachea (4 out of 10 mice) and lung (2 out of 10 mice). In the second group squamous cell carcinomas with keratosis were found in the nasal cavity (2 out of 10 mice) and in the lung (1 out of 10 mice). Furthermore, basal cell hyperplasias, squamous metaplasias and dysplastic changes were found in these two groups. The third group showed basal cell hyperplasias and squamous metaplasias in the nasal cavity and hypertrophy of Clara cells. No marked changes of epithelia of the respiratory tract in the fourth group were seen. Adenomas and adenocarcinomas were not found in any group. Statistically, there is a significant difference in the incidence of dysplastic change of the trachea between group 1 and group 2 (P < 0.05). These results suggest that minute amounts of cigarette smoke, in combination with carcinogens, may have cocarcinogenic action and that squamous cell carcinoma may pass through the course of basal cell hyperplasia, squamous metaplasia and dysplastic change of the epithelia.|Admin of 7.5 mg/kg body wt of N-nitroso-N-methylurethane subcutaneously to rabbits decreased disaturated phosphatidylcholine, phosphatidylglycerol, & increased the minimum surface tension of alveolar lavage return. Myoinositol supplementation (3-7 g/kg/day) of N-nitroso-N-methylurethane treated animals largely prevented both the decrease in disaturated phosphatidylcholine, & the increase in minimum surface tension.|For more Interactions (Complete) data for N-Nitroso-N-methylurethane (7 total), please visit the HSDB record page.

LD50 Rat oral 180 mg/kg|LD50 Rat iv 4 mg/kg|LD50 Mouse ip 37 mg/kg

/PLANTS/ The combination of gamma ray & N-nitroso-N-methylurethane treatment of pea & barley seeds exerted a synergistic & antagonistic action on mutagenic & toxic lethal activity, respectively.|/PLANTS/ In the root tip cells of normal & trigenic leaf mutants of garden peas, caffeine potentiated N-nitroso-N-methylurethane induced S-phase-dependent chromosome damage & x-ray nondelayed, S-independent effects. The potentiation was lower at 31 °C than at 16 °C.|/PLANTS/ Winter wheat plants treated with NMU /N-nitroso-N-methylurethane/ retained the toxic effects for quite some time, though the toxicity decreased with time. The height of the NMU-treated plants were lower than the controls. Thus, treatment of seeds with NMU results in plants with lower height.

N-Nitroso-N-methylurethane production and use as a cancer research chemical(1,2) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 40(SRC), determined from a structure estimation method(2), indicates that N-nitroso-N-methylurethane is expected to have very high mobility in soil(SRC). Volatilization of N-nitroso-N-methylurethane from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 5.5X10-6 atm-cu m/mole(SRC), based upon its vapor pressure, 1.18 mm Hg(3), and water solubility, 37,000 mg/L(4). N-nitroso-N-methylurethane is expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). Biodegradation data in soil were not available(SRC, 2010).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 40(SRC), determined from a structure estimation method(2), indicates that N-nitroso-N-methylurethane is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 5.5X10-6 atm-cu m/mole(SRC), derived from its vapor pressure, 1.18 mm Hg(4), and water solubility, 37,000 mg/L(5). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 8 and 60 days, respectively(SRC). According to a classification scheme(6), an estimated BCF of 3(SRC), from an estimated log Kow of 1.22(7) and a regression-derived equation(8), suggests the potential for bioconcentration in aquatic organisms is low(SRC). In alkaline conditions, N-nitroso-N-methylurethane decomposes to diazomethane(9). The hydrolysis rate constant for N-nitroso-N-methylurethane in water was determined to be 0.029/hour under neutral conditions and 2900/M/hour under basic conditions; this corresponds to a half-life at pH 7 and 25 °C of 24 hours(10). Biodegradation data in water were not available(SRC, 2010).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), N-nitroso-N-methylurethane, which has a vapor pressure of 1.18 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase N-nitroso-N-methylurethane 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 3 days(SRC), calculated from its rate constant of 5.9X10-12 cu cm/molecule-sec at 25 °C(3). N-nitroso-N-methylurethane contains chromophores that absorb at wavelengths >290 nm(4) and therefore may be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of N-nitroso-N-methylurethane with photochemically-produced hydroxyl radicals has been estimated as 5.9X10-12 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 3 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). In alkaline conditions, N-nitroso-N-methylurethane decomposes to diazomethane(2). The hydrolysis rate constant for N-nitroso-N-methylurethane in water was determined to be 0.029/hour under neutral conditions and 2900/M/hour under basic conditions; this corresponds to a half-life at pH 7 and 25 °C of 24 hours(3). N-nitroso-N-methylurethane contains chromophores that absorb at wavelengths >290 nm(4) and therefore may be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated in fish for N-nitroso-N-methylurethane(SRC), using an estimated log Kow of 1.22(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of N-nitroso-N-methylurethane can be estimated to be 40(SRC). According to a classification scheme(2), this estimated Koc value suggests that N-nitroso-N-methylurethane is expected to have very high mobility in soil.

The Henry's Law constant for N-nitroso-N-methylurethane is estimated as 5.5X10-6 atm-cu m/mole(SRC) derived from its vapor pressure, 1.18 mm Hg(1), and water solubility, 37,000 mg/L(2). This Henry's Law constant indicates that N-nitroso-N-methylurethane is expected to volatilize from water surfaces(3). 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 8 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)(3) is estimated as 60 days(SRC). N-Nitroso-N-methylurethane's estimated Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). The potential for volatilization of N-nitroso-N-methylurethane from dry soil surfaces may exist(SRC) based upon its vapor pressure(1).

Occupational exposure to N-nitroso-N-methylurethane may occur through inhalation and dermal contact with this compound at workplaces where N-nitroso-N-methylurethane is produced or used. (SRC)

Highly reactive chemicals that introduce alkyl radicals into biologically active molecules and thereby prevent their proper functioning. Many are used as antineoplastic agents, but most are very toxic, with carcinogenic, mutagenic, teratogenic, and immunosuppressant actions. They have also been used as components in poison gases. (See all compounds classified as Alkylating Agents.)

Methylation of nucleic acids in vivo and in vitro has been demonstrated; the main reaction product is 7-methylguanine, and 3-methyladenine has been found to be another. Methylation also occurs in /SRP: non-target/ organs.

In this study, the biochemical mechanisms by which N-nitroso-N-methylurethane (NNMU) induces acute lung injury are examined. Polymorphonuclear neutrophil infiltration into the lungs first appears in the bronchoalveolar lavage (BAL) fluid 24 hr after NNMU injection (10.58 +/- 3.00% of total cells; P < 0.05 vs. control animals). However, NNMU-induced elevation of the alveolar-arterial O2 difference requires 72 hr to develop. Daily intraperitoneal injections of the inducible nitric oxide (. NO) synthase (iNOS)-selective inhibitor aminoguanidine (AG) initiated 24 hr after NNMU administration improve the survival of NNMU-treated animals. However, AG administration initiated 48 or 72 hr after NNMU injection does not significantly improve the survival of NNMU-treated animals. These results suggest that NO participates in events that occur early in NNMU-induced acute lung injury. BAL cells isolated from rats 24 and 48 hr after NNMU injection produce elevated NO and express iNOS during a 24-hr ex vivo culture. AG attenuates NO production but does not affect iNOS expression, whereas actinomycin D prevents iNOS expression and attenuates NO production by BAL cells during this ex vivo culture. These results suggest that NNMU-derived BAL cells can stimulate iNOS expression and NO production during culture. In 48-hr NNMU-exposed rats, iNOS expression is elevated in homogenates of whole lavaged lungs but not in BAL cells derived from the same lung. These findings suggest that the pathogenic mechanism by which NNMU induces acute lung injury involves BAL cell stimulation of iNOS expression and NO production in lung tissue.

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. (ERG, 2016)

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]: Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim calm and warm. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. (ERG, 2016)

/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Isocyanates, aliphatic thiocyanates, and related compounds/|/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Monitor for seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patent can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . /Isocyanates, aliphatic thiocyanates, and related compounds/|/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Treat exposure to Lethane 60 Lethane 384, Thanite, methyl, ethyl, or isopropyl thiocyanates with the cyanide antidote kit. ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Isocyanates, aliphatic thiocyanates, and related compounds/|/SRP:/ Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Nitrates, nitrites, and related compounds/|For more Antidote and Emergency Treatment (Complete) data for N-Nitroso-N-methylurethane (6 total), please visit the HSDB record page.

/SIGNS AND SYMPTOMS/ Nitrosomethylurethane vapor is highly irritating to eyes & resp tract & direct contact with skin causes blistering. These effects may be delayed & subside slowly.|/CASE REPORTS/ One report is of several chemists exposed to liq, vapors of N-nitroso-N-methylurethane. The effects from skin & vapor exposure were slow-healing skin ulcers, conjunctivitis, & respiratory problems (cough & hoarseness) which slowly became more severe. Those exposed only to the vapors had conjunctivitis & respiratory problems (less severe).|/CASE REPORTS/ Blurring of vision is associated with inflammation of the eyes and is presumably attributable to edema of the corneal epithelium. ... A chemist exposed presumably only to the vapors felt burning and scratching pain in the eyes after about two and one-half hr. Exam showed hyperemia, blepharospasm, chemosis, and keratitis epithelialis. This was followed by partial loss of corneal epithelium. Discomfort was greatest in the early stages. The eyes were entirely normal five months later.|/OTHER TOXICITY INFORMATION/ More than one hundred N-nitroso compounds have been tested for carcinogenicity and about 75-80% have been found to cause cancer in animals. Although there is no definite evidence that ... N-nitrosocompounds have induced cancer in man, several suggestive epidemiological correlations have been reported and there is no reason to suppose that man is not susceptible. /N-nitroso compounds/

Methylnitrosourethane

Carbamic acid, N-methyl-N-nitroso-, ethyl ester: ACTIVE|S - indicates a substance that is identified in a final Significant New Use Rule.|No evidence was found to show it is produced commercially except as a research chemical ...|Although previously published methods for the destruction of nitrosamines also degrade nitrosamides, the products in the latter case may be carcinogenic or otherwise harmful.

Fire Hazards -> Carcinogens, Mutagens, Flammable - 2nd degree, Reactive - 1st degree