N-Nitroso-N-methylvinylamine

86.09250

86.09

4F13H2637M

137906

2810|3082

DTXSID3042211

C44419

Yellow liquid

2928000090

32.67000

0.74310

N-nitrosomethylvinylamine is a very volatile yellow liquid. (NTP, 1992)

0.94g/cm3

47-48 °C @ Press: 30 Torr

45.5ºC

1.436

SOL IN WATER (3%) & IN ORG SOLVENTS & LIPIDS

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

8.96 mm Hg at 25 °C (est)

LD50 oral in rat: 24mg/kg

Henry's Law constant = 3.6X10-6 atm-cu m/mol at 25 °C (est)

Hydroxyl radical reaction rate constant = 1.70X10-11 cu cm/molecule-sec at 25 °C (est)

Water soluble but relatively unstable in water (NTP, 1992).

Azo, Diazo, Azido, Hydrazine, and Azide Compounds

Water-Reactive

II

6.1(a)

UN 2810

UNSTABLE; CONCN DECR OF MORE THAN 10% HAS BEEN OBSERVED IN AQ SOLN OVER 24 HR; LIGHT SENSITIVE, ESP TO UV LIGHT

P201, P202, P264, P270, P281, P301+P310, P308+P313, P321, P330, P405, P501

H300

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number P084, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.|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 ... 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/|PRECAUTIONS FOR "CARCINOGENS": HEPA (high-efficiency particulate arrestor) filters ... can be disposed of by incineration. For spent charcoal filters, the adsorbed material can be stripped off at high temp & carcinogenic wastes generated by this treatment conducted to & burned in an incinerator. ... LIQUID WASTE: ... Disposal should be carried out by incineration at temp that ... ensure complete combustion. SOLID WASTE: Carcasses of lab animals, cage litter & misc solid wastes ... should be disposed of by incineration at temp high enough to ensure destruction of chem carcinogens or their metabolites. /Chemical Carcinogens/|For more Disposal Methods (Complete) data for N-Nitrosomethylvinylamine (6 total), please visit the HSDB record page.

USEPA; Ambient Water Quality Criteria Doc: Nitrosamines (1980) EPA-440/5-80-064|USEPA; Environmental Assessment of Atmospheric Nitrosamines, MTR-7512, Contract No 68-02-1495 (1976)|WHO; Environ Health Criteria 5: Nitrates, Nitrites, and N-Nitroso Compounds (1978)|McGaughy R et al; Mutat Res 185 (1-2): 1-195 (1987); A review and analysis of the literature of selected chemicals and the establishment of the gene-tox carcinogen data base.|For more Special Reports (Complete) data for N-Nitrosomethylvinylamine (6 total), please visit the HSDB record page.

Flash point data for this chemical are not available; however it is probably combustible. (NTP, 1992)

|Danger|H300: Fatal if swallowed [Danger Acute toxicity, oral]|P201, P202, P264, P270, P281, P301+P310, P308+P313, P321, P330, P405, and P501

Excerpt from ERG Guide 153 [Substances - Toxic and/or Corrosive (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)

SMALL SPILLS AND LEAKAGE: If you should spill this chemical, use absorbent paper to pick up all liquid spill material. Seal the absorbent paper, as well as any of your clothing which may be contaminated, in a vapor-tight plastic bag for eventual disposal. Wash any surfaces you may have contaminated with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned. STORAGE PRECAUTIONS: You should protect this material from exposure to light, and store it in a refrigerator. (NTP, 1992)

MINIMUM PROTECTIVE CLOTHING: If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves. RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with a combination filter cartridge, i.e. organic vapor/acid gas/HEPA (specific for organic vapors, HCl, acid gas, SO2 and a high efficiency particulate filter). (NTP, 1992)|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/|MINIMUM PROTECTIVE CLOTHING: If Tyvek-type disposable protective clothing is not worn during handling of this chemical, wear disposable Tyvek-type sleeves taped to your gloves.|RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with a combination filter cartridge, i.e. organic vapor/acid gas/HEPA (specific for organic vapors, HCl, acid gas, SO2 and a high efficiency particulate filter).

Fires involving this material can be controlled with a dry chemical, carbon dioxide or Halon extinguisher.

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/|Nitrosamine residues generated in laboratory research or accidental spills in research laboratories and diluted to concn of 10 mg/l or less are rapidly reduced to innocuous amines, ammonia, or alcohols by aluminum-nickel alloy powder and aqueous alkali. The method is applicable to a variety of media (water, mineral oil, olive oil, dimethylsulfoxide, soln of agar gel) but is not recommended for use with nitrosamines in acetone or dichloromethane because reactions are slow and incomplete. After the reduced reaction mixture is filtered, the liquid is disposed of by pouring it over sufficient absorbent material to convert it to a solid waste for incineration. /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 and 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-Nitrosomethylvinylamine (9 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/

P084; An acute hazardous 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 10 lb or 4.54 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).

P084; As stipulated in 40 CFR 261.33, when N-nitrosomethylvinylamine, 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)).

IDENTIFICATION AND USE: N-nitrosomethylvinylamine (NMVA) is a yellow liquid. HUMAN STUDIES: There are no data available. ANIMAL STUDIES: Of a group of 19 rats given NMVA in drinking-water at doses of 0.3 or 0.6 mg/kg bw/day, 2 developed papillomas and 17 developed nodular and widely distributed squamous-cell carcinomas of the esophagus. In addition, 4 animals had carcinomas of the tongue and 5 animals had carcinomas of the pharynx; 8 rats showed bile-duct proliferation and cysts in the liver. The average induction time for the tumors of the upper digestive tract was 390 or 270 days, respectively. The average total dose that caused tumors in 50% of the animals was 0.11 or 0.16 g/kg bw. NMVA causes X-linked recessive lethal mutations in Drosophila melanogaster.

LD50 Rat oral 24 mg/kg|LC50 Rat inhalation 22 mg/kg

N-Nitrosomethylvinylamine may be available for research purposes(1); however, no evidence was found that N-nitrosomethylvinylamine is produced commercially(2).

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-nitrosomethylvinylamine is expected to have very high mobility in soil(SRC). Volatilization of N-nitrosomethylvinylamine from moist soil surfaces is expected(SRC) given an estimated Henry's Law constant of 3.6X10-6 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). N-Nitrosomethylvinylamine is expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 8.96 mm Hg at 25 °C(3). Biodegradation data in soil were not available(SRC, 2018).|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-nitrosomethylvinylamine 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 3.6X10-6 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 10 and 70 days, respectively(SRC). N-Nitrosomethylvinylamine is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). According to a classification scheme(4), an estimated BCF of 3(SRC), from an estimated log Kow of -0.28(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low. Biodegradation data in water were not available(SRC, 2018).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), N-nitrosomethylvinylamine, which has an estimated vapor pressure of 8.96 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase N-nitrosomethylvinylamine 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 23 hours(SRC), calculated from its rate constant of 1.7X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). N-Nitrosomethylvinylamine absorbs light 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-nitrosomethylvinylamine with photochemically-produced hydroxyl radicals has been estimated as 1.7X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 23 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). N-Nitrosomethylvinylamine is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). N-Nitrosomethylvinylamine absorbs light at wavelengths >290 nm(3) and, therefore, may be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated in fish for N-nitrosomethylvinylamine(SRC), using an estimated log Kow of -0.28(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low.

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

The Henry's Law constant for N-nitrosomethylvinylamine is estimated as 3.6X10-6 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that N-nitrosomethylvinylamine is expected to volatilize from water surfaces(2). 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)(2) is estimated as 10 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)(2) is estimated as 70 days(SRC). N-Nitrosomethylvinylamine's Henry's Law constant indicates that volatilization from moist soil surfaces may occur(SRC). N-Nitrosomethylvinylamine may volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 8.96 mm Hg(3).

A preliminary report indicates N-nitrosomethylvinylamine may be present in apple brandy(1).

Exposure to N-nitrosomethylvinylamine is limited to its use in research. Monitoring data indicate that the general population is not likely to be exposed to N-nitrosomethylvinylamine. (SRC)

ACUTE/CHRONIC HAZARDS: This compound is highly toxic by ingestion and inhalation. When heated to decomposition, this compound emits toxic fumes of NOx. (NTP, 1992)|Carcinogens

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas. INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing. INGESTION: If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Generally, the induction of vomiting is NOT recommended outside of a physician's care due to the risk of aspirating the chemical into the victim's lungs. However, if the victim is conscious and not convulsing and if medical help is not readily available, consider the risk of inducing vomiting because of the high toxicity of the chemical ingested. Ipecac syrup or salt water may be used in such an emergency. IMMEDIATELY transport the victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. OTHER: Since this chemical is a known or suspected carcinogen you should contact a physician for advice regarding the possible long term health effects and potential recommendation for medical monitoring. Recommendations from the physician will depend upon the specific compound, its chemical, physical and toxicity properties, the exposure level, length of exposure, and the route of exposure. (NTP, 1992)

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 the 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. /Organic bases/Amines and related compounds/|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 ... . Anticipate 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 ... . Cover skin burns with dry sterile dressings after decontamination ... . /Organic bases/Amines and related compounds/|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 ... . Monitor cardiac rhythm and treat arrhythmias as 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. If patient is unresponsive to these measures, vasopressors may be helpful. Watch for signs of fluid overload ... . Administer 1% solution methylene blue if patient is symptomatic with severe hypoxia, cyanosis, and cardiac compromise not responding to oxygen ... . Treat seizures with diazepam (Valuim) or lorazepam (Ativan) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Organic bases/Amines and related compounds/|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-Nitrosomethylvinylamine (6 total), please visit the HSDB record page.

N-nitroso-N-methylvinylamine

Gas chromatography/thermal energy analysis, high pressure liquid chromatography/thermal energy analysis and gas chromatography/mass spectrometry have been used for the analysis of NMVA.|Volatile N-nitrosamines were confirmed in foods at concentrations of less than 10 micrograms/kg by full scan low resolution mass spectrometry. Ground samples were vacuum-distilled from mineral oil and condensed in liquid nitrogen-cooled vapor traps. The thawed distillate was extracted, the extract was cleaned up and concentrated, and the N-nitrosamine content was determined by combined gas chromatograph-thermal energy analysis. Positive samples were further cleaned up, trapped from a gas chromatographic column, and purged into a gas chromatograph-mass spectrometer for qualitative confirmation by full scan low resolution mass spectrometry. This procedure was applied to foods spiked at 1 microgram/kg and to fried commercial bacons with volatile N-nitrosamine contents of 2 to 5 micrograms/kg. /N-Nitrosamines/

A group-selective method for the determination of total N-nitroso compounds (NOC) has been adapted for analysing human urine samples. Nitrate was first removed from urine by an anion-exchange procedure that prevented the significant loss of various added reference NOC and unidentified urinary NOC. The total NOC were then determined by injecting the urine sample (nitrate content less than 1 mmol l-1) or anion-exchange eluate into refluxing ethyl acetate containing either acetic acid for determining heat and acetic acid labile thermal energy analyser responsive compounds (TAC) or into hydrogen bromide for the determination of TAC and NOC. The nitrogen monoxide levels released were measured using thermal energy analysis with chemiluminescence detection, and the differnce between the two determinations represented the concentrations of NOC. The optimum conditions for preventing artefactual nitrosation in urine samples by the addition of sodium hydroxide or sulphamic acid without decomposition of NOC were determined. The influence of time and storage conditions on NOC stability was investigated. Fifteen urine samples collected from volunteers dosed with proline were analysed for total NOC and N-nitrosamino acids revealing a preponderance of unknown NOC. The determination of total NOC in human urine using this group-selective method offers a new approach to the estimation of human exposure to NOC and to isolate hitherto unknown NOC and their metabolites. /N-nitroso cmpd/

Health Hazards -> Carcinogens