nitrogen

This chemical does not meet GHS hazard criteria for 4.7% (47 of 1001) of reports.

H280 (70.2%): Contains gas under pressure; may explode if heated [Warning Gases under pressure]

H281 (26%): Contains refrigerated gas; may cause cryogenic burns or injury [Warning Gases under pressure]

P282, P336+P317, P403, and P410+P403 (click each P-code to see the statement)

Aggregated GHS information provided per 1001 reports by companies from 11 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 47 of 1001 reports by companies.

There are 10 notifications provided by 954 of 1001 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

H280: Contains gas under pressure; may explode if heated [Warning Gases under pressure]

P410+P403</a, and a href="https://pubchem.ncbi.nlm.nih.gov/ghs/#P410+P403">P410+P403 (click each P-code to see the statement)

H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]

H401: Toxic to aquatic life [Hazardous to the aquatic environment, acute hazard]

P273, P301+P316, P331, P405, and P501 (click each P-code to see the statement)

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

ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Refer for medical attention .

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

Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]:

Refer to the "General First Aid" section. Specific First Aid: Clothing frozen to the skin should be thawed before being removed. In case of contact with liquefied gas, only medical personnel should attempt thawing frosted parts. (ERG, 2024)

INHALATION: remove to fresh air; apply artificial respiration if breathing has stopped; call physician.

EYES: treat for frostbite burns caused by liquid.

SKIN: treat for frostbite; soak in lukewarm water. (USCG, 1999)

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:

· Clothing frozen to the skin should be thawed before being removed.

· In case of contact with liquefied gas, only medical personnel should attempt thawing frosted parts.

Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]:

Use extinguishing agent suitable for type of surrounding fire. If it can be done safely, move undamaged containers away from the area around the fire. Damaged cylinders should be handled only by specialists.

FIRE INVOLVING TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Do not direct water at source of leak or safety devices; icing may occur. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. (ERG, 2024)

In case of fire in the surroundings, use appropriate extinguishing media. In case of fire: keep cylinder cool by spraying with water.

In case of fire in the surroundings, use appropriate extinguishing media.

If material involved in fire: Extinguish fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.) Cool all affected containers with flooding quantiites of water. Apply water from as far a distance as possible. /Nitrogen, compressed/

Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Wear self contained breathing apparatus for fire fighting if necessary.

Extinguish fire using agent suitable for surrounding fire. Use water spray to keep fire-exposed containers cool. /Nitrogen, refrigerated liquid/

Under prolonged exposure to fire or heat the containers may rupture violently and rocket. /Nitrogen, compressed/

· 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.

· Many gases are heavier than air and will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.).

· Ventilate closed spaces before entering, but only if properly trained and equipped.

· Do not touch or walk through spilled material.

· Stop leak if you can do it without risk.

· Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material.

· Do not direct water at spill or source of leak.

· If possible, turn leaking containers so that gas escapes rather than liquid.

· Prevent entry into waterways, sewers, basements or confined areas.

· Allow substance to evaporate.

· Ventilate the area.

CAUTION: When in contact with refrigerated/cryogenic liquids, many materials become brittle and are likely to break without warning.

Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 100 meters (330 feet) in all directions.

LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet).

FIRE: If tank, rail tank car or highway tank 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, 2024)

Immediate precautionary measure

· Isolate spill or leak area for at least 100 meters (330 feet) in all directions.

Large Spill

· Consider initial downwind evacuation for at least 100 meters (330 feet).

· If tank, rail tank car or highway tank 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.

Ventilation. Personal protection: self-contained breathing apparatus.

Ventilation. NEVER direct water jet on liquid. Personal protection: chemical protection suit including self-contained breathing apparatus.

Soak up with inert absorbent material and dispose of as hazardous waste. Keep in suitable, closed containers for disposal.

Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided.

Use personal protective equipment. Avoid breathign vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas.

If liquid nitrogen is spilled or leaked, take the following steps: restrict persons not wearing protective equipment from area of spill or leak until clean-up is complete. Ventilate the area of spill or leak. Stop the leak or move the container to a safe area and allow the liquid to evaporate. If nitrogen gas is leaked, take the following steps: restrict persons not wearing protective equipment from area of leak until clean-up is complete. Stop flow of gas. If source of leak is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place in the open air and repair leak or allow cylinder to empty. Absorb liquids in vermiculite, dry sand, earth, peat, carbon, or a simlar material and deposit in sealed containers. It may be necessary to contain and dispose of this chemical as a hazardous waste. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Contact your Department of Environmental Protection or your regional office of the federal EPA for specific recommendations.

For more Cleanup Methods (Complete) data for Nitrogen, Elemental (6 total), please visit the HSDB record page.

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Avoid contact with skin and eyes. Avoid inhalation of vapor or mist.

SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants. Ensure that the local ventilation moves the contaminant away from the worker.

Leaks in lines and equipment may be detected by painting the suspected sites with soapy water. Leaks will be evident by bubble formation.

Cylinders containing nitrogen have safety devices of either the frangible disc type or frangible disc type backed up with fusible metal, melting at approximately 100 °C (212 °F). Cylinders pressurized 10% of excess of their marked service pressure in accordance with present DOT regulations must be equipped only with safety devices of the unbacked frangible disc type. These safety devices are usually an integral part of the cylinder valve, situated opposite the valve outlet.

For more Preventive Measures (Complete) data for Nitrogen, Elemental (7 total), please visit the HSDB record page.

Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]:

Do not touch or walk through spilled material. Stop leak if you can do it without risk. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Do not direct water at spill or source of leak. If possible, turn leaking containers so that gas escapes rather than liquid. Prevent entry into waterways, sewers, basements or confined areas. Allow substance to evaporate. Ventilate the area. CAUTION: When in contact with refrigerated/cryogenic liquids, many materials become brittle and are likely to break without warning. (ERG, 2024)

Fireproof if in building. Cool. Keep in a well-ventilated room.

Fireproof if in building. Keep in a well-ventilated room.

Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage.

Since liquid nitrogen tends to cause localized oxygen enrichment due to a fractional distillation of air, containers such as formed plastics should not be used even for temporary storage of liquid nitrogen due to the resultant increase combustibility.

Storage temperature for liquid nitrogen: -320 °F.

Store in a cool, dry, well-ventilated location. Outside or detached storage is preferred. /Nitrogen, refrigerated liquid/

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

· Always wear thermal protective clothing when handling refrigerated/cryogenic liquids or solids.

796000 [ppm]

832000 [ppm]

869000 [ppm]

Simple asphyxiant. /A simple asphyxiant may not be assigned a TLV because the limiting factor is the available oxygen./

· Use extinguishing agent suitable for type of surrounding fire.

· If it can be done safely, move undamaged containers away from the area around the fire.

· Damaged cylinders should be handled only by specialists.

Fire Involving Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Cool containers with flooding quantities of water until well after fire is out.

· Do not direct water at source of leak or safety devices; icing may occur.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

On loss of containment this substance can cause suffocation by lowering the oxygen content of the air in confined areas.

On loss of containment this substance can cause serious risk of suffocation when in confined areas.

The liquid may cause frostbite.

The insecticide nitrogen is exempted from the requirements of a tolerance when used after harvest in modified atmospheres for stored product insect control on all food commodities.

Excerpt from ERG Guide 120 [Gases - Inert (Including Refrigerated Liquids)]:

Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids or solids. (ERG, 2024)

Safety glasses or face shield; insulated gloves; long sleeves; trousers worn outside boots or over high-top shoes to shed spilled liquid; self-contained breathing apparatus where insufficient air is present. (USCG, 1999)

Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face respirator with multi-purpose combination (US) or type ABEK (EN 14387) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face air respirator. Use respirators and components tested and approved under appropriate government standars such as NIOSH (US) or CEN (EU).

Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touchign glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

Face shield and safety glasses. Use equipment for eye protection tested and approved under appopriate government standars such as NIOSH (US) or EN 166 (EU).

Safety glasses or face shield; insulated gloves; long sleeves; trousers worn outside boots or over high top shoes to shed spilled liq; self contained breathing apparatus where insufficient air is present.

/When used as a biocide/ the operator must ... be equipped with an escape SCBA to allow safe evacuation from the risk area, if necessary.

Use ventilation.

Cold-insulating gloves.

Wear safety goggles.

Nitrogen appears as a colorless odorless gas. Noncombustible and nontoxic. Makes up the major portion of the atmosphere, but will not support life by itself. Used in food processing, in purging air conditioning and refrigeration systems, and in pressurizing aircraft tires. May cause asphyxiation by displacement of air. Under prolonged exposure to fire or heat containers may rupture violently and rocket.

Nitrogen, refrigerated liquid (cryogenic liquid) appears as colorless odorless liquid. Very cold. Contact may cause frostbite. Nontoxic. Under prolonged exposure to heat or fire the container may rupture violently and rocket. Used to freeze foods, to preserve whole blood and other biologicals, and as a coolant.

Liquid; CBI; Gas Vapor; Other Solid

Colourless, odourless, non-flammable gas

Odorless gas; [Merck Index] Vapor density = approximately the same as air; [HSDB]

ODOURLESS COLOURLESS COMPRESSED GAS.

ODOURLESS COLOURLESS EXTREMELY COLD LIQUID.

Colorless gas

Colorless liquid at -196 °C

Odorless gas

Tasteless

-320.1 °F at 760 mmHg (USCG, 1999)

-195.79 °C (77.36 K)

-195.79 °C @760 [mm Hg]

-354 °F (USCG, 1999)

-210.01 °C (63.14K)

TRIPLE POINT TEMP: 63.1 DEG K; TRIPLE POINT PRESSURE: 0.127 ATM; HEAT OF FUSION: 6.1 CAL/G

-210.01 °C

In water, 1.81X10+4 mg/L at 21 °C

Insoluble in ethanol

Sparingly soluble in water: 100 vol water absorbs 2.4 vol nitrogen at 0 °C; 100 vol water absorbs 1.6 vol nitrogen at 20 °C /gas/

Slightly soluble in water and alcohol

For more Solubility (Complete) data for Nitrogen, Elemental (7 total), please visit the HSDB record page.

18.1 mg/mL at 21 °C

Solubility in water: poor

0.807 at -319.9 °F (USCG, 1999) - Less dense than water; will float

1.251 g/L at 0 °C and 1 atm; ... 0.804 (liquid), and 1.0265 (solid)

Critical density: 0.311 g/cu cm; heat of dissociation of nitrogen molecule (N2): 225.1 kcal/mole

VAPOR DENSITY @ NORMAL TEMP APPROX SAME AS AIR; COLD GAS AS IT COMES FROM LIQ IS HEAVIER THAN AIR /GAS/

Density (at the boiling point of the liquid): 0.808 kg/l

0.808 @ -195.8°C

0.96737 (Air = 1.00)

Relative vapor density (air = 1): 0.97

-236 °C at 1Pa (solid); -232 °C at 10Pa (solid); -226.8 °C at 100Pa (solid); -220.2 °C at 1kPa (solid); -211.1 °C at 10kPa (solid); -195.9 °C at 100kPa (N2)

log Kow = 0.67

Incombustible and unreactive.

7.0 at 100 K; 12.0 at 200 K; 17.9 at 300 K; 22.2 at 400 K; 26.1 at 500 K; 29.6 at 600 K (all in uPa.s; N2)

Enthalpy of vaporization: 5.57 kJ/mol at -195.79 °C

6.6 dynes/cm at -183 °C; 8.27 dynes/cm at -193 °C; 10.53 dynes/cm at -203 °C

Index of refraction (one atmosphere, 0 °C, wavelength): 1.003012 at 0.4861 um; 1.002998 at 0.5461 um; 1.002990 at 0.5893 un; 1.002982 at 0.6563 um (N2)

Slightly soluble in water.

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

Not Chemically Reactive

These substances undergo no chemical reactions under any known circumstances except those under extreme conditions (liquid nitrogen reacts violently in mixture with magnesium powder when a fuse is lit. Due to formation of magnesium nitride). Otherwise, they are nonflammable, noncombustible and nontoxic. They can asphyxiate.

NITROGEN, REFRIGERATED LIQUID (CRYOGENIC LIQUID) is very unreactive. Nonflammable, noncombustible and nontoxic. Vapors can fill closed spaces and asphyxiate. Contact with water may result in vigorous or violent boiling and extremely rapid vaporization. If the water is hot, there is the possibility that a liquid "superheat" explosion may occur. Pressures may build to dangerous levels if the liquid contacts water in a closed container [Handling Chemicals Safely 1980].

Can react violently with lithium, neodymium, titanium under the proper conditions.

Open vessels which contain organic materials, or which are to be hermetically sealed, should not be cooled in liquid nitrogen, but in a coolant at a higher temperature.

Liquid nitrogen subject to nuclear radiation (high neutron and gamma fluxes) must be kept free of oxygen to prevent explosion occurring in reactor cryostats.

Combines with oxygen and hydrogen on sparking, forming nitric oxide and ammonia, respectively. Combines directly with lithium, and at a red heat with calcium, strontium, and barium to form nitrides. Forms cyanides when heated with carbon in presence of alkalies or barium oxide.

For more Hazardous Reactivities and Incompatibilities (Complete) data for Nitrogen, Elemental (7 total), please visit the HSDB record page.

IDENTIFICATION AND USE: Nitrogen is an odorless, colorless, and tasteless gas that can be condensed into a white liquid. Nitrogen is not registered for current pesticide use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses. It is used in manufacturing of ammonia, nitric acid, nitrates, cyanides, etc; in manufacturing explosives; in filling high-temperature thermometers, incandescent bulbs; to form an inert atmosphere for preservation of materials; as a pharmaceutic aid (air displacement); and for use in dry boxes or glove bags. Liquid nitrogen is used in food-freezing processes; and in the laboratory as a coolant. Nitrogen is used by oil industry to build up great pressures in wells to force crube oil upward, and in hydraulic fracturing. HUMAN EXPOSURE AND TOXICITY: Nitrogen gas is an inert substance and is present in the atmosphere at a level of 78.1%. It does not exhibit a direct toxicological effect and has no toxicological profile. It acts by simple asphyxia. If the level of nitrogen increases, this will lead to a reduction in the level of oxygen to below normal atmospheric levels of 20.8%. Nitrogen has a direct toxic action of its own, affecting brain functions and inducing a stupor or euphoria. Nitrogen induced CNS depression ("rapture of the deep" or "the martini effect") results from a direct toxic effect of high nitrogen pressure on nerve conduction and produces effects similar to alcohol intoxication. Complex reasoning, decision-making ability, motor function, and manual dexterity decrease. Individuals vary in this response widely, but it typically can be noticed among divers at depths exceeding 100 ft (30 m). For example, certain individuals experience no effect at depths of < or = 130 ft, whereas others feel some effect at around 80 ft. Nonetheless, the CNS depressant effect increases with increasing depth so that each additional 50 ft incrementally produces the effect of "another martini". Contact with liquid nitrogen may cause frostbite and severe skin burns. On resurfacing from deep sea diving, decompression sickness can arise from the subsequent release of nitrogen from body tissues. Decompression sickness is attributed to the formation of gas bubbles, mainly nitrogen, in tissues with the rapid release of pressure. ANIMAL STUDIES: Acute nitrogen normobaric hypoxic challenges resulting in an approximate 50% survival, was performed in young adult male and female heterozygous OF1 mice under various environmental conditions. The time required for 50% survival was 20 minutes for a constant pO2 of 42 torr, and 151 minutes when pO2 was progressively lowered by nitrogen flushing from 159 to 16.5 torr. In synchronized animals, survival was significantly (p > 0.001) less when hypoxia was performed during the light phase than during the dark phase. Lowering the ambient temperature from 33.8 to 13.2 °C increased the length of the progressive hypoxia necessary to obtain a 50% survival of the mice and diminished the final pO2 from 35 to 12 torr. Grouping and crowding both decreased the hypoxic survival. Starvation diminished hypoxic resistance of mice, while carbon monoxide inhalation, or sodium cyanide injection had the opposite effect. In all these variations, OF1 females were more resistant than males. Most of these variations can be related to differences in respiratory exchanges, locomotor activity, and aggressiveness, which are dependent upon the various experimental environmental parameters. Another study in mice, found that excitement threshold pressures decrease with increased concentration of nitrogen; coarse tremor onset is delayed in direct proportion to the amount of nitrogen present with the same relative potency in compression at 60 atm/hr as at 1000 atm/hr; and threshold pressure of convulsion from high pressure neurological syndrome increases with increased amount of nitrogen. ECOTOXICITY STUDIES: Nitrogen is an essential nutrient for plant growth and development but is unavailable in its most prevalent form as atmospheric nitrogen. Plants instead depend upon combined, or fixed, forms of nitrogen, such as ammonia and nitrate. Much of this nitrogen is provided to cropping systems in the form of industrially produced nitrogen fertilizers. Use of these fertilizers has led to worldwide, ecological problems, such as the formation of coastal dead zones. Biological nitrogen fixation, on the other hand, offers a natural means of providing nitrogen for plants. It is a critical component of many aquatic, as well as terrestrial ecosystems across our biosphere.

Nitrogen

Nutrient

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

◉ Summary of Use during Lactation

No information is available on the clinical use of liquid nitrogen on the skin during breastfeeding. Because it is a nontoxic gas that is unlikely to appear in breastmilk or be absorbed by the infant, it is considered safe to use during breastfeeding. No special precautions are required.

◉ Effects in Breastfed Infants

Relevant published information was not found as of the revision date.

◉ Effects on Lactation and Breastmilk

The substance can be absorbed into the body by inhalation.

Unconsciousness. Weakness. Suffocation.

Suffocation.

ON CONTACT WITH LIQUID: FROSTBITE.

Pain. Severe deep burns. Further see Skin.

Other Poison - Simple Asphyxiant

Central nervous system (CNS) oxygen toxicity of mixtures of oxygen with inert gas was studied in rats. Male Charles-River-rats with surgically implanted electroencephalograph (EEG) electrodes were exposed to binary mixtures of oxygen with nitrogen or helium having total pressures of 5 to 10 atmospheres absolute (ATA) in a hyperbaric chamber. The oxygen partial pressure in each mixture was 5ATA. CNS toxicity was evaluated by measuring the length of time between obtaining the desired pressure in the chamber until the appearance of electrical discharges in the EEG (latency period). The animals were observed for signs of intoxication. The results for both nitrogen and helium mixtures were the same. The duration of the latency period decreased with increasing inert gas partial pressure, the minimum latency occurring with mixtures containing 3ATA nitrogen or helium. Several rats exposed to mixtures containing 4 or 5ATA nitrogen appeared drowsy, although when the electrical discharges began these rats showed the characteristic signs of epileptic seizures. Duration of the latent period was not correlated with severity of the epileptic seizures. The authors suggest that the risk of CNS oxygen toxicity does not depend just on the partial pressure of oxygen, and that when calculating the oxygen partial pressure in breathing gas mixtures for divers, the partial pressures of the other (inert) gases should be considered.

The contribution of inert gases to the risk of central nervous system (CNS) oxygen toxicity is a matter of controversy. Therefore, diving regulations apply strict rules regarding permissible oxygen pressures (Po(2)). We studied the effects of nitrogen and helium (0, 15, 25, 40, 50, and 60%) and different levels of Po(2) (507, 557, 608, and 658 kPa) on the latency to the first electrical discharge (FED) in the EEG in rats, with repeated measurements in each animal. Latency as a function of the nitrogen pressure was not homogeneous for each rat. The prolongation of latency observed in some rats at certain nitrogen pressures, mostly in the range 100 to 500 kPa, was superimposed on the general trend for a reduction in latency as nitrogen pressure increased. This pattern was an individual trait. In contrast with nitrogen, no prolongation of latency to CNS oxygen toxicity was observed with helium, where an increase in helium pressure caused a reduction in latency. This bimodal response and the variation in the response between rats, together with a possible effect of ambient temperature on metabolic rate, may explain the conflicting findings reported in the literature. The difference between the two inert gases may be related to the difference in the narcotic effect of nitrogen. Proof through further research of a correlation between individual sensitivity to nitrogen narcosis and protection by N(2) against CNS oxygen toxicity in rat may lead to a personal O(2) limit in mixed-gas diving based on the diver sensitivity to N(2) narcosis.

The effects of adenosine-5'-diphosphate (ADP), epinephrine, nd 5-hydroxytryptamine (5HT) on nitrogen microbubble induced platelet aggregation were studied in-vitro. Platelet rich plasma (PRP) obtained from healthy human blood donors was stirred for 30 minutes in the presence of nitrogen microbubbles, 0.5 to 5 micromolar (microM) ADP, 0.1 to 1microM epinephrine, or 0.5 to 10microM 5HT, alone or in combination. The experiments with epinephrine were also performed in the presence or absence of 25microM indomethacin, 10microM acetylsalicylic-acid (ASA), or 1microM (146485). Some of the experiments with 5HT had 12.5microM ketanserin present. The extent of platelet aggregation was determined by measuring changes in platelet density in a cellcounter. A similar experiment was performed in which the PRP was pretreated with nitrogen microbubbles for 5 minutes before the ADP, epinephrine, or 5HT was added. Nitrogen microbubbles alone caused a progressive, irreversible aggregation of platelets. ADP alone caused an immediate platelet aggregation. Microbubbles plus ADP showed an additive, irreversible effect. Epinephrine alone caused a progressive, irreversible decrease in platelet density. Nitrogen microbubbles plus epinephrine showed a strong synergistic effect on platelet aggregation. Indomethacin and ASA partially countered the synergistic effect. 5HT caused a slight decrease in platelet density. 5HT plus nitrogen microbubbles inhibited platelet aggregation. The effect of 5HT was abolished by ketanserin. Microbubble stimulation of PRP before adding ADP, 5HT, and epinephrine made the platelets more responsive to epinephrine only. The authors conclude that epinephrine has a clear synergistic effect on nitrogen microbubble induced platelet aggregation. ...

The effect of oxygen on nitrogen elimination was studied for six healthy nonsmoking males, 22 to 35 years old. Subjects breathed oxygen/argon mixtures having oxygen partial pressures (PO2s) of 0.12, 0.2, 1.0, 2.0, or 2.5 atmospheres (atm) for 125 minutes in a closed circuit system. Respiratory elimination of nitrogen by the subjects was measured using a gas tight rebreathing apparatus. Heart rate, cardiac output, calf blood flow, skin perfusion, blood pressure, and mean arterial pressure were monitored. Breathing 0.12atm oxygen caused a 9.4% increase in nitrogen elimination compared to the normoxic condition, PO2 0.2atm. Breathing pure oxygen, PO2 1.0atm, caused a 3.5% decrease in nitrogen elimination. Breathing mixtures containing 2.0 and 2.5atm oxygen caused 8.9 and 16.9% decreases in nitrogen elimination, respectively. Increasing the PO2 in the breathing mixture caused decreases in heart rate, cardiac output, skin perfusion, and calf blood flow. Systolic blood pressure was not affected. Diastolic blood pressure was decreased by the hypoxic gas mixture, but increased with increasing PO2 in the other mixtures. Mean arterial pressure increased with increasing PO2. The authors conclude that increasing PO2 in breathing mixtures causes a decrease in perfusion dependent nitrogen elimination that is secondary to a vasoconstrictive effect. These results suggest that oxygen breathing during post dive decompression treatment should be done at the lowest possible PO2 that does not induce decompression sickness.

The physiological consequences of anoxia caused by exposure to carbon-monoxide and nitrogen were studied in isolated hearts of rats. Male Sprague-Dawley-rats were anesthetized, and hearts were removed, suspended in saline, cannulated, and perfused in a mixture of 95 percent oxygen/5 percent carbon-dioxide, 95 percent carbon-monoxide/5 percent carbon-dioxide, or 95 percent nitrogen/5 percent carbon-dioxide. All hearts were perfused with oxygen for 30 minutes before switching to test perfusate. Heart function was constantly monitored under the different conditions. The lactic-acid content of perfusate was measured. The glycogen contents of the hearts were determined by a spectrophotometric method. The water content was determined by measuring the difference in wet and dry weights of the heart. Data was analyzed for statistical significance. Heart rate declined rapidly when hearts were subjected to stress in the presence of nitrogen or carbon-monoxide; the decline in heart rate was 64 and 44 percent of control values in the presence of carbon-monoxide and nitrogen, respectively. Lactic-acid concentrations increased significantly after nitrogen and carbon-monoxide exposure. Heart tissue water content did not differ between carbon-monoxide and nitrogen exposed hearts. Heart tissue glycogen content decreased significantly in nitrogen or carbon-monoxide exposed hearts. The authors conclude that nitrogen and carbon-monoxide exert differential effects in physiological and biochemical events in the myocardia.

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. /Simple asphyxiants 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. Anticipate seizures and treat if necessary ... . Use rapid rewarming techniques if frostbite occurs ... . /Simple asphyxiants and related compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or is in severe respiratory distress. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Treat seizures with diazepam or lorazepam ... . /Simple asphyxiants and related compounds/

/HUMAN EXPOSURE STUDIES/ Subjects were exposed to repeated hyperbaric exposures to determine whether humans adapt to the effects of hyperbaric nitrogen so that behavioral impairments are reduced or eliminated with repeated or prolonged exposure. The performance of a single task, standing steadiness, by six men was measured at 5.5 and 1.3 atmospheres absolute during brief hyperbaric exposures on 12 consecutive days. A reduction in the magnitude of the difference between performances at 5.5 and 1.3 atmospheres absolute across days was taken as the measure of behavioral adaptation to nitrogen /SRP: CNS depression/. On each test day, three subjects entered the hyperbaric chamber together and were compressed to 5.5 atmospheres absolute for 30 minutes. Subjects were tested on the standing steadiness test in random order during each test and control session. Standing steadiness was significantly worse at 5.5 atmospheres absolute than at 1.3 atmospheres absolute across all 12 exposures. Changes in standing steadiness also arose from day to day, but these occurred at both the test and control depths. No day/depth interaction was noted which would indicate that the initial performance decrement at 5.5 atmospheres absolute was reduced with repetitive exposures.

/HUMAN EXPOSURE STUDIES/ Simple and complex psychomotor performance were tested among 21 Navy divers under normal conditions and during /nitrogen induced CNS depression/ in simulated dives to 170 ft of sea water. Complex psychomotor performance was impaired significantly during narcosis, while simple psychomotor performance remained essentially normal. Differences between baseline scores for complex psychomotor performance (pre- and post-dive combined) and scores obtained from the 2 combined testing sessions administered during /CNS depression/ were correlated with official Navy records of diving experience and self-reported moods. None of the diving experience measures was associated significantly with these difference scores. The moods of fatigue and happiness were, however, correlated significantly with impairment. Although previous experience with nitrogen /induced CNS depression/ and diving tails do not mediate the performance effects of nitrogen /induced CNS depression/, the complex psychomotor effects of nitrogen narcosis are related to emotional traits.

/SIGNS AND SYMPTOMS/ ...Nitrogen also has a direct toxic action of its own, affecting brain functions and inducing a stupor or euphoria. Nitrogen /induced CNS depression/ ("rapture of the deep" or "the martini effect") results from a direct toxic effect of high nitrogen pressure on nerve conduction and produces effects similar to alcohol intoxication. Complex reasoning, decision-making ability, motor function, and manual dexterity decrease. Individuals vary in this response widely, but it typically can be noticed among divers at depths exceeding 100 ft (30 m). For example, certain individuals experience no effect at depths of < or = 130 ft, whereas others feel some effect at around 80 ft. Nonetheless, the /CNS depressant/ effect increases with increasing depth so that each additional 50 ft incrementally produces the effect of "another martini".

/SIGNS AND SYMPTOMS/ Inhalation: No significant toxic effects except as an asphyxiant, that is, it may threaten life if levels are so high as to reduce oxygen levels below 19%. Since nitrogen is odorless, colorless, and tasteless, there may not be adequate warning of high levels. Symptoms of lack of oxygen may include nausea, drowsiness, blue coloration of skin and lips, unconsciousness, and death. Skin: liquid may cause frostbite and freezing burns. Eyes: liquid may cause frostbite and freezing burns. Ingestion: liquid may cause frostbite and freezing burns.

For more Human Toxicity Excerpts (Complete) data for Nitrogen, Elemental (14 total), please visit the HSDB record page.

/LABORATORY ANIMALS: Acute Exposure/ Nitrogen gas at room temperature injected into anterior chamber of rabbits, replacing part of aqueous humor, ... is nontoxic and is absorbed in 2 or 3 days ...

/LABORATORY ANIMALS: Acute Exposure/ Acute nitrogen normobaric hypoxic challenges /resulting in an approximate/ 50% ... survival, was performed in young adult male and female heterozygous OF1 mice under various environmental conditions. The time required /for/ 50% survival was 20 minutes for a constant pO2 of 42 torr, and 151 minutes when pO2 was progressively lowered by nitrogen flushing from 159 to 16.5 torr. In ... synchronized animals, survival was significantly (p > 0.001) less when hypoxia was performed during the light phase than during the dark phase. Lowering the ambient temperature from 33.8 to 13.2 °C increased the length of the progressive hypoxia necessary to obtain a 50% survival of the mice ... and diminished the final pO2 from 35 to 12 torr. Grouping and crowding both decreased the hypoxic survival ... Starvation diminished hypoxic resistance of mice, while ... carbon monoxide inhalation, or sodium cyanide injection had the opposite effect. In all these variations, OF1 females were more resistant than males. Most of these variations can be related to differences in respiratory exchanges, locomotor activity, and aggressiveness, which are dependent upon the various experimental environmental parameters.

/LABORATORY ANIMALS: Neurotoxicity/ Wistar rat pups were exposed to 99.99%-nitrogen gas for 10 minutes at 4 days of age, and then their behavior and susceptibility to pentylentetrazol (PTZ) induced seizure were investigated at the ages of 28 and 56 days. Neonatal anoxic rats exhibited hyperactivity in the open field examination and motor coordination disturbance in the inclined screen test, hyperirritability to the startle response and high susceptibility to PTZ at the age of 28 days. However, these behavioral changes and high susceptibility to PTZ were improved with development and there were no longer significant difference from controls rats at 56 days of age except the wire maneuver test. These results suggested that neonatal total anoxia could produce transient dysfunction of the developing brain, including increased susceptibility to seizure and behavioral abnormalities.

/LABORATORY ANIMALS: Neurotoxicity/ The effects of change in time pattern of nitrogen on the occurrence of high pressure neurological syndrome on mice is discussed. Excitement threshold pressures decrease with increased concentration of nitrogen; coarse tremor onset is delayed in direct proportion to the amount of nitrogen present with the same relative potency in compression at 60 atm/hr as at 1000 atm/hr; and threshold pressure of convulsion from high pressure neurological syndrome increases with increased amount of nitrogen. A bolus effect similar to, though smaller than with coarse tremors, is seen at a compression rate of 60 atm/hr but is absent at 1000 atm/hr.

For more Non-Human Toxicity Excerpts (Complete) data for Nitrogen, Elemental (7 total), please visit the HSDB record page.

/PLANTS/ The effects of elevated carbon dioxide (CO2) and nitrogen (N) addition on foliar N and phosphorus (P) stoichiometry were investigated in five native tree species (four non-N2 fixers and one N2 fixer) in open-top chambers in southern China from 2005 to 2009. The high foliar N:P ratios induced by high foliar N and low foliar P indicate that plants may be more limited by P than by N. The changes in foliar N:P ratios were largely determined by P dynamics rather than N under both elevated CO2 and N addition. Foliar N:P ratios in the non-N2 fixers showed some negative responses to elevated CO2, while N addition reduced foliar N:P ratios in the N2 fixer. The results suggest that N addition would facilitate the N2 fixer rather than the non-N2 fixers to regulate the stoichiometric balance under elevated CO2.

/PLANTS/ Nitrogen is an essential nutrient for plant growth and development but is unavailable in its most prevalent form as atmospheric nitrogen. Plants instead depend upon combined, or fixed, forms of nitrogen, such as ammonia and nitrate. Much of this nitrogen is provided to cropping systems in the form of industrially produced nitrogen fertilizers. Use of these fertilizers has led to worldwide, ecological problems, such as the formation of coastal dead zones. Biological nitrogen fixation, on the other hand, offers a natural means of providing nitrogen for plants. It is a critical component of many aquatic, as well as terrestrial ecosystems across our biosphere.

/PLANTS/ Biological nitrogen fixation (BNF) is a key ecological process that can restore nitrogen (N) lost in wildfire and shape the pace and pattern of post-fire forest recovery. To date, there is limited information on how climate and soil fertility interact to influence different pathways of BNF in early forest succession. We studied asymbiotic (forest floor and soil) and symbiotic (the shrub Ceanothus integerrimus) BNF rates across six sites in the Klamath National Forest, California, USA. We used combined gradient and experimental phosphorus (P) fertilization studies to explore cross-site variation in BNF rates and then related these rates to abiotic and biotic variables. We estimate that our measured BNF rates 22 years after wildfire (6.1-12.1 kg N /per/ ha /per/ yr) are unlikely to fully replace wildfire N losses. We found that asymbiotic BNF is P limited, although this is not the case for symbiotic BNF in Ceanothus. In contrast, Ceanothus BNF is largely driven by competition from other vegetation: in high-productivity sites with high potential evapotranspiration (Et), shrub biomass is suppressed as tree biomass increases. Because shrub biomass governed cross-site variation in Ceanothus BNF, this competitive interaction led to lower BNF in sites with high productivity and Et. Overall, these results suggest that the effects of nutrients play a larger role in driving asymbiotic than symbiotic fixation across our post-fire sites. However, because symbiotic BNF is 8-90 /times/ greater than asymbiotic BNF, it is interspecific plant competition that governs overall BNF inputs in these forests.

/Nitrogen/ constitutes about 75.5% by weight or 78.06% by vol of atmosphere; found frequently in volcanic or mine gases, gases from springs and gases occluded in minerals and rocks ... fixed or combined nitrogen is present in many mineral deposits.

According to the 2012 TSCA Inventory Update Reporting data, 12 reporting facilities estimate the number of persons reasonably likely to be exposed during the manufacturing, processing, or use of nitrogen, elemental in the United States may be as low as <10 workers and as high as 9999 workers per plant; the data may be greatly underestimated due to confidential business information (CBI) or unknown values(1).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 652,326 workers (322,763 of these were female) were potentially exposed to nitrogen, elemental in the US(1). The NOES Survey does not include farm workers. Occupational exposure to nitrogen, elemental may occur through inhalation and dermal contact with this compound at workplaces where nitrogen, elemental is produced or used(SRC).

... an essential constituent of all living organisms ...

/PLANTS/ The effects of elevated carbon dioxide (CO2) and nitrogen (N) addition on foliar N and phosphorus (P) stoichiometry were investigated in five native tree species (four non-N2 fixers and one N2 fixer) in open-top chambers in southern China from 2005 to 2009. The high foliar N:P ratios induced by high foliar N and low foliar P indicate that plants may be more limited by P than by N. The changes in foliar N:P ratios were largely determined by P dynamics rather than N under both elevated CO2 and N addition. Foliar N:P ratios in the non-N2 fixers showed some negative responses to elevated CO2, while N addition reduced foliar N:P ratios in the N2 fixer. The results suggest that N addition would facilitate the N2 fixer rather than the non-N2 fixers to regulate the stoichiometric balance under elevated CO2.

/PLANTS/ Nitrogen is an essential nutrient for plant growth and development but is unavailable in its most prevalent form as atmospheric nitrogen. Plants instead depend upon combined, or fixed, forms of nitrogen, such as ammonia and nitrate. Much of this nitrogen is provided to cropping systems in the form of industrially produced nitrogen fertilizers. Use of these fertilizers has led to worldwide, ecological problems, such as the formation of coastal dead zones. Biological nitrogen fixation, on the other hand, offers a natural means of providing nitrogen for plants. It is a critical component of many aquatic, as well as terrestrial ecosystems across our biosphere.

/PLANTS/ Biological nitrogen fixation (BNF) is a key ecological process that can restore nitrogen (N) lost in wildfire and shape the pace and pattern of post-fire forest recovery. To date, there is limited information on how climate and soil fertility interact to influence different pathways of BNF in early forest succession. We studied asymbiotic (forest floor and soil) and symbiotic (the shrub Ceanothus integerrimus) BNF rates across six sites in the Klamath National Forest, California, USA. We used combined gradient and experimental phosphorus (P) fertilization studies to explore cross-site variation in BNF rates and then related these rates to abiotic and biotic variables. We estimate that our measured BNF rates 22 years after wildfire (6.1-12.1 kg N /per/ ha /per/ yr) are unlikely to fully replace wildfire N losses. We found that asymbiotic BNF is P limited, although this is not the case for symbiotic BNF in Ceanothus. In contrast, Ceanothus BNF is largely driven by competition from other vegetation: in high-productivity sites with high potential evapotranspiration (Et), shrub biomass is suppressed as tree biomass increases. Because shrub biomass governed cross-site variation in Ceanothus BNF, this competitive interaction led to lower BNF in sites with high productivity and Et. Overall, these results suggest that the effects of nutrients play a larger role in driving asymbiotic than symbiotic fixation across our post-fire sites. However, because symbiotic BNF is 8-90 /times/ greater than asymbiotic BNF, it is interspecific plant competition that governs overall BNF inputs in these forests.

/Nitrogen/ constitutes about 75.5% by weight or 78.06% by vol of atmosphere; found frequently in volcanic or mine gases, gases from springs and gases occluded in minerals and rocks ... fixed or combined nitrogen is present in many mineral deposits.

According to the 2012 TSCA Inventory Update Reporting data, 12 reporting facilities estimate the number of persons reasonably likely to be exposed during the manufacturing, processing, or use of nitrogen, elemental in the United States may be as low as <10 workers and as high as 9999 workers per plant; the data may be greatly underestimated due to confidential business information (CBI) or unknown values(1).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 652,326 workers (322,763 of these were female) were potentially exposed to nitrogen, elemental in the US(1). The NOES Survey does not include farm workers. Occupational exposure to nitrogen, elemental may occur through inhalation and dermal contact with this compound at workplaces where nitrogen, elemental is produced or used(SRC).

... an essential constituent of all living organisms ...

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

/GUIDE 120 GASES - INERT (Including Refrigerated Liquids)/ Fire or Explosion: Non-flammable gases. Containers may explode when heated. Ruptured cylinders may rocket. /Nitrogen, refrigerated liquid (cryogenic liquid)/

/GUIDE 120 GASES - INERT (Including Refrigerated Liquids)/ Health: Vapors may cause dizziness or asphyxiation without warning. Vapors from liquefied gas are initially heavier than air and spread along ground. Contact with gas or liquefied gas may cause burns, severe injury and/or frostbite. /Nitrogen, refrigerated liquid (cryogenic liquid)/

/GUIDE 120 GASES - INERT (Including Refrigerated Liquids)/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area for at least 100 meters (330 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Many gases are heavier than air and will spread along ground and collect in low or confined areas (sewers, basements, tanks). Keep out of low areas. Ventilate closed spaces before entering. /Nitrogen, refrigerated liquid (cryogenic liquid)/

/GUIDE 120 GASES - INERT (Including Refrigerated Liquids)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection. Always wear thermal protective clothing when handling refrigerated/cryogenic liquids or solids. /Nitrogen, refrigerated liquid (cryogenic liquid)/

For more DOT Emergency Guidelines (Complete) data for Nitrogen, Elemental (16 total), please visit the HSDB record page.

UN 1066; Nitrogen, compressed

UN 1977; Nitrogen, refrigerated liquid, cryogenic liquid

IMO 2.2; Nitrogen, compressed; nitrogen, refrigerated liquid

49 045 65; Nitrogen gas, compressed

49 045 65; Nitrogen or nitrogen, compressed

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Non-Flammable Gas

Special insulated cylinder.

UN Hazard Class: 2.2