From Wikipedia, the free encyclopedia
For other uses, see .
Not to be confused with
(formula NO) or
(formula NO
2). The generic term
includes these two but does not include nitrous oxide.
"Laughing gas" redirects here.
For the comic novel by P.G. Wodehouse, see . For other uses, see .
Nitrous oxide, commonly known as laughing gas, nitrous, nitro, or NOS is a
2O. It is an . At room temperature, it is a colourless,
, with a slightly sweet odour and taste. It is used in
effects. It is known as "laughing gas" due to the
effects of inhaling it, a property that has led to its
anaesthetic. It is also used as an
in the launching of
to increase the power output of . At elevated temperatures, nitrous oxide is a powerful oxidizer similar to molecular oxygen.
Nitrous oxide gives rise to
(NO) on reaction with oxygen atoms, and this NO in turn reacts with . As a result, it is the main naturally occurring regulator of
ozone. It is also a major
and . Considered over a 100-year period, it has 298 times more impact per unit mass () than .
It is on the , the most important medications needed in a .
Nitrous oxide can be used as an
motor. This has the advantages over other oxidisers in that it is not only non-toxic, but also, due to its stability at room temperature, easy to store and relatively safe to carry on a flight. As a secondary benefit it can be readily decomposed to form breathing air. Its high density and low storage pressure (when maintained at low temperature) enable it to be highly competitive with stored high-pressure gas systems.
In a 1914 patent, American rocket pioneer
suggested nitrous oxide and gasoline as possible propellants for a liquid-fuelled rocket. Nitrous oxide has been the oxidiser of choice in several
designs (using solid fuel with a liquid or gaseous oxidizer). The combination of nitrous oxide with
fuel has been used by
and others. It is also notably used in
with various plastics as the fuel.
Nitrous oxide can also be used in a . In the presence of a heated , N
2O will decompose exothermically into nitrogen and oxygen, at a temperature of approximately ;°F. Because of the large heat release, the catalytic action rapidly becomes secondary as thermal autodecomposition becomes dominant. In a vacuum thruster, this can provide a monopropellant
(Isp) of as much as 180 s. While noticeably less than the Isp available from
thrusters (monopropellant or
with ), the decreased toxicity makes nitrous oxide an option worth investigating.
Nitrous oxide is said to
somewhere around 600 °C (1,112 °F) at a pressure of 21 atmospheres. It can also easily be ignited using a combination of the two. At 600 psi for example, the required ignition energy is only 6 joules, whereas N
2O at 130 psi a 2500-joule ignition energy input is insufficient.
Specific impulse (Isp) can be improved by blending a hydrocarbon fuel with the nitrous oxide inside the same storage tank, becoming a nitrous oxide fuel blend () monopropellant. This storage mixture does not incur the danger of spontaneous ignition, since N
2O is chemically stable.[] When the nitrous oxide decomposes by a heated catalyst, high temperature oxygen is released and rapidly ignites the hydrocarbon fuel-blend. NOFB monopropellants are capable of I
sp greater than 300 seconds, while avoiding the toxicity associated with .[] The low freezing point of NOFB eases thermal management compared to
and dinitrogen tetroxide—a valuable property for space storable propellants.
Main article:
In vehicle , nitrous oxide (often referred to as just "") allows the engine to burn more fuel by providing more oxygen than air alone, resulting in a more powerful combustion. The gas itself is not flammable at a low pressure/temperature, but it delivers more
than atmospheric air by breaking down at elevated temperatures. Therefore, it is often mixed with another fuel that is easier to deflagrate.
Nitrous oxide is stored as the
and expansion of liquid nitrous oxide in the
causes a large drop in intake charge temperature, resulting in a denser charge, further allowing more air/fuel mixture to enter the cylinder. Nitrous oxide is sometimes injected into (or prior to) the intake manifold, whereas other systems directly inject right before the cylinder (direct port injection) to increase power.
The technique was used during
aircraft with the
system to boost the power output of . Originally meant to provide the Luftwaffe standard aircraft with superior high-altitude performance, technological considerations limited its use to extremely high altitudes. Accordingly, it was only used by specialized planes like high-altitude , , and high-altitude .
One of the major problems of using nitrous oxide in a reciprocating engine is that it can produce enough power to damage or destroy the engine. Very large power increases are possible, and if the mechanical structure of the engine is not properly reinforced, the engine may be severely damaged or destroyed during this kind of operation. It is very important with nitrous oxide augmentation of
to maintain proper
and fuel levels to prevent "pre-ignition", or "detonation" (sometimes referred to as "knock"). Most problems that are associated with nitrous do not come from mechanical failure due to the power increases. Since nitrous allows a much denser charge into the cylinder it dramatically increases cylinder pressures. The increased pressure and temperature can cause problems such as melting the piston or valves. It may also crack or warp the piston or head and cause pre-ignition due to uneven heating.
Automotive-grade liquid nitrous oxide differs slightly from medical-grade nitrous oxide. A small amount of
2) is added to prevent substance abuse. Multiple washes through a base (such as ) can remove this, decreasing the corrosive properties observed when SO
2 is further oxidised during combustion into , making emissions cleaner.[]
The gas is approved for use as a
(also known as E942), specifically as an . Its most common uses in this context are in aerosol
canisters, , and as an inert gas used to displace oxygen, to inhibit bacterial growth, when filling packages of
and other similar snack foods.
The gas is extremely soluble in fatty compounds. In aerosol whipped cream, it is dissolved in the fatty cream until it leaves the can, when it becomes gaseous and thus creates foam. Used in this way, it produces whipped cream four times the volume of the liquid, whereas whipping air into cream only produces twice the volume. If air were used as a propellant, oxygen would accelera nitrous oxide inhibits such degradation. Carbon dioxide cannot be used for whipped cream because it is acidic in water, which would curdle the cream and give it a seltzer-like "sparkling" sensation.
However, the whipped cream produced with nitrous oxide is unstable and will return to a more liquid state within half an hour to one hour. Thus, the method is not suitable for decorating food that will not be immediately served.
Similarly, , which is made from various types of oils combined with
(an ), may use other propellants used in cooking spray include food-grade
Users of nitrous oxide often obtain it from whipped cream dispensers that use nitrous oxide as a propellant (see above section), for recreational use as a euphoria-inducing
drug. It is not harmful in small doses, but risks due to lack of oxygen do exist (see
Further information:
Medical grade N
2O tanks used in .
Nitrous oxide has been used for anaesthesia in
since December 1844, where
made the first 12–15 dental operations with the gas in . Its debut as a generally accepted method, however, came in 1863, when
introduced it more broadly at all the Colton Dental Association clinics, that he founded in
and . The first devices used in dentistry to administer the gas, known as Nitrous Oxide inhalers, were designed in a very simple way with the gas stored and breathed through a breathing bag made of rubber cloth, without a
and , and with no addition of oxygen/air. Today these simple and somewhat unreliable inhalers have been replaced by the more modern , which is an automated machine designed to deliver a precisely dosed and breath-actuated flow of nitrous oxide mixed with oxygen, for the patient to inhale safely. The machine used in dentistry is designed as a simplified version of the larger
used by hospitals, as it doesn't feature the additional
and . The purpose of the machine allows for a simpler design, as it only delivers a mixture of
for the patient to inhale, in order to depress the feeling of pain while keeping the patient in a conscious state.
Relative analgesia machines typically feature a constant-supply , which allow the proportion of nitrous oxide and the combined gas flow rate to be individually adjusted. The gas is administered by dentists through a
inhaler over the nose, which will only release gas when the patient inhales through the nose. Because nitrous oxide is minimally metabolised in humans (with a rate of 0.004%), it retains its potency when exhaled into the room by the patient, and can pose an intoxicating and prolonged exposure hazard to the clinic staff if the room is poorly ventilated. Where nitrous oxide is administered, a continuous-flow fresh-air
or nitrous
is used to prevent a waste-gas buildup.
Hospitals administer nitrous oxide as one of the anaesthetic drugs delivered by . Nitrous oxide is a weak , and so is generally not used alone in general anaesthesia. In general anaesthesia it is used as a carrier gas in a 2:1 ratio with oxygen for more powerful general anaesthetic drugs such as
or . It has a
of 105% and a
The medical grade gas tanks, with the tradename
contain a mixture with 50%, but this will normally be diluted to a lower percentage upon the operational delivery to the patient. Inhalation of nitrous oxide is frequently used to relieve pain associated with , , , and
(includes heart attacks). Its use during labour has been shown to be a safe and effective aid for women wanting to give birth without an epidural. Its use for acute coronary syndrome is of unknown benefit.
In Britain and Canada, Entonox and Nitronox are commonly used by ambulance crews (including unregistered practitioners) as a rapid and highly effective analgesic gas.
Nitrous oxide has been shown to be effective in treating a number of addictions, including alcohol withdrawal.
Nitrous oxide is also gaining interest as a substitute gas for carbon dioxide in . It has been found to be as safe as carbon dioxide with better pain relief.
Food grade N
(above) and cracker (below)—can be used for recreational purposes
Nitrous oxide can cause , , , , , and some sound distortion. Research has also found that it increases
and . Inhalation of nitrous oxide for recreational use, with the purpose of causing euphoria and/or slight hallucinations, began as a phenomenon for the British upper class in 1799, known as "laughing gas parties". Until at least 1863, a low availability of equipment to produce the gas, combined with a low usage of the gas for medical purposes, meant it was a relatively rare phenomenon that mainly happened among students at medical universities. When equipment became more widely available for dentistry and hospitals, most countries also restricted the legal access to buy pure nitrous oxide
to those sectors. Despite only medical staff and dentists today being legally allowed to buy the pure gas, a
report from 1972 found that the use of the gas for recreational purpose was [then] still taking place, based upon reports of its use in
1972, and a survey made by Dr. Edward J. Lynn of its non-medical use in
It was not uncommon [in the interviews] to hear from individuals who had been to parties where a professional (doctor, nurse, scientist, inhalation therapist, researcher) had provided nitrous oxide. There also were those who work in restaurants who used the N
2O stored in tanks for the preparation of whip cream. Reports were received from people who used the gas contained in aerosol cans both of food and non-food products. At a recent rock festival nitrous oxide was widely sold for 25 cents a balloon. Contact was made with a "mystical-religious" group that used the gas to accelerate arriving at their
state of choice. Although a few, more sophisticated users employed nitrous oxide-oxygen mixes with elaborate equipment, most users used balloons or plastic bags. They either held a breath of N
2O or rebreathed the gas. There were no adverse effects reported in the more than one hundred individuals surveyed.
In Australia, nitrous oxide bulbs are known as , possibly derived from the sound distortion perceived by consumers.
In the United Kingdom, nitrous oxide is used by almost half a million young people at nightspots, festivals and parties.
The pharmacological
2O in medicine is not fully known. However, it has been shown to directly modulate a broad range of , and this likely plays a major role in many of its effects. It moderately blocks
and -containing , weakly inhibits , , , and , and slightly potentiates
and . It has also been shown to activate . While N
2O affects quite a few ion channels, its anaesthetic, , and
effects are likely caused predominantly or fully via inhibition of NMDAR-mediated currents. In addition to its effects on ion channels, N
2O may act to imitate
(NO) in the central nervous system, and this may be related to its
properties.
In behavioural tests of , a low dose of N
2O is an effective , and this anti-anxiety effect is associated with enhanced activity of GABAA receptors, as it is partially reversed by
. Mirroring this, animals which have developed tolerance to the anxiolytic effects of
are partially tolerant to N
2O. Indeed, in humans given 30% N
2O, benzodiazepine receptor antagonists reduced the subjective reports of feeling "high", but did not alter
performance, in human clinical studies.
The analgesic effects of N
2O are linked to the interaction between the
system and the descending
system. When animals are given
chronically they develop tolerance to its pain-killing effects, and this also renders the animals tolerant to the analgesic effects of N
2O. Administration of
which bind and block the activity of some endogenous opioids (not ) also block the antinociceptive effects of N
2O. Drugs which inhibit the breakdown of endogenous opioids also potentiate the antinociceptive effects of N
2O. Several experiments have shown that opioid receptor antagonists applied directly to the brain block the antinociceptive effects of N
2O, but these drugs have no effect when injected into the .
Conversely,
antagonists block the pain reducing effects of N
2O when given directly to the spinal cord, but not when applied directly to the brain. Indeed,
knockout mice or animals depleted in
are nearly completely resistant to the antinociceptive effects of N
2O. Apparently N
2O-induced release of endogenous opioids causes disinhibition of
noradrenergic neurons, which release
into the spinal cord and inhibit pain signalling. Exactly how N
2O causes the release of endogenous opioid peptides is still uncertain.
In rats, N
2O stimulates the
via inducing
release and activating
and , presumably through
localised in the system. This action has been implicated in its euphoric effects, and notably, appears to augment its analgesic properties as well.
However, it is remarkable that in mice, N
2O blocks -induced carrier-mediated dopamine release in the nucleus accumbens and , abolishes the
and , and does not produce reinforcing (or aversive) effects of its own. Studies on CPP of N
2O in rats is mixed, consisting of reinforcement, aversion, and no change. In contrast, it is a positive reinforcer in squirrel monkeys, and is well known as a
in humans. These discrepancies in response to N
2O may reflect species variation or methodological differences. In human clinical studies, N
2O was found to produce mixed responses similarly to rats, reflecting high subjective individual variability.
Like other , N
2O was suggested to produce
in the form of
in rodents upon prolonged (several hour) exposure. However, new research has arisen suggesting that Olney's lesions do not occur in humans, and similar drugs like
are now believed not to be acutely neurotoxic. It has been argued that, because N
2O has a very short duration under normal circumstances, it is less likely to be neurotoxic than other NMDA antagonists. Indeed, in rodents, short-term exposure results in only mild injury that is rapidly reversible, and permanent neuronal death only occurs after constant and sustained exposure. Nitrous oxide may also cause neurotoxicity after extended exposure because of . This is especially true of non-medical formulations such as
(also known as "whippets"), which are not necessarily mixed with oxygen.
Additionally, nitrous oxide depletes
levels. This can cause serious neurotoxicity with even acute use if the user has preexisting .
Nitrous oxide is also , inhibiting .
The major safety hazards of nitrous oxide come from the fact that it is a compressed liquefied gas, an asphyxiation risk, and a
. Exposure to nitrous oxide causes short-term decreases in mental performance, audiovisual ability, and manual dexterity. Long-term exposure can cause
deficiency, numbness, reproductive side effects (in pregnant females), and other problems (see ).
recommends that workers' exposure to nitrous oxide should be controlled during the administration of anaesthetic gas in medical, dental, and veterinary operators.
At room temperature (20 °C) the saturated vapour pressure is 58.5 bar, rising up to 72.45 bar at 36.4 °C (97.5 °F)—the . The pressure curve is thus unusually sensitive to temperature. Liquid nitrous oxide acts as a go liquid mixtures may form shock sensitive explosives.[]
As with many strong oxidisers, contamination of parts with fuels have been implicated in rocketry accidents, where small quantities of nitrous/fuel mixtures explode due to "water hammer"-like effects (sometimes called "dieseling"—heating due to
compression of gases can reach decomposition temperatures). Some common building materials such as stainless steel and aluminium can act as fuels with strong oxidisers such as nitrous oxide, as can contaminants, which can ignite due to adiabatic compression.
There have also been accidents where nitrous oxide decomposition in plumbing has led to the explosion of large tanks.
Main article:
Nitrous oxide inactivates the cobalamin form of
by oxidation. Symptoms of , including , , and , can occur within days or weeks of exposure to nitrous oxide anaesthesia in people with subclinical vitamin B12 deficiency. Symptoms are treated with high doses of vitamin B12, but recovery can be slow and incomplete. People with normal vitamin B12 levels have stores to make the effects of nitrous oxide insignificant, unless exposure is repeated and prolonged (nitrous oxide abuse). Vitamin B12 levels should be checked in people with risk factors for vitamin B12 deficiency prior to using nitrous oxide anaesthesia.
A study of workers and several experimental animal studies indicate that adverse reproductive effects for pregnant females may also result from chronic exposure to nitrous oxide.
is an important enzyme which limits the emission of the gas to the atmosphere.
2O is a greenhouse gas with a large global warming potential (GWP). When compared to carbon dioxide (CO
2O has 298 times the ability per molecule of gas to trap heat in the atmosphere. N
2O is produced naturally in the soil during the microbial processes of
The United States of America signed and ratified the United Nations Framework Convention on Climate Change () in 1992, agreeing to inventory and assess the various sources of greenhouse gases that contribute to climate change. The agreement requires parties to "develop, periodically update, publish and make available... national inventories of anthropogenic emissions by sources and removals by sinks of all greenhouse gases not controlled by the , using comparable methodologies...". In response to this agreement, the U.S. is obligated to inventory
emissions by sources and sinks, of which agriculture is a key contributor. In 2008, agriculture contributed 6.1% of the total U.S. greenhouse gas emissions and cropland contributed nearly 69% of total direct nitrous oxide (N
2O) emissions. Additionally, estimated emissions from agricultural soils were 6% higher in 2008 than 1990.
According to 2006 data from the , industrial sources make up only about 20% of all
sources, and include the production of , and the burning of fossil fuel in internal combustion engines. Human activity is thought to account for 30%; tropical soils and oceanic release account for 70%. However, a 2008 study by Nobel Laureate
suggests that the amount of nitrous oxide release attributable to agricultural nitrate fertilizers has been seriously underestimated, most of which would presumably come under soil and oceanic release in the Environmental Protection Agency data. Atmospheric levels have risen by more than 15% since 1750. Nitrous oxide also causes . A new study suggests that N2O emission currently is the single most important ozone-depleting substance (ODS) emission and is expected to remain the largest throughout the 21st century.
Nitrous oxide production
Nitrous oxide is most commonly prepared by careful heating of , which decomposes into nitrous oxide and water vapour. The addition of various
favours formation of a purer gas at slightly lower temperatures. One of the earliest commercial producers was
3 (s) → 2 H
2O (g) + N
This reaction occurs between 170 and 240 °C (338 and 464 °F), temperatures where ammonium nitrate is a moderately sensitive
and a very powerful . Above 240 °C (464 °F) the
may accelerate to the point of , so the mixture must be cooled to avoid such a disaster. Superheated steam is used to reach reaction temperature in some
production plants.
Downstream, the hot, corrosive mixture of gases must be cooled to condense the steam, and filtered to remove higher oxides of nitrogen. Ammonium nitrate smoke, as an extremely persistent , will also have to be removed. The cleanup is often done in a train namely base, acid and base again. Any significant amounts of nitric oxide (NO) may not necessarily be absorbed directly by the base (sodium hydroxide) washes.
The nitric oxide impurity is sometimes
out with , reduced with iron metal, or oxidised and absorbed in base as a higher oxide. The first base wash may (or may not) react out much of the ammonium nitrate smoke. However, this reaction generates ammonia gas, which may have to be absorbed in the acid wash.
T one of the two reactants used in nylon manufacture, produces nitrogen oxides including nitric oxides This might become a major commercial source, but will require the removal of higher oxides of nitrogen and organic impurities. Currently much of the gas is decomposed before release for environmental protection.
Heating a mixture of sodium nitrate and ammonium sulphate.
3 + (NH4)2SO4 → Na2SO4 + 2N
The reaction of urea, nitric acid and sulfuric acid
2 (NH2)2CO + 2 HNO
2 + (NH4)2SO4 + 2H
Direct oxidation of ammonia with a - catalyst: cf. .
with . If the nitrite is added to the hydroxylamine solution, the only remaining by-product is salt water. However, if the hydroxylamine solution is added to the nitrite solution (nitrite is in excess), then toxic higher oxides of nitrogen are also formed.
3OH+Cl- + NaNO
2O + NaCl + 2 H
Reacting HNO
3 with SnCl
2 and HCl:
3 + 8 HCl + 4 SnCl
2O + 4 SnCl
decomposes to N2O and water with a
of 16 days at 25 °C at pH 1–3.
H2N2O2→ H2O + N2O
Of the entire
2O emission (5.7 teragrams N
2O-N per year), agricultural soils provide 3.5 teragrams N
2O–N per year. Nitrous oxide is produced naturally in the soil during the microbial processes of , , nitrifier denitrification and others:
aerobic autotrophic nitrification, the stepwise oxidation of ammonia (NH
3) to nitrite (NO-
2) and to nitrate (NO-
3) (e.g., Kowalchuk and Stephen, 2001),
anaerobic heterotrophic denitrification, the stepwise reduction of NO-
2, nitric oxide (NO), N
2O and ultimately N
2, where facultative anaerobe bacteria use NO-
3 as an electron acceptor in the respiration of organic material in the condition of insufficient oxygen (O
2) (e.g. Knowles, 1982), and
nitrifier denitrification, which is carried out by autotrophic NH
3-oxidizing bacteria and the pathway whereby ammonia (NH
3) is oxidised to nitrite (NO-
2), followed by the reduction of NO-
2 to nitric oxide (NO), N
2O and molecular nitrogen (N
2) (e.g., Webster and Hopkins, 1996; Wrage et al., 2001).
2O production mechanisms include heterotrophic nitrification (Robertson and Kuenen, 1990), aerobic denitrification by the same heterotrophic nitrifiers (Robertson and Kuenen, 1990), fungal denitrification (Laughlin and Stevens, 2002), and non-biological process chemodenitrification (e.g. Chalk and Smith, 1983; Van Cleemput and Baert, 1984; Martikainen and De Boer, 1993; Daum and Schenk, 1998; M?rkved et al., 2007).
2O emissions are reported to be controlled by soil chemical and physical properties such as the availability of mineral N, soil pH, organic matter availability, and soil type, and climate related soil properties such as soil temperature and soil water content (e.g., Mosier, 1994; Bouwman, 1996; Beauchamp, 1997; Yamulki et al. 1997; Dobbie and Smith, 2003; Smith et al. 2003; Dalal et al. 2003).
Nitrous oxide is a colourless, non-toxic gas with a faint, sweet odour.
Nitrous oxide supports combustion by releasing the
oxygen radical,[Name?] thus it can relight a glowing .
2O is inert at room temperature and has few reactions. At elevated temperatures, its reactivity increases. For example, nitrous oxide reacts with NaNH
2 at 460 K (187 °C) to give NaN
3 + NaOH + NH
The above reaction is the route adopted by the commercial chemical industry to produce azide salts, which are used as detonators.
Greenhouse gas trends.
Nitrous oxide is emitted by
in soils and oceans, and is thus a part of Earth's atmosphere. Agriculture is the main source of human-produced nitrous oxide: cultivating soil, the use of , and animal waste handling can all stimulate naturally occurring bacteria to produce more nitrous oxide. The livestock sector (primarily cows, chickens, and pigs) produces 65% of human-related nitrous oxide. Industrial sources make up only about 20% of all anthropogenic sources, and include the production of , and the burning of fossil fuel in internal combustion engines. Human activity is thought to account for 30%; tropical soils and oceanic release account for 70%.
Nitrous oxide reacts with
in the . Nitrous oxide is the main naturally occurring regulator of stratospheric ozone. Nitrous oxide is a major . Considered over a 100-year period, it has 298 times more impact per unit weight than . Thus, despite its low concentration, nitrous oxide is the fourth largest contributor to these greenhouse gases. It ranks behind water vapour, carbon dioxide, and methane. Control of nitrous oxide is part of efforts to curb greenhouse gas emissions.
The gas was first synthesised by English
and chemist
in 1772, who called it phlogisticated nitrous air (see ). Priestley published his discovery in the book Experiments and Observations on Different Kinds of Air (1775), where he described how to produce the preparation of "nitrous air diminished", by heating iron filings dampened with .
The first important use of nitrous oxide was made possible by
and , who worked together to publish the book Considerations on the Medical Use and on the Production of Factitious Airs (1794). This book was important for two reasons. First, James Watt had invented a novel machine to produce "Factitious Airs" (i.e. nitrous oxide) and a novel "breathing apparatus" to inhale the gas. Second, the book also presented the new medical theories by Thomas Beddoes, that
and other lung diseases could be treated by inhalation of "Factitious Airs".
The machine to produce "Factitious Airs" had three parts: A furnace to burn the needed material, a vessel with water where the produced gas passed through in a spiral pipe (for impurities to be "washed off"), and finally the gas cylinder with a gasometer where the gas produced, "air", could be tapped into portable air bags (made of airtight oily silk). The breathing apparatus consisted of one of the portable air bags connected with a tube to a mouthpiece. With this new equipment being engineered and produced by 1794, the way was paved for ,[] which began when
in 1798 established the " for Relieving Diseases by Medical Airs" in . In the basement of the building, a large-scale machine was producing the gases under the supervision of a young , who was encouraged to experiment with new gases for patients to inhale. The first important work of Davy was examination of the nitrous oxide, and the publication of his results in the book: Researches, Chemical and Philosophical (1800). In that publication, Davy notes the analgesic effect of nitrous oxide at page 465 and its potential to be used for surgical operations at page 556.
Despite Davy's discovery that inhalation of nitrous oxide could relieve a conscious person from pain, another 44 years elapsed before doctors attempted to use it for . The use of nitrous oxide as a
at "laughing gas parties", primarily arranged for the , became an immediate success beginning in 1799. While the effects of the gas generally make the user appear stuporous, dreamy and sedated, some people also "get the giggles" in a state of euphoria, and frequently erupt in laughter.
Further information:
The first time nitrous oxide was used as an
drug in the treatment of a patient was when dentist , with assistance by
and , demonstrated insensitivity to pain from a
on 11 December 1844. In the following weeks, Wells treated the first 12–15 patients with nitrous oxide in , and according to his own record only failed in two cases. In spite of these convincing results being reported by Wells to the medical society in
already in December 1844, this new method was not immediately adopted by other dentists. The reason for this was most likely that Wells, in January 1845 at his first public demonstration to the medical faculty in Boston, had been partly unsuccessful, leaving his colleagues doubtful regarding its efficacy and safety. The method did not come into general use until 1863, when
successfully started to use it in all his "Colton Dental Association" clinics, that he had just established in
and . Over the following three years, Colton and his associates successfully administered nitrous oxide to more than 25,000 patients. Today, nitrous oxide is used in dentistry as an , as an adjunct to .
However, nitrous oxide was not found to be a strong enough anaesthetic for use in major surgery in hospital settings. Being a stronger and more potent anaesthetic,
was instead demonstrated and accepted for use in October 1846, along with
in 1847. When
invented the "gas-ether inhaler" in 1876, it however became a common practice at hospitals to initiate all anaesthetic treatments with a mild flow of nitrous oxide, and then gradually increase the
with the stronger ether/chloroform. Clover's gas-ether inhaler was designed to supply the patient with nitrous oxide and ether at the same time, with the exact mixture being controlled by the operator of the device. It remained in use by many hospitals until the 1930s. Although hospitals today are using a more advanced , these machines still use the same principle launched with Clover's gas-ether inhaler, to initiate the anaesthesia with nitrous oxide, before the administration of a more powerful anaesthetic.
In the , possession of nitrous oxide is legal under federal law and is not subject to
purview. It is, however, regulated by the
under the Food Drug and Cosmetics A prosecution is possible under its "misbranding" clauses, prohibiting the sale or distribution of nitrous oxide for the purpose of .
Many states have laws regulating the possession, sale, and distribution of nitrous oxide. Such laws usually ban distribution to minors or limit the amount of nitrous oxide that may be sold without special license.[] For example, in the state of California, possession for recreational use is prohibited and qualifies as a misdemeanour.
has warned that nitrous oxide is a prescription medicine, and its sale or possession without a prescription is an offence under the Medicines Act. This statement would seemingly prohibit all non-medicinal uses of the chemical, though it is implied that only recreational use will be legally targeted.
In , for general anaesthesia purposes, nitrous oxide is available as Nitrous Oxide IP. India's gas cylinder rules (1985) permit the transfer of gas from one cylinder to another for breathing purposes. This law benefits remote hospitals, which would otherwise suffer as a result of India's geographic immensity. Nitrous Oxide IP is transferred from bulk cylinders (17,000 litres [600 cu ft] capacity gas) to smaller pin-indexed valve cylinders (1,800 litres [64 cu ft] of gas), which are then connected to the yoke assembly of . Because India's Food & Drug Authority (FDA-India) rules state that transferring a drug from one container to another (refilling) is equivalent to manufacturing, anyone found doing so must possess a drug manufacturing license.
Tarendash, Albert S. (2001).
(3rd ed.). Barron's Educational Series. p. 44.  .
Disambiguation page []
(PDF). US EPA. Page 164 (document header listing) 2014.
(PDF). World Health Organization. October 2013. p. 6 2014.
Berger, Bruno (5 October 2007).
(PDF). Swiss Propulsion Laboratory. pp. 1–2. ...Self pressurizing (Vapor pressure at 20°C is ~50.1 bar...Nontoxic, low reactivity -& rel. safe handling (General safe ???)...Additional energy from decomposition (as a monopropellant: ISP of 170 s)...Specific impulse doesn’t change much with O/F...[page 2] N2O is a monopropellant (as H2O2 or Hydrazine...)
Goddard, R. H. (1914) "Rocket apparatus"
Munke, Konrad (2 July 2001) , Report at CGA Seminar "Safety and Reliability of Industrial Gases, Equipment and Facilities", 15–17 October 2001, St. Louis, Missouri
(PDF). Scaled Composites. 17 June . For example, N2O flowing at 130 psi in an epoxy composite pipe would not react even with a 2500 J ignition energy input. However, at 600 psi, the required ignition energy was only 6 J.
. Pratt & Whitney Aircraft.
. Patentdocs 2009. Recent experimentally measured engine Isp values exceed 300 s
. FireStar Engineering 2009.[]
Cline, Allen W. (January 2000) . CONTACT! Magazine
. Holley 2013.
Sneader W (2005). . (Part 1: Legacy of the past, chapter 8: systematic medicine, pp. 74–87) (John Wiley and Sons).   2010.
Miller AH (1941). . Anesthesiology journal 2 (4): 398–409.[]
Copeland, Claudia. . Pregnancy.org.
O'Connor RE; Brady W; Brooks SC; Diercks, D.; Egan, J.; Ghaemmaghami, C.; Menon, V.; O'Neil, B. J. et al. (2010). "Part 10: acute coronary syndromes: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care". Circulation 122 (18 Suppl 3): S787–817. :.  .
Gillman, M. A.; Lichtigfeld, F. J. (2004). "Enlarged double-blind randomised trial of benzodiazepines against psychotropic analgesic nitrous oxide for alcohol withdrawal". Addictive Behaviors 29 (6): . :.  . 
Rammohan A, Manimaran AB, Manohar RR, Naidu RM; M M Naidu (2011). "Nitrous oxide for pneumoperitoneum: no laughing matter this! A prospective single blind case controlled study". Int J Surg. 9 (2): 173–6. :.  .
Rammohan, A.; Manimaran, A. B.; Manohar, R. R.; Naidu, R. M. (2011). "Nitrous oxide for pneumoperitoneum: No laughing matter this! A prospective single blind case controlled study". International Journal of Surgery 9 (2): 173–176. :.  .
Giannini, A. J. (1991). Miller, N. S., ed. . New York: Marcel Dekker. p. 396.  .
Whalley MG, Brooks GB; Brooks (2009). "Enhancement of suggestibility and imaginative ability with nitrous oxide". Psychopharmacology (Berl). 203 (4): 745–52. :.  .
Brecher EM (1972). . Consumer Reports Magazine 2013.
Lynn, Edward J.; Walter, Richard G.; Harris, Lance A.; Dendy, R James, Mary (1972).
(PDF). Journal of Psychoactive Drugs (Journal of Psychedelic Drugs) 5: 1. :.
. The Guardian. 9 August .
Yamakura T, Harris RA; Harris (2000). . Anesthesiology 93 (4): . :.  .
Mennerick S, Jevtovic-Todorovic V, Todorovic SM, Shen W, Olney JW, Zorumski CF; Jevtovic-T T S O Zorumski (1998). "Effect of nitrous oxide on excitatory and inhibitory synaptic transmission in hippocampal cultures". Journal of Neuroscience 18 (23): 9716–26.  .
Gruss M, Bushell TJ, Bright DP, Lieb WR, Mathie A, Franks NP; B B L M Franks (2004). "Two-pore-domain K+ channels are a novel target for the anesthetic gases xenon, nitrous oxide, and cyclopropane". Molecular Pharmacology 65 (2): 443–52. :.  .
Emmanouil DE, Quock RM; Quock (2007). . Anesthesia Progress 54 (1): 9–18. :.  .  .
Emmanouil, D. E., Johnson, C. H. & Quock, R. M.; J Quock (1994). "Nitrous oxide anxiolytic effect in mice in the elevated plus maze: mediation by benzodiazepine receptors". Psychopharmacology 115 (1–2): 167–72. :.  .
Zacny, J.P., Yajnik, S., Coalson, D., Lichtor, J.L., Apfelbaum, J.L., Rupani, G., Young, C., Thapar, P. & Klafta, J.; Y C L A R Y T Klafta (1995). "Flumazenil may attenuate some subjective effects of nitrous oxide in humans: a preliminary report". Pharmacology Biochemistry and Behavior 51 (4): 815–9. :.  .
Berkowitz, B. A., Finck, A. D., Hynes, M. D. & Ngai, S. H.; F H Ngai (1979). "Tolerance to nitrous oxide analgesia in rats and mice". Anesthesiology 51 (4): 309–12. :.  .
Branda, E. M., Ramza, J. T., Cahill, F. J., Tseng, L. F. & Quock, R. M.; R C T Quock (2000). "Role of brain dynorphin in nitrous oxide antinociception in mice". Pharmacology Biochemistry and Behavior 65 (2): 217–21. :.
Guo, T. Z., Davies, M. F., Kingery, W. S., Patterson, A. J., Limbird, L. E. & Maze, M.; D K P L Maze (1999). "Nitrous oxide produces antinociceptive response via alpha2B and/or alpha2C adrenoceptor subtypes in mice". Anesthesiology 90 (2): 470–6. :.  .
Sawamura, S., Kingery, W. S., Davies, M. F., Agashe, G. S., Clark, J. D., Koblika, B. K., Hashimoto, T. & Maze, M.; K D A C K H Maze (2000). "Antinociceptive action of nitrous oxide is mediated by stimulation of noradrenergic neurons in the brainstem and activation of [alpha]2B adrenoceptors". J. Neurosci. 20 (24): 9242–51.  .
Maze M, Fujinaga M; Fujinaga (2000). "Recent advances in understanding the actions and toxicity of nitrous oxide". Anaesthesia 55 (4): 311–4. :.  .
Sakamoto S; Nakao S; Masuzawa M; Inada, T Maze, M Franks, Nicholas P.; Shingu, Koh (2006). "The differential effects of nitrous oxide and xenon on extracellular dopamine levels in the rat nucleus accumbens: a microdialysis study". Anesthesia and Analgesia 103 (6): 1459–63. :.  .
Benturquia N, Le Marec T, Scherrmann JM, Noble F; Le M S Noble (2008). "Effects of nitrous oxide on dopamine release in the rat nucleus accumbens and expectation of reward". Neuroscience 155 (2): 341–4. :.  .
Lichtigfeld FJ, Gillman MA; Gillman (1996). "Role of dopamine mesolimbic system in opioid action of psychotropic analgesic nitrous oxide in alcohol and drug withdrawal". Clinical Neuropharmacology 19 (3): 246–51. :.  .
Koyanagi S, Himukashi S, Mukaida K, Shichino T, Fukuda K; H M S Fukuda (2008). "Dopamine D2-like receptor in the nucleus accumbens is involved in the antinociceptive effect of nitrous oxide". Anesthesia and Analgesia 106 (6): 1904–9. :.  .
David HN, Ansseau M, Lemaire M, Abraini JH; A L Abraini (2006). "Nitrous oxide and xenon prevent amphetamine-induced carrier-mediated dopamine release in a memantine-like fashion and protect against behavioral sensitization". Biological Psychiatry 60 (1): 49–57. :.  .
Benturquia N; Le Guen S; Canestrelli C; Lagente, V.; Apiou, G.; Roques, B.P.; Noble, F. (2007). "Specific blockade of morphine- and cocaine-induced reinforcing effects in conditioned place preference by nitrous oxide in mice". Neuroscience 149 (3): 477–86. :.  .
Ramsay DS, Watson CH, Leroux BG, Prall CW, Kaiyala KJ; W L P Kaiyala (2003). "Conditioned place aversion and self-administration of nitrous oxide in rats". Pharmacology, Biochemistry, and Behavior 74 (3): 623–33. :.  .
Wood RW, Grubman J, Weiss B; G Weiss (1977). "Nitrous oxide self-administration by the squirrel monkey". The Journal of Pharmacology and Experimental Therapeutics 202 (3): 491–9.  .
Zacny JP, Galinkin JL; Galinkin (1999). . Anesthesiology 90 (1): 269–88. :.  .
Dohrn CS, Lichtor JL, Coalson DW, Uitvlugt A, de Wit H, Zacny JP; L C U De W Zacny (1993). "Reinforcing effects of extended inhalation of nitrous oxide in humans". Drug and Alcohol Dependence 31 (3): 265–80. :.  .
Walker DJ, Zacny JP; Zacny (2001). "Within- and between-subject variability in the reinforcing and subjective effects of nitrous oxide in healthy volunteers". Drug and Alcohol Dependence 64 (1): 85–96. :.  .
Jevtovic-Todorovic V, Beals J, Benshoff N, Olney JW; B B Olney (2003). "Prolonged exposure to inhalational anesthetic nitrous oxide kills neurons in adult rat brain". Neuroscience 122 (3): 609–16. :.  .
Nakao S; Nagata A; Masuzawa M; Miyamoto, E; Yamada, M; Nishizawa, N; Shingu, K (2003). "NMDA receptor antagonist neurotoxicity and psychotomimetic activity". Masui. the Japanese Journal of Anesthesiology (in Japanese) 52 (6): 594–602.  .
Jevtovic-Todorovic V, Benshoff N, Olney JW; B Olney (2000). . British Journal of Pharmacology 130 (7): 1692–8. :.  .  .
Jevtovic-Todorovic V, Carter LB; Carter (2005). "The anesthetics nitrous oxide and ketamine are more neurotoxic to old than to young rat brain". Neurobiology of Aging 26 (6): 947–56. :.  .
Slikker, W.; Zou, X.; Hotchkiss, C. E.; Divine, R. L.; Sadovova, N.; Twaddle, N. C.; Doerge, D. R.; Scallet, A. C.; Patterson, T. A.; Hanig, J. P.; Paule, M. G.; Wang, C. (2007). "Ketamine-Induced Neuronal Cell Death in the Perinatal Rhesus Monkey". Toxicological Sciences 98 (1): 145–158. :.  .
Sun, L Qi Li; Qing Li; Yuzhe Z Dexiang L Hong J Fang P David T. Yew (November 2012). "Chronic ketamine exposure induces permanent impairment of brain functions in adolescent cynomolgus monkeys". Addiction Biology 19 (2): 185–94. :.  .
Abraini JH, David HN, Lemaire M; D Lemaire (2005). "Potentially neuroprotective and therapeutic properties of nitrous oxide and xenon". Annals of the New York Academy of Sciences 1053: 289–300. :. :.  .
De Vasconcellos, K; Sneyd, J. R. (2013). "Nitrous oxide: Are we still in equipoise? A qualitative review of current controversies". British Journal of Anaesthesia 111 (6): 877–85. :.  . 
Flippo, T. S.; Holder Jr, W. D. (1993). "Neurologic Degeneration Associated with Nitrous Oxide Anesthesia in Patients with Vitamin B12 Deficiency". Archives of Surgery 128 (12): 1391–5. :.  .
. Cincinnati, OH: U.S. Department of Health, Education, and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 77B140.
. Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-100
. Air Liquide Gas Encyclopedia.
(PDF). . Archived from
(PDF) on 1 September 2006.
Giannini, A.J. (1999). Drug Abuse. Los Angeles: Health Information Press.  .
Conrad, Marcel (4 October 2006).
Rowland, A.S.; Baird, D.D.; Weinberg, C.R.; Shore, D.L.; Shy, C.M.; Wilcox, A.J. (1992). "Reduced fertility among women employed as dental assistants exposed to high levels of nitrous oxide". The New England Journal of Medicine 327 (14): 993–7. :.  .
Vieira, E.; Cleaton-Jones, P.; Austin, J.C.; Moyes, D.G.; Shaw, R. (1980). "Effects of low concentrations of nitrous oxide on rat fetuses". Anesthesia and Analgesia 59 (3): 175–7. :.  .
Vieira, E. (1979). "Effect of the chronic administration of nitrous oxide 0.5% to gravid rats". British journal of anaesthesia 51 (4): 283–7. :.  .
Vieira, E; Cleaton-Jones, P; Moyes, D. (1983). "Effects of low intermittent concentrations of nitrous oxide on the developing rat fetus". British journal of anaesthesia 55 (1): 67–9. :.  .
Schneider, Lisa K.; Wüst, A Pomowski, A Zhang, L Einsle, Oliver (2014). "Chapter 8. No Laughing Matter: The Unmaking of the Greenhouse Gas Dinitrogen Monoxide by Nitrous Oxide Reductase". In Peter M.H. Kroneck and Martha E. Sosa Torres. The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment. Metal Ions in Life Sciences 14. Springer. pp. 177–210. :.
(PDF). Environmental Protection Agency. 15 November .
Sloss, Leslie L. (1992). . William Andrew. p. 6.  .
. Epa.gov 2011.
. Unfccc.int. 31 December .[]
. U.S. Environmental Protection Agency. .
Crutzen, P. J.; Mosier, A. R.; Smith, K. A.; Winiwarter, W. (2008). "N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels". Atmospheric Chemistry and Physics 8 (2): 389. :.
Ravishankara, A. R.; Daniel, J. S.; Portmann, R. W. (2009). "Nitrous Oxide (N2O): The Dominant Ozone-Depleting Substance Emitted in the 21st Century". Science 326 (5949): 123–5. :. :.  .
Grossman, Lisa (28 August 2009). . NewScientist.
Holleman, A. F.; Wiberg, E. (2001). Inorganic Chemistry. San Diego: Academic Press.  .
. Washington Post. 3 February . Cousin of Famous Poet and Noted as a Scientist. Inventor of the Respirator. Also First to Liquefy Nitrous Oxide. Cadet at
at Time of . Mentioned for the Nobel Prize for Scientific Attainment in Chemistry. Prof. George Poe, a cousin of the poet Edgar Allan Poe, a noted scientist and inventor, who had been mentioned for the Nobel prize for scientific attainment, a former resident of Washington, died in Norfolk, Virginia, yesterday of general paralysis. Prof. Poe was in his sixty-eighth year.
. Sanghi Organization 2013.[]
Reimer R. A.; Slaten C. S.; Seapan M.; Lower M. W.; Tomlinson P. E.; (1994). "Abatement of N2O emissions produced in the adipic acid industry". Environmental progress 13 (2): 134–137. :.
Shimizu, A.; Tanaka, K. and Fujimori, M. (2000). "Abatement of N2O emissions produced in the adipic acid industry". Chemosphere – Global Change Science 2 (3–4): 425–434. :.
Suwa T, Matsushima A, Suziki Y and Namina Y (1961). "Synthesis of Nitrous Oxide by Oxidation of Ammonia". Kohyo Kagaku Zasshi, Showa Denka Ltd. 64: .
Egon Wiberg, Arnold Frederick Holleman (2001) Inorganic Chemistry, Elsevier
IPCC, 2006[]
Housecroft, Catherine E. and Sharpe, Alan G. (2008). "Chapter 15: The group 15 elements". Inorganic Chemistry (3rd ed.). Pearson. p. 464.  .
Steinfeld, H.; Gerber, P.; Wassenaar, T.; Castel, V.; Rosales, M. and de Haan, C. (2006). . Fao.org 2008.
. IPCC TAR WG1 2001 2012.
Keys, T.E. (1941). . Anesthesiology 2 (5): 552–574. :. :.[]
Priestley J (1776).
Davy H (1800). . Printed for J. Johnson.
Erving, H. W. (1933). . The Yale journal of biology and medicine 5 (5): 421–430.  .  . 
Wells H (1847). . J. Gaylord Wells.
Desai SP, Desai MS, Pandav CS (2007). . Indian J Anaesth 51 (6): 472–8.
. Center for Cognitive Liberty and Ethics.
Anderton, Jim (26 June 2005). . Beehive.govt.nz.
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