What is nitrous oxide?
Nitrous oxide (N2O) is a clear, colorless, oxidizing liquefied gas with a slightly sweet odor. The product is stable and inert at room temperature. While classified by the U. S. Department of Transportation (DOT) as a nonflammable gas, nitrous oxide will support combustion and can detonate at temperatures in excess of 650° C (1202° F).
What are the principal applications of nitrous oxide?
Nitrous oxide finds beneficial use in a number of legitimate applications. Following is a listing of the primary "consuming" markets/applications along with approximate shares of total volume consumed by each:
Market Application % of Total
Medicine/Dentistry Anesthesia (analgesic property) 89-90%
Food Processing Propellant 5 - 8%
Other: 3 - 5
- Semiconductor Mfg. Oxidizer used at very high purities
- Analytical Chemistry Oxidizer used with acetylene in atomic absorption spectrometry
- Chemical Mfg. Raw material in production of chemical used to inflate airbags
- Auto Racing Engine injection for boosting horsepower
Nitrous oxide is blended with oxygen when used in anesthesia applications. Pure nitrous oxide will cause asphyxiation, resulting ultimately in respiratory arrest.
Nitrous oxide used in food propellant applications is typically supplied to commercial packagers of pressurized food dispensing containers. It is also packaged in "whippets" (small cartridges) that can be purchased at restaurant supply stores. Restrictions on individual purchases of whippets differ from state to state. One manufacturer of whippets is ISI, an overseas firm. No known whippets manufacturers in the U.S. N2O sold for this application is denatured to deter inhalation.How is N2O made?
Nitrous oxide (N2O) is produced by thermally decomposing ammonium nitrate (NH4NO3), a common ingredient used in fertilizers and explosives. A low-pressure, low-temperature (500° F) reaction decomposes the ammonium nitrate to form steam (H2O) and N2O. The steam is condensed out, and "crude" N2O is then further purified, compressed, dried, and liquefied for storage and distribution.
Who manufactures nitrous oxide in North America?
Puritan-Bennett Corporation (U.S. and Canada)
Nitrous Oxide Corporation (U.S.)
AGA (Mexico)
What is the annual production of nitrous oxide?
Annual production of nitrous oxide in the U.S. ranges between 30 million and 35 million pounds.
How is nitrous oxide shipped, stored, and sold?
Nitrous Oxide producers ship their product as a low pressure liquid to approximately 300 customers, most of whom (» 250) are repackers. Repackers store product in liquid tanks, utilizing pumping facilities to fill gas cylinders or to supply smaller bulk liquid requirements. Nitrous oxide is shipped in cylinders as a gas over liquid (» 745 psi @ 70° F) to other distributors or to end users.
How many locations in the U.S. store nitrous oxide?
Legitimate users include:
Dentists 83,700
Hospitals 7,200
Clinics 2,400
Gas repackagers and distributors 3,200
Other 100
Total 96,600
How big are nitrous oxide cylinders?
Nitrous oxide cylinders range in size from roughly two feet in height to over five feet. Contents range from about six pounds to over sixty pounds of liquid in a large cylinder.
How much does it cost to buy a cylinder of nitrous oxide?
Depending on cylinder size and product purity, legitimate users pay between $40 and $75 per cylinder. (Some grades used in semiconductor processing cost considerably more.)
How does nitrous oxide get into the hands of abusers?
People who profit from nitrous oxide abuse typically steal the cylinders from distributors or legitimate users. Sometimes these profiteers try to legitimize this abuse by illegally obtaining a legitimate nitrous oxide use permit, or obtain the cylinders by misrepresenting themselves as legitimate users.
What is the value of annual sales?
The approximate value of nitrous oxide sold to legitimate consumers is $50 million per year.
Effects of nitrous oxide on the human body
The painkilling and numbing qualities of nitrous oxide that is inhaled begin to take effect when the gas is at concentrations of 10 percent. At higher concentrations, approaching 100 percent, a sense of well-being, or "high," is experienced. A person experiencing a nitrous oxide high may:
Have slurred speech
Have difficulty in maintaining his or her balance or walking
Be slow to respond to questions
Be immune to any stimulus such as pain, loud noises, and speech
Lapse into unconsciousness
A person who is rendered unconscious by nitrous oxide is likely to stop breathing within a few seconds as a result of a depressed central nervous system--brain, brain stem, and spinal cord. Depression is caused by a combination of the effects of nitrous oxide and the lowered oxygen content that occurs as pure N2O displaces oxygen from the lungs with each succeeding inhalation of the gas; i.e., the person is asphyxiated.
If a person remains conscious and stops breathing the nitrous oxide, recovery (full consciousness and alertness) can occur within minutes. A person who loses consciousness, however, and continues to inhale a pure gas (providing a supply is still available) is most likely to die.
Death usually occurs when abusers, in their attempt to achieve a higher state of euphoria, breathe pure N2O in a confined space -- in a small room, inside an automobile or other vehicle cab, or by placing their head inside a plastic bag.
Tragedy can occur very quickly. Long-term exposure (several minutes) is not necessary before death occurs. Sudden, prolonged exposure to high levels of N2O, or a series of inhalations (without breathing clean air between inhalations) can result in death. The length of this action can be measured in seconds. Since the narcotic effect of nitrous oxide is very brief (several seconds) abusers tend to follow this repetitive action pattern.
Scientific explanation of the effects of nitrous oxide on the human body.
Nitrous oxide that is inhaled is absorbed through the lungs and is rapidly distributed throughout the body. A number of chemical reactions take place within the body when various organs tissues, etc., come in contact with nitrous oxide. One of the fundamental, harmful reactions that occur when nitrous oxide enters the body is oxidation. N2O tends to absorb oxygen that is present in the body. This oxidation, or oxygen absorption, results in a vitamin B12 deficiency. When the level of vitamin B12 in the body is reduced, the red blood cell count is lowered, anemia results, and nerves degenerate. A vitamin B12 deficiency causes a person to; have painful sensations in the arms or legs; have an unsteady walk or gait; become unbalanced and tend to fallover; feel or appear to be irritable; suffer intellectual deterioration.
If death does not occur, the person who suffers from these symptoms may recover from all of them. The debilitating process is reversible, although some persons have experienced permanent loss of balance.