Irradiation is the process by which an object is exposed to
radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes:
* ''electromagnetic radiation'', such as radio waves, microwaves, infrared, vi ...
. The exposure can originate from various sources, including natural sources. Most frequently the term refers to
ionizing radiation, and to a level of radiation that will serve a specific purpose, rather than radiation
exposure
Exposure or Exposures may refer to:
People
* The Exposures, a pseudonym for German electronic musician Jan Jeline
Arts, entertainment, and media Films
* ''Exposure'' (film), a 1932 American film
* ''Exposure'', another name for the 1991 movie ...
to normal levels of
background radiation
Background radiation is a measure of the level of ionizing radiation present in the environment at a particular location which is not due to deliberate introduction of radiation sources.
Background radiation originates from a variety of source ...
. The term irradiation usually excludes the exposure to non-ionizing radiation, such as
infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from aroun ...
,
visible light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 tera ...
,
microwave
Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequency, frequencies between 300 MHz and 300 GHz respectively. Different sources define different fre ...
s from
cellular phone
A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive calls over a radio frequency link whi ...
s or
electromagnetic wave
In physics, electromagnetic radiation (EMR) consists of waves of the electromagnetic (EM) field, which propagate through space and carry momentum and electromagnetic radiant energy. It includes radio waves, microwaves, infrared, (visible ...
s emitted by radio and TV receivers and power supplies.
Applications
Sterilization
If administered at appropriate levels, all forms of
ionizing radiation can
sterilize objects, including medical instruments, disposables such as
syringe
A syringe is a simple reciprocating pump consisting of a plunger (though in modern syringes, it is actually a piston) that fits tightly within a cylindrical tube called a barrel. The plunger can be linearly pulled and pushed along the inside o ...
s, and
sterilize food. Ionizing radiation (
electron beams
Cathode rays or electron beam (e-beam) are streams of electrons observed in discharge tubes. If an evacuated glass tube is equipped with two electrodes and a voltage is applied, glass behind the positive electrode is observed to glow, due to ele ...
,
X-rays
X-rays (or rarely, ''X-radiation'') are a form of high-energy electromagnetic radiation. In many languages, it is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it in 1895 and named it ' ...
and
gamma rays
A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nuclei. It consists of the shortest wavelength electromagnetic waves, typically sh ...
) may be used to kill bacteria in food or other organic material, including blood.
Food irradiation
Food irradiation is the process of exposing food and food packaging to ionizing radiation, such as from gamma rays, x-rays, or electron beams. Food irradiation improves food safety and extends product shelf life (preservation) by effectively ...
, while effective, is seldom used due to problems with public acceptance.
Medicine
Irradiation is used in
diagnostic imaging
Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues ( physiology). Medical imaging seeks to rev ...
,
cancer therapy
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal ble ...
and
blood transfusion
Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but m ...
.
In 2011 researchers found that irradiation was successful in the novel
theranostic
Personalized medicine, also referred to as precision medicine, is a medical model that separates people into different groups—with medical decisions, practices, interventions and/or products being tailored to the individual patient based on thei ...
technique involving co-treatment with
heptamethine dyes Heptamethine dyes are a subclass of chemical compounds within the cyanine dye family and have many uses as fluorescent dyes, particularly in biomedical imaging, the development of theranostics, the individualized treatment of cancerous patients with ...
to elucidate tumor cells and attenuate their growth with minimal side effects.
[Tan X, Luo S, Wang D, et al. A NIR heptamethine Dye with intrinsic cancer targeting, imaging and photosynthesizing properties. Journal of Biomaterials China. 33-7 (2011), pp. 2230-2239.][F. Pene, E. Courtine, A. Cariou, J.P. Mira. Toward theranostics. Crit Care Med, 37 (2009), pp. S50–S58]
Ion implantation
Ion irradiation is routinely used to implant impurities
atom
Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons.
Every solid, liquid, gas ...
s into materials, especially
semiconductor
A semiconductor is a material which has an electrical conductivity value falling between that of a conductor, such as copper, and an insulator, such as glass. Its resistivity falls as its temperature rises; metals behave in the opposite way. ...
s, to modify their properties. This process, usually known
as
ion implantation
Ion implantation is a low-temperature process by which ions of one element are accelerated into a solid target, thereby changing the physical, chemical, or electrical properties of the target. Ion implantation is used in semiconductor device fa ...
, is an important step in the manufacture of silicon
integrated circuits.
Ion irradiation
Ion irradiation means in general using
particle accelerator
A particle accelerator is a machine that uses electromagnetic fields to propel electric charge, charged particles to very high speeds and energies, and to contain them in well-defined particle beam, beams.
Large accelerators are used for fun ...
s to shoot energetic ions on a material.
Ion implantation
Ion implantation is a low-temperature process by which ions of one element are accelerated into a solid target, thereby changing the physical, chemical, or electrical properties of the target. Ion implantation is used in semiconductor device fa ...
is a variety of ion irradiation, as is
swift heavy ions
Swift heavy ions are the components of a type of particle beam with high enough energy that electronic stopping dominates over nuclear stopping.M. Toulemonde, W. Assmann, C. Dufour, A. Meftah, F. Studer, and C. Trautmann,
Experimental phenomena a ...
irradiation from
particle accelerators
A particle accelerator is a machine that uses electromagnetic fields to propel charged particles to very high speeds and energies, and to contain them in well-defined beams.
Large accelerators are used for fundamental research in particle ...
induces
ion tracks
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conven ...
that can be used for
nanotechnology
Nanotechnology, also shortened to nanotech, is the use of matter on an atomic, molecular, and supramolecular scale for industrial purposes. The earliest, widespread description of nanotechnology referred to the particular technological goal o ...
.
Industrial chemistry

Irradiation can be used to
cross-link
In chemistry and biology a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds and the polymers can be either synthetic polymers or natural ...
plastics
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...
or to improve material qualities of
semi-precious stones
A gemstone (also called a fine gem, jewel, precious stone, or semiprecious stone) is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments. However, certain rocks (such as lapis lazuli, opal, a ...
as it is widely practised in
jewelry industry
Jewellery ( UK) or jewelry ( U.S.) consists of decorative items worn for personal adornment, such as brooches, rings, necklaces, earrings, pendants, bracelets, and cufflinks. Jewellery may be attached to the body or the clothes. From a weste ...
. Due to its efficiency,
electron beam processing
Electron-beam processing or electron irradiation (EBI) is a process that involves using electrons, usually of high energy, to treat an object for a variety of purposes. This may take place under elevated temperatures and nitrogen atmosphere. Poss ...
is often used in the irradiation treatment of polymer-based products to improve their mechanical, thermal, and chemical properties, and often to add unique properties.
Cross-linked polyethylene
Cross-linked polyethylene, commonly abbreviated PEX, XPE or XLPE, is a form of polyethylene with cross-links. It is used predominantly in building services pipework systems, hydronic radiant heating and cooling systems, domestic water piping, in ...
pipe (PEX), high-temperature products such as tubing and gaskets, wire and cable jacket curing, curing of composite materials, and crosslinking of tires are a few examples.
Security
During the
2001 anthrax attacks
The 2001 anthrax attacks, also known as Amerithrax (a portmanteau of "America" and " anthrax", from its FBI case name), occurred in the United States over the course of several weeks beginning on September 18, 2001, one week after the September ...
, the
US Postal Service
The United States Postal Service (USPS), also known as the Post Office, U.S. Mail, or Postal Service, is an independent agency of the executive branch of the United States federal government responsible for providing postal service in the U ...
irradiated mail
Irradiated mail is mail that has been deliberately exposed to radiation, typically in an effort to disinfect it. The most notable instance of mail irradiation in the US occurred in response to the 2001 anthrax attacks; the level of radiation chose ...
to protect members of the US government and other possible targets. This was of some concern to people who send digital media through the mail, including artists. According to the ART in Embassies program, "incoming mail is irradiated, and the process destroys slides, transparencies and disks."
Agriculture
After its discovery by Lewis Stadler at the
University of Missouri
The University of Missouri (Mizzou, MU, or Missouri) is a public land-grant research university in Columbia, Missouri. It is Missouri's largest university and the flagship of the four-campus University of Missouri System. MU was founded ...
, irradiation of
seed
A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosper ...
and plant
germplasm
Germplasm are living genetic resources such as seeds or tissues that are maintained for the purpose of animal and plant breeding, preservation, and other research uses. These resources may take the form of seed collections stored in seed banks, t ...
has resulted in creating many widely-grown
cultivars
A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture ...
of
food crop
A crop is a plant that can be grown and harvested extensively for profit or subsistence. When the plants of the same kind are cultivated at one place on a large scale, it is called a crop. Most crops are cultivated in agriculture or hydroponics ...
s worldwide. The process, which consists of striking plant seeds or germplasm with radiation in the form of
X-ray
X-rays (or rarely, ''X-radiation'') are a form of high-energy electromagnetic radiation. In many languages, it is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it in 1895 and named it ' ...
s,
UV waves,
heavy-ion beams, or
gamma ray
A gamma ray, also known as gamma radiation (symbol γ or \gamma), is a penetrating form of electromagnetic radiation arising from the radioactive decay of atomic nucleus, atomic nuclei. It consists of the shortest wavelength electromagnetic wav ...
s, essentially induce lesions of the
DNA, leading to mutations in the
genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ...
. The UN has been an active participant through the
International Atomic Energy Agency
The International Atomic Energy Agency (IAEA) is an intergovernmental organization that seeks to promote the peaceful use of nuclear energy and to inhibit its use for any military purpose, including nuclear weapons. It was established in 1 ...
. Irradiation is also employed to prevent the sprouting of certain
cereal
A cereal is any grass cultivated for the edible components of its grain (botanically, a type of fruit called a caryopsis), composed of the endosperm, germ, and bran. Cereal grain crops are grown in greater quantities and provide more foo ...
s,
onion
An onion (''Allium cepa'' L., from Latin ''cepa'' meaning "onion"), also known as the bulb onion or common onion, is a vegetable that is the most widely cultivated species of the genus ''Allium''. The shallot is a botanical variety of the oni ...
s,
potato
The potato is a starchy food, a tuber of the plant ''Solanum tuberosum'' and is a root vegetable native to the Americas. The plant is a perennial in the nightshade family Solanaceae.
Wild potato species can be found from the southern Un ...
es and
garlic
Garlic (''Allium sativum'') is a species of bulbous flowering plant in the genus ''Allium''. Its close relatives include the onion, shallot, leek, chive, Welsh onion and Chinese onion. It is native to South Asia, Central Asia and northe ...
. Appropriate irradiation doses are also used to produce insects for use in the
sterile insect technique
The sterile insect technique (SIT) is a method of biological insect control, whereby overwhelming numbers of sterile insects are released into the wild. The released insects are preferably male, as this is more cost-effective and the females ...
of pest control.
The
U.S. Department of Agriculture
The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of com ...
's (USDA) Food Safety and Inspection Service (FSIS) recognizes irradiation as an important technology to
protect consumers. Fresh
meat and
poultry
Poultry () are domesticated birds kept by humans for their eggs, their meat or their feathers. These birds are most typically members of the superorder Galloanserae (fowl), especially the order Galliformes (which includes chickens, quail ...
including whole or cut up birds, skinless poultry,
pork chop
A pork chop, like other meat chops, is a loin cut taken perpendicular to the spine of the pig and is usually a rib or part of a vertebra. Pork chops are unprocessed and leaner than other cuts. Chops are commonly served as an individual port ...
s,
roast
Roasting is a cooking method that uses dry heat where hot air covers the food, cooking it evenly on all sides with temperatures of at least from an open flame, oven, or other heat source. Roasting can enhance the flavor through caramelization ...
s,
stew meat
A stew is a combination of solid food ingredients that have been cooked in liquid and served in the resultant gravy. A stew needs to have raw ingredients added to the gravy. Ingredients in a stew can include any combination of vegetables and m ...
, liver,
hamburger
A hamburger, or simply burger, is a food consisting of fillings—usually a patty of ground meat, typically Ground beef, beef—placed inside a sliced bun or bread roll. Hamburgers are often served with cheese, lettuce, tomato, onion, pickles ...
s,
ground meat
Ground meat, called mince or minced meat outside North America, is meat finely chopped by a meat grinder or a chopping knife. A common type of ground meat is ground beef, but many other types of meats are prepared in a similar fashion, incl ...
, and ground poultry are approved for irradiation.
Assassination
Some claim that
Gheorghe Gheorghiu-Dej
Gheorghe Gheorghiu-Dej (; 8 November 1901 – 19 March 1965) was a Romanian communist politician and electrician. He was the first Communist leader of Romania from 1947 to 1965, serving as first secretary of the Romanian Communist Party ...
, who died of lung cancer in Bucharest on March 19, 1965, was intentionally irradiated during a visit to Moscow, due to his political stance.
In 1999, an article in ''
Der Spiegel'' alleged that the East German
MfS MFS may refer to:
Education
* Miletich Fighting Systems, a mixed martial arts training camp founded by Pat Miletich
*Moorestown Friends School, a private Quaker school located in Moorestown, New Jersey
* Moscow Finnish School, a Finnish private ...
intentionally irradiated political prisoners with high-dose radiation, possibly to provoke cancer.
''Tödliche Strahlung. Die Staatssicherheit der DDR steht im Verdacht, Regimegegner radioaktiv verseucht zu haben.''
Article by Paul Leonhard in ''Junge Freiheit'' April 14, 2000
Alexander Litvinenko
Alexander Valterovich "Sasha" Litvinenko (30 August 1962 ( at WebCite) or 4 December 1962 – 23 November 2006) was a British-naturalised Russian defector and former officer of the Russian Federal Security Service (FSB) who specialised in ...
, a secret serviceman who was tackling organized crime in Russia, was intentionally poisoned with polonium-210
Polonium-210 (210Po, Po-210, historically radium F) is an isotope of polonium. It undergoes alpha decay to stable 206Pb with a half-life of 138.376 days (about months), the longest half-life of all naturally occurring polonium isotopes. First ...
; the very large internal doses of radiation he received caused his death.
References
{{reflist
External links
Industrial, Medical & Educational Uses of Radiation
Radiation Protection- US EPA
International Atomic Energy Agency (IAEA)
North American Seed Bank (NASB)
See also
*Dose area product Dose area product (DAP) is a quantity used in assessing the radiation risk from diagnostic X-ray examinations and interventional procedures. It is defined as the absorbed dose multiplied by the area irradiated, expressed in gray- centimetres squared ...
*Food irradiation
Food irradiation is the process of exposing food and food packaging to ionizing radiation, such as from gamma rays, x-rays, or electron beams. Food irradiation improves food safety and extends product shelf life (preservation) by effectively ...
*Gemstone irradiation
Gemstone irradiation is a process in which a gemstone is artificially irradiated in order to enhance its optical properties. High levels of ionizing radiation can change the atomic structure of the gemstone's crystal lattice, which in turn alte ...
*Radiolyse
Radiolysis is the dissociation of molecules by ionizing radiation. It is the cleavage of one or several chemical bonds resulting from exposure to high-energy flux. The radiation in this context is associated with ionizing radiation; radiolysis i ...
Radiobiology
de:Bestrahlung