Ionizing (or ionising) radiation is radiation with sufficient energy to remove an electron from an atom or molecule. This ionization produces free radicals, atoms or molecules containing unpaired electrons, which tend to be especially chemically reactive.

The degree and nature of such ionization depends on the energy of the individual particles (including photons), not on their number (intensity). In the absence of heating a bulk substance up to ionization temperature, or multiple absorption of photons (a rare process), an intense flood of particles or particle-waves will not cause ionization if each particle or particle-wave does not carry enough individual energy to be ionizing (an example is a high-powered radio beam, which will not ionize if it does not cause high temperatures). Conversely, even very low-intensity radiation will ionize at low temperatures and powers, if the ''individual particles'' carry enough energy (e.g., a low-powered X-ray beam). Roughly speaking, particles or photons with energies above a few electron volts (eV) are ionizing, no matter what their intensity.

Examples of ionizing particles are alpha particles, beta particles, neutrons, and cosmic rays. The ability of an electromagnetic wave (photons) to ionize an atom or molecule depends on its frequency, which determines the energy of its associated particle, the photon. Radiation on the short-wavelength end of the electromagnetic spectrum—high-frequency ultraviolet, X-rays, and gamma rays—is ionizing, due to its composition of high-energy photons. Lower-energy radiation, such as visible light, infrared, microwaves, and radio waves, are not ionizing. The latter types of low-energy non-ionizing radiation may damage molecules, but the effect is generally indistinguishable from the effects of simple heating. Such heating does not produce free radicals until higher temperatures (for example, flame temperatures or "browning" temperatures, and above) are attained. In contrast, damage done by ionizing radiation produces free radicals, even at room temperatures and below, and production of such free radicals is the reason these and other ionizing radiations produce quite different types of chemical effects from (low-temperature) heating. Free radical production is also a primary basis for the particular danger to biological systems of relatively small amounts of ionizing radiation that are far smaller than needed to produce significant heating. Free radicals easily damage DNA, and ionizing radiation may also directly damage DNA by ionizing or breaking DNA molecules.

Ionizing radiation is ubiquitous in the environment, and also comes from radioactive materials, X-ray tubes, and particle accelerators. It is invisible and not directly detectable by human senses, so instruments such as Geiger counters are usually required to detect its presence. In some cases it may lead to secondary emission of visible light upon interaction with matter, such as in Cherenkov radiation and radioluminescence. It has many practical uses in medicine, research, construction, and other areas, but presents a health hazard if used improperly. Exposure to radiation causes damage to living tissue, and can result in mutation, radiation sickness, cancer, and death.

Types

Various types of ionizing radiation may be produced by radioactive decay, nuclear fission and nuclear fusion, and by particle accelerators and naturally occurring cosmic rays. Muons and many types of mesons (in particular charged pions) are also ionizing.

In order for a particle to be ionizing, it must both have a high enough energy and interact with the atoms of a target.

Photons interact electromagnetically with charged particles, so photons of sufficiently high energy also are ionizing. The energy at which this begins to happen with photons (light) is in the high frequency end of the ultraviolet region of the electromagnetic spectrum.

Charged particles such as electrons, positrons, muons, protons, alpha particles, and heavy atomic nuclei from accelerators or cosmic rays also interact electromagnetically with electrons of an atom or molecule. Muons contribute to background radiation due to cosmic rays, but by themelves are thought to be of little hazard importance due to their relatively low dose. Pions (another very short-lived sometimes-charged particle) may be produced in large amounts in the largest particle accelerators. Pions are not a theoretical biological hazard except near such operating machines, which are then subject to heavy security.

Neutrons, on the other hand, having zero electrical charge, do not interact electromagnetically with electrons, and so they cannot directly cause ionization by this mechanism. However, fast neutrons will interact with the protons in hydrogen (in the manner of a billiard ball hitting another, head on, sending it away with all of the first ball's energy of motion), and this mechanism produces proton radiation (fast protons). These protons are ionizing because they are charged, and interact with the electrons in matter.

A neutron can also interact with other atomic nuclei, depending on the nucleus and the neutron's velocity; these reactions happen with fast neutrons and slow neutrons, depending on the situation. Neutron interactions in this manner often produce radioactive nuclei, which produce ionizing radiation when they decay, then they can produce chain reactions in the mass that is decaying, sometimes causing a larger effect of ionization.

350px|left|thumb|Types of radiation - gamma rays are represented by wavy lines, charged particles and neutrons by straight lines. The little circles show where ionization processes occur.

An ionization event normally produces a positive atomic ion and an electron. High-energy beta particles may produce bremsstrahlung when passing through matter, or secondary electrons (δ-electrons); both can ionize in turn. Energetic Beta-particles. like those emitted by ³²P, are quickly decelerated when passing through matter. The energy lost to deceleration is emitted in the form of X-rays called "Bremsstrahlung" which translates "Braking Radiation". Bremsstrahlung is of concern when shielding beta emitters. The intensity of bremsstrahlung increases with the increase in energy of the electrons or the atomic number of the absorbing medium.

Unlike alpha or beta particles (see particle radiation), gamma rays do not ionize all along their path, but rather interact with matter in one of three ways: the photoelectric effect, the Compton effect, and pair production. By way of example, the figure shows Compton effect: two Compton scatterings that happen sequentially. In every scattering event, the gamma ray transfers energy to an electron, and it continues on its path in a different direction and with reduced energy.

In the same figure, the neutron collides with a proton of the target material, and then becomes a fast recoil proton that ionizes in turn. At the end of its path, the neutron is captured by a nucleus in an (n,γ)-reaction that leads to a neutron capture photon.

General biological effects by type and dose

See the Biological effects section below for detail.

Non-ionizing radiation is thought to be essentially harmless below the levels that cause heating. Ionizing radiation is dangerous in direct exposure, although the degree of danger is a subject of debate.

The negatively-charged electrons and positively charged ions created by ionizing radiation may cause damage in living tissue. If the dose is sufficient, the effect may be seen almost immediately, in the form of radiation poisoning. See criticality accident for a number of cases of accidental radiation poisoning and their outcomes.

Lower doses may cause cancer or other long-term problems. The effect of the very low doses encountered in normal circumstances (from both natural and artificial sources, like cosmic rays, medical X-rays and nuclear power plants) is a subject of current debate. A 2005 report released by the U.S. National Research Council (the BEIR VII report, summarized in ) indicated that the overall cancer risk associated with background sources of radiation was relatively low. Some even propose that low-level doses of ionizing radiation are beneficial, by stimulating the immune system and self-repair mechanisms of cells. This hypothesis is called radiation hormesis.

Radioactive materials usually release alpha particles (which are the nuclei of helium), beta particles (which are quickly moving electrons or positrons), or gamma rays. Alpha and beta particles can often be stopped by a piece of paper or a sheet of aluminium, respectively. They cause most damage when they are emitted inside the human body. Gamma rays are less ionizing than either alpha or beta particles, but protection against gammas requires thicker shielding. The damage they produce is similar to that caused by X-rays, and include burns and also cancer, through mutations. Human biology resists germline mutation by either correcting the changes in the DNA or inducing apoptosis in the mutated cell.

Animals (including humans) can also be exposed to ionizing radiation internally: if radioactive isotopes are present in the environment, they may be taken into the body. For example, radioactive iodine is treated as normal iodine by the body and used by the thyroid; its accumulation there often leads to thyroid cancer. Some radioactive elements also bioaccumulate.

Units

+Weighting factors WR for equivalent dose
Radiation	R
x-rays, gamma rays, electrons, positrons, muons		1
rowspan="5">neutrons	Electronvolt>eV
10–100 keV	10
100 keV – 2 MeV	20
2–20 MeV	10
>20 MeV	5
protons	>2 MeV
alpha particles, Fission product	fission fragments, heavy nuclei

The units used to measure ionizing radiation are rather complex. The ionizing effects of radiation are measured by units of exposure:

The coulomb per kilogram (C/kg) is the SI unit of ionizing radiation exposure, and measures the amount of radiation required to create 1 coulomb of charge of each polarity in 1 kilogram of matter.

The roentgen (R) is an older traditional unit that is almost out of use, which represented the amount of radiation required to liberate 1 esu of charge of each polarity in 1 cubic centimeter of dry air. 1 Roentgen = 2.58×10⁻⁴ C/kg

However, the amount of damage done to matter (especially living tissue) by ionizing radiation is more closely related to the amount of energy deposited rather than the charge. This is called the absorbed dose.

The gray (Gy), with units J/kg, is the SI unit of absorbed dose, which represents the amount of radiation required to deposit 1 joule of energy in 1 kilogram of any kind of matter.

The rad (radioactivity absorbed dose), is the corresponding traditional unit which is 0.01 J deposited per kg. 100 rad = 1 Gy.

Equal doses of different types or energies of radiation cause different amounts of damage to living tissue. For example, 1 Gy of alpha radiation causes about 20 times as much damage as 1 Gy of X-rays. Therefore the equivalent dose was defined to give an approximate measure of the biological effect of radiation. It is calculated by multiplying the absorbed dose by a weighting factor W_R which is different for each type of radiation (see above table).

The sievert (Sv) is the SI unit of equivalent dose. Although it has the same units as the gray, J/kg, it measures something different. It is the dose of a given type of radiation in Gy that has the same biological effect on a human as 1 Gy of x-rays or gamma radiation.

The rem (Roentgen equivalent man) is the traditional unit of equivalent dose. 1 sievert = 100 rem. Because the rem is a relatively large unit, typical equivalent dose is measured in millirem (mrem), 10⁻³ rem, or in microsievert (μSv), 10⁻⁶ Sv. 1 mrem = 10 μSv.

A unit sometimes used for low level doses of radiation is the BRET (Background Radiation Equivalent Time). This is the number of days of an average person's background radiation exposure the dose is equivalent to. This unit is apparently not standardized, and depends on the value used for the average background radiation dose. Using the 2000 UNSCEAR value (below), one BRET unit is equal to about 6.6 μSv.

For comparison, the average 'background' dose of natural radiation received by a person is around 2.4 mSv (240 mrem) per year (3.6 mSv (360 mrem) per year in the USA). The lethal full-body dose of radiation for a human is around 4–5 Sv (400–500 rem).

Uses

Ionizing radiation has many uses, including killing cancerous cells and power generation. However, although ionizing radiation has many applications, overuse can be hazardous to human health. For example, at one time, assistants in shoe shops used X-rays to check a child's shoe size, but this practice was halted when it was discovered that ionizing radiation was dangerous.

Nuclear power

Nuclear reactors produce large quantities of ionizing radiation as a byproduct of fission during operation. In addition, they produce highly radioactive nuclear waste, which will emit ionizing radiation for thousands of years for some of the fission products. The safe disposal of this waste in a way that protects future generations from exposure to its radiation is currently imperfect, a highly controversial and arguably unsolved worldwide problem of this technology.

Radiation emissions from nuclear waste decrease extremely slowly. Waste from nuclear reactors is highly radioactive and has to be contained and stored safely for hundreds of thousands of years while this process occurs. While some sources indicate that radioactive emissions from nuclear power plants under normal conditions of operation are lower than radioactive emissions from coal-burning power producers, dangerous amounts of radioactivity have been released during different nuclear accidents. Radioactive waste does not contain the same toxic substances found in the waste byproducts from fossil-fueled generators, but plutonium, which is produced in nuclear reactors, is also a powerful chemical poison.

Industrial measurement

Since some ionizing radiation (principly gamma) can penetrate matter, they are used for a variety of measuring methods.

X-rays and gamma rays are used to make images of the inside of solid products, as a means of nondestructive testing and inspection. The piece to be radiographed is placed between the source and a photographic film in a cassette. After a certain exposure time, the film is developed and it shows internal defects of the material if there are any.

;Gauges :Gauges use the exponential absorption law of gamma rays :*Level indicators: Source and detector are placed at opposite sides of a container, indicating the presence or absence of material in the horizontal radiation path. Beta or gamma sources are used, depending on the thickness and the density of the material to be measured. The method is used for containers of liquids or of grainy substances :*Thickness gauges: if the material is of constant density, the signal measured by the radiation detector depends on the thickness of the material. This is useful for continuous production, like of paper, rubber, etc.

Applications using ionization of gases by radiation

:*To avoid the build-up of static electricity in production of paper, plastics, synthetic textiles, etc., a ribbon-shaped source of the alpha emitter ²⁴¹Am can be placed close to the material at the end of the production line. The source ionizes the air to remove electric charges on the material. :*Smoke detector: Two ionisation chambers are placed next to each other. Both contain a small source of ²⁴¹Am that gives rise to a small constant current. One is closed and serves for comparison, the other is open to ambient air; it has a gridded electrode. When smoke enters the open chamber, the current is disrupted as the smoke particles attach to the charged ions and restore them to a neutral electrical state. This reduces the current in the open chamber. When the current drops below a certain threshold, the alarm is triggered. :*Radioactive tracers for industry: Since radioactive isotopes behave, chemically, mostly like the inactive element, the behavior of a certain chemical substance can be followed by ''tracing'' the radioactivity. Examples: :**Adding a gamma tracer to a gas or liquid in a closed system makes it possible to find a hole in a tube. :**Adding a tracer to the surface of the component of a motor makes it possible to measure wear by measuring the activity of the lubricating oil.

Medical, biological and sterilization applications

The largest use of ionizing radiation in medicine is in medical radiography to make images of the inside of the human body using x-rays. This is the largest artificial source of radiation exposure for humans. Radiation is also used to treat diseases in radiation therapy. Tracer methods (mentioned above) are used in nuclear medicine to diagnose diseases, and widely used in biological research.

In biology and agriculture, radiation is used to induce mutations to produce new or improved species. Another use in insect control is the sterile insect technique, where male insects are sterilized by radiation and released, so they have no offspring, to reduce the population.

In industrial and food applications, radiation is used for sterilization of tools and equipment. An advantage is that the object may be sealed in plastic before sterilization. An emerging use in food production is the sterilization of food using food irradiation.

Detractors of food irradiation have concerns about the health hazards of induced radioactivity. Alternatively, a report for the American Council on Science and Health entitled "Irradiated Foods" states: "The types of radiation sources approved for the treatment of foods have specific energy levels well below that which would cause any element in food to become radioactive. Food undergoing irradiation does not become any more radioactive than luggage passing through an airport X-ray scanner or teeth that have been X-rayed."

Sources

Natural and artificial radiation sources are similar in their effects on matter.

The average exposure for Americans is about 360 mrem (3.6 mSv) per year, 81 percent of which comes from natural sources of radiation. The remaining 19 percent results from exposure to human-made radiation sources such as medical X-rays, most of which is deposited in people who have CT scans. However, in some areas, the average background dose can be over 1,000 mrem (10 mSv) per year. An important source of natural radiation is radon gas, which seeps continuously from bedrock but can, because of its high density, accumulate in poorly ventilated houses.

The background rate for radiation varies considerably with location, being as low as 1.5 mSv/a (1.5 mSv per year) in some areas and over 100 mSv/a in others. People in some parts of Ramsar, a city in northern Iran, receive an annual absorbed dose from background radiation that is up to 260 mSv/a. Despite having lived for many generations in these high background areas, inhabitants of Ramsar show no significant cytogenetic differences compared to people in normal background areas. This has led to the suggestion that high but steady levels of radiation are easier for humans to sustain than sudden radiation bursts.

Natural background radiation

Natural background radiation comes from five primary sources: cosmic radiation, solar radiation, external terrestrial sources, radiation in the human body and radon.

Cosmic radiation

The Earth, and all living things on it, are constantly bombarded by radiation from outside our solar system. This cosmic radiation consists of positively-charged ions from protons to iron nuclei. The energy of this radiation can far exceed that which humans can create even in the largest particle accelerators (see ultra-high-energy cosmic ray). This radiation interacts in the atmosphere to create secondary radiation that rains down, including x-rays, muons, protons, alpha particles, pions, electrons, and neutrons.

The dose from cosmic radiation is largely from muons, neutrons, and electrons, with a dose rate that varies in different parts of the world and based largely on the geomagnetic field, altitude, and solar cycle. The cosmic-radiation dose rate on airplanes is so high that, according to the United Nations UNSCEAR 2000 Report (see links at bottom), airline flight crew workers receive more dose on average than any other worker, including those in nuclear power plants.

External terrestrial sources

Most materials on Earth contain some radioactive atoms, even if in small quantities. Most of the dose received from these sources is from gamma-ray emitters in building materials, or rocks and soil when outside. The major radionuclides of concern for terrestrial radiation are isotopes of potassium, uranium, and thorium. Each of these sources has been decreasing in activity since the birth of the Earth.

Internal radiation sources

All Earthly materials that are the building blocks of life contain a radioactive component. As humans, plants and animals consume food, air and water, an inventory of radioisotopes builds up within the organism (see banana equivalent dose). Some radionuclides, like potassium-40, emit a high energy gamma ray that can be measured by sensitive electronic radiation measurement systems. Other radionuclides, like carbon-14, have such a long half-life that they can be used to date the remains of long-dead organisms (such as wood that is thousands of years old). These internal radiation sources contribute to an individual's total radiation dose from natural background radiation.

Radon

Radon-222 is a gas produced by the decay of radium-226. Both are a part of the natural uranium decay chain. Uranium is found in soil throughout the world in varying concentrations. Since radon is a gas, it can accumulate in homes. Accumulation is dependent upon home location as well as building methods. Among non-smokers, Radon is the number one cause of lung cancer and, overall, the second leading cause.

Artificial sources

Above the background level of radiation exposure, the U.S. Nuclear Regulatory Commission (NRC) requires that its licensees limit human-made radiation exposure for individual members of the public to 100 mrem (1 mSv) per year, and limit occupational radiation exposure to adults working with radioactive material to 5,000 mrem (50 mSv) per year. Occupationally exposed individuals are exposed according to the sources with which they work. The radiation exposure of these individuals is carefully monitored with the use of pocket-pen-sized instruments called dosimeters.

Examples of industries where occupational exposure is a concern include:

Airline crew (the most exposed population)

Industrial radiography

Medical radiology and nuclear medicine

Uranium mining

Nuclear power plant and nuclear fuel reprocessing plant workers

Research laboratories (government, university and private)

Some human-made radiation sources affect the body through direct radiation, while others take the form of radioactive contamination and irradiate the body from within.

Medical procedures, such as diagnostic X-rays, nuclear medicine, and radiation therapy are by far the most significant source of human-made radiation exposure to the general public. Some of the major radionuclides used are I-131, Tc-99, Co-60, Ir-192, and Cs-137. These are rarely released into the environment. The public also is exposed to radiation from consumer products, such as tobacco (polonium-210), building materials, combustible fuels (gas, coal, etc.), ophthalmic glass , televisions, luminous watches and dials (tritium), airport X-ray systems, smoke detectors (americium), road construction materials, electron tubes, fluorescent lamp starters, and lantern mantles (thorium). A typical dose for radiation therapy might be 7 Gy spread daily (on weekdays) over two months.

Of lesser magnitude, members of the public are exposed to radiation from the nuclear fuel cycle, which includes the entire sequence from mining and milling of uranium to the disposal of the spent fuel. The effects of such exposure have not been reliably measured due to the extremely low doses involved. Estimates of exposure are low enough that proponents of nuclear power liken them to the mutagenic power of wearing trousers for two extra minutes per year (because heat causes mutation). Opponents use a cancer per dose model to assert that such activities cause several hundred cases of cancer per year, an application of the controversial Linear no-threshold model (LNT).

In a nuclear war, gamma rays from fallout of nuclear weapons would probably cause the largest number of casualties. Immediately downwind of targets, doses would exceed 300 Gy per hour. As a reference, 4.5 Gy (around 15,000 times the average annual background rate) is fatal to half of a normal population, without medical treatment.

Some of the radionuclides of concern include cobalt-60, caesium-137, americium-241, and iodine-131.

Biological effects

The biological effects of radiation are thought of in terms of their effects on living cells. For low levels of radiation, the biological effects are so small they may not be detected in epidemiological studies. The body repairs many types of radiation and chemical damage. Biological effects of radiation on living cells may result in a variety of outcomes, including: #Cells experience DNA damage and are able to detect and repair the damage. #Cells experience DNA damage and are unable to repair the damage. These cells may go through the process of programmed cell death, or apoptosis, thus eliminating the potential genetic damage from the larger tissue. #Cells experience a nonlethal DNA mutation that is passed on to subsequent cell divisions. This mutation may contribute to the formation of a cancer. #Cells experience "irreparable DNA damage." Low level ionizing radiation may induce irreparable DNA damage (leading to replicational and transcriptional errors needed for neoplasia or may trigger viral interactions) leading to pre-mature aging and cancer.

Other observations at the tissue level are more complicated. These include: #In some cases, a small radiation dose reduces the impact of a subsequent, larger radiation dose. This has been termed an 'adaptive response' and is related to hypothetical mechanisms of hormesis.

Acute

Acute radiation exposure is an exposure to ionizing radiation which occurs during a short period of time. There are routine brief exposures, and the boundary at which it becomes significant is difficult to identify. Extreme examples include

Instantaneous flashes from nuclear explosions.

Exposures of minutes to hours during handling of highly radioactive sources.

Laboratory and manufacturing accidents.

Intentional and accidental high medical doses.

The effects of acute events are more easily studied than those of chronic exposure.

Chronic

Exposure to ionizing radiation over an extended period of time is called chronic exposure. The term chronic (Greek cronos = time ) refers to the duration, not the magnitude or seriousness. The natural background radiation is chronic exposure, but a normal level is difficult to determine due to variations. Geographic location and occupation often affect chronic exposure.

Radiation levels

The associations between ionizing radiation exposure and the development of cancer are mostly based on populations exposed to relatively high levels of ionizing radiation, such as Japanese atomic bomb survivors, and recipients of selected diagnostic or therapeutic medical procedures.

Cancers associated with high dose exposure include leukemia, thyroid, breast, bladder, colon, liver, lung, esophagus, ovarian, multiple myeloma, and stomach cancers. United States Department of Health and Human Services literature also suggests a possible association between ionizing radiation exposure and prostate, nasal cavity/sinuses, pharyngeal and laryngeal, and pancreatic cancer.

The period of time between radiation exposure and the detection of cancer is known as the latent period. Those cancers that may develop as a result of radiation exposure are indistinguishable from those that occur naturally or as a result of exposure to other carcinogens. Furthermore, National Cancer Institute literature indicates that chemical and physical hazards and lifestyle factors, such as smoking, alcohol consumption, and diet, significantly contribute to many of these same diseases.

Although radiation may cause cancer at high doses and high dose rates, public health data regarding lower levels of exposure, below about 1,000 mrem (10 mSv), are harder to interpret. To assess the health impacts of lower radiation doses, researchers rely on models of the process by which radiation causes cancer; several models have emerged which predict differing levels of risk.

Studies of occupational workers exposed to chronic low levels of radiation, above normal background, have provided mixed evidence regarding cancer and transgenerational effects. Cancer results, although uncertain, are consistent with estimates of risk based on atomic bomb survivors and suggest that these workers do face a small increase in the probability of developing leukemia and other cancers. One of the most recent and extensive studies of workers was published by Cardis, ''et al.'' in 2005 .

The linear dose-response model suggests that any increase in dose, no matter how small, results in an incremental increase in risk. The linear no-threshold model (LNT) hypothesis is accepted by the Nuclear Regulatory Commission (NRC) and the EPA and its validity has been reaffirmed by a National Academy of Sciences Committee (see the BEIR VII report, summarized in ). Under this model, about 1% of a population would develop cancer in their lifetime as a result of ionizing radiation from background levels of natural and man-made sources.

Ionizing radiation damages tissue by causing ionization, which disrupts molecules directly and also produces highly reactive free radicals, which attack nearby cells. The net effect is that biological molecules suffer local disruption; this may exceed the body's capacity to repair the damage and may also cause mutations in cells currently undergoing replication.

Two widely studied instances of large-scale exposure to high doses of ionizing radiation are: atomic bomb survivors in 1945; and emergency workers responding to the 1986 Chernobyl disaster.

Approximately 134 plant workers and fire fighters engaged at the Chernobyl power plant received high radiation doses (70,000 to 1,340,000 mrem or 700 to 13,400 mSv) and suffered from acute radiation sickness. Of these, 28 died from their radiation injuries.

Longer term effects of the Chernobyl disaster have also been studied. There is a clear link (see the UNSCEAR 2000 Report, Volume 2: Effects) between the Chernobyl accident and the unusually large number, approximately 1,800, of thyroid cancers reported in contaminated areas, mostly in children. These were fatal in some cases. Other health effects of the Chernobyl accident are subject to current debate.

In March 2011 an earthquake and tsunami caused damage that led to explosions and partial meltdowns at the Fukushima I Nuclear Power Plant in Japan. Radiation levels at the stricken Fukushima I power plant have varied spiking up to 10,000 mSv/h (millisievert per hour), which is a level that can cause fatal radiation poisoning from less than one hour of exposure. Significant release in emissions of radioactive particles took place following hydrogen explosions at three reactors, as technicians tried to pump in seawater to keep the uranium fuel rods cool, and bled radioactive gas from the reactors in order to make room for the seawater. Concerns about the possibility of a large scale radiation leak resulted in 20 km exclusion zone being set up around the power plant and people within the 20-30km zone being advised to stay indoors. Later, the UK, France and some other countries told their nationals to consider leaving Tokyo, in response to fears of spreading nuclear contamination. ''New Scientist'' has reported that emissions of radioactive iodine and cesium from the crippled Fukushima I nuclear plant have approached levels evident after the Chernobyl disaster in 1986. On March 24, 2011, Japanese officials announced that "radioactive iodine-131 exceeding safety limits for infants had been detected at 18 water-purification plants in Tokyo and five other prefectures".

Ionizing radiation level examples

See: Orders of magnitude (radiation)

Recognized effects of acute radiation exposure are described in the article on radiation poisoning. The exact units of measurement vary, but light radiation sickness begins at about 50–100 rad (0.5–1 gray (Gy), 500–1000 mSv, 50–100 rem, 50,000–100,000 mrem).

Although the SI unit of radiation dose equivalent is the sievert, chronic radiation levels and standards are still often given in millirems, 1/1000 of a rem (1 mrem = 0.01 mSv).

Table A.2 presents a scale of dose levels, with an example of the type of exposure that may cause such a dose, or the special significance of such a dose.

Hormesis

Radiation hormesis is the conjecture that a low level of ionizing radiation (i.e. near the level of Earth's natural background radiation) helps "immunize" cells against DNA damage from other causes (such as free radicals or larger doses of ionizing radiation), and decreases the risk of cancer. The theory proposes that such low levels activate the body's DNA repair mechanisms, causing higher levels of cellular DNA-repair proteins to be present in the body, improving the body's ability to repair DNA damage. This assertion is very difficult to prove in humans (using, for example, statistical cancer studies) because the effects of very low ionizing radiation levels are too small to be statistically measured amid the "noise" of normal cancer rates.

The idea of radiation hormesis is considered unproven by regulatory bodies, which generally use the standard "linear, no threshold" (LNT) model. The LNT model, however, also remains unproven, and was originally created as an administrative convenience, to simplify the process of developing safety standards. The LNT states that risk of cancer is directly proportional to the dose level of ionizing radiation, even at very low levels. The LNT model is perceived to be safer for regulatory purposes because it assumes worst-case damage due to ionizing radiation. Once this assumption is made, the conclusion is that regulations based on it will ensure the protection of workers - that they might be over-protected, but never be under-protected. However, if the LNT does not apply at low levels, it is conceivable that regulations based on it will prevent or limit the hormetic effect, and thus have a negative impact on health.

Monitoring and controlling exposure

Radiation has always been present in the environment and in our bodies. The human body cannot sense ionizing radiation, but a range of instruments exists which are capable of detecting even very low levels of radiation from natural and man-made sources.

Dosimeters measure an absolute dose received over a period of time. Ion-chamber dosimeters resemble pens, and can be clipped to one's clothing. Film-badge dosimeters enclose a piece of photographic film, which will become exposed as radiation passes through it. Ion-chamber dosimeters must be periodically recharged, and the result logged. Film-badge dosimeters must be developed as photographic emulsion so the exposures can be counted and logged; once developed, they are discarded. Another type of dosimeter is the TLD (Thermoluminescent Dosimeter). These dosimeters contain crystals that emit visible light when heated, in direct proportion to their total radiation exposure. Like ion-chamber dosimeters, TLDs can be re-used after they have been 'read'.

Geiger counters and scintillation counters measure the dose rate of ionizing radiation directly.

Limiting exposure

There are three standard ways to limit exposure: # Time: For people who are exposed to radiation in addition to natural background radiation, limiting or minimizing the exposure time will reduce the dose from the radiation source. # Distance: Radiation intensity decreases sharply with distance, according to an inverse-square law (in an absolute vacuum). # Shielding: Air or skin can be sufficient to substantially attenuate low-energy alpha and beta radiation. Barriers of lead, concrete, or water give effective protection from more energetic particles such as gamma rays and neutrons. Some radioactive materials are stored or handled underwater or by remote control in rooms constructed of thick concrete or lined with lead. There are special plastic shields which stop beta particles and air will stop most alpha particles. The effectiveness of a material in shielding radiation is determined by its half-value thicknesses, the thickness of material that reduces the radiation by half. This value is a function of the material itself and of the type and energy of ionizing radiation.

Some generally accepted thicknesses of attenuating material are 5 mm of aluminum for most beta particles, and 3 inches of lead for gamma radiation.

Containment: Radioactive materials are confined in the smallest possible space and kept out of the environment. Radioactive isotopes for medical use, for example, are dispensed in closed handling facilities, while nuclear reactors operate within closed systems with multiple barriers which keep the radioactive materials contained. Rooms have a reduced air pressure so that any leaks occur into the room and not out of it.

In a nuclear war, an effective fallout shelter reduces human exposure at least 1,000 times. Other civil defense measures can help reduce exposure of populations by reducing ingestion of isotopes and occupational exposure during war time. One of these available measures could be the use of potassium iodide (KI) tablets which effectively block the uptake of radioactive iodine into the human thyroid gland.

Spaceflight

During human spaceflights, particularly flights beyond low Earth orbit, astronauts are exposed to both galactic cosmic radiation (GCR) and possibly solar particle event (SPE) radiation. Evidence indicates past SPE radiation levels which would have been lethal for unprotected astronauts. GCR levels which might lead to acute radiation poisoning are less well understood.

Air travel

Air travel exposes people on aircraft to increased radiation from space as compared to sea level, including cosmic rays and from solar flare events. Software programs such as Epcard, CARI, SIEVERT, PCAIRE are attempts to simulate exposure by aircrews and passengers. An example of a measured dose (not simulated dose), is 6 μSv per hour from London Heathrow to Tokyo Narita on a high-latitude polar route. However, dosages can vary, such as during periods of high solar activity. The United States FAA requires airlines to provide flight crew with information about cosmic radiation, and an ICRP recommendation for the general public is no more than 1 mSv per year. In addition, many airlines do not allow pregnant flightcrew members, to comply with a European Directive. The FAA has a recommended limit of 1 mSv total for a pregnancy, and no more than 0.5 mSv per month. Information originally based on ''Fundamentals of Aerospace Medicine'' published in 2008.

See also

Background radiation

Background radiation equivalent time (BRET)

Banana equivalent dose

Civil defense

Electromagnetic radiation

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References

External links

The Nuclear Regulatory Commission regulates most commercial radiation sources and non-medical exposures in the US:

NLM Hazardous Substances Databank – Ionizing Radiation

United Nations Scientific Committee on the Effects of Atomic Radiation 2000 Report Volume 1: Sources, Volume 2: Effects

Beginners Guide to Ionising Radiation Measurement

Radiation Risk Calculator Calculate cancer risk from CT scans and xrays.

Health Physics Society Public Education Website

Oak Ridge Reservation Basic Radiation Facts

Category:Radioactivity Category:Radiobiology Category:Radiation health effects

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Christopher Busby (born 1 September 1945) is a British scientist known for his controversial theories about the negative health effects of very low-dose ionising radiation. Busby is the director of Green Audit, an environmental consultancy agency, and scientific advisor to the Low Level Radiation Campaign (LLRC) which he set up in 1995. Busby is a visiting professor at the University of Ulster. Busby was the National Speaker on Science and Technology for the Green Party of England and Wales.

Career

Busby obtained a BSc in Chemistry with First Class Honours from the University of London, and then did research for the Wellcome Foundation (applying spectroscopic and analytical methods to chemical pharmacology and molecular drug interactions). He became and elected member of the Royal Society of Chemistry. He later gained a PhD in Chemical Physics at the University of Kent, researching Raman spectro-electrochemistry.

In 1999 Busby stood as an Election Candidate for the European Parliamentary elections.

Busby was a member of the British government sponsored Committee Examining Radiation Risks from Internal Emitters (CERRIE), which operated from 2001 to 2004.

In 2001 he was appointed to the UK Ministry of Defence Oversight Committee on Depleted Uranium (DUOB).

In 2003 he was elected a Fellow of the Faculty of Medicine, University of Liverpool, in the Department of Human Anatomy and Cell Biology.

In 2004 he was named Leader of Science Policy for (EU) Policy Information Network for Child Health and Environment PINCHE based in Arnhem, The Netherlands.

Busby is a visiting professor at the School of Biomedical Sciences, University of Ulster researching the toxicity of heavy metals to the human body. In 2008 he was a visiting researcher at the German Federal Research Centre for Cultivated Plants, Julius Kuhn Institute.

According to his CERRIE biography: :As member of the International Society for Environment Epidemiology, he was invited to Iraq and Kosovo to investigate the health effects of depleted uranium in weapons used by allied forces on populations. He has also given presentations on depleted uranium to the Royal Society and to the European Parliament. He was a member of the UK Ministry of Defence Oversight Board on Depleted Uranium."

Busby was the scientific secretary of the European Committee on Radiation Risks, an informal committee based in Brussels, which produced a report for CERRIE.

Second Event Theory and Photoelectric Effect Controversy

320px|thumb|right|''The Biphasic Curve'': The cancer risk vs. radiation level in the low-dose regime (0 to 200 [[Seivert|mSv) for LNT and the promoted by Busby. radiation is ~2.4 mSv/year (diagram adapted by Busby from Burlakova ''et al.'' (1998)).]] From 1987 onwards Busby has worked in particular on the health effects of ionizing radiation, developing the 'Second Event Theory' and 'Photoelectric Effect Theory' which distinguishes between hazards from external radiation and internal irradiation from ingested radioisotopes, upon which he claims the widely accepted linear no-threshold (LNT) model substantially underestimates the risk of low level radiation (the LNT model is largely constructed from the 1958 to 2001 'Life Span Study' of the 120,321 Japanese Atomic Bomb Survivors () who were exposed to a powerful ''external'' burst of neutron and gamma radiation). Busby claims that in the low dose regime, radiation moderately above background causes more cancer than much higher levels of radiation ''i.e.'' a biphasic (bimodal) curve; a claim based on the work of Elena Burlakova.

Busby initially proposed the Second Event Theory (SET) in 1995, in his self-published book 'Wings of Death: Nuclear Pollution and Human Health', in which isotopes that decay sequentially ''i.e.'' emit two or more particles in a short decay chain, have far greater genotoxic effects than predicted by the LNT model. In particular, Busby's SET predicts that the ⁹⁰Sr-⁹⁰Y decay chain might be some ~30 times more carcinogenic than predicted by LNT; because according to Busby primary exposure to a beta particle alters a cells to the G₂ Phase, which he claims are highly radio-sensitive, and a second particle "hit" within a few hours then causes carcinogenesis.

SET was criticized by Cox & Edwards (2000) who pointed out that if Busby's "biologically implausible" theory was correct and ''all'' irradiated cells undergo transformation to the G₂ Phase, it would cause an increased risk factor of just 1.3 times and predict, on the contrary, substantial risk reduction at low doses for single emitting radioisotopes. Furthermore, it was established in 1906 (The Law of Bergonié and Tribondeau) that cells in the G₂ Phase are more resistant to radiation than cells in the M Phase (Radiosensitivity and Cell cycle). The Committee Examining Radiation Risks of Internal Emitters (CERRIE) report, on which Busby was one of twelve members, exhaustively examined the biological plausibility of SET and commissioned an independent consultant to conduct a literature review. In 2004 CERRIE rejected the SET by a 10 to 2 majority consensus (Bramhall and Busby dissented). The rejection was made for following reasons:

The lack of biological plausibility for the basic preconditions of the SET

The paucity of supporting evidence in the proponents’ reviews of the SET

The weakness of studies cited in support of the SET

The absence of supporting evidence found by the independent review commissioned by the Committee

CERRIE also considered and rejected by 10 to 2 consensus the the biphasic (bimodal) curve of Burlakova ''et al.'' (1999), due to the studies "substantial shortcomings".

Busby responded by publishing a 3 person minority report on his website, which claims internal low-level radiation is 300 times more dangerous than predicted, the currently accepted LNT model is meaningless, and in Sweden and Belarus cancer rates have risen by 40% since Chernobyl.

Later work by Busby focused on the health effects of ingested Depleted Uranium particles. In particular he proposes that ingested Uranium particles cause photoelectric enhancement that increases the genotoxic effect of natural background gamma radiation by 500 to 1000 times (he claims natural gamma rays strike Uranium and generate via the photoelectric effect secondary electrons that damage cells). Recent work by Busby (2008) focusing on the photoelectric enhancement as a mechanism of cells damaged by ingested Uranium particles has been covered by ''New Scientist'' magazine, with most of the scientists quoted in response expressing interest but also some skepticism that the effect could be as large as claimed. Additionally, according to Busby, photoelectric enhancement is not limited to radioactive isotopes but involves all heavy atoms (high-Z) ''e.g.'' stable platinum particles from catalytic converters are similarly theoretically capable of enhancing the effects of natural gamma radiation if ingested.

However, subsequent computer simulations by Pattison, Hugtenburg & Green (2010) indicate a radiation enhancement factor of only 1 to 10 fold for uranium particles, considerably lower than Busby's preliminary estimate. Indeed, a large body of research has accumulated into the efficacy of gold nanoparticle-aided radiation therapy (GNRT), where the effects of radiotherapeutic intense gamma ray and x-ray sources are modestly enhanced via the photoelectric effect by 0.3 to 1.16 fold, a lower range than estimated for uranium particles.

Conflicts with other Low-Dose Radiation researchers

Busby is the author of two self-published books on cancer incidence in Wales, ''Wings of Death'' and ''Wolves of Water''; the latter was lauded in a review published by a group that "aims to provide a safe forum for the critical and open minded discussion of ideas that go beyond conventional paradigms in science, medicine and philosophy [and to] challenge the adequacy of "scientific materialism" as an exclusive basis for knowledge and values." According to the reviewer, described as a former research immunologist, "Busby dissects the workings of the government advisory establishment, the biased science and institutional cover-ups of the causes of cancer and other illnesses".

The books were criticised in the Journal of Radiological Protection as "erroneous in consequence of various mistakes". According to Richard Wakeford, the editor-in-chief of the journal, a fellow CERRIE committee member representing the nuclear industy, and a specialist in the health effects of low-dose radiation (formerly with British Nuclear Fuels) :... much of Chris Busby's work is self-published and difficult to access; he seems mainly to avoid publication in the recognised scientific literature, which presents difficulties for a proper review of the evidence underlying his conclusions.".

Busby has since alleged that Wakeford created a website specifically to attack him, using the pseudonym "Richard D". Busby subsequently gained title to the domain.

Busby served on the UK Government's Committee Examining Radiation Risks of Internal Emitters (CERRIE), which operated between 2001 and 2004, and included medical professionals, scientists, delegates from Greenpeace and Friends of the Earth, and Richard Wakeford representing the nuclear industry. Busby ultimately disagreed with the committee's conclusions and published a "minority report" with another committee member from LLRC On the LLRC website page selling the minority report, it's claimed (without citation) that north Sweden cancer rates have increased by 40% since Chernobyl. A doctoral dissertation from 2007 was reported as saying that the area "has shown a small but statistically significant increase in the incidence of cancer."

Busby has criticized other researchers studying health effects from low-dose radiation, for being "stupid" and "ignorant", and in particular Prof. Wade Allison (emeritus) of Oxford who had quoted a UN report saying that only 28 people have died as of 2005 from radiation releases at Chernobyl and who has said there is an "over-reaction" to low-dose radiation. In particular, he seems to have taken exception to Allison on philosophical grounds: :I have chosen to pitch into him since he epitomises and crystallises for us the arguments of the stupid physicist. In this he has done us a favour, since he is really easy to shoot down. All the arguments are in one place. Stupid physicists? Make no mistake, physicists are stupid. They make themselves stupid by a kind of religious belief in mathematical modelling. The old Bertie Russell logical positivist trap.

Busby went on to say, claiming support from a New York Academy of Sciences publication, that "more than a million people have died between 1986 and 2004 as a direct result of Chernobyl." In actuality, the NYAS report was a translation (not put under peer review by NYAS) of a Russian book that, contrary to the UN report cited by Allison, claims several hundred thousand deaths and projects the number to go higher, with some support from mathematical modeling. He can be equivocal about modelling—in earlier comments on BBC, he'd claimed "significant" plutonium releases from Fukushima detected far north of the reactor complex, supposedly established in part through the use of "a very advanced, sophisticated, computer air-flow model."

Antone Brooks (recently retired as the Technical Research Director of the U.S. Department of Energy's Low Dose Radiation Research Program) has also had differences with Busby.

Televised comments on Fukushima I nuclear accidents

In a March 14 broadcast on BBC, Busby was interviewed along with Ian Fells, and characterized the accident as "exactly the same scenario" as Chernobyl. While admitting that the containment structure for Fukushima Dai-ichi was more much advanced than that at Chernobyl, he claimed there could be "nuclear explosion" rather than (as reported) a hydrogen explosion, if fuel elements had melted down and collected at the bottom of the vessel. He also asserted that a brief spike in radiation levels at a reactor north of Fukushima Dai-ichi indicated "up to 100 kilometers away, we are getting concentrations of plutonium, cesium and iodine" (sic - presumably radionuclides thereof) released from Fukushima Dai-ichi, making the releases comparable in his opinion to Chernobyl, in terms of human health impact. In response to Fells' characterization of the worst immediate effects being loss of power to an advanced industrial society, Busby said "this is a radiological catastrophe already", asserting in particular that plutonium releases were the major cause of concern.

On 30 March 2011 Busby first appeared on Russia Today stating that the Fukushima Nuclear Disaster was worse than being reported. During the follow up interview on April 13, 2011, Busby stated that Fukushima radiation pollution could cause up to 400,000 added cancer cases among those living within 200 km of the reactor, with " reports of significant radiation ... even south of Tokyo".

On April 25 Busby stated on Russia Today that he believed one of the explosions at the Fukushima I nuclear reactors was a "nuclear" one, rather than a hydrogen explosion as reported. In the same Russia Today broadcast, he referred to calculations made with his colleagues estimating that Chernobyl had killed 1,400,000 people, and that Fukushima's death toll would be in the same range, if not worse.

Membership/Peak Bodies/Committees

Royal Society of Chemistry Royal Society of Medicine International Society for Environmental Epidemiology Ukraine Committee: Physicians of Chernobyl

(Department of Health and DEFRA) CERRIE Committee Examining Radiation Risk from Internal Emitters 2001-2004 www.cerrie.org

Ministry of Defence DUOB Depleted Uranium Oversight Board 2002-2007 www.duob.org Scientific Secretary: European Committee on Radiation Risk www.euradcom.org Science Policy group Leader: Policy Information Network on Child Health and Environment PINCHE www.pinche.org

Publications

Busby, Chris; Hamdan, Malak; Ariabi, Entesar. (2010) Cancer, Infant Mortality and Birth Sex-Ratio in Fallujah, Iraq 2005–2009. Int. J. Environ. Res. Public Health 7, no. 7: 2828-2837.

Busby C.C. (2009) Very Low Dose Fetal Exposure to Chernobyl Contamination Resulted in Increases in Infant Leukemia in Europe and Raises Questions about Current Radiation Risk Models. International Journal of Environmental Research and Public Health.; 6(12):3105-3114. http://www.mdpi.com/1660-4601/6/12/3105

Busby Chris (2009) Depleted Uranium, Why all the fuss? Disarmament Forum 3 25-33 Geneva: United Nations

Busby Chris, Lengfelder Edmund, Pflugbeil Sebastian, Schmitz Feuerhake, Inge (2009) The evidence of radiation effects in embryos and fetuses exposed by Chernobyl fallout and the question of dose response. Medicine, Conflict, Survival 25(1) 18-39

Busby Chris (2008) Is there a sea coast effect on childhood leukaemia in Dumfries and Galloway, Scotland, 1975-2002 ? Occupational and Environmental Medicine 65, 4, 286-287

Busby Chris and Schnug Ewald (2008) Advanced biochemical and biophysical aspects of uranium contamination. In: (Eds) De Kok, L.J. and Schnug, E. Loads and Fate of Fertilizer Derived Uranium. Backhuys Publishers, Leiden, The Netherlands, ISBN/EAN 978-90-5782-193-6.

Busby C C and Howard CV (2006) ‘Fundamental errors in official epidemiological studies of environmental pollution in Wales’ Journal of Public Health March 22, 2006

Busby C and Fucic A (2006) Ionizing Radiation and children’s health: PINCHE conclusions Acta Paediatrica S 453 81-86

Van den Hazel P, Zuurbier M, Bistrup M L, Busby C, Fucic A, Koppe JG et al (2006) Policy and science in children’s health and environment: Recommendations from the PINCHE project. Acta Paediatrica S 453 114-119

Koppe JG, Bartonova A, Bolte G, Bistrup ML, Busby C, Butter M et al (2006) Exposure to multiple environmental agents and their effects. Acta Paediatrica S 453 106-114

Van den Hazel P, Zuurbier M, Babisch W, Bartonova A, Bistrup M-L, Bolte G, Busby C et al, (2006) ‘Today’s epidemics in children: possible relations to environmental pollution’ Acta Paediatrica S 453 18-26

Elsaesser A, Busby C, McKerr G and Howard CV (2007) Nanoparticles and radiation. EMBO Conference: Nanoparticles. October 2007 Madrid

C.V.Howard,A.Elsaesser&C.Busby; (2009) Thebiologicalimplicationsofradiation induced photoelectron production, as a function of particle size and composition. International Conference; Royal Society for Chemistry

NanoParticles 2009 www.soci.org/News/~/media/Files/.../Oral_18_32.ashx

Busby CC (2005) Does uranium contamination amplify natural background radiation dose to the DNA? European J. Biology and Bioelectromagnetics. 1 (2) 120-131

Busby CC (2005) Depleted Uranium Weapons, metal particles and radiation dose. European J. Biology and Bioelectromagnetics. 1(1) 82-93

Busby CC and Coghill R (2005) Are there enhanced radioactivity levels near high voltage powerlines? European J. Biology and Bioelectromagnetics. 1(2) Ch 7.

Busby Chris and Bramhall Richard (2005) Is there an excess of childhood cancer in North Wales on the Menai Strait, Gwynedd? Concerns about the accuracy of analyses carried out by the Wales Cancer Intelligence Unit and those using its data. European J. Biology and Bioelectromagnetics. 1(3) 504-526

Busby Chris and Morgan Saoirse (2005) Routine monitoring of air filters at the Atomic Weapons Establishment Aldermaston, UK show increases in Uranium from Gulf War 2 operations. European J. Biology and Bioelectromagnetics 1(4) 650-668

Busby C.C (2002). ‘High Risks at low doses.’ Proceedings of 4th International Conference on the Health Effects of Low-level Radiation: Oxford Sept 24 2002. (London: British Nuclear Energy Society).

Busby, C. C. and Cato, M. S. (2000), ‘Increases in leukemia in infants in Wales and Scotland following Chernobyl: evidence for errors in risk estimates’ Energy and Environment 11(2) 127-139

Busby C.,(2000), ‘Response to Commentary on the Second Event Theory by Busby’ International Journal of Radiation Biology 76 (1) 123-125

Busby C.C. and Cato M.S. (2001) ‘Increases in leukemia in infants in Wales and Scotland following Chernobyl: Evidence for errors in statutory risk estimates and dose response assumptions’. International Journal of Radiation Medicine 3 (1) 23

Busby Chris and Cato, Molly Scott (1998), ‘Cancer in the offspring of radiation workers: exposure to internal radioisotopes may be responsible.’ British Medical Journal 316 1672

Busby C, and M. Scott Cato, (1997)`Death Rates from Leukemia are Higher than Expected in Areas around Nuclear Sites in Berkshire and Oxfordshire’, British Medical Journal, 315 (1997): 309.

Busby, C. (1994), `Increase in Cancer in Wales Unexplained', British Medical Journal, 308: 268.

Busby C and Creighton JA (1982)' Factors influencing the enhancement of Raman spectral intensity from a roughened silver surface'. J.Electroanal. Chem. 133 183-193

Busby CC and Creighton JA (1982)' Efficient silver and gold electrodes for surface enhanced Raman spectral studies' J. Electroanal Chem 140 379-390 Busby CC (1984) J.Electroanal Chem 162 251-262

Busby CC (1984) 'Voltage Induced intensity changes in surface Raman bands from silver electrodes and their variation with excitation frequency'. Surface Science 140 294-306

Books

Busby, C. C. (1992), Low level radiation from the nuclear industry: the biological consequences. (Aberystwyth: Green Audit)

Busby C.C (1992) Peledriad isaf o'er diwydiant niwcliar: yr canleniadau biolegol. (Aberystwyth: Green Audit)

Busby, C. C. (1994), Radiation and Cancer in Wales (Aberystwyth: Green Audit).

Busby, C. C. (1995), Wings of Death: Nuclear Pollution and Human Health (Aberystwyth: Green Audit) ISBN 1-897761-03-1

Busby C.C (2003) ed with Bertell R, Yablokov A, Schmitz Feuerhake I and Scott Cato M. ECRR2003: 2003 recommendations of the European Committee on Radiation Risk- The health effects of ionizing radiation at low dose—Regulator's edition. (Brussels: ECRR-2003) 2004 Translations of the above into French Japanese Russian and Spanish (see www.euradcom.org for details)

Busby CC, with Bramhall R and Scott Cato MS (2000) I don’t know Much about Science: political decision making in scientific and technical areas. Aberystwyth: Green Audit (this book influenced the structure and formation of the CERRIE committee and advocates an oppositional structure to science advisory committees in order to allow for cultural bias in science advice. It has now been carried forward by PINCHE in Europe.).

Busby CC, Bramhall R and Dorfman P (2004) CERRIE Minority Report 2004: Minority Report of the UK Department of Health/ Department of Environment (DEFRA) Committee Examining Radiation Risk from Internal Emitters (CERRIE) Aberystwyth: Sosiumi Press

Busby CC and others (2004) Report of the Committee Examining Radiation Risk from Internal Emitters (CERRIE) Chilton, UK: National Radiological Protection Board

Busby C and Yablokov AV (2006) ECRR 2006. Chernobyl 20 year On. The Health Effects of the Chernobyl Accident. Brussels: ECRR/ Aberystwyth: Green Audit

Busby Chris (2006) Wolves of Water. A Study Constructed from Atomic Radiation, Morality, Epidemiology, Science, Bias, Philosophy and Death. Aberystwyth: Green Audit ISBN 1-897761-26-0

Busby Christo (2009) Our Mother who art in Everything. Poems 2004-8 Llandrinddod Wells, Wales: Sosiumi Press

Busby C and Yablokov AV (2009) ECRR 2006. Chernobyl 20 year On. The Health Effects of the Chernobyl Accident. 2nd Edition Brussels: ECRR/ Aberystwyth: Green Audit ISBN 1-897761-15-5

Busby C, Yablolov AV, Schmitz Feuerhake I, Bertell R and Scott Cato M (2010) ECRR2010 The 2010 Recommendations of the European Committee on Radiation Risk. The Health Effects of Ionizing Radiation at Low Doses and Low Dose Rates. Brussels: ECRR; Aberystwyth Green Audit

Busby C (2010) The health effects of exposure to uranium and uranium weapons. Documents of the ECRR 2010 No 2. Brussels: ECRR download free from www.euradcom.org

Also: Busby C (2004) Nuclear Cover-Ups Video DVD Aberystwyth: Green Audit Films Busby Christo (2009) Songs from a Cold Climate (CD) Aberystwyth: Green Audit See also www.myspace.com/christobusby

Book Chapters

Busby, C. C. (1996a), ‘ in Bramhall, R. (ed.), The Health Effects of Low Level Radiation: Proceedings of a Symposium held at the House of Commons, 24 April 1996 (Aberystwyth: Green Audit).

Busby, C. C. (1998), ‘Enhanced mutagenicity from internal sequentially decaying beta emitters from second event effects.’ In ‘Die Wirkung niedriger Strahlendosen- im kindes-und Jugendalter, in der Medizin, Umwelt ind technik, am Arbeitsplatz’. Proceedings of International Congress of the German Society for Radiation Protection. Eds: Koehnlein W and Nussbaum R. Muenster, 28 March 1998 (Bremen: Gesellschaft fur Strahlenschutz)

Busby C.C and Scott Cato M (1999) 'A Planetary Impact index' in Molly Scott Cato and Miriam Kennett eds. Green Economics- beyond supply and demand to meeting peoples needs. Aberystwyth: Green Audit

Busby C (2004) Depleted Science: the health consequences and mechanisms of exposure to fallout from Depleted Uranium weapons. In The Trojan Horses of Nuclear War Kuepker M and Kraft D eds. Hamburg: GAAA

Busby Chris (2007) New nuclear risk models, real health effects and court cases. pp 35–46 in- Updating International Nuclear Law Eds—Stockinger H, van Dyke JM et al. Vienna: Neuer Wissenschaftlicher Verlag

Busby C (2008) Depleted Uranium. Why all the fuss? United Nations Disarmament Forum Journal UNIDIR, Nov 2008

References

See also

Radiation hormesis

Arnold Gundersen

External links

Low Level Radiation Campaign

Category:British chemists Category:Living people Category:1945 births Category:Radiation health effects researchers