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144-408: Nuclear fallout is residual radioactive material propelled into the upper atmosphere following a nuclear blast , so called because it "falls out" of the sky after the explosion and the shock wave has passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes. The amount and spread of fallout is a product of the size of the weapon and the altitude at which it

288-537: A 2003 article in The New York Times states that many scientists consider the group's work controversial, with little credibility with the scientific establishment, while some scientists consider it "good, careful work". In an April 2014 article in Popular Science , Sarah Fecht argues that the group's work, specifically the widely discussed case of cherry-picking data to suggest that fallout from

432-465: A cloud. Nuclear explosions produce high levels of ionizing radiation and radioactive debris that is harmful to humans and can cause moderate to severe skin burns, eye damage, radiation sickness , radiation-induced cancer and possible death depending on how far a person is from the blast radius. Nuclear explosions can also have detrimental effects on the climate, lasting from months to years. A small-scale nuclear war could release enough particles into

576-474: A factor of about 530. In other 1954 tests, including Yankee and Nectar, hot spots were mapped out by ships with submersible probes, and similar hot spots occurred in 1956 tests such as Zuni and Tewa . However, the major U.S. " DELFIC " (Defence Land Fallout Interpretive Code) computer calculations use the natural size distributions of particles in soil instead of the afterwind sweep-up spectrum, and this results in more straightforward fallout patterns lacking

720-428: A factor of ten for every seven-fold increase in the number of hours since the explosion. He presents data showing that "it takes about seven times as long for the dose rate to decay from 1000 roentgens per hour (1000 R/hr) to 10 R/hr (48 hours) as to decay from 1000 R/hr to 100 R/hr (7 hours)." This is a rule of thumb based on observed data, not a precise relation. The United States government, often

864-429: A given material, such as 90 cm (36 inches) of packed earth, which reduces gamma ray exposure by approximately 1024 times (2). A shelter built with these materials for the purposes of fallout protection is known as a fallout shelter . As the nuclear energy sector continues to grow, the international rhetoric surrounding nuclear warfare intensifies, and the ever-present threat of radioactive materials falling into

1008-682: A heavy dose, contaminating reindeer herds in Lapland, and salad greens becoming almost unavailable in France. Some sheep farms in North Wales and the North Of England were required to monitor radioactivity levels in their flocks until the control was lifted in 2012. During detonations of devices at ground level ( surface burst ), below the fallout-free altitude, or in shallow water, heat vaporizes large amounts of earth or water, which

1152-399: A high neutron activation cross section to shield neutrons will result in the shielding material itself becoming radioactive and hence more dangerous than if it were not present. There are many types of shielding strategies that can be used to reduce the effects of radiation exposure. Internal contamination protective equipment such as respirators are used to prevent internal deposition as

1296-539: A higher dose than would otherwise be expected. The dose to the targeted tissue mass must be averaged over the entire body mass, most of which receives negligible radiation, to arrive at a whole-body absorbed dose that can be compared to the table above. Exposure to high doses of radiation causes DNA damage, later creating serious and even lethal chromosomal aberrations if left unrepaired. Ionizing radiation can produce reactive oxygen species , and does directly damage cells by causing localized ionization events. The former

1440-434: A latent period averaging 20 to 40 years. Acute effects of ionizing radiation were first observed when Wilhelm Röntgen intentionally subjected his fingers to X-rays in 1895. He published his observations concerning the burns that developed that eventually healed, and misattributed them to ozone. Röntgen believed the free radical produced in air by X-rays from the ozone was the cause, but other free radicals produced within

1584-431: A latent phase may occur and last from a few days up to several weeks, when intense reddening, blistering , and ulceration of the irradiated site is visible. In most cases, healing occurs by regenerative means; however, very large skin doses can cause permanent hair loss, damaged sebaceous and sweat glands , atrophy , fibrosis (mostly keloids ), decreased or increased skin pigmentation, and ulceration or necrosis of

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1728-458: A major part in radiotherapy accidents. The latter of the two is caused by the failure of equipment software used to monitor the radiational dose given. Human error has played a large part in accidental exposure incidents, including some of the criticality accidents, and larger scale events such as the Chernobyl disaster . Other events have to do with orphan sources , in which radioactive material

1872-499: A memorandum to the U.S. Secretary of War, General Leslie Groves describes the yield as equivalent to 15,000 to 20,000 tons of TNT. Following this test, a uranium-gun type nuclear bomb ( Little Boy ) was dropped on the Japanese city of Hiroshima on August 6, 1945, with a blast yield of 15 kilotons; and a plutonium implosion-type bomb ( Fat Man ) on Nagasaki on August 9, 1945, with a blast yield of 21 kilotons. Fat Man and Little Boy are

2016-569: A more comprehensive study of the elements found in the teeth collected showed that children born after 1963 had levels of strontium-90 in their baby teeth that was 50 times higher than that found in children born before large-scale atomic testing began. The findings helped convince U.S. President John F. Kennedy to sign the Partial Nuclear Test Ban Treaty with the United Kingdom and Soviet Union , which ended

2160-634: A nuclear test. Nuclear tests have taken place at more than 60 locations across the world; some in secluded areas and others more densely populated. Detonation of nuclear weapons (in a test or during war) releases radioactive fallout that concerned the public in the 1950s. This led to the Limited Test Ban Treaty of 1963 signed by the United States, Great Britain, and the Soviet Union. This treaty banned nuclear weapons testing in

2304-433: A person is exposed in a non-homogeneous manner then a given dose (averaged over the entire body) is less likely to be lethal. For instance, if a person gets a hand/low arm dose of 100 Gy, which gives them an overall dose of 4 Gy, they are more likely to survive than a person who gets a 4 Gy dose over their entire body. A hand dose of 10 Gy or more would likely result in loss of the hand. A British industrial radiographer who

2448-554: A person's body, but the radiation from these particles will still permeate through the clothing. For safety clothing to be able to block the fallout radiation, it would have to be so thick and heavy that a person could not function. Nuclear explosion Nuclear explosions are extremely destructive compared to conventional (chemical) explosives, because of the vastly greater energy density of nuclear fuel compared to chemical explosives. They are often associated with mushroom clouds , since any large atmospheric explosion can create such

2592-442: A person's chances for survival if they were unprepared. The central idea in these guides is that materials like concrete, soil, and sand are necessary to shield a person from fallout particles and radiation. A significant amount of materials of this type are necessary to protect a person from fallout radiation, so safety clothing cannot protect a person from fallout radiation. However, protective clothing can keep fallout particles off

2736-432: A radiation cloud at high altitude is exposed to rainfall, the radioactive fallout will contaminate the downwind area below. Agricultural fields and plants will absorb the contaminated material and animals will consume the radioactive material. As a result, the nuclear fallout may cause livestock to become ill or die, and if consumed the radioactive material will be passed on to humans. The damage to other living organism as

2880-501: A recovery period and can perform non-demanding tasks for about six days, after which they relapse for about four weeks. At this time they begin exhibiting symptoms of radiation poisoning of sufficient severity to render them totally ineffective. Death follows at approximately six weeks after exposure, although outcomes may vary. Late or delayed effects of radiation occur following a wide range of doses and dose rates. Delayed effects may appear months to years after irradiation and include

3024-467: A reduction in dose rate below 0.1 Gy/h also tends to reduce cell death. This technique is routinely used in radiotherapy. The human body contains many types of cells and a human can be killed by the loss of a single type of cells in a vital organ. For many short term radiation deaths (3–30 days), the loss of two important types of cells that are constantly being regenerated causes death. The loss of cells forming blood cells ( bone marrow ) and

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3168-533: A result of a Castle Bravo surface burst of a 15 Mt thermonuclear device at Bikini Atoll on March 1, 1954, a roughly cigar-shaped area of the Pacific extending over 500 km downwind and varying in width to a maximum of 100 km was severely contaminated. There are three very different versions of the fallout pattern from this test, because the fallout was measured only on a small number of widely spaced Pacific Atolls. The two alternative versions both ascribe

3312-486: A result of inhalation and ingestion of radioactive material. Dermal protective equipment, which protects against external contamination, provides shielding to prevent radioactive material from being deposited on external structures. While these protective measures do provide a barrier from radioactive material deposition, they do not shield from externally penetrating gamma radiation. This leaves anyone exposed to penetrating gamma rays at high risk of ARS. Naturally, shielding

3456-449: A result to nuclear fallout depends on the species. Mammals particularly are extremely sensitive to nuclear radiation, followed by birds, plants, fish, reptiles, crustaceans, insects, moss, lichen, algae, bacteria, mollusks, and viruses. Climatologist Alan Robock and atmospheric and oceanic sciences professor Brian Toon created a model of a hypothetical small-scale nuclear war that would have approximately 100 weapons used. In this scenario,

3600-448: A short period of time (> ~0.1 Gy/h). Alpha and beta radiation have low penetrating power and are unlikely to affect vital internal organs from outside the body. Any type of ionizing radiation can cause burns, but alpha and beta radiation can only do so if radioactive contamination or nuclear fallout is deposited on the individual's skin or clothing. Gamma and neutron radiation can travel much greater distances and penetrate

3744-432: A short period of time. Symptoms can start within an hour of exposure, and can last for several months. Early symptoms are usually nausea, vomiting and loss of appetite. In the following hours or weeks, initial symptoms may appear to improve, before the development of additional symptoms, after which either recovery or death follow. ARS involves a total dose of greater than 0.7 Gy (70 rad ), that generally occurs from

3888-655: A source outside the body, delivered within a few minutes. Sources of such radiation can occur accidentally or intentionally. They may involve nuclear reactors , cyclotrons , certain devices used in cancer therapy , nuclear weapons , or radiological weapons . It is generally divided into three types: bone marrow, gastrointestinal, and neurovascular syndrome, with bone marrow syndrome occurring at 0.7 to 10 Gy, and neurovascular syndrome occurring at doses that exceed 50 Gy. The cells that are most affected are generally those that are rapidly dividing. At high doses, this causes DNA damage that may be irreparable. Diagnosis

4032-572: A third- or fourth-generation cephalosporin with pseudomonal coverage: e.g., cefepime , ceftazidime , or an aminoglycoside: i.e. gentamicin , amikacin ). The prognosis for ARS is dependent on the exposure dose, with anything above 8 Gy being almost always lethal, even with medical care. Radiation burns from lower-level exposures usually manifest after 2 months, while reactions from the burns occur months to years after radiation treatment. Complications from ARS include an increased risk of developing radiation-induced cancer later in life. According to

4176-485: A total of 1.5 Gy are not incapacitated. People receiving doses greater than 1.5 Gy become disabled, and some eventually die. A dose of 5.3 Gy to 8.3 Gy is considered lethal but not immediately incapacitating. Personnel exposed to this amount of radiation have their cognitive performance degraded in two to three hours, depending on how physically demanding the tasks they must perform are, and remain in this disabled state at least two days. However, at that point they experience

4320-410: A variable period of time until the development of delayed radiation effects, in a portion of the exposed population, following low dose exposures. The unit of actual exposure is the röntgen , defined in ionisations per unit volume of air. All ionisation based instruments (including geiger counters and ionisation chambers ) measure exposure. However, effects depend on the energy per unit mass, not

4464-449: A wide variety of effects involving almost all tissues or organs. Some of the possible delayed consequences of radiation injury, with the rates above the background prevalence, depending on the absorbed dose, include carcinogenesis , cataract formation, chronic radiodermatitis , decreased fertility , and genetic mutations . Presently, the only teratological effect observed in humans following nuclear attacks on highly populated areas

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4608-514: Is microcephaly which is the only proven malformation, or congenital abnormality, found in the in utero developing human fetuses present during the Hiroshima and Nagasaki bombings. Of all the pregnant women who were close enough to be exposed to the prompt burst of intense neutron and gamma doses in the two cities, the total number of children born with microcephaly was below 50. No statistically demonstrable increase of congenital malformations

4752-625: Is 1 cGy. Some lower values reported for the amount of radiation that would kill 50% of personnel (the LD 50 ) refer to bone marrow dose, which is only 67% of the air dose. The dose that would be lethal to 50% of a population is a common parameter used to compare the effects of various fallout types or circumstances. Usually, the term is defined for a specific time, and limited to studies of acute lethality. The common time periods used are 30 days or less for most small laboratory animals and to 60 days for large animals and humans. The LD 50 figure assumes that

4896-406: Is a form of radioactive contamination . Fallout comes in two varieties. The first is a small amount of carcinogenic material with a long half-life . The second, depending on the height of detonation, is a large quantity of radioactive dust and sand with a short half-life. All nuclear explosions produce fission products, un-fissioned nuclear material, and weapon residues vaporized by the heat of

5040-414: Is almost exclusively concerned with protection from radiation. Radiation from a fallout is encountered in the forms of alpha , beta , and gamma radiation, and as ordinary clothing affords protection from alpha and beta radiation, most fallout protection measures deal with reducing exposure to gamma radiation. For the purposes of radiation shielding, many materials have a characteristic halving thickness :

5184-431: Is based on a history of exposure and symptoms. Repeated complete blood counts (CBCs) can indicate the severity of exposure. Treatment of ARS is generally supportive care . This may include blood transfusions , antibiotics , colony-stimulating factors , or stem cell transplant . Radioactive material remaining on the skin or in the stomach should be removed. If radioiodine was inhaled or ingested, potassium iodide

5328-415: Is detonated. Fallout may get entrained with the products of a pyrocumulus cloud and when combined with precipitation falls as black rain (rain darkened by soot and other particulates), which occurred within 30–40 minutes of the atomic bombings of Hiroshima and Nagasaki . This radioactive dust, usually consisting of fission products mixed with bystanding atoms that are neutron-activated by exposure ,

5472-659: Is difficult because of confounding factors. ARS may be accompanied by conventional injuries such as steam burns, or may occur in someone with a pre-existing condition undergoing radiotherapy. There may be multiple causes for death, and the contribution from radiation may be unclear. Some documents may incorrectly refer to radiation-induced cancers as radiation poisoning, or may count all overexposed individuals as survivors without mentioning if they had any symptoms of ARS. The following table includes only those known for their attempted survival with ARS. These cases exclude chronic radiation syndrome such as Albert Stevens , in which radiation

5616-443: Is divided into three main presentations: hematopoietic , gastrointestinal , and neuro vascular . These syndromes may be preceded by a prodrome . The speed of symptom onset is related to radiation exposure, with greater doses resulting in a shorter delay in symptom onset. These presentations presume whole-body exposure, and many of them are markers that are invalid if the entire body has not been exposed. Each syndrome requires that

5760-638: Is drawn up into the radioactive cloud . This material becomes radioactive when it combines with fission products or other radio-contaminants, or when it is neutron-activated . The table below summarizes the abilities of common isotopes to form fallout. Some radiation taints large amounts of land and drinking water causing formal mutations throughout animal and human life. A surface burst generates large amounts of particulate matter, composed of particles from less than 100 nm to several millimeters in diameter—in addition to very fine particles that contribute to worldwide fallout. The larger particles spill out of

5904-577: Is during the 1999 Tokaimura nuclear accident , where technician Hisashi Ouchi had lost a majority of his skin due to the high amounts of radiation he absorbed during the irradiation. This effect had been demonstrated previously with pig skin using high energy beta sources at the Churchill Hospital Research Institute, in Oxford . ARS is caused by exposure to a large dose of ionizing radiation (> ~0.1 Gy) over

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6048-683: Is especially harmful. While DNA damage happens frequently and naturally in the cell from endogenous sources, clustered damage is a unique effect of radiation exposure. Clustered damage takes longer to repair than isolated breakages, and is less likely to be repaired at all. Larger radiation doses are more prone to cause tighter clustering of damage, and closely localized damage is increasingly less likely to be repaired. Somatic mutations cannot be passed down from parent to offspring, but these mutations can propagate in cell lines within an organism. Radiation damage can also cause chromosome and chromatid aberrations, and their effects depend on in which stage of

6192-469: Is exposed to a given subject over a long duration. The table also necessarily excludes cases where the individual was exposed to so much radiation that death occurred before medical assistance or dose estimations could be made, such as an attempted cobalt-60 thief who reportedly died 30 minutes after exposure. The result column represents the time of exposure to the time of death attributed to the short and long term effects attributed to initial exposure. As ARS

6336-467: Is not hazardous once fallout is no longer being deposited. For example, assume the shelter is in an area of heavy fallout and the dose rate outside is 400  roentgen (R) per hour, enough to give a potentially fatal dose in about an hour to a person exposed in the open. If a person needs to be exposed for only 10 seconds to dump a bucket, in this 1/360 of an hour he will receive a dose of only about 1 R. Under war conditions, an additional 1-R dose

6480-399: Is of little concern." In peacetime, radiation workers are taught to work as quickly as possible when performing a task that exposes them to radiation. For instance, the recovery of a radioactive source should be done as quickly as possible. Usually, matter attenuates radiation, so placing any mass (e.g., lead, dirt, sandbags, vehicles, water, even air) between humans and the source will reduce

6624-428: Is only necessary to protect enough bone marrow to repopulate the exposed areas of the body with the shielded supply. This concept allows for the development of lightweight mobile radiation protection equipment, which provides adequate protection, deferring the onset of ARS to much higher exposure doses. One example of such equipment is the 360 gamma , a radiation protection belt that applies selective shielding to protect

6768-510: Is rarer, with an event possibly occurring during the solar storm of 1859 . Intentional exposure is controversial as it involves the use of nuclear weapons , human experiments , or is given to a victim in an act of murder. The intentional atomic bombings of Hiroshima and Nagasaki resulted in tens of thousands of casualties; the survivors of these bombings are known today as hibakusha . Nuclear weapons emit large amounts of thermal radiation as visible, infrared, and ultraviolet light, to which

6912-506: Is recommended. Complications such as leukemia and other cancers among those who survive are managed as usual. Short-term outcomes depend on the dose exposure. ARS is generally rare. A single event can affect a large number of people, as happened in the atomic bombings of Hiroshima and Nagasaki and the Chernobyl nuclear power plant disaster . ARS differs from chronic radiation syndrome , which occurs following prolonged exposures to relatively low doses of radiation. Classically, ARS

7056-402: Is reduced by 50% in the first hour after a detonation, then by 80% during the first day. As a result, early gross decontamination , such as removing contaminated articles of outer clothing, is more effective than delayed but more thorough cleaning. Most areas become fairly safe for travel and decontamination after three to five weeks. One hour after a surface burst, the radiation from fallout in

7200-445: Is reduced where the downwind distance is increased by higher winds. The total amount of activity deposited up to any given time is the same irrespective of the wind pattern, so overall casualty figures from fallout are generally independent of winds. But thunderstorms can bring down activity as rain allows fallout to drop more rapidly, particularly if the mushroom cloud is low enough to be below ("washout"), or mixed with ("rainout"),

7344-474: Is termed nuclear winter . The idea became popularized in mainstream culture during the 1980s, when Richard P. Turco , Owen Toon , Thomas P. Ackerman, James B. Pollack and Carl Sagan collaborated and produced a scientific study which suggested the Earth's weather and climate can be severely impacted by nuclear war. The main idea is that once a conflict begins and the aggressors start detonating nuclear weapons,

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7488-507: Is the whole-body absorbed dose . Several related quantities, such as the equivalent dose , effective dose , and committed dose , are used to gauge long-term stochastic biological effects such as cancer incidence, but they are not designed to evaluate ARS. To help avoid confusion between these quantities, absorbed dose is measured in units of grays (in SI , unit symbol Gy ) or rad (in CGS ), while

7632-464: Is typically made based on a history of significant radiation exposure and suitable clinical findings. An absolute lymphocyte count can give a rough estimate of radiation exposure. Time from exposure to vomiting can also give estimates of exposure levels if they are less than 10 Gy (1000 rad). A guiding principle of radiation safety is as low as reasonably achievable (ALARA). This means try to avoid exposure as much as possible and includes

7776-431: Is unknowingly kept, sold, or stolen. The Goiânia accident is an example, where a forgotten radioactive source was taken from a hospital, resulting in the deaths of 4 people from ARS. Theft and attempted theft of radioactive material by clueless thieves has also led to lethal exposure in at least one incident. Exposure may also come from routine spaceflight and solar flares that result in radiation effects on earth in

7920-403: Is unlikely to cause significant damage to internal organs (although if contamination is ingested, inhaled or on the skin, and thus in close proximity to tissues and organs, the effect of these 'massive' particles may be catastrophic). The high penetrating power of gamma and neutron radiation , however, easily penetrates the skin and many thin shielding mechanisms to cause cellular degeneration in

8064-409: Is very damaging to DNA, while the latter events create clusters of DNA damage. This damage includes loss of nucleobases and breakage of the sugar-phosphate backbone that binds to the nucleobases. The DNA organization at the level of histones , nucleosomes , and chromatin also affects its susceptibility to radiation damage . Clustered damage, defined as at least two lesions within a helical turn,

8208-545: The 2011 Fukushima accident caused infant deaths in America, is " junk science ", as despite their papers being peer-reviewed, independent attempts to corroborate their results return findings that are not in agreement with what the organization suggests. The organization had earlier suggested the same thing occurred after the 1979 Three Mile Island accident, though the Atomic Energy Commission argued this

8352-556: The Crossroads underwater test, it was found that wet fallout must be immediately removed from ships by continuous water washdown (such as from the fire sprinkler system on the decks). Parts of the sea bottom may become fallout. After the Castle Bravo test, white dust—contaminated calcium oxide particles originating from pulverized and calcined corals —fell for several hours, causing beta burns and radiation exposure to

8496-553: The Nuclear Energy Agency (NEA) 's 2015 report: Occupational Radiation Protection in Severe Accident Management. The danger of radiation from fallout also decreases rapidly with time due in large part to the exponential decay of the individual radionuclides. A book by Cresson H. Kearny presents data showing that for the first few days after the explosion, the radiation dose rate is reduced by

8640-578: The Office of Civil Defense in the Department of Defense , provided guides to fallout protection in the 1960s, frequently in the form of booklets. These booklets provided information on how to best survive nuclear fallout. They also included instructions for various fallout shelters , whether for a family, a hospital, or a school shelter were provided. There were also instructions for how to create an improvised fallout shelter, and what to do to best increase

8784-525: The crater region is 30 grays per hour (Gy/h). Civilian dose rates in peacetime range from 30 to 100 μGy per year. For yields of up to 10 kt , prompt radiation is the dominant producer of casualties on the battlefield. Humans receiving an acute incapacitating dose (30 Gy) have their performance degraded almost immediately and become ineffective within several hours. However, they do not die until five to six days after exposure, assuming they do not receive any other injuries. Individuals receiving less than

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8928-427: The " Alarm Clock ", in that the nuclear device was a two-stage weapon: the first explosion was triggered by fission and the second more powerful explosion by fusion . The Sloika core consisted of a series of concentric spheres with alternating materials to help boost the explosive yield. In the years following World War II , eight countries have conducted nuclear tests with 2475 devices fired in 2120 tests. In 1963,

9072-503: The 1958 Cecil Kelley criticality accident , where the absorbed doses in Gy or rad are the only useful quantities, because of the targeted nature of the exposure to the body. Radiotherapy treatments are typically prescribed in terms of the local absorbed dose, which might be 60 Gy or higher. The dose is fractionated to about 2 Gy per day for curative treatment, which allows normal tissues to undergo repair , allowing them to tolerate

9216-538: The 20th century, most nations that have developed nuclear weapons had a staged test of them. Testing nuclear weapons can yield information about how the weapons work, as well as how the weapons behave under various conditions and how structures behave when subjected to a nuclear explosion. Additionally, nuclear testing has often been used as an indicator of scientific and military strength, and many tests have been overtly political in their intention; most nuclear weapons states publicly declared their nuclear status by means of

9360-615: The U.S. conducted hundreds of nuclear weapon tests. Atmospheric testing took place over the US mainland during this time and as a consequence scientists have been able to study the effect of nuclear fallout on the environment. Detonations conducted near the surface of the earth irradiated thousands of tons of soil. Of the material drawn into the atmosphere, portions of radioactive material will be carried by low altitude winds and deposited in surrounding areas as radioactive dust. The material intercepted by high altitude winds will continue to travel. When

9504-494: The United States Army Air Forces dropped a plutonium implosion-type device, code-named "Fat Man", on the city of Nagasaki . It killed 39,000 people, including 27,778 Japanese munitions employees, 2,000 Korean slave laborers, and 150 Japanese combatants. In total, around 109,000 people were killed in these bombings. Nuclear weapons are largely seen as a 'deterrent' by most governments; the sheer scale of

9648-596: The United States, Soviet Union , and United Kingdom signed the Limited Test Ban Treaty , pledging to refrain from testing nuclear weapons in the atmosphere, underwater, or in outer space. The treaty permitted underground tests. Many other non-nuclear nations acceded to the Treaty following its entry into force; however, France and China (both nuclear weapons states) have not. The primary application to date has been military (i.e. nuclear weapons), and

9792-442: The above-ground nuclear weapons testing that created the greatest amounts of atmospheric nuclear fallout. Some considered the baby tooth survey a "campaign [that] effectively employed a variety of media advocacy strategies" to alarm the public and "galvanized" support against atmospheric nuclear testing,, and putting an end to such testing was commonly viewed as a positive outcome for a myriad of reasons. The survey could not show at

9936-421: The air, called an air burst , produces less fallout than a comparable explosion near the ground. A nuclear explosion in which the fireball touches the ground pulls soil and other materials into the cloud and neutron activates it before it falls back to the ground. An air burst produces a relatively small amount of the highly radioactive heavy metal components of the device itself. In case of water surface bursts,

10080-412: The atmosphere is largely transparent. This event is also known as "flash", where radiant heat and light are bombarded into any given victim's exposed skin, causing radiation burns. Death is highly likely, and radiation poisoning is almost certain if one is caught in the open with no terrain or building masking-effects within a radius of 0–3 km from a 1 megaton airburst. The 50% chance of death from

10224-646: The atmosphere to cause the planet to cool and cause crops, animals, and agriculture to disappear across the globe—an effect named nuclear winter . The first manmade nuclear explosion occurred on July 16, 1945, at 5:50 am on the Trinity test site near Alamogordo, New Mexico , in the United States , an area now known as the White Sands Missile Range . The event involved the full-scale testing of an implosion-type fission atomic bomb . In

10368-409: The atmosphere, outer space, and under water. The dominant effect of a nuclear weapon (the blast and thermal radiation) are the same physical damage mechanisms as conventional explosives , but the energy produced by a nuclear explosive is millions of times more per gram and the temperatures reached are in the tens of megakelvin . Nuclear weapons are quite different from conventional weapons because of

10512-414: The base surge typically contains only about 10% of the total bomb debris in a subsurface burst, it can create larger radiation doses than fallout near the detonation, because it arrives sooner than fallout, before much radioactive decay has occurred. Meteorological conditions greatly influence fallout, particularly local fallout. Atmospheric winds are able to bring fallout over large areas. For example, as

10656-519: The biosphere. Fallout alters the quality of our atmosphere, soil, and water and causes species to go extinct. During the Cold War , the governments of the U.S., the USSR, Great Britain, and China attempted to educate their citizens about surviving a nuclear attack by providing procedures on minimizing short-term exposure to fallout. This effort commonly became known as Civil Defense . Fallout protection

10800-407: The blast and thermal effects, particularly in the case of high yield surface detonations. The ground track of fallout from an explosion depends on the weather from the time of detonation onward. In stronger winds, fallout travels faster but takes the same time to descend, so although it covers a larger path, it is more spread out or diluted. Thus, the width of the fallout pattern for any given dose rate

10944-548: The blast extends out to ~8 km from a 1 megaton atmospheric explosion. Scientific testing on humans within the United States occurred extensively throughout the atomic age. Experiments took place on a range of subjects including, but not limited to; the disabled, children, soldiers, and incarcerated persons, with the level of understanding and consent given by subjects varying from complete to none. Since 1997 there have been requirements for patients to give informed consent, and to be notified if experiments were classified. Across

11088-560: The body are now understood to be more important. David Walsh first established the symptoms of radiation sickness in 1897. Ingestion of radioactive materials caused many radiation-induced cancers in the 1930s, but no one was exposed to high enough doses at high enough rates to bring on ARS. The atomic bombings of Hiroshima and Nagasaki resulted in high acute doses of radiation to a large number of Japanese people, allowing for greater insight into its symptoms and dangers. Red Cross Hospital Surgeon Terufumi Sasaki led intensive research into

11232-599: The body easily, so whole-body irradiation generally causes ARS before skin effects are evident. Local gamma irradiation can cause skin effects without any sickness. In the early twentieth century, radiographers would commonly calibrate their machines by irradiating their own hands and measuring the time to onset of erythema . Accidental exposure may be the result of a criticality or radiotherapy accident. There have been numerous criticality accidents dating back to atomic testing during World War II, while computer-controlled radiation therapy machines such as Therac-25 played

11376-502: The bone marrow stored in the pelvic area as well as other radio sensitive organs in the abdominal region without hindering functional mobility. Where radioactive contamination is present, an elastomeric respirator , dust mask , or good hygiene practices may offer protection, depending on the nature of the contaminant. Potassium iodide (KI) tablets can reduce the risk of cancer in some situations due to slower uptake of ambient radioiodine. Although this does not protect any organ other than

11520-448: The cells in the digestive system ( microvilli , which form part of the wall of the intestines ) is fatal. Treatment usually involves supportive care with possible symptomatic measures employed. The former involves the possible use of antibiotics , blood products , colony stimulating factors , and stem cell transplant . There is a direct relationship between the degree of the neutropenia that emerges after exposure to radiation and

11664-403: The controversial but commonly applied linear no-threshold model , any exposure to ionizing radiation, even at doses too low to produce any symptoms of radiation sickness, can induce cancer due to cellular and genetic damage. The probability of developing cancer is a linear function with respect to the effective radiation dose . Radiation cancer may occur after ionizing radiation exposure following

11808-422: The destruction caused by nuclear weapons has discouraged their use in warfare. Since the Trinity test and excluding combat use, countries with nuclear weapons have detonated roughly 1,700 nuclear explosions, all but six as tests. Of these, six were peaceful nuclear explosions . Nuclear tests are experiments carried out to determine the effectiveness, yield and explosive capability of nuclear weapons. Throughout

11952-515: The downwind hot spot. Snow and rain , especially if they come from considerable heights, accelerate local fallout. Under special meteorological conditions, such as a local rain shower that originates above the radioactive cloud, limited areas of heavy contamination just downwind of a nuclear blast may be formed. A wide range of biological changes may follow the irradiation of animals. These vary from rapid death following high doses of penetrating whole-body radiation, to essentially normal lives for

12096-553: The earth, the radioactivity is very much decreased. Also, after a year it is estimated that a sizable quantity of fission products move from the northern to the southern stratosphere. The intermediate time scale is between 1 and 30 days, with long term fallout occurring after that. Examples of both intermediate and long term fallout occurred after the 1986 Chernobyl accident , which contaminated over 20,000 km (7,700 sq mi) of land in Ukraine and Belarus . The main fuel of

12240-480: The effects on humans subjected to the atomic bombings of Hiroshima and Nagasaki , the indigenous peoples of the Marshall Islands subjected to the Castle Bravo thermonuclear bomb, animal studies and lab experiment accidents, have been compiled by the U.S. Department of Defense . A person who was less than 1 mile (1.6 km) from the atomic bomb Little Boy 's hypocenter at Hiroshima, Japan,

12384-406: The entire body from high energy gamma radiation is optimal, but the required mass to provide adequate attenuation makes functional movement nearly impossible. In the event of a radiation catastrophe, medical and security personnel need mobile protection equipment in order to safely assist in containment, evacuation, and many other necessary public safety objectives. Research has been done exploring

12528-449: The environment. Dust, smoke, and radioactive particles will fall hundreds of kilometers downwind of the explosion point and pollute surface water supplies. Iodine-131 would be the dominant fission product within the first few weeks, and in the months following the dominant fission product would be strontium-90 . These fission products would remain in the fallout dust, resulting in rivers, lakes, sediments, and soils being contaminated with

12672-429: The event of a nuclear fallout. Over time the groundwater could become contaminated with fallout particles, and would remain contaminated for over 10 years after a nuclear engagement. It would take hundreds or thousands of years for an aquifer to become completely pure. Groundwater would still be safer than surface water supplies and would need to be consumed in smaller doses. Long term, cesium-137 and strontium-90 would be

12816-421: The explosions will eject small particles from the Earth's surface into the atmosphere as well as nuclear particles. It's also assumed that fires will break out and become widespread, similar to what happened at Hiroshima and Nagasaki during the end of WWII, which will cause soot and other harmful particles to also be introduced into the atmosphere. Once these harmful particles are lofted, strong upper-level winds in

12960-403: The exposed tissue. As seen at Chernobyl , when skin is irradiated with high energy beta particles , moist desquamation (peeling of skin) and similar early effects can heal, only to be followed by the collapse of the dermal vascular system after two months, resulting in the loss of the full thickness of the exposed skin. Another example of skin loss caused by high-level exposure of radiation

13104-403: The exposure measured in air. A deposit of 1 joule per kilogram has the unit of 1 gray (Gy). For 1 MeV energy gamma rays, an exposure of 1 röntgen in air produces a dose of about 0.01 gray (1 centigray, cGy) in water or surface tissue. Because of shielding by the tissue surrounding the bones, the bone marrow only receives about 0.67 cGy when the air exposure is 1 röntgen and the surface skin dose

13248-488: The fallout would linger in soil, plants, and food chains for years. Marine food chains are more vulnerable to the nuclear fallout and the effects of soot in the atmosphere. Fallout radionuclides' detriment in the human food chain is apparent in the lichen-caribou-eskimo studies in Alaska. The primary effect on humans observed was thyroid dysfunction. The result of a nuclear fallout is incredibly detrimental to human survival and

13392-410: The fallout. Rural areas' water supplies would be slightly less polluted by fission particles in intermediate and long-term fallout than cities and suburban areas. Without additional contamination, the lakes, reservoirs, rivers, and runoff would be gradually less contaminated as water continued to flow through its system. Groundwater supplies such as aquifers would however remain unpolluted initially in

13536-429: The feasibility of partial body shielding, a radiation protection strategy that provides adequate attenuation to only the most radio-sensitive organs and tissues inside the body. Irreversible stem cell damage in the bone marrow is the first life-threatening effect of intense radiation exposure and therefore one of the most important bodily elements to protect. Due to the regenerative property of hematopoietic stem cells , it

13680-476: The fireball. These materials are limited to the original mass of the device, but include radioisotopes with long lives. When the nuclear fireball does not reach the ground, this is the only fallout produced. Its amount can be estimated from the fission-fusion design and yield of the weapon. After the detonation of a weapon at or above the fallout-free altitude (an air burst ), fission products, un-fissioned nuclear material, and weapon residues vaporized by

13824-459: The fires would create enough soot into the atmosphere to block sunlight, lowering global temperatures by more than one degree Celsius. The result would have the potential of creating widespread food insecurity (nuclear famine). Precipitation across the globe would be disrupted as a result. If enough soot was introduced in the upper atmosphere the planet's ozone layer could potentially be depleted, affecting plant growth and human health. Radiation from

13968-438: The form of solar storms . During spaceflight, astronauts are exposed to both galactic cosmic radiation (GCR) and solar particle event (SPE) radiation. The exposure particularly occurs during flights beyond low Earth orbit (LEO). Evidence indicates past SPE radiation levels that would have been lethal for unprotected astronauts. GCR levels that might lead to acute radiation poisoning are less well understood. The latter cause

14112-435: The form of nuclear fallout. The main health effect of nuclear fallout is cancer and birth defects because radiation causes changes in cells that can either kill or make them abnormal. Any nuclear explosion (or nuclear war ) would have wide-ranging, long-term, catastrophic effects. Radioactive contamination would cause genetic mutations and cancer across many generations. Another potential devastating effect of nuclear war

14256-423: The hands of dangerous people persists, many scientists are working hard to find the best way to protect human organs from the harmful effects of high energy radiation. Acute radiation syndrome (ARS) is the most immediate risk to humans when exposed to ionizing radiation in dosages greater than around 0.1  Gy/hr . Radiation in the low energy spectrum ( alpha and beta radiation ) with minimal penetrating power

14400-426: The heat of the fireball condense into a suspension of particles 10  nm to 20  μm in diameter. This size of particulate matter , lifted to the stratosphere , may take months or years to settle, and may do so anywhere in the world. Its radioactive characteristics increase the statistical cancer risk, with up to 2.4 million people having died by 2020 from the measurable elevated atmospheric radioactivity after

14544-433: The high radiation levels at north Rongelap to a downwind hot spot caused by the large amount of radioactivity carried on fallout particles of about 50–100 micrometres size. After Bravo , it was discovered that fallout landing on the ocean disperses in the top water layer (above the thermocline at 100 m depth), and the land equivalent dose rate can be calculated by multiplying the ocean dose rate at two days after burst by

14688-476: The huge amount of explosive energy that they can put out and the different kinds of effects they make, like high temperatures and ionizing radiation. The devastating impact of the explosion does not stop after the initial blast, as with conventional explosives. A cloud of nuclear radiation travels from the hypocenter of the explosion, causing an impact to life forms even after the heat waves have ceased. The health effects on humans from nuclear explosions comes from

14832-422: The increased risk of developing infection. Since there are no controlled studies of therapeutic intervention in humans, most of the current recommendations are based on animal research. The treatment of established or suspected infection following exposure to radiation (characterized by neutropenia and fever) is similar to the one used for other febrile neutropenic patients. However, important differences between

14976-518: The individuals did not receive other injuries or medical treatment. In the 1950s, the LD 50 for gamma rays was set at 3.5 Gy, while under more dire conditions of war (a bad diet, little medical care, poor nursing) the LD 50 was 2.5 Gy (250 rad). There have been few documented cases of survival beyond 6 Gy. One person at Chernobyl survived a dose of more than 10 Gy, but many of the persons exposed there were not uniformly exposed over their entire body. If

15120-478: The inhabitants of the nearby atolls and the crew of the Daigo Fukuryū Maru fishing boat. The scientists called the fallout Bikini snow . For subsurface bursts, there is an additional phenomenon present called " base surge ". The base surge is a cloud that rolls outward from the bottom of the subsiding column, which is caused by an excessive density of dust or water droplets in the air. For underwater bursts,

15264-458: The initial shockwave, the radiation exposure, and the fallout. The initial shockwave and radiation exposure come from the immediate blast which has different effects on the health of humans depending on the distance from the center of the blast. The shockwave can rupture eardrums and lungs, can also throw people back, and cause buildings to collapse. Radiation exposure is delivered at the initial blast and can continue for an extended amount of time in

15408-460: The isolates causing sepsis. Because aerobic and facultative Gram-positive bacteria (mostly alpha-hemolytic streptococci ) cause sepsis in about a quarter of the victims, coverage for these organisms may also be needed. A standardized management plan for people with neutropenia and fever should be devised. Empirical regimens contain antibiotics broadly active against Gram-negative aerobic bacteria ( quinolones : i.e., ciprofloxacin , levofloxacin ,

15552-553: The leading theories about the extinction of most dinosaur species, in that a large explosion ejected small particulate matter into the atmosphere and resulted in a global catastrophe characterized by cooler temperatures, acid rain, and the KT Layer . Acute radiation syndrome Acute radiation syndrome ( ARS ), also known as radiation sickness or radiation poisoning , is a collection of health effects that are caused by being exposed to high amounts of ionizing radiation in

15696-419: The loss of power and supply lines rupturing. Within the local nuclear fallout pattern suburban areas' water supplies would become extremely contaminated. At this point stored water would be the only safe water to use. All surface water within the fallout would be contaminated by falling fission products. Within the first few months of the nuclear exchange the nuclear fallout will continue to develop and detriment

15840-475: The major radionuclides affecting the fresh water supplies. The dangers of nuclear fallout do not stop at increased risks of cancer and radiation sickness, but also include the presence of radionuclides in human organs from food. A fallout event would leave fission particles in the soil for animals to consume, followed by humans. Radioactively contaminated milk, meat, fish, vegetables, grains and other food would all be dangerous because of fallout. From 1945 to 1967

15984-595: The mitotic cycle the cell is when the irradiation occurs. If the cell is in interphase , while it is still a single strand of chromatin, the damage will be replicated during the S1 phase of the cell cycle , and there will be a break on both chromosome arms; the damage then will be apparent in both daughter cells . If the irradiation occurs after replication, only one arm will bear the damage; this damage will be apparent in only one daughter cell. A damaged chromosome may cyclize, binding to another chromosome, or to itself. Diagnosis

16128-538: The only instances in history of nuclear weapons being used as an act of war. On August 29, 1949, the USSR became the second country to successfully test a nuclear weapon. RDS-1, dubbed "First Lightning" by the Soviets and "Joe-1" by the US, produced a 20 kiloton explosion and was essentially a copy of the American Fat Man plutonium implosion design. The United States' first thermonuclear weapon, Ivy Mike ,

16272-558: The others are measured in sieverts (in SI, unit symbol Sv ) or rem (in CGS). 1 rad = 0.01 Gy and 1 rem = 0.01 Sv. In most of the acute exposure scenarios that lead to radiation sickness, the bulk of the radiation is external whole-body gamma, in which case the absorbed, equivalent, and effective doses are all equal. There are exceptions, such as the Therac-25 accidents and

16416-695: The particles tend to be rather lighter and smaller, producing less local fallout but extending over a greater area. The particles contain mostly sea salts with some water; these can have a cloud seeding effect causing local rainout and areas of high local fallout. Fallout from a seawater burst is difficult to remove once it has soaked into porous surfaces because the fission products are present as metallic ions that chemically bond to many surfaces. Water and detergent washing effectively removes less than 50% of this chemically bonded activity from concrete or steel . Complete decontamination requires aggressive treatment like sandblasting , or acidic treatment. After

16560-462: The pattern of bacterial susceptibility and nosocomial infections in the affected area and medical center and the degree of neutropenia. Broad-spectrum empirical therapy (see below for choices) with high doses of one or more antibiotics should be initiated at the onset of fever. These antimicrobials should be directed at the eradication of Gram-negative aerobic bacilli (i.e., Enterobacteriaceae , Pseudomonas ) that account for more than three quarters of

16704-564: The pelvic region, which contains enough regenerative stem cells to repopulate the body with unaffected bone marrow. More information on bone marrow shielding can be found in the Health Physics Radiation Safety Journal article Selective Shielding of Bone Marrow: An Approach to Protecting Humans from External Gamma Radiation , or in the Organisation for Economic Co-operation and Development (OECD) and

16848-523: The project collected over 300,000 teeth from children of various ages before the project was ended in 1970. Preliminary results of the Baby Tooth Survey were published in the November 24, 1961, edition of the journal Science , and showed that levels of strontium-90 had risen steadily in children born in the 1950s, with those born later showing the most pronounced increases. The results of

16992-429: The radiation dose. This is not always the case, however; care should be taken when constructing shielding for a specific purpose. For example, although high atomic number materials are very effective in shielding photons , using them to shield beta particles may cause higher radiation exposure due to the production of bremsstrahlung x-rays, and hence low atomic number materials are recommended. Also, using material with

17136-687: The reactor was uranium , and surrounding this was graphite, both of which were vaporized by the hydrogen explosion that destroyed the reactor and breached its containment. An estimated 31 people died within a few weeks after this happened, including two plant workers killed at the scene. Although residents were evacuated within 36 hours, people started to complain of vomiting, migraines and other major signs of radiation sickness . The officials of Ukraine had to close off an area with an 18-mile (30 km) radius. Long term effects included at least 6,000 cases of thyroid cancer , mainly among children. Fallout spread throughout Europe, with Northern Scandinavia receiving

17280-639: The remainder of explosions include the following: Two nuclear weapons have been deployed in combat—both by the United States against Japan in World War II. The first event occurred on the morning of 6 August 1945, when the United States Army Air Forces dropped a uranium gun-type device, code-named "Little Boy", on the city of Hiroshima , killing 70,000 people, including 20,000 Japanese combatants and 20,000 Korean slave laborers . The second event occurred three days later when

17424-414: The shielding material required to properly protect the entire body from high energy radiation would make functional movement essentially impossible. This has led scientists to begin researching the idea of partial body protection: a strategy inspired by hematopoietic stem cell transplantation (HSCT). The idea is to use enough shielding material to sufficiently protect the high concentration of bone marrow in

17568-461: The stem and cascade down the outside of the fireball in a downdraft even as the cloud rises, so fallout begins to arrive near ground zero within an hour. More than half the total bomb debris lands on the ground within about 24 hours as local fallout. Chemical properties of the elements in the fallout control the rate at which they are deposited on the ground. Less volatile elements deposit first. Severe local fallout contamination can extend far beyond

17712-500: The stem cells found in bone marrow. While full body shielding in a secure fallout shelter as described above is the most optimal form of radiation protection, it requires being locked in a very thick bunker for a significant amount of time. In the event of a nuclear catastrophe of any kind, it is imperative to have mobile protection equipment for medical and security personnel to perform necessary containment, evacuation, and any number of other important public safety objectives. The mass of

17856-490: The syndrome in the weeks and months following the Hiroshima and Nagasaki bombings. Sasaki and his team were able to monitor the effects of radiation in patients of varying proximities to the blast itself, leading to the establishment of three recorded stages of the syndrome. Within 25–30 days of the explosion, Sasaki noticed a sharp drop in white blood cell count and established this drop, along with symptoms of fever, as prognostic standards for ARS. Actress Midori Naka , who

18000-417: The thickness of a layer of a material sufficient to reduce gamma radiation exposure by 50%. Halving thicknesses of common materials include: 1 cm (0.4 inch) of lead, 6 cm (2.4 inches) of concrete, 9 cm (3.6 inches) of packed earth or 150 m (500 ft) of air. When multiple thicknesses are built, the shielding multiplies. A practical fallout shield is ten halving-thicknesses of

18144-457: The three components of time, distance, and shielding. The longer that humans are subjected to radiation the larger the dose will be. The advice in the nuclear war manual entitled Nuclear War Survival Skills published by Cresson Kearny in the U.S. was that if one needed to leave the shelter then this should be done as rapidly as possible to minimize exposure. In chapter 12, he states that "[q]uickly putting or dumping wastes outside

18288-469: The thunderstorm. Whenever individuals remain in a radiologically contaminated area, such contamination leads to an immediate external radiation exposure as well as a possible later internal hazard from inhalation and ingestion of radiocontaminants, such as the rather short-lived iodine-131 , which is accumulated in the thyroid . There are two main considerations for the location of an explosion: height and surface composition. A nuclear weapon detonated in

18432-458: The thyroid gland, their effectiveness is still highly dependent on the time of ingestion, which would protect the gland for the duration of a twenty-four-hour period. They do not prevent ARS as they provide no shielding from other environmental radionuclides. If an intentional dose is broken up into a number of smaller doses, with time allowed for recovery between irradiations, the same total dose causes less cell death . Even without interruptions,

18576-514: The time, nor in the decades that have elapsed, that the levels of global strontium-90 or fallout in general, were life-threatening, primarily because "50 times the strontium-90 from before nuclear testing" is a minuscule number, and multiplication of minuscule numbers results in only a slightly larger minuscule number. Moreover, the Radiation and Public Health Project that currently retains the teeth has had their stance and publications criticized:

18720-611: The tissue showing the syndrome itself be exposed (e.g., gastrointestinal syndrome is not seen if the stomach and intestines are not exposed to radiation). Some areas affected are: Early symptoms of ARS typically include nausea, vomiting, headaches, fatigue, fever , and a short period of skin reddening . These symptoms may occur at radiation doses as low as 0.35 grays (35 rad). These symptoms are common to many illnesses, and may not, by themselves, indicate acute radiation sickness. A similar table and description of symptoms (given in rems , where 100 rem = 1 Sv ), derived from data from

18864-400: The troposphere can transport them thousands of kilometers and can end up transporting nuclear fallout and also alter the Earth's radiation budget. Once enough small particles are in the atmosphere, they can act as cloud condensation nuclei which will cause global cloud coverage to increase which in turn blocks incoming solar insolation and starts a global cooling period. This is not unlike one of

19008-410: The two conditions exist. Individuals that develop neutropenia after exposure to radiation are also susceptible to irradiation damage in other tissues, such as the gastrointestinal tract, lungs and central nervous system. These patients may require therapeutic interventions not needed in other types of neutropenic patients. The response of irradiated animals to antimicrobial therapy can be unpredictable, as

19152-438: The visible surge is, in effect, a cloud of liquid (usually water) droplets with the property of flowing almost as if it were a homogeneous fluid. After the water evaporates, an invisible base surge of small radioactive particles may persist. For subsurface land bursts, the surge is made up of small solid particles, but it still behaves like a fluid . A soil earth medium favors base surge formation in an underground burst. Although

19296-438: The weather, and whether they consumed contaminated milk, vegetables or fruit. Exposure can be on an intermediate time scale or long term. The intermediate time scale results from fallout that has been put into the troposphere and ejected by precipitation during the first month. Long-term fallout can sometimes occur from deposition of tiny particles carried in the stratosphere. By the time that stratospheric fallout has begun to reach

19440-663: The widespread nuclear weapons testing of the 1950s, peaking in 1963 (the Bomb pulse ). Levels reached about 0.15  mSv per year worldwide, or about 7% of average background radiation dose from all sources, and has slowly decreased since, with natural background radiation levels being around 1 mSv . Radioactive fallout has occurred around the world; for example, people have been exposed to iodine-131 from atmospheric nuclear testing. Fallout accumulates on vegetation, including fruits and vegetables. Starting from 1951 people may have gotten exposure, depending on whether they were outside,

19584-638: The world, the Soviet nuclear program involved human experiments on a large scale, which is still kept secret by the Russian government and the Rosatom agency. The human experiments that fall under intentional ARS exclude those that involved long term exposure . Criminal activity has involved murder and attempted murder carried out through abrupt victim contact with a radioactive substance such as polonium or plutonium . The most commonly used predictor of ARS

19728-471: Was a research effort focused on detecting the presence of strontium-90 , a cancer-causing radioactive isotope created by the more than 400 atomic tests conducted above ground that is absorbed from water and dairy products into the bones and teeth given its chemical similarity to calcium . The team sent collection forms to schools in the St. Louis, Missouri area, hoping to gather 50,000 teeth each year. Ultimately,

19872-590: Was detonated on 1 November 1952 at Enewetak Atoll and yielded 10 Megatons of explosive force. The first thermonuclear weapon tested by the USSR, RDS-6s (Joe-4), was detonated on August 12, 1953, at the Semipalatinsk Test Site in Kazakhstan and yielded about 400 kilotons. RDS-6s' design, nicknamed the Sloika, was remarkably similar to a version designed for the U.S. by Edward Teller nicknamed

20016-461: Was estimated to have received a hand dose of 100 Gy over the course of his lifetime lost his hand because of radiation dermatitis . Most people become ill after an exposure to 1 Gy or more. Fetuses are often more vulnerable to radiation and may miscarry , especially in the first trimester . Because of the large amount of short-lived fission products, the activity and radiation levels of nuclear fallout decrease very quickly after being released; it

20160-446: Was evident in experimental studies where metronidazole and pefloxacin therapies were detrimental. Antimicrobials that reduce the number of the strict anaerobic component of the gut flora (i.e., metronidazole) generally should not be given because they may enhance systemic infection by aerobic or facultative bacteria , thus facilitating mortality after irradiation. An empirical regimen of antimicrobials should be chosen based on

20304-438: Was found among the later conceived children born to survivors of the nuclear detonations at Hiroshima and Nagasaki. The surviving women of Hiroshima and Nagasaki who could conceive and were exposed to substantial amounts of radiation went on and had children with no higher incidence of abnormalities than the Japanese average. The Baby Tooth Survey founded by the husband and wife team of physicians Eric Reiss and Louise Reiss ,

20448-399: Was found to have absorbed about 9.46 grays (Gy) of ionizing radiation. The doses at the hypocenters of the Hiroshima and Nagasaki atomic bombings were 240 and 290 Gy, respectively. Cutaneous radiation syndrome (CRS) refers to the skin symptoms of radiation exposure. Within a few hours after irradiation, a transient and inconsistent redness (associated with itching ) can occur. Then,

20592-817: Was present during the atomic bombing of Hiroshima, was the first incident of radiation poisoning to be extensively studied. Her death on 24 August 1945 was the first death ever to be officially certified as a result of ARS (or "Atomic bomb disease"). There are two major databases that track radiation accidents: The American ORISE REAC/TS and the European IRSN ACCIRAD. REAC/TS shows 417 accidents occurring between 1944 and 2000, causing about 3000 cases of ARS, of which 127 were fatal. ACCIRAD lists 580 accidents with 180 ARS fatalities for an almost identical period. The two deliberate bombings are not included in either database, nor are any possible radiation-induced cancers from low doses. The detailed accounting

20736-615: Was unfounded. The tooth survey, and the organization's new target of pushing for test bans with US nuclear electric power stations, is detailed and critically labelled as the " Tooth Fairy issue" by the Nuclear Regulatory Commission . In the event of a large-scale nuclear exchange, the effects would be drastic on the environment as well as directly to the human population. Within direct blast zones everything would be vaporized and destroyed. Cities damaged but not completely destroyed would lose their water system due to

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