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76-560: (Redirected from I-110 ) "I-110" redirects here. For the isotope of iodine (I-110 or I), see Iodine-110 . Interstate 110 may refer to: Interstate 110 (California) , a north–south freeway running through Los Angeles, California Interstate 110 (Florida) , a spur route in Pensacola, Florida Interstate 110 (Louisiana) , a spur route in Baton Rouge, Louisiana Interstate 110 (Mississippi) ,

152-823: A fission product , and decays to xenon-135 , which is a nuclear poison with the largest known thermal neutron cross section , which is a cause of multiple complications in the control of nuclear reactors . The process of buildup of xenon-135 from accumulated iodine-135 can temporarily preclude a shut-down reactor from restarting. This is known as xenon poisoning or "falling into an iodine pit ". Iodine fission-produced isotopes not discussed above (iodine-128, iodine-130, iodine-132, and iodine-133) have half-lives of several hours or minutes, rendering them almost useless in other applicable areas. Those mentioned are neutron-rich and undergo beta decay to isotopes of xenon. Iodine-128 (half-life 25 minutes) can decay to either tellurium-128 by electron capture or to xenon-128 by beta decay. It has

228-500: A specific radioactivity of 2.177 × 10  TBq/g . Colloquially, radioactive materials can be described as "hot," and non-radioactive materials can be described as "cold." There are instances in which cold iodide is administered to people in order to prevent the uptake of hot iodide by the thyroid gland. For example, blockade of thyroid iodine uptake with potassium iodide is used in nuclear medicine scintigraphy and therapy with some radioiodinated compounds that are not targeted to

304-820: A contamination hazard. Access to such areas is controlled by a variety of barrier techniques, sometimes involving changes of clothing and footwear as required. The contamination within a controlled area is normally regularly monitored. Radiological protection instrumentation (RPI) plays a key role in monitoring and detecting any potential contamination spread, and combinations of hand held survey instruments and permanently installed area monitors such as Airborne particulate monitors and area gamma monitors are often installed. Detection and measurement of surface contamination of personnel and plant are normally by Geiger counter , scintillation counter or proportional counter . Proportional counters and dual phosphor scintillation counters can discriminate between alpha and beta contamination, but

380-404: A discussion of environmental contamination by alpha emitters please see actinides in the environment . Nuclear fallout is the distribution of radioactive contamination by the 520 atmospheric nuclear explosions that took place from the 1950s to the 1980s. In nuclear accidents, a measure of the type and amount of radioactivity released, such as from a reactor containment failure, is known as

456-498: A groundwater tracer as indicator of nuclear waste dispersion into the natural environment. In a similar fashion, I was used in rainwater studies to track fission products following the Chernobyl disaster . In some ways, I is similar to Cl . It is a soluble halogen, exists mainly as a non-sorbing anion , and is produced by cosmogenic, thermonuclear, and in-situ reactions. In hydrologic studies, I concentrations are usually reported as

532-462: A half dozen are the most notable in applied sciences such as the life sciences and nuclear power, as detailed below. Mentions of radioiodine in health care contexts refer more often to iodine-131 than to other isotopes. Of the many isotopes of iodine, only two are typically used in a medical setting: iodine-123 and iodine-131. Since I has both a beta and gamma decay mode, it can be used for radiotherapy or for imaging. I, which has no beta activity,

608-444: A half-life less than seven hours, which is too short to be used in biology. Unavoidable in situ production of this isotope is important in nuclear reactor control, as it decays to Xe, the most powerful known neutron absorber , and the nuclide responsible for the so-called iodine pit phenomenon. In addition to commercial production, I (half-life 8 days) is one of the common radioactive fission products of nuclear fission , and

684-488: A low external risk due to the shielding effect of the top layers of skin. See the article on sievert for more information on how this is calculated. Radioactive contamination can be ingested into the human body if it is airborne or is taken in as contamination of food or drink, and will irradiate the body internally. The art and science of assessing internally generated radiation dose is Internal dosimetry . The biological effects of ingested radionuclides depend greatly on

760-420: A major contamination incident, all potential pathways of internal exposure should be considered. Successfully used on Harold McCluskey , chelation therapy and other treatments exist for internal radionuclide contamination. Cleaning up contamination results in radioactive waste unless the radioactive material can be returned to commercial use by reprocessing . In some cases of large areas of contamination,

836-582: A much lower-energy internal conversion electron (35.5 keV), which does relatively little damage due to its low energy, even though its emission is more common. The relatively low-energy gamma from I/ Te decay is poorly suited for imaging, but can still be seen, and this longer-lived isotope is necessary in tests that require several days of imaging, for example, fibrinogen scan imaging to detect blood clots. Both I and I emit copious low energy Auger electrons after their decay, but these do not cause serious damage (double-stranded DNA breaks) in cells, unless

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912-430: A particular inhalation hazard. Respirators with suitable air filters or completely self-contained suits with their own air supply can mitigate these dangers. Airborne contamination is measured by specialist radiological instruments that continuously pump the sampled air through a filter. Airborne particles accumulate on the filter and can be measured in a number of ways: Commonly a semiconductor radiation detection sensor

988-400: A risk of significant exposure to radioiodines from fission products no longer exists. Iodine-131 (the most common radioiodine contaminant in fallout) also decays relatively rapidly with a half-life of eight days, so that 99.95% of the original radioiodine has vanished after three months. Radioactive contamination Such contamination presents a hazard because the radioactive decay of

1064-580: A short half-life, the best course of action may be to simply allow the material to naturally decay . Longer-lived isotopes should be cleaned up and properly disposed of because even a very low level of radiation can be life-threatening when in long exposure to it. Facilities and physical locations that are deemed to be contaminated may be cordoned off by a health physicist and labeled "Contaminated area." Persons coming near such an area would typically require anti-contamination clothing ("anti-Cs"). High levels of contamination may pose major risks to people and

1140-422: A sign, shielded with bags of lead shot , or cordoned off with warning tape containing the radioactive trefoil symbol . The hazard from contamination is the emission of ionizing radiation. The principal radiations which will be encountered are alpha, beta and gamma, but these have quite different characteristics. They have widely differing penetrating powers and radiation effects, and the accompanying diagram shows

1216-448: A single nuclide. Most I derived radioactivity on Earth is man-made, an unwanted long-lived byproduct of early nuclear tests and nuclear fission accidents. All other iodine radioisotopes have half-lives less than 60 days, and four of these are used as tracers and therapeutic agents in medicine. These are I, I, I, and I. All industrial production of radioactive iodine isotopes involves these four useful radionuclides. The isotope I has

1292-591: A spur route in Biloxi, Mississippi Interstate 110 (Texas) , a spur route in El Paso, Texas The stub of the San Bernardino Freeway west of I-5, formerly designated as Interstate 110 and now legislatively part of I-10 [REDACTED] Topics referred to by the same term This disambiguation page lists articles about roads and streets with the same name. If an internal link led you here, you may wish to change

1368-614: A variety of causes. It may occur due to the release of radioactive gases, liquids or particles. For example, if a radionuclide used in nuclear medicine is spilled (accidentally or, as in the case of the Goiânia accident , through ignorance), the material could be spread by people as they walk around. Radioactive contamination may also be an inevitable result of certain processes, such as the release of radioactive xenon in nuclear fuel reprocessing . In cases that radioactive material cannot be contained, it may be diluted to safe concentrations. For

1444-471: Is Te. Iodine-124 as the iodide salt can be used to directly image the thyroid using positron emission tomography (PET). Iodine-124 can also be used as a PET radiotracer with a usefully longer half-life compared with fluorine-18 . In this use, the nuclide is chemically bonded to a pharmaceutical to form a positron-emitting radiopharmaceutical, and injected into the body, where again it is imaged by PET scan. Iodine-129 ( I; half-life 15.7 million years)

1520-431: Is a product of cosmic ray spallation on various isotopes of xenon in the atmosphere , in cosmic ray muon interaction with tellurium-130, and also uranium and plutonium fission, both in subsurface rocks and nuclear reactors. Artificial nuclear processes, in particular nuclear fuel reprocessing and atmospheric nuclear weapons tests, have now swamped the natural signal for this isotope. Nevertheless, it now serves as

1596-685: Is a useful comparative guide for selecting the correct technology for the contamination type. The UK NPL publishes a guide on the alarm levels to be used with instruments for checking personnel exiting controlled areas in which contamination may be encountered. Surface contamination is usually expressed in units of radioactivity per unit of area for alpha or beta emitters. For SI , this is becquerels per square meter (or Bq/m ). Other units such as picoCuries per 100 cm or disintegrations per minute per square centimeter (1 dpm/cm = 167 Bq/m ) may be used. The air can be contaminated with radioactive isotopes in particulate form, which poses

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1672-405: Is administered either intravenously or orally following a diagnostic scan. This procedure may also be used, with higher doses of radio-iodine, to treat patients with thyroid cancer . The I is taken up into thyroid tissue and concentrated there. The beta particles emitted by the radioisotope destroys the associated thyroid tissue with little damage to surrounding tissues (more than 2.0 mm from

1748-448: Is encapsulated in titanium seeds and implanted in the area of the tumor, where it remains. The low energy of the gamma spectrum in this case limits radiation damage to tissues far from the implanted capsule. Iodine-125, due to its suitable longer half-life and less penetrating gamma spectrum, is also often preferred for laboratory tests that rely on iodine as a tracer that is counted by a gamma counter , such as in radioimmunoassaying . I

1824-434: Is encountered with naturally generated radon gas which can affect instruments that are set to detect contamination close to normal background levels and can cause false alarms. Because of this skill is required by the operator of radiological survey equipment to differentiate between background radiation and the radiation which emanates from contamination. Naturally occurring radioactive materials (NORM) can be brought to

1900-533: Is monitored by specialised installed exit control instruments such as frisk probes, hand contamination monitors and whole body exit monitors. These are used to check that persons exiting controlled areas do not carry contamination on their bodies or clothes. In the United Kingdom , HSE has issued a user guidance note on selecting the correct portable radiation measurement instrument for the application concerned. This covers all radiation instrument technologies and

1976-552: Is more suited for routine nuclear medicine imaging of the thyroid and other medical processes and less damaging internally to the patient. There are some situations in which iodine-124 and iodine-125 are also used in medicine. Due to preferential uptake of iodine by the thyroid, radioiodine is extensively used in imaging of and, in the case of I, destroying dysfunctional thyroid tissues. Other types of tissue selectively take up certain iodine-131-containing tissue-targeting and killing radiopharmaceutical agents (such as MIBG ). Iodine-125

2052-737: Is not sequestered by thyroid gland and inadvertently administer a radiological dose to that tissue. Potassium iodide has been distributed to populations exposed to nuclear fission accidents such as the Chernobyl disaster . The iodide solution SSKI , a s aturated s olution of potassium ( K ) i odide in water, has been used to block absorption of the radioiodine (it has no effect on other radioisotopes from fission). Tablets containing potassium iodide are now also manufactured and stocked in central disaster sites by some governments for this purpose. In theory, many harmful late-cancer effects of nuclear fallout might be prevented in this way, since an excess of thyroid cancers, presumably due to radioiodine uptake,

2128-405: Is stable. Iodine is thus a monoisotopic element . Its longest-lived radioactive isotope , I, has a half-life of 16.14 million years, which is far too short for it to exist as a primordial nuclide . Cosmogenic sources of I produce very tiny quantities of it that are too small to affect atomic weight measurements; iodine is thus also a mononuclidic element —one that is found in nature only as

2204-421: Is the only other iodine radioisotope used in radiation therapy, but only as an implanted capsule in brachytherapy , where the isotope never has a chance to be released for chemical interaction with the body's tissues. The gamma-emitting isotopes iodine-123 (half-life 13 hours), and (less commonly) the longer-lived and less energetic iodine-125 (half-life 59 days) are used as nuclear imaging tracers to evaluate

2280-571: Is the only proven radioisotope contamination effect after a fission accident, or from contamination by fallout from an atomic bomb (prompt radiation from the bomb also causes other cancers, such as leukemias, directly). Taking large amounts of iodide saturates thyroid receptors and prevents uptake of most radioactive iodine-131 that may be present from fission product exposure (although it does not protect from other radioisotopes, nor from any other form of direct radiation). The protective effect of KI lasts approximately 24 hours, so must be dosed daily until

2356-416: Is thus produced inadvertently in very large amounts inside nuclear reactors . Due to its volatility, short half-life, and high abundance in fission products, I (along with the short-lived iodine isotope I, which is produced from the decay of Te with a half-life of 3 days) is responsible for the largest part of radioactive contamination during the first week after accidental environmental contamination from

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2432-400: Is used as the radiolabel in investigating which ligands go to which plant pattern recognition receptors (PRRs). Iodine-124 is a proton-rich isotope of iodine with a half-life of 4.18 days. Its modes of decay are: 74.4% electron capture, 25.6% positron emission. I decays to Te. Iodine-124 can be made by numerous nuclear reactions via a cyclotron . The most common starting material used

2508-449: Is used that can also provide spectrographic information on the contamination being collected. A particular problem with airborne contamination monitors designed to detect alpha particles is that naturally occurring radon can be quite prevalent and may appear as contamination when low contamination levels are being sought. Modern instruments consequently have "radon compensation" to overcome this effect. Radioactive contamination can enter

2584-433: The Chernobyl disaster ) However, these epidemiological effects are seen primarily in children, and treatment of adults and children with therapeutic I, and epidemiology of adults exposed to low-dose I has not demonstrated carcinogenicity. Iodine-135 is an isotope of iodine with a half-life of 6.6 hours. It is an important isotope from the viewpoint of nuclear reactor physics . It is produced in relatively large amounts as

2660-523: The Fukushima nuclear accident of March 2011 from as much land as possible so that some of the 110,000 displaced people can return. Stripping out the key radioisotope threatening health ( caesium-137 ) from low-level waste could also dramatically decrease the volume of waste requiring special disposal. A goal is to find techniques that might be able to strip out 80 to 95% of the caesium from contaminated soil and other materials, efficiently and without destroying

2736-670: The International Commission on Radiological Protection has published a guide: "Publication 111 – Application of the Commission's Recommendations to the Protection of People Living in Long-term Contaminated Areas after a Nuclear Accident or a Radiation Emergency". The hazards to people and the environment from radioactive contamination depend on the nature of the radioactive contaminant, the level of contamination, and

2812-430: The absorbed dose . When radioactive contamination is being measured or mapped in situ , any location that appears to be a point source of radiation is likely to be heavily contaminated. A highly contaminated location is colloquially referred to as a "hot spot." On a map of a contaminated place, hot spots may be labeled with their "on contact" dose rate in mSv/h. In a contaminated facility, hot spots may be marked with

2888-502: The radioactive waste from a nuclear power plant. Thus highly dosed iodine supplements (usually potassium iodide ) are given to the populace after nuclear accidents or explosions (and in some cases prior to any such incident as a civil defense mechanism) to reduce the uptake of radioactive iodine compounds by the thyroid before the highly radioactive isotopes have had time to decay. Radioisotopes of iodine are called radioactive iodine or radioiodine . Dozens exist, but about

2964-457: The thyroid gland takes up a large percentage of any iodine that enters the body. Large quantities of inhaled or ingested radioactive iodine may impair or destroy the thyroid, while other tissues are affected to a lesser extent. Radioactive iodine-131 is a common fission product ; it was a major component of the radioactivity released from the Chernobyl disaster , leading to nine fatal cases of pediatric thyroid cancer and hypothyroidism . On

3040-464: The Geiger counter cannot. Scintillation detectors are generally preferred for hand-held monitoring instruments and are designed with a large detection window to make monitoring of large areas faster. Geiger detectors tend to have small windows, which are more suited to small areas of contamination. The spread of contamination by personnel exiting controlled areas in which nuclear material is used or processed

3116-472: The U.S. Department of Energy (DOE) and the commercial nuclear industry for decades to minimize contamination on radioactive equipment and surfaces and fix contamination in place. "Contamination control products" is a broad term that includes fixatives, strippable coatings, and decontamination gels . A fixative product functions as a permanent coating to stabilize residual loose/transferable radioactive contamination by fixing it in place; this aids in preventing

Interstate 110 - Misplaced Pages Continue

3192-558: The activity, the biodistribution, and the removal rates of the radionuclide, which in turn depends on its chemical form, the particle size, and route of entry. Effects may also depend on the chemical toxicity of the deposited material, independent of its radioactivity. Some radionuclides may be generally distributed throughout the body and rapidly removed, as is the case with tritiated water . Some organs concentrate certain elements and hence radionuclide variants of those elements. This action may lead to much lower removal rates. For instance,

3268-485: The anatomic and physiologic function of the thyroid. Abnormal results may be caused by disorders such as Graves' disease or Hashimoto's thyroiditis . Both isotopes decay by electron capture (EC) to the corresponding tellurium nuclides, but in neither case are these the metastable nuclides Te and Te (which are of higher energy, and are not produced from radioiodine). Instead, the excited tellurium nuclides decay immediately (half-life too short to detect). Following EC,

3344-411: The area affected is generally referred to as "contaminated". There are a large number of techniques for containing radioactive materials so that it does not spread beyond the containment and become contaminated. In the case of liquids, this is by the use of high integrity tanks or containers, usually with a sump system so that leakage can be detected by radiometric or conventional instrumentation. Where

3420-442: The biosphere as it becomes incorporated into vegetation, soil, milk, animal tissue, etc. Excesses of stable Xe in meteorites have been shown to result from decay of "primordial" iodine-129 produced newly by the supernovas that created the dust and gas from which the solar system formed. This isotope has long decayed and is thus referred to as "extinct". Historically, I was the first extinct radionuclide to be identified as present in

3496-402: The body through ingestion , inhalation , absorption , or injection . This will result in a committed dose . For this reason, it is important to use personal protective equipment when working with radioactive materials. Radioactive contamination may also be ingested as the result of eating contaminated plants and animals or drinking contaminated water or milk from exposed animals. Following

3572-492: The case of fixed contamination, the radioactive material cannot by definition be spread, but its radiation is still measurable. In the case of free contamination, there is the hazard of contamination spread to other surfaces such as skin or clothing, or entrainment in the air. A concrete surface contaminated by radioactivity can be shaved to a specific depth, removing the contaminated material for disposal. For occupational workers, controlled areas are established where there may be

3648-402: The contaminants produces ionizing radiation (namely alpha , beta , gamma rays and free neutrons ). The degree of hazard is determined by the concentration of the contaminants, the energy of the radiation being emitted, the type of radiation, and the proximity of the contamination to organs of the body. It is important to be clear that the contamination gives rise to the radiation hazard, and

3724-407: The contamination may be mitigated by burying and covering the contaminated substances with concrete, soil, or rock to prevent further spread of the contamination to the environment. If a person's body is contaminated by ingestion or by injury and standard cleaning cannot reduce the contamination further, then the person may be permanently contaminated. Contamination control products have been used by

3800-458: The early Solar System . Its decay is the basis of the I-Xe iodine-xenon radiometric dating scheme, which covers the first 85 million years of Solar System evolution. Iodine-131 ( I ) is a beta-emitting isotope with a half-life of eight days, and comparatively energetic (190 keV average and 606 keV maximum energy) beta radiation, which penetrates 0.6 to 2.0 mm from

3876-458: The environment. Elements like uranium and thorium , and their decay products , are present in rock and soil. Potassium-40 , a primordial nuclide , makes up a small percentage of all potassium and is present in the human body. Other nuclides, like carbon-14 , which is present in all living organisms, are continuously created by cosmic rays . These levels of radioactivity pose little bit danger but can confuse measurement. A particular problem

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3952-475: The environment. People can be exposed to potentially lethal radiation levels, both externally and internally, from the spread of contamination following an accident (or a deliberate initiation ) involving large quantities of radioactive material. The biological effects of external exposure to radioactive contamination are generally the same as those from an external radiation source not involving radioactive materials, such as x-ray machines, and are dependent on

4028-419: The excited Te from I emits a high-speed 127 keV internal conversion electron (not a beta ray ) about 13% of the time, but this does little cellular damage due to the nuclide's short half-life and the relatively small fraction of such events. In the remainder of cases, a 159 keV gamma ray is emitted, which is well-suited for gamma imaging. Excited Te resulting from electron capture of I also emits

4104-450: The extent of the spread of contamination. Low levels of radioactive contamination pose little risk, but can still be detected by radiation instrumentation. If a survey or map is made of a contaminated area, random sampling locations may be labeled with their activity in becquerels or curies on contact. Low levels may be reported in counts per minute using a scintillation counter . In the case of low-level contamination by isotopes with

4180-675: The floor and any rags used to wipe up the spill. Cases of widespread radioactive contamination include the Bikini Atoll , the Rocky Flats Plant in Colorado, the area near the Fukushima Daiichi nuclear disaster , the area near the Chernobyl disaster , and the area near the Mayak disaster . The sources of radioactive pollution can be natural or man-made. Radioactive contamination can be due to

4256-478: The human body from an external or internal origin. This is due to radiation from contamination located outside the human body. The source can be in the vicinity of the body or can be on the skin surface. The level of health risk is dependent on duration and the type and strength of irradiation. Penetrating radiation such as gamma rays, X-rays, neutrons or beta particles pose the greatest risk from an external source. Low penetrating radiation such as alpha particles have

4332-529: The human body irradiate the tissues over time periods determined by their physical half-life and their biological retention within the body. Thus they may give rise to doses to body tissues for many months or years after the intake. The need to regulate exposures to radionuclides and the accumulation of radiation dose over extended periods of time has led to the definition of committed dose quantities". The ICRP further states "For internal exposure, committed effective doses are generally determined from an assessment of

4408-502: The intakes of radionuclides from bioassay measurements or other quantities (e.g., activity retained in the body or in daily excreta). The radiation dose is determined from the intake using recommended dose coefficients". The ICRP defines two dose quantities for individual committed dose: Committed equivalent dose , H T ( t ) is the time integral of the equivalent dose rate in a particular tissue or organ that will be received by an individual following intake of radioactive material into

4484-568: The interpretation of the results. The methodological and technical details of the design and operation of environmental radiation monitoring programmes and systems for different radionuclides, environmental media and types of facility are given in IAEA Safety Standards Series No. RS–G-1.8 and in IAEA Safety Reports Series No. 64. Radioactive contamination by definition emits ionizing radiation, which can irradiate

4560-506: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Interstate_110&oldid=1161043615 " Categories : Road disambiguation pages Interstate 10 Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Iodine-110 There are 40 known isotopes of iodine ( 53 I) from I to I; all undergo radioactive decay except I, which

4636-428: The loose/transferable contamination along with the product. The residual radioactive contamination on the surface is significantly reduced once the strippable coating is removed. Modern strippable coatings show high decontamination efficiency and can rival traditional mechanical and chemical decontamination methods. Decontamination gels work in much the same way as other strippable coatings. The results obtained through

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4712-439: The material is likely to become airborne, then extensive use is made of the glovebox , which is a common technique in hazardous laboratory and process operations in many industries. The gloveboxes are kept under slight negative pressure and the vent gas is filtered in high-efficiency filters, which are monitored by radiological instrumentation to ensure they are functioning correctly. A variety of radionuclides occur naturally in

4788-414: The nuclide is incorporated into a medication that accumulates in the nucleus, or into DNA (this is never the case is clinical medicine, but it has been seen in experimental animal models). Iodine-125 is also commonly used by radiation oncologists in low dose rate brachytherapy in the treatment of cancer at sites other than the thyroid, especially in prostate cancer . When I is used therapeutically, it

4864-724: The organic content in the soil. One being investigated is termed hydrothermal blasting. The caesium is broken away from soil particles and then precipitated with ferric ferricyanide ( Prussian blue ). It would be the only component of the waste requiring special burial sites. The aim is to get annual exposure from the contaminated environment down to one millisievert (mSv) above background. The most contaminated area where radiation doses are greater than 50 mSv/year must remain off-limits, but some areas that are currently less than 5 mSv/year may be decontaminated allowing 22,000 residents to return. To help protect people living in geographical areas which have been radioactively contaminated,

4940-489: The other hand, radioactive iodine is used in the diagnosis and treatment of many diseases of the thyroid precisely because of the thyroid's selective uptake of iodine. The radiation risk proposed by the International Commission on Radiological Protection (ICRP) predicts that an effective dose of one sievert (100 rem) carries a 5.5% chance of developing cancer. Such a risk is the sum of both internal and external radiation doses. The ICRP states "Radionuclides incorporated in

5016-401: The penetration of these radiations in simple terms. For an understanding of the different ionising effects of these radiations and the weighting factors applied, see the article on absorbed dose . Radiation monitoring involves the measurement of radiation dose or radionuclide contamination for reasons related to the assessment or control of exposure to radiation or radioactive substances, and

5092-464: The ratio of I to total I (which is virtually all I). As is the case with Cl/Cl, I/I ratios in nature are quite small, 10 to 10 (peak thermonuclear I/I during the 1960s and 1970s reached about 10 ). I differs from Cl in that its half-life is longer (15.7 vs. 0.301 million years), it is highly biophilic, and occurs in multiple ionic forms (commonly, I and IO 3 ), which have different chemical behaviors. This makes it fairly easy for I to enter

5168-402: The site of uptake. This beta radiation can be used for the destruction of thyroid nodules or hyperfunctioning thyroid tissue and for elimination of remaining thyroid tissue after surgery for the treatment of Graves' disease . The purpose of this therapy, which was first explored by Dr. Saul Hertz in 1941, is to destroy thyroid tissue that could not be removed surgically. In this procedure, I

5244-442: The source term. The United States Nuclear Regulatory Commission defines this as "Types and amounts of radioactive or hazardous material released to the environment following an accident." Contamination does not include residual radioactive material remaining at a site after the completion of decommissioning . Therefore, radioactive material in sealed and designated containers is not properly referred to as contamination, although

5320-454: The spread of contamination and reduces the possibility of the contamination becoming airborne, reducing workforce exposure and facilitating future deactivation and decommissioning (D&D) activities. Strippable coating products are loosely adhered to paint-like films and are used for their decontamination abilities. They are applied to surfaces with loose/transferable radioactive contamination and then, once dried, are peeled off, which removes

5396-506: The surface or concentrated by human activities such as mining, oil and gas extraction, and coal consumption. Radioactive contamination may exist on surfaces or in volumes of material or air, and specialized techniques are used to measure the levels of contamination by detection of the emitted radiation. Contamination monitoring depends entirely upon the correct and appropriate deployment and utilisation of radiation monitoring instruments. Surface contamination may either be fixed or "free". In

5472-462: The terms "radiation" and "contamination" are not interchangeable. The sources of radioactive pollution can be classified into two groups: natural and man-made. Following an atmospheric nuclear weapon discharge or a nuclear reactor containment breach, the air, soil, people, plants, and animals in the vicinity will become contaminated by nuclear fuel and fission products . A spilled vial of radioactive material like uranyl nitrate may contaminate

5548-450: The thyroid, such as iobenguane ( MIBG ), which is used to image or treat neural tissue tumors, or iodinated fibrinogen, which is used in fibrinogen scans to investigate clotting. These compounds contain iodine, but not in the iodide form. However, since they may be ultimately metabolized or break down to radioactive iodide, it is common to administer non-radioactive potassium iodide to insure that metabolites of these radiopharmaceuticals

5624-506: The tissues absorbing the iodine). Due to similar destruction, I is the iodine radioisotope used in other water-soluble iodine-labeled radiopharmaceuticals (such as MIBG ) used therapeutically to destroy tissues. The high energy beta radiation (up to 606 keV) from I causes it to be the most carcinogenic of the iodine isotopes. It is thought to cause the majority of excess thyroid cancers seen after nuclear fission contamination (such as bomb fallout or severe nuclear reactor accidents like

5700-403: The units of measurement might be the same. Containment is the primary way of preventing contamination from being released into the environment or coming into contact with or being ingested by humans. Being within the intended Containment differentiates radioactive material from radioactive contamination . When radioactive materials are concentrated to a detectable level outside a containment,

5776-468: The use of contamination control products are variable and depend on the type of substrate, the selected contamination control product, the contaminants, and the environmental conditions (e.g., temperature, humidity, etc.). [2] Some of the largest areas committed to be decontaminated are in the Fukushima Prefecture , Japan. The national government is under pressure to clean up radioactivity due to

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