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PubMed1996

Fetal radiation exposure is minimal after pelvimetry by modified digital radiography.

OBJECTIVE: Our purpose was to determine the maximal fetal exposure to radiation by use of thermoluminescent dosimeters when pelvic measurements were performed by standard or modified digital radiography. STUDY DESIGN: Digital radiography of the pelvis was performed according to a standard technique. Lithium fluoride thermoluminescent dosimeters were positioned on the patient's skin to quantitate the maximal amount of radiation exposure to the fetus. The standard technique often included a portion of fetal vertex. The axial view technique was modified to use an angle of inclination of 17 to 29 degrees relative to the vertical axis. RESULTS: Digital radiography was well tolerated and interpretable images were consistently obtained. The maximal dose to the fetal vertex by use of the standard digital axial slice was 465 mrad. By modifying the standard digital technique and using an angle of inclination of 17 to 29 degrees it was possible to obtain an axial section without including any portion of the fetal vertex. This reduced the maximal total dose to the fetal vertex to 55 mrad, which is less than the background radiation exposure to the fetus over a 9-month period from natural sources. CONCLUSION: Data reported indicate that total fetal radiation exposure is minimal after pelvimetry by digital radiography. Incorporating the modification of the angle for the axial slice, as reported here, resulted in a further significant decrease in fetal radiation exposure.

Female↗

PubMed1992

Effective dose values in bone mineral measurements by photon absorptiometry and computed tomography.

A high degree of uncertainty and irritation predominates in the assessment and comparison of radiation dose values resulting from measurements of bone mineral density of the lumbar spine by photon absorptiometry and X-ray computed tomography. The skin dose values which are usually given in the literature are of limited relevance because the size of the irradiated volumes, the relative sensitivity of the affected organs and the radiation energies are not taken into account. The concept of effective dose, sometimes called whole-body equivalent dose, has to be applied. A detailed analysis results in an effective dose value of about 1 microSv for absorptiometry and about 30 microSv for computed tomography when low kV and mAs values are used. Lateral localizer radiographs, which are necessary for slice selection in CT, mean an additional dose of 30 microSv. Lateral X-ray films of the spine which are frequently taken in combination with absorptiometry result in a dose of 700 microSv or more. The concept of effective dose, the basic data and assumptions used in its assessment and a comparison with other dose burdens (for example the natural background radiation, of typically 2400 microSv per year) are discussed in detail.

Absorptiometry, Photon↗

PubMed1977

Relations between Light Level, Sucrose Concentration, and Translocation of Carbon 11 in Zea mays Leaves.

The mechanism of carbon transport in Zea mays leaves was investigated using carbon 11 which is a short lived (half-life 20.4 min) positronemitting isotope. The gamma radiation produced on annihilation allows in vivo or nondestructive measurement of the isotope and the short half-life allows many measurements of translocation to be made on the same leaf within the same day.Carbon 11 produced by the (10)B (d,n)(11)C nuclear reaction was converted to (11)CO(2), fed to a leaf as a short pulse, and assimilated during photosynthesis. The progress of the radioactive pulse along the leaf in the phloem was monitored in several positions simultaneously with counters. The counters were NaI crystals with photomultipliers and the output was amplified, passed to single channel analyzers, and the counts accumulated for 20 seconds every 30 seconds. Corrections were made for the half-life and background radiation by computer, and the results were displayed on a high speed plotter. Information derived from the corrected data included the speed of translocation, the shape of the radioactive carbon pulse, and the influence of light and distance along the leaf on these parameters. The plants were kept under controlled environment conditions during all measurements.A speed was derived from the time displacement of the midpoint of the front of the pulse, measured at two positions along the leaf. This was an apparent mean speed of translocation because it averaged a variation in speed with distance, variation in speed between or within sieve tubes, and it averaged the mean speed of all of the particles in the pulse.A wide range of speeds of translocation from 0.25 to 11 cm min(-1) was observed but most of the variability was due to the variation in light available to the leaf. For example, the speed of translocation was proportional to the light level on either the whole plant or individual leaf. Shading of the leaf established that the light effect was not localized in either the feeding area or in the portion of the leaf on which the measurements were made. It was proposed that the speed was dependent on the proportion of the leaf in the light upstream from the last counter. The speed of translocation was relatively independent of the stage of growth of the plant, age of the leaf, and the time during the diurnal light cycle.Data obtained on the level of the reducing sugars, starch, and sucrose in the leaf were related to the speed of translocation. A biphasic relationship between speed and sucrose concentration in the leaf was established and the high speeds measured during experiments only occurred when sucrose concentrations in the leaf exceeded 8% of the dry weight.The shape of the pulse loaded into and translocated in the phloem was estimated from the half-width of the pulse. The half-width was primarily determined by loading phenomena which resulted in an increase in the half-width from 2 minutes when fed to the leaf to more than 40 minutes in the phloem. In many examples, the pulse continued to broaden with distance along the leaf from the fed region. The half-width was independent of the speed but highly dependent on the light level.

Journal Article↗

PubMed2001

Natural gamma-radiation in the Aeolian volcanic arc.

Pulse-height distributions of gamma-rays, obtained with a field NaI(Tl) scintillation spectrometer in numerous sites of the Lipari and Vulcano islands (Aeolian volcanic arc, Italy), were measured to determine the U, Th and K concentrations of the bedrock and the relative values of the air absorbed dose rate. U is spatially related to both Th and K and the Th/U ratio is on average 3.1-3.5. The magmatic evolution is reflected by the concentration of the three radioelements, as they are more abundant within the more felsic units of the volcanic series. The higher values of U (15.7-20.0 ppm) coincide with higher Th (48.3-65.9 ppm) and K (4.9-6.1%) concentrations associated with rhyolitic rocks of the third cycle (< 50 ky). The air absorbed dose rate varies from 20 to 470 nGy h(-1). The highest values (> 350 nGy h(-1)) are observed on outcrops of rhyolitic obsidian lava flows. The cosmic-ray contribution is also evaluated to estimate the total background radiation dose rate.

Journal Article↗

PubMed2004

Track-etched detectors for the dosimetry of the radiation of cosmic origin.

Cosmic rays contribute to the exposure on the Earth's surface as well as in its surroundings. At the surface and/or at aviation altitudes, there are mostly secondary particles created through the cosmic rays interaction in the atmosphere, which contribute to this type of exposure. Onboard a spacecraft, the exposure comes mostly from primary cosmic rays. Track-etched detectors (TED) are able to characterise both these types of exposure. The contribution of neutrons, of cosmic origin, on the Earth's surface was studied at altitudes from few hundreds to 3000 m using TED in a moderator sphere. The results obtained are compared with other data on this type of natural radiation background. The results of studies performed onboard aircraft and/or spacecraft are presented afterwards. We used TED-based neutron dosemeter, as well as a spectrometer of linear energy transfer based on a chemically etched TED. The results of studies performed onboard aircraft, as well as spacecraft, are presented and discussed, including an attempt to estimate a neutron component onboard the spacecraft. It was found that they correlate with the results of other independent investigations.

Aircraft↗

PubMed2005

Spectral discrimination of Cerenkov radiation in scintillating dosimeters.

Radiation therapy accelerators require highly accurate dose deposition and the output must be monitored frequently and regularly. Ionization chambers are the primary tool for this control, but their size, their high voltage needed, and the correction needed for electrons make them unsuitable for use during patient treatment. We have developed a small (1-mm-diam and 1-mm-long active part), flexible, and water-equivalent dosimeter. It is suitable for photon and electron beams without corrections, and performs on line dose measurements. This detector is based on only one scintillating fiber and a CCD camera. A new signal processing is used to remove the effect of Cerenkov radiation background, which only requires a preliminary calibration. Central-axis depth-dose distribution comparisons have been achieved with standard ionization chambers, over a range from 8 to 25 MV photons and from 6 to 21 MeV electrons in order to validate this calibration. Results show a very good agreement, with less than 1% difference between the two detectors.

Calibration↗

PubMed1999

Radiation dose to the patient and operator from a peripheral dual X-ray absorptiometry system.

Although peripheral dual X-ray absorptiometry (pDXA) scanners for measuring bone mineral density (BMD) in the forearm are known to produce an exceptionally low radiation dose to the patient, quantitative assessment of patient dose from pDXA procedures is important for reassuring patients about their safety. We have estimated the effective dose of radiation (ICRP-60) to the patient and also the scattered dose to the operator from a forearm BMD examination performed on a DTX-200 pDXA system (Osteometer Meditech, Hoersholm, Denmark). Measurements were performed using thermoluminescent dosimeters (TLD's) attached to the forearm phantom supplied by the manufacturer. The effective dose to a patient was estimated to be 0.1 microSv. At a distance of 1 m from the center of the forearm, the time-averaged scattered dose to the operator assuming scanning five patients per hour was measured to be <0.1 microSv/h. The dose rate over the outside surface of the DTX-200 in line with the primary X-ray beam was measured to be 1.4 microSv/h. These figures compare with a natural background radiation in the United Kingdom of 7 microSv/d. In conclusion the radiation doses from forearm pDXA to both patients and operator were found to be truly trivial.

Absorptiometry, Photon↗

PubMed2002

Hematologic consequences of exposure to ionizing radiation.

From the early 1900s, it has been known that ionizing radiation (IR) impairs hematopoiesis through a variety of mechanisms. IR exposure directly damages hematopoietic stem cells and alters the capacity of bone marrow stromal elements to support and/or maintain hematopoiesis in vivo and in vitro. Exposure to IR induces dose-dependent declines in circulating hematopoietic cells not only through reduced bone marrow production, but also by redistribution and apoptosis of mature formed elements of the blood. Recently, the importance of using lymphocyte depletion kinetics to provide a "crude" dose estimate has been emphasized, particularly in rapid assessment of large numbers of individuals who may be exposed to IR through acts of terrorism or by accident. A practical strategy to estimate radiation dose and triage victims based upon clinical symptomatology is presented. An explosion of knowledge has occurred regarding molecular and cellular pathways that trigger and mediate hematologic responses to IR. In addition to damaging DNA, IR alters gene expression and transcription, and interferes with intracellular and intercellular signaling pathways. The clinical expression of these disturbances may be the development of leukemia, the most significant hematologic complication of IR exposure among survivors of the atomic bomb detonations over Japan. Those at greatest risk for leukemia are individuals exposed during childhood. The association of leukemia with chronic, low-dose-rate exposure from nuclear power plant accidents and/or nuclear device testing has been more difficult to establish, due in part to lack of precision and sensitivity of methods to assess doses that approach background radiation dose. Nevertheless, multiple myeloma may be associated with chronic exposure, particularly in those exposed at older ages.

Cell Survival↗

PubMedDate not supplied

[Effect of chronic gamma irradiation on dehydrogenase activity in the tissues of root voles and their progeny dwelling in a habitat with increased radioactivity].

Chronic gamma-irradiation during 3.5 and 6 months (at a dose = rate of 46.2 pC/kg X c) of Microtus oeconomus living in conditions of normal and increased (by 50-100 times) gamma-radiation background, and of their progeny (the 1st, 2nd, 3d, and 4th generations) causes in homogenates of cardiac muscle, liver, and brain different changes in activity of succinate dehydrogenase (1.3.99.1, EC), pyruvate dehydrogenase (1.2.4.1, EC), and lactate dehydrogenase (1.1.1.27, EC) associated with the discordance of the processes of tissue respiration and glycolysis. The changes in dehydrogenases activity in Microtus oeconomus subjected to chronic irradiation were nearly the same as those found in their parents.

Aging↗

PubMed1997

A comparison of independently conducted dose assessments to determine compliance and resettlement options for the people of Rongelap Atoll.

Rongelap Island was the home of Marshallese people numbering less than 120 in 1954; 67 were on the island and severely exposed to radioactive fallout from an atomic weapons test in March of that year. Those resident on Rongelap were evacuated 50 h after the test, returned 3 y later, then voluntarily left their home island in 1985 due to their ongoing fear of radiation exposure from residual radioactive contamination. Following international negotiations in 1991, a Memorandum of Understanding (MOU) was signed in early 1992 between the Republic of the Marshall Islands Government, the Rongelap Atoll Local Government, the U.S. Department of Energy, and the U.S. Department of the Interior. In this MOU it was agreed that the Republic of the Marshall Islands, with the aid of the U.S. Department of Energy, would carry out independent dose assessments for the purpose of assisting and advising the Rongelap community on radiological issues related to a safe resettlement of Rongelap. The MOU enacted two action levels which were agreed to be used to establish whether mitigation should be considered as a condition for resettlement of Rongelap Island: (1) no individual should receive an annual dose in the future of 1 mSv or more, above that from natural background radiation, assuming that his/her diet consists of only locally produced foods, and (2) the total surface soil concentration of plutonium and other transuranic elements must be less than 629 Bq kg(-1) (averaged over the top 5 cm). Environmental radiological data and dietary information were collected over two years (1992-1993) for the purpose of predicting future potential doses to Rongelapese who might resettle. In 1994, four independent assessments were reported, including one from each of the following entities: Marshall Islands Nationwide Radiological Study; Lawrence Livermore National Laboratory; an independent advisor from the United Kingdom (MCT); and a committee of the National Research Council. All four assessments concluded that possibly more than 25% of the adult population could exceed the 1 mSv y(-1) dose level based on strict utilization of a local food diet. The purpose of this report is to summarize the methodology, assumptions, and findings from each of four assessments; to summarize the recommendations related to mitigation and resettlement options; to discuss unique programmatic aspects of the study; and to consider the implications of the findings to the future of the Rongelap people.

Adult↗

PubMed1998

Radiation dose from DXA scanning to reproductive tissues of females.

The objective of this study was to use an anatomically arrayed whole-body phantom to measure radiation exposure to the ovaries and uterus during standard dual-energy Xray absorptiometry (DXA) scanning. DXA instrument manufacturers' published entrance skin exposure is about 3 mR (0.77 microC/kg), which is equivalent to the radiation exposure received during a transcontinental plane trip. Nonetheless, since DXA scanning is used more frequently with very young females, the need for pregnancy testing has become an issue that requires attention and formulation of research guidelines. We attached thermoluminescent dosimeters (TLDs) to anatomically arrayed balloon models for ovaries and the uterus, and placed these in the appropriate sites within a small human skeleton along with appropriate amounts of aqueous and fat soft tissue equivalents. Whole-body scanning with a Hologic QDR-2000W was performed 10 times with the pencil beam mode and, using separate TLD detectors, 10 times with the fan beam mode. Overall, the average exposures at skin entrance were 0.89 mR (0.23 microC/kg) with doses for the ovaries of 0.52 mrad (5.2 microgy) and 0.59 mrad (5.9 microgy) for the uterus. These doses are equivalent to 2 d of ambient background radiation in central Pennsylvania or 1 h of flying at 39,000 ft. Although different DXA models by Hologic and DXA instruments by other manufacturers will have different radiation outputs, we believe that these low radiation levels do not require pregnancy testing or questioning of whether the scan subject might be pregnant.

Journal Article↗

PubMedDate not supplied

Calculated DNA damage from gadolinium Auger electrons and relation to dose distributions in a head phantom.

PURPOSE: To calculate the number of 157Gadolinium (157Gd) neutron capture induced DNA double strand breaks (DSB) in tumor cells resulting from epithermal neutron irradiation of a human head when the peak tissue dose is 10 Gy. To assess the lethality of these Gd induced DSB. MATRIALS AND METHODS: DNA single and double strand breaks from Auger electrons emitted during 157Gd(n,gamma) events were calculated using an atomistic model of B-DNA with higher-order structure. When combined with gadolinium neutron capture reaction rates and neutron and photon physical dose rates calculated from the radiation transport through a model of the human head with explicit tumors, peak tissue dose can be related to the number of Auger electron induced DSB in tumor cell DNA. The lethality of these DNA DSB were assessed through a comparison with incorporated 125I decay cell survival curves and second comparison with the number of DSB resulting from neutron and photon interactions. RESULTS: These calculations on a molecular scale (microscopic calculations) indicate that for incorporated 157Gd, each neutron capture reaction results in an average of 1.56 +/- 0.16 DNA single strand breaks (SSB) and 0.21 +/- 0.04 DBS in the immediate vicinity (approximately 40 nm) of the neutron capture. In an example case of Gd Neutron Capture Therapy (GdNCT), a 1 cm radius midline tumor, peak normal tissue dose of 10 Gy, and a tumor concentration of 1000 ppm Gd, result in a maximum of 140 +/- 27 DSBs per tumor cell. CONCLUSIONS: The number of DSB from the background radiation components is one order of magnitude lower than the Gd Auger electron induced DSB. The cell survival of mammalian cell lines with a similar amount of complex DSB induced from incorporated 125I decay yield one to two magnitudes of cell killing. These two points indicate that gadolinium auger electrons could significantly contribute to cell killing in GdNCT.

Brain Neoplasms↗

PubMedDate not supplied

[Morphological, cytogenetic and molecular biological characteristics of lung cancer in persons exposed for a long time to radionuclide radiation pollution in the Semipalatinsk region of Kazakhstan].

Surgical and biopsy material was used from 57 patients with lung carcinoma (LC): 17 patients (group I) lived close to testing area from the childhood to 1993 and were exposed to radiation at the year dose 0.1 ber. For comparison surgical and biopsy material from 40 patients (group 2) was taken who lived in the territories of Kazakhstan (10 patients) and Moscow (30 patients) with normal radiation background. The following features of LC were found in the groups in question: constant observation of dust particles and interstitial and focal fibrosis in tumours of various localization and histological type; prevailing small cell carcinoma as compared to other histological types; high frequency of nonsmall cell lung carcinoma; higher expression of IGFII, IGFBP1,2 and rare expression of IGFB3; proliferative activity followed by an increased expression of c-myc, bcl-2.

Air Pollution, Radioactive↗

PubMed2006

Alterations in gene expression in rat skin exposed to 56Fe ions and dietary vitamin A acetate.

The purpose of the present work was to examine gene expression patterns in rat skin exposed to a beam of (56)Fe ions, a surrogate for the high-energy, heavy-ion galactic radiation background, as a basis for obtaining a better understanding of the possible mechanism(s) behind the radioprotective activity of vitamin A. A 2 x 4-cm rectangle of dorsal rat skin was exposed to 1.01 GeV/nucleon (56)Fe ions generated by the Alternating Gradient Synchrotron at Brookhaven National Laboratory. Gene expression patterns were monitored in either the presence or absence of a 250-ppm dietary supplement of vitamin A acetate in powdered lab chow. Although vitamin A and other retinoids show anti-carcinogenic activity in several animal models, the underlying changes in gene expression have not been examined extensively. At either 1 or 7 day after irradiation, a 1-cm square of irradiated and control rat skin was excised and analyzed using the Affymetrix rat microarray (RG_U34A) system. Microarray responses were displayed and processed by GeneSpring 7.0 and GOTree software. At 1 day after 3 Gy of (56)Fe-ion irradiation, the expression of 110 genes was significantly up-regulated (P < = 0.05) in comparison to levels in control rat skin, while no genes were altered by the vitamin A acetate supplement alone. Combined with (56)Fe-ion radiation, the vitamin A acetate supplement blocked the expression of 88 (80%) of the 110 genes and eliminated 16 of 18 gene categories that were significantly altered (all increased) by the (56)Fe-ion radiation. Categories with large numbers of genes eliminated by the retinoid included response to stress, 33 genes; response to biotic stimulus, 38 genes; signal transduction, 35 genes; and regulation of cellular/physiological process, 40 genes. Even for immune response and response to biotic stimulus, the only two categories that remained significantly altered in the presence of the vitamin, the combined number of altered genes was reduced from 74 to 13. No significant alterations in gene expression were found at 7 days relative to the numbers in controls. The results indicate that at 1 day dietary vitamin A acetate strongly interfered with (56)Fe-ion-induced gene expression within the broad categories of stimulus- and stress-related genes, implying that the latter gene categories likely play a role in the radioprotective action of the vitamin.

Administration, Oral↗

PubMed2005

Simulation of secondary particle production and absorbed dose to tissue in light ion beams.

During radiation therapy with an ion beam, the production of secondary particles like neutrons, protons and heavier ions contribute to the dose delivered to tumour and healthy tissues outside the treated volume. Also, the secondary particles leaving the patient are of interest for radiation background around the ion-therapy facility. Calculations of secondary particle production and the dose absorbed by water, soft tissue and a multi-material phantom simulating the heterogeneous media of the patient body were performed for protons, helium, lithium and carbon ions in the energy range up to 400 MeV u(-1). The Monte Carlo code SHIELD-HIT for transport of protons and light ions in tissue-like media was used in these studies. The neutron ambient dose-equivalent, H*(10), was determined for neutrons leaving the water phantom irradiated with different light ion beams. The comparison of calculated secondary particle production in the water and PMMA phantoms irradiated with helium and carbon ions shows satisfactory agreement with experimental data.

Body Burden↗

PubMed1999

Unfiltered sulfur colloid and sentinel node biopsy for breast cancer: technical and kinetic considerations.

BACKGROUND: There are few clinical data on technical limitations and radiocolloid kinetics related to sentinel lymph node (SLN) biopsy for breast cancer. METHODS: In 70 clinical node-negative patients, unfiltered 99mTc sulfur-colloid was injected peritumorally and cutaneous hot spots were mapped with a gamma probe. SLN biopsy was performed followed by axillary lymph node dissection. Missed radioactive nodes (nodes not under hot spots) were removed from axillary lymph node dissection specimens and submitted separately. RESULTS: At least one hot spot was mapped in 69 patients (98%) and SLNs were retrieved in 62 (89%). No radiolabeled nodes were found in five (7%) and only nodes not under hot spots were retrieved in three patients (4%). Residual nodes not under hot spots were retrieved in 17 patients (24%) in whom at least one SLN specimen had been found. Diffuse radioactivity around the radiocolloid injection site impeded identification of all radiolabeled nodes during SLN biopsy, and was responsible for one of two false negatives (20 node-positive patients; false-negative rate 10%). Hot spot radioactivity, number of radiolabeled nodes, and nodal radioactivity did not change with time interval from radiocolloid injection to surgery (0.75-6.25 hours). CONCLUSIONS: Although SLN localization rate is high, intraparenchymal injection may predispose to failure of radiocolloid migration, failure to identify SLNs because of high radiation background, and false-negative outcomes. Alternative routes of radiocolloid administration should be explored.

Adult↗

PubMed1985

Indoor dose in Milano (Italy).

This work is related to the problem of providing a more careful evaluation of the population exposure to natural radiation background, and was carried out in connection with the ENEA programmes on the assessment of indoor exposure doses in Italy. A large number of works in recent years have pointed out the main contribution of the indoor dose to the natural dose received by the members of the general population, and the large contribution of radon daughter inhalation. Different building materials and techniques lead to different exposure doses. In Milano such materials can be quite different in kind (bricks, concrete, gypsum by-products, tile-stone, paving-tile, etc.) and origin (national and foreign). For this reason, a collection of indoor doses in Milano is not only complementary to analogous investigations carried out in other Countries of the European Communities, but the obtained information can be compared with other large European towns. As agreed, a large number of various dwellings in Milano were investigated to evaluate the external gamma-ray exposure rate, and measurements of indoor radon concentrations were performed for some of them. Various typical building materials used in Lombardia were also analysed by means of gamma-ray spectrometry.

Construction Materials↗

PubMed2003

Rapid identification and analysis of airborne plutonium using a combination of alpha spectroscopy and inductively coupled plasma mass spectrometry.

Recent wildland fires near two U.S. nuclear facilities point to a need to rapidly identify the presence of airborne plutonium during incidents involving the potential release of radioactive materials. Laboratory turn-around times also need to be shortened for critical samples collected in the earliest stages of radiological emergencies. This note discusses preliminary investigations designed to address both these problems. The methods under review are same day high-resolution alpha spectroscopy to screen air filter samples for the presence of plutonium and inductively coupled plasma mass spectrometry to perform sensitive plutonium analyses. Thus far, using modified alpha spectroscopy techniques, it has been possible to reliably identify the approximately 5.2 MeV emission of 239Pu on surrogate samples (air filters artificially spiked with plutonium after collection) even though the primary alpha-particle emissions of plutonium are, as expected, superimposed against a natural alpha radiation background dominated by short-lived radon and thoron progeny (approximately 6-9 MeV). Several processing methods were tested to prepare samples for analysis and shorten laboratory turn-around time. The most promising technique was acid-leaching of air filter samples using a commercial open-vessel microwave digestion system. Samples prepared in this way were analyzed by both alpha spectroscopy (as a thin-layer iron hydroxide co-precipitate) and inductively coupled plasma mass spectrometry. The detection levels achieved for 239Pu--approximately 1 mBq m(-3) for alpha spectroscopy screening, and, < 0.1 mBq m(-3) for inductively coupled plasma mass spectrometry analysis--are consistent with derived emergency response levels based on EPA's Protective Action Guides, and samples can be evaluated in 36 to 72 h. Further, if samples can be returned to a fixed-laboratory and processed immediately, results from mass spectrometry could be available in as little as 24 h. When fully implemented, these techniques have the potential to provide useful information and improved operational flexibility to emergency planners and first-responders during radiological emergencies.

Air Pollution, Radioactive↗