Measurements of the radioactivity of the cloud from the accident at Windscale Works (Sellafield, England) in October 1957: data submitted to the International Geophysical Year (IGY; July 1957-December 1958)

A fire in a nuclear reactor at Windscale Works (Sellafield, England) in October 1957 led to an uncontrolled aerial release of radionuclides. At the time of the accident air was sampled at various locations in Europe to monitor atmospheric pollution, and the opportunity was taken to measure the sampling filters for activity concentrations of iodine-131, caesium-137 and polonium-210 at the Harwell research establishment (United Kingdom); when it was not possible to perform measurements at Harwell, original measurement data were supplied. This programme of activity measurements was performed in the context of work by the Advisory Committee on Nuclear Radiation of the International Geophysical Year (IGY; July 1957-December 1958). The International Geophysical Year was an international programme of research into a comprehensive range of geophysical phenomena. The results of this measurement programme were originally reported in Harwell Memorandum AERE-M857 (1961) and this Harwell report is reproduced in this paper because of its historical interest and because it is no longer readily accessible to researchers.

Twenty five years of the National Academy of Medical Sciences of Ukraine - progress and priorities for future of radiation medicine and biology

After the creation of the Academy of Medical Sciences of Ukraine in 1993 the Research Center for Radiation Medicine was among the first institutions to join the Academy (fig. 1). Estab lishing the Academy was among the first steps of the independent Ukrainian government and aimed to provide a high level health care for population. It was extremely needed for the minimization of Chornobyl medical consequences. This choice was related to a growing recognition of the scientific research in fulfilling the Сenter's mission - study of the effects of low dose radiation on human body and radiation protection of the exposed population.The Center entered the Academy as a potent insti tution. Director General Dr. Anatoly Romanenko and his first deputy prof. Oles Pyatak were lucky to concentrate in three institutes of the Center a talent ed workforce including director of the Institute of Clinical Radiology prof Volodymyr Bebeshko, director of the Institute of Epidemiology and Prophylaxis of radiation Injuries prof. Volodymyr Buzunov, director of the Institute of Experimental Radiology prof. Mikhail Rudnev. Drs. T. Azaren kova, S. Galkina, V. Boer, T. Treskunova were appointed as scientific secretaries. Dosimetry divi sion was headed by brilliant prof Ilya Likhtarev and his staff Drs. I. Los, V. Korzun, V. Repin, O. Pere voznikov, O. Bondarenko, V. Chumak and others.The Center met creation of the Academy with expe rienced research and clinical staff encountering 1587 members, including 272 research staff, 28 doctors of science and 98 PhDs, modern diagnostic and labo ratory equipment, 300 beds in clinical departments and construction of hospital and out patient hospi tal in Svyatoshin. Scientific staff included experi enced prof. I. Khomaziuk, prof. B. Prevarsky, prof. V. Zamostian, prof. P. Chayalo, prof. M. Omelya nets, prof. A. Prysyazhnyuk. Dr. A. Niagu, Dr. E. Stepanova, Dr. A.Chumak, Dr. V. Klymenko, Dr. D. Komarenko, M. Pilinska, L.Ovsiannikova, O. Pi rogova. were among the first academic supervisors in studies of Chornobyl health effects and got professor certificates in this new area. First PhD theses were successfully passed by Dr. E. Gorbov, and Dr. of Sciences - by Dr. D. Bazyka. Basics of future aca demic research directions were elaborated that time by Drs. O. Kovalenko, Zh. Minchenko, V. Talko, I. Holyavka, D. Belyi, D. Yakimenko, E. Mikhai lovska, V. Malyzhev, V. Sushko, A. Cheban, K. Lo ganovsky, K. Bruslova, I. Dyagil, T. Liubarets, O. Kucher, G. Chobotko, and others. Later the major ity of these studies formed a background for Chornobyl legislation, regulatory directives, pre sented as dissertations.A quarter of century passed. The Center as a part of the National Academy of Medical Sciences resisted the challenges and moved forward, was recognized worldwide and fulfilled its main mission - providing highly qualified health care to radiation exposed. Staff numbers decreased (1,091), but work amount has increased. Since 2000, new premises were installed - a hospital with the biggest in Ukraine outpatient clin ic, new laboratory facilities, the last of which was in troduced in 2013. The Academy became a national one and since 2011 the Center was recognized as a national research institution (NRCRM), staff mem bers received 3 State Awards of Ukraine in the Field of Science and Technology, numerous personal awards.During this period, NRCRM staff conducted and published priority research data on radiation risks and molecular mechanisms of leukemia, including chronic lymphocytic, myelodysplastic syndrome, multiple myeloma, thyroid cancer, breast cancer in Chornobyl accident cleanup workers. Studies of the mechanisms of non tumor pathology - cardio vascular, cerebrovascular, cognitive disorders are in process. Of high importance are studies of possible transgenerational effects of radiation. The devel oped new technologies and protocols for the advanced care of radiation exposed were intro duced to the general health care system, the addi tional departments of oncology and chemotherapy were equipped and started activities, databases of cancer cases in exposed population and separate groups of exposed were introduced, as well as an international database of radiation injuries. The Clinical and Epidemiological registry of the NRCRM is in function and developed. An adapta tion of research directions with a respect to the pathomorphosis of radiation induced diseases in the remote period after irradiation will continue.Performed complex studies of the effects of incorporation of 131I on the fetus and the next gen eration of experimental animals became important for understanding the mechanisms of formation of radiation effects. Introduction of new foodstuffs and supplements with radiation protective proper ties was of positive effect for population protection during the first years.In the area of dosimetry a substantial progress has been achieved in reconstruction of thyroid doses in the Ukrainian population, dosimetric passportisation of settlements, radiochemistry, the creation of new methods for reconstructive dosimetry for cleanup workers - SEAD, RADRUE, and ROCKVILLE. All developments are implemented to practice, tens of thousands of doses have been restored. International recognition has received for the method of in utero doses reconstruction. As editor in chief, I regard it successful to incorporate our bilingual edition «Problems of Radiation Medicine and Radiobiology» into the NCBI MedLine, SCOPUS and other data bases, that creates an unique opportunity to widely disseminate results of the Center's research.Strategies for the future. Ukraine belongs to countries with a priority development of nuclear energy. Even with the increase in the production of clean energy, there is no other way than the further deployment of a complete nuclear fuel cycle and energy industrial complex, the expansion of the nuclear technologies to all sectors of the economy.The main potential threats to radiation safety include the aging of the material base of the NPPs with the prolongation of the working life for nuclear reactors with the expired terms of exploitation; the existence of a «nuclear legacy» sites of the former USSR in the territories of enterprises for the extrac tion and processing of uranium ores. About 5,000 institutions and enterprises use more than 25,000 sources of ionizing radiation in general. The use of radiological technologies and sources of ionizing radiation in medicine is increasing, in particular the burden on patients and staff in invasive cardiac sur gery. This will require significant efforts from the NRCRM to ensure an adequate radiation protec tion of the population, taking into account the experience collected during the mitigation of health effects of Chornobyl. Radiological threats of malev olent use of nuclear technology hasn't be forgotten.The mission of the NRCRM is to expand basic research of the health effects of ionizing radiation, elaboration and implementation of the care and radiation protection of population. Background for future is paved by a successful implementation of a special program of medical and biophysical control of personnel during transformation of the Shelter object into an environmentally safe sys tem, the State social program of increasing safty, labor hygiene and environment for 2014-2018; many years of successful cooperation with the State Nuclear Regulatory Inspectorate, the Natio nal Commission for Radiation Protection, «Ener goatom» company, the relevant departments of the Ministry of Health, international organizations such as WHO, UNSCEAR, IAEA, IARC, the US National Cancer Institute, IRSN, Nagasaki, Hiroshima, Fukushima universities and others.From the editorial board I congratulate the staff of the Center with the twenty fifth anniversary of the Academy. I would like also to wish the National Academy of Medical Sciences of Ukraine new ad vances in medical science and practice, sustainabil ity, unity, development and worldwide recognition.

Reconstructing the Linear No-Threshold Model in Japan: A Historical Perspective on the Technics of Evaluating Radiation Exposure

The 2011 nuclear power plant disaster and subsequent medical surveys of citizens in Fukushima Prefecture have helped reopen questions about competing models' effects of long-term, low-dose radiation exposure on human health. A reconstruction of how Japanese scientists studied low-dose effects of radiation in the years following the 1954 Castle Bravo detonation can deepen understandings as to why questions about the reliability of such risk analysis tools persist. Greater attention to the hopes associated with local research contributions to building international safety standards can begin to shed historical light upon how different technics of evaluating radiation effects have allowed scientists to envision either uncertain or certain futures in Japan with respect to radiation.

Contribution of Harold M. Swartz to In Vivo EPR and EPR Dosimetry

In 2015, we are celebrating half a century of research in the application of Electron Paramagnetic Resonance (EPR) as a biodosimetry tool to evaluate the dose received by irradiated people. During the EPR Biodose 2015 meeting, a special session was organized to acknowledge the pioneering contribution of Harold M. (Hal) Swartz in the field. The article summarizes his main contribution in physiology and medicine. Four emerging themes have been pursued continuously along his career since its beginning: (1) radiation biology; (2) oxygen and oxidation; (3) measuring physiology in vivo; and (4) application of these measurements in clinical medicine. The common feature among all these different subjects has been the use of magnetic resonance techniques, especially EPR. In this article, you will find an impressionist portrait of Hal Swartz with the description of the 'making of' this pioneer, a time-line perspective on his career with the creation of three National Institutes of Health-funded EPR centers, a topic-oriented perspective on his career with a description of his major contributions to Science, his role as a mentor and his influence on his academic children, his active role as founder of scientific societies and organizer of scientific meetings, and the well-deserved international recognition received so far.

A SHORT HISTORY AND CRITICAL REVIEW OF INDIVIDUAL MONITORING

Soon after the discovery of X-rays and the radioactive element radium harmful radiation effects occurred, mainly in the medical field. Consequently, the radiologists, a new profession at that time, called for a limitation of radiation exposures. First proposals were to limit the exposure rate to prevent the incidence of skin erythema. It took more than two decades and there were many victims of severe radiation effects until a sound basis for radiation protection and individual monitoring was established. For external dosimetry, the film dosemeter was invented in the 1920s. This device, often combined with an ion chamber-based pencil dosemeter, dominated the systems used in personnel dosimetry until the end of the twentieth century. For internal exposure, the concept of limiting the 'body burden' was commonly used, and only in the late 1970s, the new concept of the 'effective dose equivalent' published in ICRP publication 26 allowed for a unified interpretation and, therefore, addition of the dosimetric quantities for external and internal exposures. By the end of the last century, individual monitoring had to survive an inflation of proposals for new quantities, but fortunately, it was also the time of vast developments of new technologies, methods and procedures. Later on, much room was given to highly sophisticated regulations, requirements, metrological concepts and administrative procedures. In this complex environment, the original task of individual monitoring became more and more hidden behind secondary loads. Now, like about hundred years ago, however with different motivation, once again the ultimate goal of the professional work has to be thought about by asking: Do people always know why they do what they do? Or simply: Why individual monitoring?

Survivors and scientists: Hiroshima, Fukushima, and the Radiation Effects Research Foundation, 1975-2014

In this article, I reflect on the Radiation Effects Research Foundation and its ongoing studies of long-term radiation risk. Originally called the Atomic Bomb Casualty Commission (1947-1975), the Radiation Effects Research Foundation has carried out epidemiological research tracking the biomedical effects of radiation at Hiroshima and Nagasaki for almost 70 years. Radiation Effects Research Foundation scientists also played a key role in the assessment of populations exposed at Chernobyl and are now embarking on studies of workers at the Fukushima Daiichi Nuclear Power Plant. I examine the role of estimating dosimetry in post-disaster epidemiology, highlight how national identity and citizenship have mattered in radiation risk networks, and track how participants interpreted the relationships between nuclear weapons and nuclear energy. Industrial interests in Japan and the United States sought to draw a sharp line between the risks of nuclear war and the risks of nuclear power, but the work of the Radiation Effects Research Foundation (which became the basis of worker protection standards for the industry) and the activism of atomic bomb survivors have drawn these two nuclear domains together. This is so particularly in the wake of the Fukushima disaster, Japan's 'third atomic bombing'. The Radiation Effects Research Foundation is therefore a critical node in a complex global network of scientific institutions that adjudicate radiation risk and proclaim when it is present and when absent. Its history, I suggest, can illuminate some properties of modern disasters and the many sciences that engage with them.

Experimental microdosimetry: history, applications and recent technical advances

The invention of tissue-equivalent proportional counters simulating micrometre diameter volumes, intended to measure the linear energy transfer of a radiation field, resulted in a practical demonstration of the stochastic nature of energy deposition in small volumes. Besides contributing to a better understanding of the interactions between ionising radiation and biological systems, these detectors have had a significant impact on applied radiation dosimetry. The initial instruments were elegant but suitable only for laboratory experiments because of their sensitivity to environmental conditions and the complex support systems they required. However, their ability to separate the dose due to neutrons from that delivered by photons motivated detector design modifications that eventually resulted in robust detectors suitable for use as radiation survey instruments. Proportional counters simulating micrometre tissue volumes turned out to be the ideal detectors for monitoring the complex radiation environments, including on the space shuttle and International Space Station, and have served as the primary active dosimeters in space for nearly two decades. The need for more sophisticated measurements has led to further improvements in detector design, and the need for smaller and lighter dosimeters is motivating further developments in both detectors and data processing systems.

[V.I.Vernadskiĭ's theory of the biosphere and modern problems of radioecology]

The importance of Vernadsky's scientific heritage for the present stage of science development was substantiated. His role in the formation of radioecology as an independent scientific discipline was emphasized. The ecological consequences of an anthropogenic increase of the radiation background and the prospects of nuclear energy development were considered.

Thirty-sixth Lauriston S. Taylor Lecture on radiation protection and measurements--from the field to the laboratory and back: the what ifs, wows, and who cares of radiation biology

My scientific journey started at the University of Utah chasing fallout. It was on everything, in everything, and was distributed throughout the ecosystem. This resulted in radiation doses to humans and caused me great concern. From this concern I asked the question, "Are there health effects from these radiation doses and levels of radioactive contamination?" I have invested my scientific career trying to address this basic question. While conducting research, I got acquainted with many of the What ifs of radiation biology. The major What if in my research was, "What if we have underestimated the radiation risk for internally-deposited radioactive material?" While conducting research to address this important question, many other What ifs came up related to dose, dose rate, and dose distribution. I also encountered a large number of Wows. One of the first was when I went from conducting environmental fallout studies to research in a controlled laboratory. The activity in fallout was expressed as pCi L⁻¹, whereas it was necessary to inject laboratory animals with μCi g⁻¹ body weight to induce measurable biological changes, chromosome aberrations, and cancer. Wow! That is seven to nine orders of magnitude above the activity levels found in the environment. Other Wows have made it necessary for the field of radiation biology to make important paradigm shifts. For example, one shift involved changing from "hit theory" to total tissue responses as the result of bystander effects. Finally, Who cares? While working at U.S. Department of Energy headquarters and serving on many scientific committees, I found that science does not drive regulatory and funding decisions. Public perception and politics seem to be major driving forces. If scientific data suggested that risk had been underestimated, everyone cared. When science suggested that risk had been overestimated, no one cared. This result-dependent Who cares? was demonstrated as we tried to generate interactions by holding meetings with individuals involved in basic low-dose research, regulators, and the news media. As the scientists presented their "exciting data" that suggested that risk was overestimated, many of the regulators simply said, "We cannot use such data." The newspaper people said, "It is not possible to get such information by my editors." In spite of these difficulties, research results from basic science must be made available and considered by members of the public as well as by those that make regulatory recommendations. Public outreach of the data is critical and must continue to be a future focus to address properly the question of, "Who cares?" My journey in science, like many of yours, has been a mixture of chasing money, beatings, and the joys of unique and interesting research results. Perhaps through our experiences, we can improve research environments, funding, and use of the valuable information that is generated. Scientists that study at all levels of biological organization, from the environment to the laboratory and human epidemiology, must share expertise and data to address the What Ifs, Wows, and Who Cares of radiation biology.

Chronology of Pu isotopes and 236U in an Arctic ice core

In the present work, state of the art isotopic fingerprinting techniques are applied to an Arctic ice core in order to quantify deposition of U and Pu, and to identify possible tropospheric transport of debris from former Soviet Union test sites Semipalatinsk (Central Asia) and Novaya Zemlya (Arctic Ocean). An ice core chronology of (236)U, (239)Pu, and (240)Pu concentrations, and atom ratios, measured by accelerator mass spectrometry in a 28.6m deep ice core from the Austfonna glacier at Nordaustlandet, Svalbard is presented. The ice core chronology corresponds to the period 1949 to 1999. The main sources of Pu and (236)U contamination in the Arctic were the atmospheric nuclear detonations in the period 1945 to 1980, as global fallout, and tropospheric fallout from the former Soviet Union test sites Novaya Zemlya and Semipalatinsk. Activity concentrations of (239+240)Pu ranged from 0.008 to 0.254 mBq cm(-2) and (236)U from 0.0039 to 0.053 μBq cm(-2). Concentrations varied in concordance with (137)Cs concentrations in the same ice core. In contrast to previous published results, the concentrations of Pu and (236)U were found to be higher at depths corresponding to the pre-moratorium period (1949 to 1959) than to the post-moratorium period (1961 and 1962). The (240)Pu/(239)Pu ratio ranged from 0.15 to 0.19, and (236)U/(239)Pu ranged from 0.18 to 1.4. The Pu atom ratios ranged within the limits of global fallout in the most intensive period of nuclear atmospheric testing (1952 to 1962). To the best knowledge of the authors the present work is the first publication on biogeochemical cycles with respect to (236)U concentrations and (236)U/(239)Pu atom ratios in the Arctic and in ice cores.

An historical overview of radon and its progeny: applications and health effects

Since its discovery by Dorn in 1900, studies of radon and its progeny have contributed to such diverse scientific fields as meteorology, geophysics, mineral exploration and radiation health effects. In addition to terrestrial scientific studies of radon, NASA missions in recent decades have yielded data on the behaviour of radon and its progeny on the Moon and on Mars. Radon has been used therapeutically for ∼100 y in the form of radon seeds for the irradiation of malignant tumours. It is, however, for its negative health effects that radon is better and more justifiably known. The causal role of radon and, in particular, its progeny in the elevated incidence of lung cancer in underground uranium miners was established in the 1950s. It is of historical interest to note that the fatal lung disease of silver miners in Saxony and Bohemia in the 16th century, was undoubtedly lung cancer caused by the high levels of radon in the mines. In recent decades there has been an ever-growing interest in the public health effects of exposure to radon in homes. Extensive radon epidemiological studies both of underground miners and of the general public in recent decades have quantified the lung cancer risks from radon exposure. Radon was classified in 1988 by International Agency for Research on Cancer as a human carcinogen and in 2009 the World Health Organization identified radon as the second cause of lung cancer globally after smoking. Radon control strategies are used by many governments to control and reduce the risk to public health from radon.

Historical development and evolution of EPRI's post-closure dose assessment of potential releases to the biosphere from the proposed HLW repository at Yucca Mountain

This paper describes the development and evolution of the Electric Power Research Institute's (EPRI) post-closure dose assessment for potential releases of radionuclides from the proposed High Level Waste repository at Yucca Mountain. The starting point for this work was the 1995 publication of Technical Bases for Yucca Mountain Standards by the Commission on Geosciences, Environment and Resources of the National Research Council. This report proposed the development and application of an individual risk-based standard for releases from the repository to replace the existing one, which was based on radionuclide release limits. This in turn implied the development and application of methods to assess radiation doses to humans. Accordingly, EPRI produced a methodology for such dose assessment as part of its Total System Performance Assessment program for the proposed Yucca Mountain repository site. The methodology initially addressed releases via groundwater and then releases associated with extrusive igneous events. The methodology was updated and applied over the following years to take account of regulatory developments, changes in estimates of the source term to the biosphere, peer review through international model comparison exercises, new site generic data, and new data concerning conditions at the point of compliance in Amargosa Valley. The main outputs were Biosphere Dose Conversion Factors, which relate radionuclide levels in environmental media to the annual individual doses to a member of a hypothetical critical group and to the regulator-defined Reasonably Maximally Exposed Individual. Most recently, consideration has been given to uncertainty in the dose estimates based on a probabilistic analysis. The paper provides a perspective on the evolution of the dose assessments in response to the developments listed above.

Environmental radiation monitoring in the Chernobyl exclusion zone--history and results 25 years after

This paper describes results of the radiation environmental monitoring performed in the Chernobyl Exclusion Zone (ChEZ) during the period following the 1986 Chernobyl Nuclear Power Plant accident. This article presents a brief overview of five comprehensive reports generated under Contract No. DE-AC09-96SR18500 (Washington Savannah River Company LLC, Subcontract No. AC55559N, SOW No. ON8778) and summarizes characteristics of the ChEZ and its post-accident status. The history of development of the radiation monitoring research in the ChEZ is described also. This paper addresses the characteristics of radiation monitoring in the ChEZ, its major goals and objectives, and changes in these goals and objectives in the course of time, depending on the tasks associated with the phase of mitigation of the ChNPP accident consequences. The results of the radiation monitoring in the ChEZ during the last 25 years are also provided.

Polonium-210 and lead-210 in the terrestrial environment: a historical review

The radionuclides (210)Po and (210)Pb widely present in the terrestrial environment are the final long-lived radionuclides in the decay of (238)U in the earth's crust. Their presence in the atmosphere is due to the decay of (222)Rn diffusing from the ground. The range of activity concentrations in ground level air for (210)Po is 0.03-0.3 Bq m(-3) and for (210)Pb 0.2-1.5 Bq m(-3). In drinking water from private wells the activity concentration of (210)Po is in the order of 7-48 mBq l(-1) and for (210)Pb around 11-40 mBq l(-1). From water works, however, the activity concentration for both (210)Po and (210)Pb is only in the order of 3 mBq l(-1). Mosses, lichens and peat have a high efficiency in capturing (210)Po and (210)Pb from atmospheric fallout and exhibit an inventory of both (210)Po and (210)Pb in the order of 0.5-5 kBq m(-2) in mosses and in lichens around 0.6 kBq m(-2). The activity concentrations in lichens lies around 250 Bq kg(-1), dry mass. Reindeer and caribou graze lichen which results in an activity concentration of (210)Po and (210)Pb of about 1-15 Bq kg(-1) in meat from these animals. The food chain lichen-reindeer or caribou, and Man constitutes a unique model for studying the uptake and retention of (210)Po and (210)Pb in humans. The effective annual dose due to (210)Po and (210)Pb in people with high consumption of reindeer/caribou meat is estimated to be around 260 and 132 μSv a(-1) respectively. In soils, (210)Po is adsorbed to clay and organic colloids and the activity concentration varies with soil type and also correlates with the amount of atmospheric precipitation. The average activity concentration levels of (210)Po in various soils are in the range of 20-240 Bq kg(-1). Plants become contaminated with radioactive nuclides both by absorption from the soil (supported Po) and by deposition of radioactive fallout on the plants directly (unsupported Po). In fresh leafy plants the level of (210)Po is particularly high as the result of the direct deposition of (222)Rn daughters from atmospheric deposition. Tobacco is a terrestrial product with high activity concentrations of (210)Po and (210)Pb. The overall average activity concentration of (210)Po is 13 ± 2 Bq kg(-1). It is rather constant over time and by geographical origin. The average median daily dietary intakes of (210)Po and (210)Pb for the adult world population was estimated to 160 mBq day(-1) and 110 mBq day(-1), corresponding to annual effective doses of 70 μSv a(-1) and 28 μSv a(-1), respectively. The dietary intakes of (210)Po and (210)Pb from vegetarian food was estimated to only 70 mBq day(-1) and 40 mBq day(-1) corresponding to annual effective doses of 30.6 μSv a(-1) and 10 μSv a(-1), respectively. Since the activity concentration of (210)Po and (210)Pb in seafood is significantly higher than in vegetarian food the effective dose to populations consuming a lot of seafood might be 5-15 fold higher.

Exerpts from the history of alpha recoils

Any confined air volume holding radon ((222)Rn) gas bears a memory of past radon concentrations due to (210)Pb (T(1/2) = 22 y) and its progenies entrapped in all solid objects in the volume. The efforts of quantifying past radon exposures by means of the left-behind long-lived radon progenies started in 1987 with this author's unsuccessful trials of removing (214)Po from radon exposed glass objects. In this contribution the history and different techniques of assessing radon exposure to man in retrospect will be overviewed. The main focus will be on the implantation of alpha recoils into glass surfaces, but also potential traps in radon dwellings will be discussed. It is concluded that for a successful retrospective application, three crucial imperatives must be met, i.e. firstly, the object must persistently store a certain fraction of the created (210)Pb atoms, secondly, be resistant over decades towards disturbances from the outside and thirdly, all (210)Pb atoms analysed must originate from airborne radon only. For large-scale radon epidemiological studies, non-destructive and inexpensive measurement techniques are essential. Large-scale studies cannot be based on objects rarely found in dwellings or not available for measurements.

Fifty years of individual monitoring of ionising radiation in Switzerland: history, trends and perspectives

In the last 50 y, individual monitoring of ionising radiation in Switzerland underwent substantial development, strongly influenced by type of applications of ionising radiation, monitoring technologies, knowledge of health risks, protection philosophies and regulatory frameworks. The role of individual monitoring in the system of radiation protection moved from a passive, a posteriori control of limits towards an important and more interactive tool for optimisation. Dose trends for occupational exposures document these developments. In the future, new and emerging dose intensive applications in medicine and an increasing demand for international harmonisation, particularly in Europe, will pose new challenges in individual monitoring.

A Brazilian government external individual monitoring service: experience since 1972

Instituto de Radioproteção e Dosimetria, a Brazilian government research institute, provides individual monitoring services since 1972. Its dosemeters are: film-based thorax for whole body photons, thermoluminescence dosimetry (TLD) albedo for whole body neutrons and TLD ring for extremity photons. About 6000 radiation workers are currently being monitored with film dosemeters in 256 different facilities in Brazil, most of them working in health-related activities. Around 400 Brazilian radiation workers are monitored with TLD albedo neutron monitor and about 500 workers use TLD rings. This paper describes the monitoring systems used, presents the results obtained in internal quality programs and in intercomparison exercises and analyses the measured dose values from 1985 to 2009.

The NRPB era

Some 40 years ago, in May 1970, the Radiological Protection Bill was passed by the parliament of the United Kingdom. This legislation created the National Radiological Protection Board (NRPB). It lasted 35 years until absorbed by the Health Protection Agency in 2005. During that period, the NRPB discharged its basic duty of protecting the people from radiation hazards.

History of the measurement of radon in central Bohemia

It is a little surprising, but radon has been measured by our Institute for >50 y. In the first phase this was carried out in underground mines (up to the present day) but more and more attention has been paid to domestic dwellings and NORM workplaces. The number of the measurements (grab sampling underground, SSNTDs application) was relatively high. To the routine work of the Institute is added research and calibration for radon measuring organisations. Since the formation of the Czech Republic, our previous institution was reformed by the State Office for Nuclear Safety and is one of the two organisations whose main task is, among others, radon measurement.

Astronomical fire: Richard Carrington and the solar flare of 1859

An explosion on the Sun in 1859, serendipitously witnessed by amateur astronomer Richard Carrington, plunged telegraphic communications into chaos and bathed two thirds of the Earth's skies in aurorae. Explaining what happened to the Sun and how it could affect Earth, 93 million miles away, helped change the direction of astronomy. From being concerned principally with charting the stars to aid navigation, astronomers became increasingly concerned with what the celestial objects were, how they behaved and how they might affect life on Earth.

A review of irradiated fuel particle releases from the Windscale Piles, 1950-1957

Radiological assessments have assumed that the mass of irradiated uranium oxide particles inadvertently released to the atmosphere from the Windscale Piles, two nuclear reactors at Windscale Works, Sellafield, England, during the 1950s was 20 kg. This paper re-examines the assumptions upon which this figure was based and concludes that the value is a realistically conservative estimate of the release, consistent with current radiological protection practice. The mass estimate is derived from a reanalysis of plant data produced at the time. The environmental data on which the initial estimates were based are reconfirmed, and additional support is provided by an interpretation of modelling studies of both the total deposition and milk concentrations resulting from that deposition. Milk-monitoring data from the time are shown to be consistent with the release assumptions used in the dispersion modelling exercise. Finally, the issue of statistical undersampling is addressed using the particle numbers and size distributions produced by the modelling exercise.

History of personal dosimetry performance testing in the United States

The basis for personal dosimetry performance testing in the United States is ANSI/HPS N13.11 (2001). Now in its third edition, this standard has been in place since 1983. Testing under this standard is administered by the National Voluntary Accreditation Program (NVLAP), and accreditation of dosimetry processors under this program is required by US Nuclear Regulatory Commission (NRC) regulations. The US Department of Energy (DOE) also maintains a testing program for its laboratories and contractors, administered by the Department of Energy Laboratory Accreditation Program (DOELAP). A focus in recent years has been the modification of ANSI/HPS N13.11 to allow acceptance by both testing programs in order to bring harmonisation to US personal dosemeter processing testing. Since there is no type testing program in the US for personal dosemeters, the testing philosophy of ANSI N13.11 has always combined elements of type testing and routine performance testing. This philosophy is explored in detail in this presentation, along with trends in the development of the document to its present state. In addition, a look will be taken at what the future holds for the next revision of the document, scheduled to begin in 2005.

Environmental health physics: 50 years of progress

Environmental health physics is an interdisciplinary field, involving study of the release, transport, and fate of radioactive material in the environment. Further, it addresses the interaction of humans with radioactive materials within the ambient (outdoor) environment and with the environments associated with modern technology and lifestyles. It also involves both naturally occurring and artificially produced radionuclides with the former generally being by far the highest source of exposure. In fact, doses from naturally occurring radionuclides are increasingly being used as a benchmark for the establishment of dose rate limits for people. Because of the pioneering work of early environmental health physicists, models exist today that can be used to assess the potential impacts of new nuclear facilities prior to their operation. In fact, these people represent the branch of the health physics profession who conducted environmental monitoring programs and performed the associated research studies that led to the identification of the principal radionuclides of interest, the major pathways and mechanisms through which they expose people, and the doses that may result from radioactive materials in the natural and technologically enhanced environments. One of their most important contributions was the identification and quantification of many of the key parameters that serve as input to such models. Monitoring of nuclear weapons development facilities used during and after World War II was the initial stimulus for the establishment of environmental health physics programs. Thereafter, these programs were expanded both nationally and globally, as a result of the atmospheric weapons testing programs of nations such as France, the People's Republic of China, the former Soviet Union, the United Kingdom, and the United States. Additional stimuli were provided by the development of the commercial nuclear power industry. Current environmental programs, particularly within the U.S., focus on decontamination and decommissioning of dormant facilities from these earlier defense and commercial programs. The range of the environmental health physics aspects of these activities is the subject of this paper. Presented at the end of the paper is a summary of some of the more important lessons that have been learned. As will be noted, this is an exciting field that will present challenges to health physicists for years to come.

Linus Pauling and the scientific debate over fallout hazards

From 1954 to 1963, numerous scientists engaged in a public debate over the possible hazards from radioactive fallout from nuclear weapons testing. Nobel laureate Linus Pauling, a California Institute of Technology chemist, was one of the most prominent. His scientific papers relating to the fallout debate reveal many of the scientific, social and political issues involved in the controversy. Although the public controversy ended after the signing of the 1963 Limited Test Ban Treaty, many of the scientific questions about the possible hazards of low-level radiation remain under debate within the scientific community. Moreover, the fallout debate was a prototype of current controversies over environmental and public-health hazards.

Laboratory analyses: environmental and biological measurements

From its inception in 1951 to the present, the measurement of radioactive fallout from nuclear weapons testing and the many associated programs to establish global distribution and human health effects have contributed significantly to the understanding of worldwide dispersal of contamination. The original measurements of regional surface deposition of fallout nuclides were with duplicate gummed film collectors. Later, collectors were established in a worldwide network to measure total deposition and specific radionuclides such as 90Sr and 137Cs, which evolved into the first large-scale, global environmental monitoring network. Programs were set up to determine dietary intake and human and animal tissue distribution of 90Sr and 137Cs. Some of the first measurements of natural background dietary radium and body potassium were a response to identify analog elements. The impact of the environmental measurements made for fallout went far beyond any dosimetric consequences. For example, present day information on bone tissue turnover rates are derived mainly from radiochemical analysis of 90Sr measurements in human bone. The spin off from the enormous expenditure in effort to make these measurements and to determine the health consequences of global fallout laid a rich basic and applied scientific foundation in many disciplines, particularly in exposure pathways from ground deposition to dietary uptake and human organ biokinetics.

Historical overview of atmospheric nuclear weapons testing and estimates of fallout in the continental United States

From 1945 to 1980, over 500 weapons tests were conducted in the atmosphere at a number of locations around the world. These tests resulted in the release of substantial quantities of radioactive debris to the environment. Local, intermediate, and global fallout deposition densities downwind from test sites depended on the heights of bursts, the yields, and the half-lives and volatilities of the particular fission or activation products, as well as on the meteorological conditions. A number of national and international monitoring programs were established to trace the fallout through the atmosphere and biosphere. These programs included continuous monitoring of ground-level air, exposure rates, and deposition as well as periodic sampling of food, bone, water, soil, and stratospheric air. Although data for specific high-yield tests are still classified, the fission and fusion yields of the various tests and test series have been estimated and from this information the quantities of specific fission and activation products released into the atmosphere have been determined. The geographic and temporal variations in the fallout deposition of specific radionuclides based on both actual measurements and model calculations are discussed in this paper. A feasibility study to estimate the deposition density (deposition per unit area) of particular radionuclides from both Nevada Test Site and "global" fallout on a county-by-county scale for the continental United States is described. These deposition estimates provide a basis for reconstructing population exposure and dose. They support the feasibility of a more detailed evaluation of the population doses that resulted from fallout from atmospheric tests to document the experience fully and to report results more systematically and completely to the world community. The impact of weapons fallout will continue to be felt for years to come since a contaminant baseline has been imposed on the ambient radiation environment that will be an important factor in the assessment of past and future releases of radioactive materials into the biosphere.

The development of field-based measurement methods for radioactive fallout assessment

An overview is provided on the development of field equipment, instrument systems, and methods of analyses that were used to assess the impact of radioactive fallout from atmospheric weapons tests. Included in this review are developments in fallout collection, aerosols measurements in surface air, and high-altitude sampling with aircraft and balloons. In addition, developments in radiation measurements are covered in such areas as survey and monitoring instruments, in situ gamma-ray spectrometry, and aerial measurement systems. The history of these developments and the interplay with the general advances in the field of radiation and radioactivity metrology are highlighted. An emphasis is given as to how the modifications and improvements in the instruments and methods over time led to their adaptation to present-day applications to radiation and radioactivity measurements.

60Co contamination in recycled steel resulting in elevated civilian radiation doses: causes and challenges

Since late 1992, more than 100 building complexes containing public and private schools and nearly 1,000 apartments have been identified in Taiwan with elevated levels of gamma-radiation from construction steel contaminated with 60Co. Due to improper handling of 60Co contaminated scrap steel in late 1982 and 1983, contaminated construction materials have been widely distributed throughout the country. These contaminated construction materials have generated elevated radiation exposures to members of the public in Taiwan. As of early 1996, more than 4,000 people, including young students, have been identified as receiving more than 1 mSv y(-1) above the local background for up to 12 y. This report provides a detailed discussion of the sources of the 60Co contamination in construction steel, its discovery in the building complexes, and preliminary evaluation and remediation activities.

Radiation monitoring with reference to the medical environment

This paper discusses the general principles of monitoring with some examples taken from the medical environment. The discussion is divided into two sections. The first section deals with the principles of personnel monitoring as well as the most common types of dosimeters used. Specific techniques applicable to the various areas of radiology are delineated. The second section deals with the use of portable monitors in a medical environment. The types of instruments commonly encountered and their limitations are detailed. This section also discusses the use of portable monitors as applied to the various areas of radiology. In each section some brief historical background has been added where possible.

History of the medical uses of radiation: regulatory and voluntary standards of protection

The main focus of this paper is on the historical development of safety standards in the use of radiation or radioactive materials in medicine. However, to provide better understanding and perspective on this history, it must be interwoven with major events and advancements in the development and use of radiation, particularly in the field of medicine. Since this history, as well as that of major events that stimulated the development of radiation protection standards, is extensive, only a very brief overview can be given here. Thus, a sufficient list of references is also provided to allow further examination of detailed historical documentation, and to provide an easier entry into further research. Also, some identification of individuals who have made important contributions to the development of standards, but who are not widely identified in either the relevant standards or the historical literature, is included. This will aid the serious historian in examining files of organizations to uncover facts or rationale that could better explain historical events or developments.

Uses of therapeutic x rays in medicine

Treatment of diseases with x rays began within months of Roentgen's discovery, and within four years x rays were being used successfully for the treatment of skin cancers. Deep-seated cancers began to be treated successfully in the 1920's with the advent of "deep" x-ray units and, especially, once supervoltage therapy machines became available in the 1930's. The 1940's and 1950's saw significant growth of megavoltage therapy, initially with Van de Graaff generators and betatrons, and later with linear accelerators. Linear accelerators became popular during the 1960's and 1970's and, by the 1980's they began to replace 60Co units as the most common form of treatment machine. With high-energy linear accelerators, computerized treatment planning, and ingenious fractionation schemes, modern radiotherapy has become a vital component of cancer treatment.

A history of medical internal dosimetry

This paper presents a short history of the development of medical internal dosimetry. It reviews the evolution of the equations and discusses the development of various mathematical models used to improve radiation absorbed dose estimates. The contributions of Leonidas Marinelli, Edith Quimby, William Mayneord, Robert Loevinger, Walter Snyder, and others are emphasized.