WorldWideScience

Sample records for acute radiation risk

  1. Evidence Report: Risk of Acute and Late Central Nervous System Effects from Radiation Exposure

    Nelson, Gregory A.; Simonsen, Lisa; Huff, Janice L.

    2016-01-01

    Possible acute and late risks to the central nervous system (CNS) from galactic cosmic rays (GCR) and solar particle events (SPE) are concerns for human exploration of space. Acute CNS risks may include: altered cognitive function, reduced motor function, and behavioral changes, all of which may affect performance and human health. Late CNS risks may include neurological disorders such as Alzheimer's disease (AD), dementia and premature aging. Although detrimental CNS changes are observed in humans treated with high-dose radiation (e.g., gamma rays and 9 protons) for cancer and are supported by experimental evidence showing neurocognitive and behavioral effects in animal models, the significance of these results on the morbidity to astronauts has not been elucidated. There is a lack of human epidemiology data on which to base CNS risk estimates; therefore, risk projection based on scaling to human data, as done for cancer risk, is not possible for CNS risks. Research specific to the spaceflight environment using animal and cell models must be compiled to quantify the magnitude of CNS changes in order to estimate this risk and to establish validity of the current permissible exposure limits (PELs). In addition, the impact of radiation exposure in combination with individual sensitivity or other space flight factors, as well as assessment of the need for biological/pharmaceutical countermeasures, will be considered after further definition of CNS risk occurs.

  2. Evidence Report: Risk of Acute Radiation Syndromes Due to Solar Particle Events

    Carnell, Lisa; Blattnig, Steve; Hu, Shaowen; Huff, Janice; Kim, Myung-Hee; Norman, Ryan; Patel, Zarana; Simonsen, Lisa; Wu, Honglu

    2016-01-01

    Crew health and performance may be impacted by a major solar particle event (SPE), multiple SPEs, or the cumulative effect of galactic cosmic rays (GCR) and SPEs. Beyond low-Earth orbit, the protection of the Earth's magnetosphere is no longer available, such that increased shielding and protective mechanisms are necessary in order to prevent acute radiation sickness and impacts to mission success or crew survival. While operational monitoring and shielding are expected to minimize radiation exposures, there are EVA scenarios outside of low-Earth orbit where the risk of prodromal effects, including nausea, vomiting, anorexia, and fatigue, as well as skin injury and depletion of the blood-forming organs (BFO), may occur. There is a reasonable concern that a compromised immune system due to high skin doses from a SPE or due to synergistic space flight factors (e.g., microgravity) may lead to increased risk to the BFO. The primary data available at present are derived from analyses of medical patients and persons accidentally exposed to acute, high doses of low-linear energy transfer (LET) (or terrestrial) radiation. Data more specific to the space flight environment must be compiled to quantify the magnitude of increase of this risk and to develop appropriate protection strategies. In particular, information addressing the distinct differences between solar proton exposures and terrestrial exposure scenarios, including radiation quality, dose-rate effects, and non-uniform dose distributions, is required for accurate risk estimation.

  3. 2013 Space Radiation Standing Review Panel Status Review for: The Risk of Acute and Late Central Nervous System Effects from Radiation Exposure, The Risk of Acute Radiation Syndromes Due to Solar Particle Events (SPEs), The Risk Of Degenerative Tissue Or Other Health Effects From Radiation Exposure, and The Risk of Radiation Carcinogenesis

    2014-01-01

    The Space Radiation Standing Review Panel (from here on referred to as the SRP) was impressed with the strong research program presented by the scientists and staff associated with NASA's Space Radiation Program Element and National Space Biomedical Research Institute (NSBRI). The presentations given on-site and the reports of ongoing research that were provided in advance indicated the potential Risk of Acute and Late Central Nervous System Effects from Radiation Exposure (CNS) and were extensively discussed by the SRP. This new data leads the SRP to recommend that a higher priority should be placed on research designed to identify and understand these risks at the mechanistic level. To support this effort the SRP feels that a shift of emphasis from Acute Radiation Syndromes (ARS) and carcinogenesis to CNS-related endpoints is justified at this point. However, these research efforts need to focus on mechanisms, should follow pace with advances in the field of CNS in general and should consider the specific comments and suggestions made by the SRP as outlined below. The SRP further recommends that the Space Radiation Program Element continue with its efforts to fill the vacant positions (Element Scientist, CNS Risk Discipline Lead) as soon as possible. The SRP also strongly recommends that NASA should continue the NASA Space Radiation Summer School. In addition to these broad recommendations, there are specific comments/recommendations noted for each risk, described in detail below.

  4. Radiation risks

    This report contains an evaluation of data available about the deleterious effects of exposure of people to ionising radiation, assuming that the total exposure is low (low dose) or that exposure to dose takes place gradually (low dose rate). It is a revision of the 1985 Health Council report on 'The scientific foundations for radiation protection policy based on the UNSCEAR-77, -82, and BEIR reports'. The report is also meant to be a reply to a request for advice made by the Minister of Welfare, Public Health and Culture in 1989. Scientific opinion on induction of cancer by radiation has clearly changed since 1988. This is a consequence of new publications of epidemiological studies among survivors of the atomic explosions of Hiroshima and Nagasaki. The Committee that has produced the present report has paid much attention to this development. Besides, in the request for advice just mentioned it is asked whether the margins of uncertainty which complicated the quantitative assessment of the radiation risk can be reduced. Consequently the Committee has dealt extensively with the potential errors and uncertainties in available data. Especially these 2 elements - a careful consideration of a recent shift in scientific opinion and a constant attention for the magnitude of potential uncertainties - have had a predominant influence on the content and design of this report. The Committee has tried to answer as fully as possible the complex question how to transform results of scientific research into a well-organised data set on which the government can base its radiation protection policy. The Committee had also compared its evaluation to the recent recommendations of the International Commission on Radiological Protection (ICRP) and the points of view of the Dutch policy directive 'Dealing with radiation risks'. (author). 111 refs.; 12 tabs

  5. Acute radiation disease

    Features of clinical trends in acute period of radiation disease at personnel who suffered from Chernobyl accident are considered. The main attention is paid to the results of 10 year observation of organs, systems and metabolic processes in patients. Used therapeutic, rehabilitation and preventive actions in stationary, ambulatory and sanatorium - health resort stages are described

  6. The implications of re-analysing radiation-induced leukaemia in atomic bomb survivors: risks for acute and chronic exposures are different

    Implications of risk estimates, as required for practical radiation protection purposes, were explored through a preliminary re-analysis of leukaemia in the Japanese atomic bomb survivors using a biologically based cancer model. The calculations for the risks posed for contracting leukaemia pointed to important differences between low-dose-rate ('chronic') and high-dose-rate ('acute') exposures. For example, the risks caused by long-term ('chronic') exposures are calculated to be substantially lower than those for 'acute' exposures. In view of these model predictions the results of epidemiological studies are discussed. (author)

  7. Statistical Prediction of Solar Particle Event Frequency Based on the Measurements of Recent Solar Cycles for Acute Radiation Risk Analysis

    Myung-Hee, Y. Kim; Shaowen, Hu; Cucinotta, Francis A.

    2009-01-01

    Large solar particle events (SPEs) present significant acute radiation risks to the crew members during extra-vehicular activities (EVAs) or in lightly shielded space vehicles for space missions beyond the protection of the Earth's magnetic field. Acute radiation sickness (ARS) can impair performance and result in failure of the mission. Improved forecasting capability and/or early-warning systems and proper shielding solutions are required to stay within NASA's short-term dose limits. Exactly how to make use of observations of SPEs for predicting occurrence and size is a great challenge, because SPE occurrences themselves are random in nature even though the expected frequency of SPEs is strongly influenced by the time position within the solar activity cycle. Therefore, we developed a probabilistic model approach, where a cumulative expected occurrence curve of SPEs for a typical solar cycle was formed from a non-homogeneous Poisson process model fitted to a database of proton fluence measurements of SPEs that occurred during the past 5 solar cycles (19 - 23) and those of large SPEs identified from impulsive nitrate enhancements in polar ice. From the fitted model, the expected frequency of SPEs was estimated at any given proton fluence threshold (Phi(sub E)) with energy (E) >30 MeV during a defined space mission period. Corresponding Phi(sub E) (E=30, 60, and 100 MeV) fluence distributions were simulated with a random draw from a gamma distribution, and applied for SPE ARS risk analysis for a specific mission period. It has been found that the accurate prediction of deep-seated organ doses was more precisely predicted at high energies, Phi(sub 100), than at lower energies such as Phi(sub 30) or Phi(sub 60), because of the high penetration depth of high energy protons. Estimates of ARS are then described for 90th and 95th percentile events for several mission lengths and for several likely organ dose-rates. The ability to accurately measure high energy protons

  8. Risk factors of radiation-induced acute esophagitis in non-small cell lung cancer patients treated with concomitant chemoradiotherapy

    To analyze the clinical and dosimetric risk factors of acute esophagitis (AE) in non-small-cell lung cancer (NSCLC) patients treated with concomitant chemoradiotherapy. Seventy-six NSCLC patients treated with concomitant chemoradiotherapy were retrospectively analyzed. Forty-one patients received concomitant chemoradiotherapy with vinorelbine/cisplatin (VC), 35 with docetaxel/cisplatin (DC). AE was graded according to criteria of the Radiation Therapy Oncology Group (RTOG). The following clinical and dosimetric parameters were analyzed: gender, age, clinical stage, Karnofsky performance status (KPS), pretreatment weight loss, concomitant chemotherapy agents (CCA) (VC vs. DC), percentage of esophagus volume treated to ≥20 (V20), ≥30 (V30), ≥40 (V40), ≥50 (V50) and ≥60 Gy (V60), and the maximum (Dmax) and mean doses (Dmean) delivered to esophagus. Univariate and multivariate logistic regression analysis were used to test the association between the different factors and AE. Seventy patients developed AE (Grade 1, 19 patients; Grade 2, 36 patients; and Grade 3, 15 patients). By multivariate logistic regression analysis, V40 was the only statistically significant factor associated with Grade ≥2 AE (p<0.001, OR = 1.159). A V40 of <23% had a 33.3% (10/30) risk of Grade ≥2 AE, which increased to 89.1% (41/46) with a V40 of ≥23% (p<0.001). CCA (p =0.01; OR = 9.686) and V50 (p<0.001; OR = 1.122) were most significantly correlated with grade 3 AE. A V50 of <26.5% had a 6.7% (3/45) risk of Grade 3 AE, which increased to 38.7% (12/31) with a V50 of ≥26.5% (p = 0.001). On the linear regression analysis, V50 and CCA were significant independent factors affecting AE duration. Patients who received concomitant chemotherapy with VC had a decreased risk of grade 3 AE and shorter duration compared with DC. Concomitant chemotherapy agents have potential influence on AE. Concomitant chemotherapy with VC led to lower risk of AE compared with that using DC. V40 and V50

  9. Sarcoma risk after radiation exposure

    Berrington de Gonzalez Amy

    2012-10-01

    Full Text Available Abstract Sarcomas were one of the first solid cancers to be linked to ionizing radiation exposure. We reviewed the current evidence on this relationship, focusing particularly on the studies that had individual estimates of radiation doses. There is clear evidence of an increased risk of both bone and soft tissue sarcomas after high-dose fractionated radiation exposure (10 + Gy in childhood, and the risk increases approximately linearly in dose, at least up to 40 Gy. There are few studies available of sarcoma after radiotherapy in adulthood for cancer, but data from cancer registries and studies of treatment for benign conditions confirm that the risk of sarcoma is also increased in this age-group after fractionated high-dose exposure. New findings from the long-term follow-up of the Japanese atomic bomb survivors suggest, for the first time, that sarcomas can be induced by acute lower-doses of radiation (

  10. Comprehending radiation risks

    This paper introduces the problem area covered by nine papers submitted through Riskkollegiet (a Swedish academy on risk) to the IAEA at their request. It introduces the basic concepts of radioactivity, radioactive substances, ionizing radiation and radiation dose, as well as the general concept of risk. The concept ''risk'' has no universally accepted definition and the word ''risk'' is used with several different meanings. The authors discuss attributes usually employed in quantitative presentations of risk: probability of harmful events, and the consequences, should such events occur, but also non-quantitative aspects involved in risk perception, risk comparisons and risk communication. (author)

  11. The acute radiation syndrome

    Symptoms and signs from medical aspects resulting from whole body exposure, or in the main part, to ionizing radiation are described. The dose-response relationship is studied and the exposure is divided in three parts: central nervous system syndrome, gastrointestinal syndrome and hematopoietic syndrome. Brief comments about the treatment are reported. (M.A.C.)

  12. Radiation risk estimation models.

    Hoel, D. G.

    1987-01-01

    Cancer risk models and their relationship to ionizing radiation are discussed. There are many model assumptions and risk factors that have a large quantitative impact on the cancer risk estimates. Other health end points such as mental retardation may be an even more serious risk than cancer for those with in utero exposures.

  13. The risks of radiation

    Miettenen, Jorma K.

    1988-01-01

    The risks of radioactivity are a really complicated matter, yet they are much better known than are the risks relating to thousands of chemical poisons that occur in our environment. The greatest mistakes are probably made in the definition of safety margins. Except for the bombs dropped in Japan and one other case in the Marshall Islands, there has always—luckily—been a wide safety margin between fallout radiation and doses dangerous to health; the margin has actually been about 1000-fold. The Chernobyl dose of 0.5 mGy/year that we received is only 1/1000 of the acute dose of 0.5 Gy which would cause a slight and nonpermanent change in the blood picture. There is no such safety margin with respect to many air pollutants. The safety standards for sulfuric or nitric oxides, ozone and so on, have been set only just below the level that already causes a health hazard, and these standards are exceeded once in a while. Otherwise, traffic would have to be forbidden and many industrial plants, especially power stations using coal, would have to stop working whenever a low-temperature inversion occurred. Environmental radioactivity does not represent a likely health risk in Finland unless a nuclear war breaks out. Air pollutants, on the contrary, are a real and almost daily health risk that should be carefully considered when decisions about our energy production are being made. In spite of what happened at Chernobyl, global consumption of nuclear power will double by the year 2000, since there are about 140 nuclear power plants presently under construction. It is not likely that another catastrophe like Chernobyl will happen, yet nuclear plant accidents are of course possible, even if their likelihood is diminished by improving reactor safety and even if any eventual damage could be expected to be smaller. If a reactor is hooded by a containment structure, no significant release of radioactive materials should be possible even in case of an accident. However, we must

  14. Mammography and radiation risk

    Breast cancer is the most frequent malignant neoplasia among women in Germany. The use of mammography as the most relevant diagnostic procedure has increased rapidly over the last decade. Radiation risks associated with mammography may be estimated from the results of numerous epidemiological studies providing risk coefficients for breast cancer in relation to age at exposure. Various calculations can be performed using the risk coefficients. For instance, a single mammography examination (bilateral, two views of each breast) of a women aged 45 may enhance the risk of developing breast cancer during her lifetime numerically from about 12% of 12.0036%. This increase in risk is lower by a factor of 3,300 as compared to the risk of developing breast cancer in the absence of radiation exposure. At the age of 40 or more, the benefit of mammography exceeds the radiation risk by a factor of about 100. At higher ages this factor increases further. Finally, the dualism of individual risk and collective risk is considered. It is shown that the individual risk of a patient, even after multiple mammography examinations, is vanishingly small. Nevertheless, the basic principle of minimising radiation exposure must be followed to keep the collective risk in the total population as low as reasonably achievable. (orig.)

  15. Perception of radiation risks

    Perception of risks by people depends on many factors, either characterizing the individuals, or specific to the risk sources. The risk concept, which confuses the issue, is precised first. Second, the perception phenomenon is presented as an interactive process involving the individual, the hazard, and the social context. Third, dimensions of perception are listed and used to describe the perception of radiation risks. Finally, the relation between perception and attitude is clarified. (author) 50 refs

  16. Risk Preferences under Acute Stress

    Cingl, Lubomír; Cahlíková, Jana

    2013-01-01

    Many important decisions are made under stress and they often involve risky alternatives. There has been ample evidence that stress influences decision making in cognitive as well as in affective domains, but still very little is known about whether individual attitudes to risk change with exposure to acute stress. To directly evaluate the causal effect of stress on risk attitudes, we adopt an experimental approach in which we randomly expose participants to a psychosocial stressor in the for...

  17. Modeling the Risk of Radiation-Induced Acute Esophagitis for Combined Washington University and RTOG Trial 93-11 Lung Cancer Patients

    Purpose: To construct a maximally predictive model of the risk of severe acute esophagitis (AE) for patients who receive definitive radiation therapy (RT) for non–small-cell lung cancer. Methods and Materials: The dataset includes Washington University and RTOG 93-11 clinical trial data (events/patients: 120/374, WUSTL = 101/237, RTOG9311 = 19/137). Statistical model building was performed based on dosimetric and clinical parameters (patient age, sex, weight loss, pretreatment chemotherapy, concurrent chemotherapy, fraction size). A wide range of dose–volume parameters were extracted from dearchived treatment plans, including Dx, Vx, MOHx (mean of hottest x% volume), MOCx (mean of coldest x% volume), and gEUD (generalized equivalent uniform dose) values. Results: The most significant single parameters for predicting acute esophagitis (RTOG Grade 2 or greater) were MOH85, mean esophagus dose (MED), and V30. A superior–inferior weighted dose-center position was derived but not found to be significant. Fraction size was found to be significant on univariate logistic analysis (Spearman R = 0.421, p < 0.00001) but not multivariate logistic modeling. Cross-validation model building was used to determine that an optimal model size needed only two parameters (MOH85 and concurrent chemotherapy, robustly selected on bootstrap model-rebuilding). Mean esophagus dose (MED) is preferred instead of MOH85, as it gives nearly the same statistical performance and is easier to compute. AE risk is given as a logistic function of (0.0688 ∗ MED+1.50 ∗ ConChemo-3.13), where MED is in Gy and ConChemo is either 1 (yes) if concurrent chemotherapy was given, or 0 (no). This model correlates to the observed risk of AE with a Spearman coefficient of 0.629 (p < 0.000001). Conclusions: Multivariate statistical model building with cross-validation suggests that a two-variable logistic model based on mean dose and the use of concurrent chemotherapy robustly predicts acute esophagitis

  18. Health Impacts from Acute Radiation Exposure

    Strom, Daniel J.

    2003-09-30

    Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

  19. Acute radiation syndrome in human

    The combination of the different types of irradiation dramatically changes the clinical course of acute radiation syndrome (ARS) in the case of short term exposure. The recent experience has been compared mostly with the data on the atomic bomb victims in Hiroshima and Nagasaki. The comparison of the injuries from different radiation exposures resulted in the possibility to receive summarized data and the actual basis of the observed difference. The situation with total relatively uniform irradiation is observed when human position is at long distance from powerful radiation sources or when he changes his position, as seen in atomic bomb survivors, the results of nuclear weapon tests and the patients in the Chernobyl accident. This is connected with the ARS of bone, marrow and intestine. The situation characterized by the clinical signs of the large area of skin and mucosa injuries was observed in nuclear weapon tests and the Chernobyl accident. In the case of the more localized and less severe beta injuries of skin and mucosa, the long term effects may be important. The majority of accidents in peaceful period are related to the uneven exposure from near sources, and the situation of the combination of external and internal irradiation is related to uneven irradiation and the predominance of internal exposure. (K.I.)

  20. Clinical and dosimetric risk factors of acute radiation esophagitis in non-small cell lung cancer patients treated with three-dimensional conformal radiotherapy

    Objective: To analyze the clinical and dosimetric risk factors for acute radiation esophagitis (ARE) in non-small cell lung cancer (NSCLC) patients treated with three-dimensional conformal radiotherapy (3D-CRT), and to find significant risk factors for clinical therapy. Methods: A total of 102 NSCLC patients treated with 3D-CRT were retrospectively analyzed.ARE was scored according to the Radiation Therapy Oncology Group (RTOG) criteria with grade 2 or worse. Patients were divided into non-concurrent chemoradiotherapy group and concurrent chemoradiotherapy group. The clinical and dosimetric factors associated with grade 2 or worse ARE were analyzed using univariate logistic regression, multivariate logistic analysis and receiver operating characteristic (ROC) curve. Results: There were no grade 4 or 5 ARE observed in the 102 patients. Nineteen developed grade 2, 15 developed grade 3. In non-concurrent chemoradiotherapy group,multivariate analysis showed that V55 was the only risk factor of grade 2/3 ARE. For ROC curve analysis, the cut-off point of V55 was 16.0 while the area under ROC curve was 0.870 (95% CI: 0.782-0.957, P<0.05). In concurrent chemoradiotherapy group, multivariate analysis showed that V35 and chemotherapy regimens during radiotherapy were risk factors of grade 2/3 ARE. The cut-off point of V35 was 23.75 while the area under ROC curve was 0.782 (95% CI: 0.636-0.927, P<0.05). Vinorelbine and cisplatin regimen showed low incidence of ARE contrast with gemcitabine/docetaxel and cisplatin regimens (33.3% and 66.7%). Conclusions: V55 is the only statistically significant risk factor associated with grade 2 or worse ARE for patients who don't accepted concurrent chemotherapy. V35 and chemotherapy regimens during radiotherapy are statistically significant risk factors associated with grade 2 or worse ARE for patients who accept concurrent chemotherapy. Vinorelbine and cisplatin regimen during radiotherapy shows low incidence of ARE. (authors)

  1. Radiation risk estimation

    This report outlines the major publications between 1976 and 1981 that have contributed to the evolution of the way in which radiation risks (cancer and hereditary birth defects) are assessed. The publications include the latest findings of the UNSCEAR, BEIR and ICRP committees, epidemiological studies at low doses and new assessments of the doses received by the Japanese A-bomb survivors. This report is not a detailed critique of those publications, but it highlights the impact of their findings on risk assessment

  2. Estimating risk from acute exposures- new concepts

    Risk from acute exposures at different ages is calculated by the ICRP-60 methodology using Indian and Swedish-ICRP baseline data. The results demonstrate a considerably lower significance for exposures at higher ages. For acute exposures in the age range 0-45 years, more than half the fatality probability and more than one fourth the person-years of life lost are expressed above age 65 years. The Indian values of these parameters are a factor of 2 to 3 lower than those for the Swedish-ICRP values. The results are compared with those obtained by the Biological Effects of Ionizing Radiation (BEIR V) method. (author). 4 refs., 1 tab., 1 fig

  3. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Dörr Harald; Meineke Viktor

    2011-01-01

    Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the ab...

  4. Radiation effects and radiation risks

    The book presents the facts and the principles of assessment and evaluation of biological radiation effects in general and also with particular reference to the reactor accident of Chernobyl, reviewing the consequences and the environmental situation on the basis of current national and international literature, including research work by the authors. The material compiled in this book is intended especially for physicians, but will also prove useful for persons working in the public health services, in administration, or other services taking care of people. The authors tried to find an easily comprehensible way of presenting and explaining the very complex processes and mechanisms of biological radiation effects and carcinogenesis, displaying the physical primary processes and the mechanisms of the molecular radiation effects up to the effects of low-level radiation, and present results of comparative epidemiologic studies. This section has been given considerable space, in proportion to its significance. It also contains literature references for further reading, offering more insight and knowledge of aspects of special subject fields. The authors also present less known results and data and discuss them against the background of well-known research results and approaches. Apart from the purpose of presenting comprehensive information, the authors intend to give an impact for further thinking about the problems, and helpful tools for independent decisions and action on the basis of improved insight and assessment, and in this context particularly point to the problems induced by the Chernobyl reactor accident. (orig./MG) With 8 maps in appendix

  5. Radiobiology of the acute radiation syndrome

    Acute radiation syndrome or acute radiation sickness is classically subdivided into three sub syndromes: the hematopoietic, gastrointestinal and neurovascular syndrome but many other tissues can be damaged. The time course and severity of clinical signs and symptoms are a function of the overall body volume irradiated, the inhomogeneity of dose exposure, the particle type, the absorbed dose and the dose rate. Classical pathophysiology explain the failure of each of these organs and the timing of appearance of their signs and symptoms due to radiation-induced cytocidal effects of a great number of parenchymal cells of hierarchically organized tissues. Contemporaneously, many other radiation-induced effects has been described and all of them may lead to tissue injury with their corresponding signs and symptoms that can be expressed after short or long period of time. Radiation-induced multi-organ involvement is thought to be due to radiation-induced systemic inflammatory response mediated by released pro-inflammatory cytokines. (authors)

  6. Risk Factors: Radiation

    Radiation of certain wavelengths, called ionizing radiation, has enough energy to damage DNA and cause cancer. Ionizing radiation includes radon, x-rays, gamma rays, and other forms of high-energy radiation.

  7. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Dörr Harald

    2011-11-01

    Full Text Available Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

  8. Diet and risk of acute pancreatitis

    Oskarsson, Viktor

    2016-01-01

    Acute pancreatitis is a sudden inflammation of the pancreas. It has a broad spectrum of clinical outcomes, ranging from mild and self-limiting to severe and potentially fatal, and is often followed by recurrent attacks and/or progression to a chronic disease state (so-called chronic pancreatitis); especially if it is classified as non-gallstone-related acute pancreatitis. Alcohol abuse is considered to be the most important risk factor for non-gallstone-related acute pancreatitis. Even though...

  9. Radiation exposures: risks and realities

    Discovery of radioactivity in 1869 by Henry Becquerel and artificial radioactivity by Irene Curie in 1934 led to the development of nuclear field and nuclear materials in 20th century. They are widely used for man-kind across the globe in electricity production, carbon dating, treatment and diagnosis of diseases etc. While deriving benefits and utilizing nuclear resources for the benefit of man-kind, it is inevitable that exposure to radiation can not be avoided. Radiation exists all around us either natural or man-made which can not be totally eliminated or avoided. Radiation exposures from natural background contribute 2.4 to 3.6 mSv in a year. Radiation exposures incurred by a member of public due to nuclear industries constitute less than one hundredth of annual dose due to natural background. Hence it is important to understand the risk posed by radiation and comparison of radiation risk with various risks arising due to other sources. Studies have indicated that risks due to environmental pollution, cigarette smoking, alcohol consumption, heart diseases are far higher in magnitude compared to radiation risks from man made sources. This paper brings about the details and awareness regarding radiation exposures, radiation risk, various risks associated with other industries and benefits of radiation exposures. (author)

  10. Does radiation risk exist?

    Risk assessment and risk management are parts of a dynamic process with the objective to decide on the tolerability of risk and on measures to keep risk within accepted limits. It enables all relevant parties to express their concerns and preferences regarding the different options for the human action involved and regarding the relative importance of criteria to decide on the tolerability of risk. Risk assessment has three phases; problem definition, risk analysis and risk characterization. Risk analysis is primarily a technical and scientific endeavour. With regard to problem definition and ride characterization consultation between risk assessors and risk managers (and other parties concerned) is a must. (author)

  11. Risk assessment after acute upper gastrointestinal haemorrhage.

    Rockall, T A; Logan, R F; Devlin, H. B.; Northfield, T. C.

    1996-01-01

    The aim of this study was to establish the relative importance of risk factors for mortality after acute upper gastrointestinal haemorrhage, and to formulate a simple numerical scoring system that categorizes patients by risk. A prospective, unselected, multicentre, population based study was undertaken using standardised questionnaires in two phases one year apart. A total of 4185 cases of acute upper gastrointestinal haemorrhage over the age of 16 identified over a four month period in 1993...

  12. Radiation risk and radiation protection concepts

    The revised dosimetry for the survivors of Hiroshima and Nagasaki implies an increased risk from low LET radiation compared with that currently used. During its meeting in 1987 the ICRP stated that the new data at present do not require any change in the dose limits. However, two other factors can cause larger changes in the present risk estimates. Firstly, for some types of cancer the relative risk model seems to describe the observed data better than the absolute risk model currently used by the ICRP. Secondly, the shape of the dose-response relationship considerably influences the derived risks. In the present paper the factor causing a substantial increase in radiation risk are analyzed. Conclusions are drawn in how far a change in the currently recommended dose limits seems to be necessary. (author)

  13. Radiation therapy in prostate cancer: evaluation of acute toxicity

    Goals: The present work documents the increasing demand of curative intent radiation therapy (CIRT) for localized prostate cancer and assesses acute reactions caused by ionizing radiation to intrapelvic organs. Patients and methods: From January 1995 to December 2001, 166 patients with prostatic cancer received radiation therapy, 70% of them (n=116) with curative intent. Treatment was completed as planned in 108 patients: 55 with pelvic irradiation and prostatic boost (PRT), 42 with three-dimensional conformal radiotherapy (3DCRT), 10 with a permanent 125 I implant (IPI) and 1 with combined radiotherapy. Patients were classified as at high- or low-risk according to tumor volume, Gleason score, regional lymph node status and pretreatment specific prostatic antigen level. High-risk patients were assigned to PRT and low-risk patients to local treatment only (either 3DCRT or IPI). Mean doses were 46 Gy for pelvis and 73 Gy for prostate with PRT; 75 Gy with 3DCRT and 127 Gy with IPI and combined radiation therapy. Acute rectal toxicity (ART) and acute urinary toxicity (AUT) were assessed according to the RTOG scale. Statistical analysis was performed with Fischer's exact test. Results: The proportion of patients receiving CIRT increased from 46% (n=28) in 1995-1998 to 84% (n=88) in 1999-2001; p < 0.0001. No patient developed ART or AUT beyond degree 2. ART was lower with 3DCRT (71% degree 0 or 1) than with PRT (45% degree 0 or 1); p= 0.0134. No significant difference was found in AUT. Conclusions: In recent years the demand for CIRT has almost doubled, with a concomitant decrease in palliative radiotherapy. In high-risk patients, pelvic irradiation increased mild and moderate ART, without compromising their life quality. None of the techniques employed was associated with severe acute toxicity. (author)

  14. Ionizing radiation and occupational risks

    This brochure gives information about the risks of working with ionizing radiation. It tries to give answers to frequently posed questions, like; what is ionizing radiation; what are the biological consequences; which are the juridicial rules for inspection and control in the Netherlands. The auditory of the publication is thought to be: radiological workers, or employees working in the neighbourhood of ionizing radiation sources, radiation experts, safety experts and medical officers. (Auth.)

  15. Carcinogenic risks of radiations

    Ionising radiations are known since the end of the 19th century. Early, after being discovered, they were applied in Medicine and the association with an increased number of different malignant tumors was proved. This paper presents a literature review concerning epidemiological proof of radiation induced cancer, molecular mechanisms and factors that increase or decrease the carcinogenic action of ionizing radiations

  16. Evaluation and management of acute radiation dermatitis

    Acute radiation dermatitis remains one of the most commonly observed side effect during radiation therapy leading to complication such as superinfection or treatment disruption. Its management is characterized by a great heterogeneity. Few strategies have demonstrated a benefit in preventing radiation dermatitis, which relies mostly on decreasing dose delivered to the skin and skin care practices. Simple emollients and use of topical steroids can be useful in early stages. The singularity of the skin toxicity seen with cetuximab and radiotherapy warrants a specific grading system and distinctive clinical treatment with use of antibiotics. (authors)

  17. Ionizing radiation: benefits vs. risks

    No one has been identifiably injured by radiation within the levels set by the NCRP and ICRP in 1934. This fact and the level of natural radiation (average dose 102 millirems/year) help provide standards against which the authors can view the relative increases in exposure from manmade sources of radiation. Because one person in five in the US will die of cancer from all causes, it is impossible to detect small increases in some types of cancer from radiation. A valid assumption is that any exposure to radiation carries some possibility of harm and should be kept below the level of the expected benefits. More is known about radiation toxicity than about any other potentially toxic substances. An obstacle to progress in the use of radioactive materials in biology and medicine is an exaggerated impression by the public of the risk of radiation. Several studies indicate that the public perceives the risk of radiation to be the greatest of all societal risks and at times does not distinguish peaceful from military uses of radiation. It behooves scientists and physicians to inform the public about the benefits as well as the risks of procedures involving radiation

  18. Radiation Protection for Manned Interplanetary Missions - Radiation Sources, Risks, Remedies

    Facius, R.; Reitz, G.

    Health risks in interplanetary explorative missions differ in two major features significantly from those during the manned missions experienced so far. For one, presently available technologies lead to durations of such missions significantly longer than so far encountered - with the added complication that emergency returns are ruled out. Thus radiation exposures and hence risks for late radiation sequelae like cancer increase proportional to mission duration - similar like most other health and many technical risks too. Secondly, loss of the geomagnetic shielding available in low earth orbits (LEO) does increase the radiation dose rates from galactic cosmic rays (GCR) since significant fractions of the GCR flux below about 10 GeV/n now can reach the space vehicle. In addition, radiation from solar particle events (SPE) which at most in polar orbit segments can contribute to the radiation exposure during LEO missions now can reach the spaceship unattenuated. Radiation doses from extreme SPEs can reach levels where even early acute radiation sickness might ensue - with the added risks from potentially associated crew performance decrements. In contrast to the by and large predictable GCR contribution, the doses and hence risks from large SPEs can only stochastically be assessed. Mission designers face the task to contain the overall health risk within acceptable limits. Towards this end they have to transport the particle fluxes of the radiation fields in free space through the walls of the spaceship and through the tissue of the astronaut to the radiation sensitive organs. To obtain a quantity which is useful for risk assessment, the radiobiological effectiveness as well as the specific sensitivity of a given organ has to be accounted for in such transport calculations which of course require a detailed knowledge of the spatial distribution and the atomic composition of the surrounding shielding material. In doing so the mission designer encounters two major

  19. Competing risk theory and radiation risk assessment

    New statistical procedures are applied to estimate cumulative distribution functions (c.d.f.), force of mortality, and latent period for radiation-induced malignancies. It is demonstrated that correction for competing risks influences the shape of dose response curves, estimates of the latent period, and of the risk from ionizing radiations. The equivalence of the following concepts is demonstrated: force of mortality, hazard rate, and age or time specific incidence. This equivalence makes it possible to use procedures from reliability analysis and demography for radiation risk assessment. Two methods used by reliability analysts - hazard plotting and total time on test plots - are discussed in some detail and applied to characterize the hazard rate in radiation carcinogenesis. C.d.f.'s with increasing, decreasing, or constant hazard rate have different shapes and are shown to yield different dose-response curves for continuous irradiation. Absolute risk is shown to be a sound estimator only if the force of mortality is constant for the exposed and the control group. Dose-response relationships that use the absolute risk as a measure for the effect turn out to be special cases of dose-response relationships that measure the effect with cumulative incidence. (H.K.)

  20. Perception of radiation risk

    The perception of risk depends on the context of a hazard, on the type of hazard, and on the type of persons who make the judgements. In addition, investigations of perceived risk are sensitive to the choice of methodology and study design. Perceptions of hazards, and risk ratings, must therefore be evaluated in relation to the specific objective or event at hand. Given these guidelines, public as well as individual reactions to hazards and risks can be understood and predicted fairly well. 46 refs, 3 figs

  1. Diagnosis of moderate acute radiation sickness

    Forty patients with malignant lymphoma were given 60Co TLI. 21 cases received 6 Gy and 19 received 8 Gy. It was estimated that a single TLI of 6 and 8 Gy would correspond to TBI of 3.55 Gy and 4.25 Gy (average values) by analysing peripheral blood cell chromosome aberrations and 1.85-2.37 Gy by measuring red bone marrow stem cells clinically. Moderate acute radiation sickness with digestive tract reaction and hemopoietic and immunologic depression was observed. WBC and platelets decreased rapidly. Lymphocytes showed quantitative and qualitative changes even at early stage. All these indexes are significant for diagnosis. Besides, the degree of labial stimulation response, levels of C-reactive protein, corticoid, and urinal nucleoside and alkaloid base presented great changes both pre-and post-irradiation. Early diagnosis of moderate acute radiation sickness could be made in cancer patients subjected to 6-8 Gy TLI

  2. Radiation risk in space exploration

    Humans living and working in space are exposed to energetic charged particle radiation due to galactic cosmic rays and solar particle emissions. In order to keep the risk due to radiation exposure of astronauts below acceptable levels, the physical interaction of these particles with space structures and the biological consequences for crew members need to be understood. Such knowledge is, to a large extent, very sparse when it is available at all. Radiation limits established for space radiation protection purposes are based on extrapolation of risk from Japanese survivor data, and have been found to have large uncertainties. In space, attempting to account for large uncertainties by worst-case design results in excessive costs and accurate risk prediction is essential. It is best developed at ground-based laboratories, using particle accelerator beams to simulate individual components of space radiation. Development of mechanistic models of the action of space radiation is expected to lead to the required improvements in the accuracy of predictions, to optimization of space structures for radiation protection and, eventually, to the development of biological methods of prevention and intervention against radiation injury. (author)

  3. Multiparametric Determination of Radiation Risk

    Richmond, Robert C.

    2003-01-01

    Predicting risk of human cancer following exposure to ionizing space radiation is challenging in part because of uncertainties of low-dose distribution amongst cells, of unknown potentially synergistic effects of microgravity upon cellular protein-expression, and of processing dose-related damage within cells to produce rare and late-appearing malignant transformation, degrade the confidence of cancer risk-estimates. The NASA- specific responsibility to estimate the risks of radiogenic cancer in a limited number of astronauts is not amenable to epidemiologic study, thereby increasing this challenge. Developing adequately sensitive cellular biodosimeters that simultaneously report 1) the quantity of absorbed close after exposure to ionizing radiation, 2) the quality of radiation delivering that dose, and 3) the risk of developing malignant transformation by the cells absorbing that dose could be useful for resolving these challenges. Use of a multiparametric cellular biodosimeter is suggested using analyses of gene-expression and protein-expression whereby large datasets of cellular response to radiation-induced damage are obtained and analyzed for expression-profiles correlated with established end points and molecular markers predictive for cancer-risk. Analytical techniques of genomics and proteomics may be used to establish dose-dependency of multiple gene- and protein- expressions resulting from radiation-induced cellular damage. Furthermore, gene- and protein-expression from cells in microgravity are known to be altered relative to cells grown on the ground at 1g. Therefore, hypotheses are proposed that 1) macromolecular expression caused by radiation-induced damage in cells in microgravity may be different than on the ground, and 2) different patterns of macromolecular expression in microgravity may alter human radiogenic cancer risk relative to radiation exposure on Earth. A new paradigm is accordingly suggested as a national database wherein genomic and

  4. Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

    Chancellor, Jeffery C.; Scott, Graham B. I.; Sutton, Jeffrey P.

    2014-01-01

    Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS) decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop duri...

  5. EVALUATION OF RISK FACTORS IN ACUTE STROKE

    Putta

    2015-03-01

    Full Text Available Introduction: Cerebrovascular disease is the third most common cause of death in the developed world after cancer and ischemic heart disease. In India, community surveys have shown a crude prevalence rate of 200 per 100000 population for hemiplegia. Aims and objectives: Identification of risk factors for c erebrovascular disease. Materials and Methods: Inclusion Criteria: Cases of acute stroke admitted in S.V.R.R.G.G.H, Tirupati were taken for the study. Exclusion Criteria: Head injury cases, neoplasm cases producing cerebrovascular disease were excluded. Re sults: Stroke was more common in male, 54% patients were male 46% were female. It was more common in 6 th and 7 th decade. More common risk factors were hypertension followed by smoking, diabetes mellitus. More common pathology was infarction. Conclusion: Com mon risk factors for acute stroke are hypertension, smoking, diabetes mellitus, alcoholism, obesity, cardiac disease. Stroke was confirmed by CT scan of brain.

  6. Ionizing radiation, genetic risks and radiation protection

    With one method of risk estimation, designed as the doubling dose method, the estimates of total genetic risk (i.e., over all generation) for a population continuously exposed at a rate of 0.01 Gy/generation of low LET irradiation are about 120 cases of Mendelian and chromosomal diseases/106 live births and about the same number of cases for multifactorial diseases (i.e., a total of 240 cases/106). These estimates provide the basis for risk coefficients for genetic effects estimated by ICRP (1991) in its Publication 60. These are: 1.0%/Sv for the general population (which is 40% of 240/106/0.01 Gy), and 0.6%/Sv for radiation workers (which is 60% of that for the general population). The results of genetic studies carried out on the Japanese survivors of A-bombs have shown no significant adverse effects attributable to parental radiation exposures. The studies of Gardner and colleagues suggest that the risk of leukaemia in children born to male workers in the nuclear reprocessing facility in Sellafield, U.K., may be increased. However, this finding is at variance with the results from the Japanese studies and at present, does not lend itself to a simple interpretation based on radiobiological principles. In the light of recent advances in the molecular biology of naturally-occurring human Mendelian diseases and what we presently know about multifactorial diseases, arguments are advanced to support the thesis that (i) current risk estimates for Mendelian diseases may be conservative and (ii) an overall doubling dose for all adverse genetic effects may be higher than the 1 Gy currently used (i.e., the relative risks are probably lower). (author)

  7. Psychological Risk Factors in Acute Leukemia

    Gouva M.

    2009-04-01

    Full Text Available Several theoretical models have been occasionally proposed to account for the involvement of psychological factors in cancer genesis. Family environment and relations as well as certain personality traits were correlated to cancer onset. However, little is known in the case of acute leukemia. The present study examined family environment, state-trait anxiety, hostility and the direction of hostility as well as alexithymia in 41 acute leukemia patients and their first degree relatives (70. In accordance with previous findings, the present results showed that family cohesion, conflict and organization as well as guilt, state anxiety and alexithymia were significant risk factors for the development of the disease.

  8. Radiation risk of diagnostical procedures

    The environmental radiation burden of man in Germany is about 1 mGy (Milligray) per year. This is, of course, also valid for children. Due to diagnostical procedures this burden is increased to about 1.3 mGy. The question arises wether this can be neglected, or important consequences have to be drawn. To give a clear answer, the action of ionizing radiation in living cells and in organisms is explained in detail. Many of the radiation actions at the DNA can soon be repaired by the cell, if the radiation dose was small. Some damage, however will remain irreparable for the cell and consequently leads to cell death, to mutations or to cell transformation. The number of these lesion increases or decreases linearily with radiation dose. Therefore, it must be expected that the risk of tumour induction is increased to above the normal background even by the smallest doses. This small but not negligible risk has to be compared with other risks of civilization or with other medical risks. But also the benefit and the efficacy of diagnostic procedures have to be considered. (orig./HSCH)

  9. On ionising radiation and breast cancer risk

    A cohort of 3,090 women with clinical diagnosis of benign breast disease (BBD) was studied. Of these, 1,216 were treated with radiation therapy during 1925-54 (median age 40 years). The mean dose to the breasts was 5.8 Gy (range 0-50 Gy). Among other organs the lung received the highest scattered dose (0.75 Gy; range 0.004-8.98 Gy) and the rectum the lowest (0.008 Gy; range 0-0.06 Gy). A pooled analysis of eight breast cancer incidence cohorts was done, including: tumour registry data on breast cancer incidence among women in the Life Span Study cohort of atomic bomb survivors; women in Massachusetts who received repeated chest fluoroscopic during lung collapse treatment for tuberculosis; women who received x-ray therapy for acute post-partum mastitis; women who were irradiated in infancy for enlarged thymus glands ; two Swedish cohorts of women who received radiation treatments during infancy for skin hemangioma; and the BBD) cohort. Together the cohorts included almost 78,000 women (-35,000 were exposed), around 1.8 million woman-years and 1500 cases. The breast cancer incidence rate as a function of breast dose was analysed using linear-quadratic Poisson regression models. Cell-killing effects and other modifying effects were incorporated through additional log-linear terms. Additive (EAR) and multiplicative (ERR) models were compared in estimating the age-at-exposure patterns and time related excess. The carcinogenic risks associated with radiation in mammographic mass screening is evaluated. Assessment was made in terms of breast cancer mortality and years of life. Effects were related to rates not influenced by a mammographic mass screening program and based on a hypothetical cohort of 100,000 40-year old women with no history of breast cancer being followed to 100 years of age. Two radiation risk assumptions were compared. The dose-response relationship is linear with little support in data for an upward curvature at low to medium doses. The competing effect

  10. On ionising radiation and breast cancer risk

    Mattson, Anders

    1999-05-01

    A cohort of 3,090 women with clinical diagnosis of benign breast disease (BBD) was studied. Of these, 1,216 were treated with radiation therapy during 1925-54 (median age 40 years). The mean dose to the breasts was 5.8 Gy (range 0-50 Gy). Among other organs the lung received the highest scattered dose (0.75 Gy; range 0.004-8.98 Gy) and the rectum the lowest (0.008 Gy; range 0-0.06 Gy). A pooled analysis of eight breast cancer incidence cohorts was done, including: tumour registry data on breast cancer incidence among women in the Life Span Study cohort of atomic bomb survivors; women in Massachusetts who received repeated chest fluoroscopic during lung collapse treatment for tuberculosis; women who received x-ray therapy for acute post-partum mastitis; women who were irradiated in infancy for enlarged thymus glands ; two Swedish cohorts of women who received radiation treatments during infancy for skin hemangioma; and the BBD cohort. Together the cohorts included almost 78,000 women (-35,000 were exposed), around 1.8 million woman-years and 1500 cases. The breast cancer incidence rate as a function of breast dose was analysed using linear-quadratic Poisson regression models. Cell-killing effects and other modifying effects were incorporated through additional log-linear terms. Additive (EAR) and multiplicative (ERR) models were compared in estimating the age-at-exposure patterns and time related excess. The carcinogenic risks associated with radiation in mammographic mass screening is evaluated. Assessment was made in terms of breast cancer mortality and years of life. Effects were related to rates not influenced by a mammographic mass screening program and based on a hypothetical cohort of 100,000 40-year old women with no history of breast cancer being followed to 100 years of age. Two radiation risk assumptions were compared. The dose-response relationship is linear with little support in data for an upward curvature at low to medium doses. The competing effect

  11. Risks Associated with Ionizing Radiations

    Medical use of ionizing radiations implies certain risks which are widely balanced by their diagnostic and therapeutic benefits. Nevertheless, knowledge about these risks and how to diagnose and prevent them minimizes their disadvantages and optimizes the quality and safety of the method. This article describes the aspects related to skin dose (nonstochastic effects), the importance of dose limit, the physiopathology of biological damage and, finally, the prevention measures.

  12. Radiation treatment of testicular relapse in acute lymphoblastic leukemia

    Ten patients with testicular relapse among 128 cases of acute lymphoblastic leukemia are reported. At the time of the initial diagnosis of leukemia all patients with later testicular relapse showed one or more risk factors as predictive for leukemic infiltration of the testicles. All patients except one, who underwent orchiectomy and died 11 weeks after surgical intervention, received radiation therapy with doses ranging from 12 to 20 Gy and chemotherapy. The local control was excellent. Average survival time from testicular relapse to death was 68 weeks in 8 of 9 patients treated by irradiation and chemotherapy. One patient is still alive without signs of disease after 6 years. (orig.)

  13. Multifocal atherosclerosis in patient after acute first degree radiation sickness.

    Metlyaeva N.A.

    2014-12-01

    Full Text Available Purpose: assessment the heavy psychosomatic and all-somatic cardiovascular and cerebrovascular pathology of patient, transferred an acute I degree radiation sickness, from the general evenly gamma-beta radiation. Conclusions. The subdepressive and disturbing-depressive syndrome of patient, transferred an acute radiation sickness (ARS of I degree, from the general evenly gamma-beta radiation, was independent risk factor of development of multifocal atherosclerosis; Features of development of all-somatic and psychosomatic pathology of patient are based on a combination of genetic prerequisites, environment influences (the stress caused by accident on the ChNPP and social factors, influencing on him during a course of life, especially during early socialization. Thus at development of psychosomatic frustration the combination of feature of the mental reaction connected with the personal characteristic and special relationship between mental (stress and physiological (somatic by aspects of reaction which led to metabolism violation, to aging, decrease in adaptation opportunities of an organism and development age — dependent pathology took place.

  14. Breast carcinogenesis: risk of radiation

    The risk of radiation carcinogenesis in the opposite breast is a major concern for physicians and breast cancer patients who choose to preserve the involved breast through conservation treatment, i.e., conservation survey and radiation therapy. In analyzing the carcinogenic effect of irradiation on the breast, the radiobiologic risks assumed from the studies must be evaluated first in order to determine the accuracy of the epidemiologic data and radiation dosage. It is generally assumed from the carcinogenic studies that radiation is carcinogenic at any dose rate. However, it is well-known that low dose rates are less effective at producing cancer in animal species than high dose rates. However, in most epidemiologic studies no apparent account is taken of dose rate. Also, there are technical differences between the irradiation received by individuals involved in most epidemiologic studies and the therapeutic irradiation received by breast cancer patients. All of these factors make it difficult, if not impossible, to directly correlate the irradiation risk ascertained from the studies and modern radiotherapy. This paper examines what risk exists and how great it is

  15. Radiation risk and science education

    Almost everywhere the topic of radioactivity is taught in the physics or chemistry classes of secondary schools. The question has been raised whether the common approach of teaching this topic would contribute to a better understanding of the risks of ionising radiation: and, if the answer is negative, how to explain and improve this situation? In a Dutch research programme which took almost ten years, answers to this question have been sought by means of analyses of newspaper reports, curriculum development, consultation with radiation experts, physics textbook analysis, interviews and questionnaires with teachers and pupils, class observations and curriculum development. Th main results of this study are presented and some recommendations given for science teaching and for communication with the public in general as regards radiation risk. (author)

  16. Acute toxicity profile of radiotherapy in 690 children and adolescents: RiSK data

    Background and purpose: The 'Registry for the evaluation of side effects after radiation in childhood and adolescence' (risk) was introduced to characterize adverse effects of radiotherapy in childhood and adolescence prospectively. The aim of this analysis was to characterize the pattern of acute side effects. Materials and methods: Since 2001, patients receiving radiotherapy in one of the German pediatric therapy trials have been registered in RiSK with detailed information regarding radiation doses to organs at risk and characterization of acute toxicities. Results: From 2001 to May 2009, 690 patients have been characterized for acute toxicity in primary therapy. Acute toxicity ≥ grade 1 was observed in 506 patients. In patients irradiated in their lung and liver, patients with grade 1 or 2 acute toxicities showed higher organ volumes exposed to radiation doses <20 Gray (Gy) compared to patients without toxicities. For the salivary glands, there was a positive correlation between the acute toxicity grade and the maximum radiation dose to the organ; the lower GI tract showed a similar trend. The impact of different chemotherapy regimens on these acute side effects remains unclear. Age did not have any impact on side effects. Conclusion: This analysis gives a comprehensive overview of the acute toxicities of radiotherapy in children and adolescents. With prolongation of follow-up, detailed analyses regarding late toxicities will be possible with the characterization of dose-volume-effect relationships.

  17. Acute Radiation Syndrome. Consequences and outcomes

    The consequences and outcomes of an Acute Radiation Syndrome (ARS), induced by external gamma radiation for 59 persons (49 men and 10 women) have been estimated. All incidents have taken place more than 40 years ago in the yearly years of adjustment of an atomic industry (1950-1953-38 persons, 1954-1958-21 persons). According to the degree of severity ARS 5 groups are selected: the severest degree - 7 individuals (average dose in group 43.8±12.8 Sv), severe - 4 individuals (9.3±1.5 Sv), medium - 14 individuals (2.2±0.8 Sv), a light degree - 15 individuals (0.93±0.13 Sv), ''erased'' from - 19 individuals (0.85±0.07 Sv). In all cases, except for lethal (the severest degree), the characteristics of morphological composition of the peripheral blood were restored in the first year after ARS and now correspond to physiological standard. In 2 cases the moderate hypoplasia of granulocytopoiesis was diagnosed. A marker of the acute exposure was the chromosome aberrations in lymphocytes of the peripheral blood. The frequency of chromosome aberrations correlates with severity degree of ARS (from 3-7 up to 35-50 stable aberrations per 100 cells). In cases of ARS with severe degree the early development of a cerebral atherosclerosis is detected. The radiation cataract was diagnosed in 5 patients (an exposure doses 4.0-9.8 Sv, a period of development 2-5 years). During the first years after ARS in 80% of cases the complete labour rehabilitation is reached. Of 53 patients with known vital status by 45 year of monitoring 19 persons (35.8%) have died, of these in 2 cases the causes of death are not determined. In remaining cases the causes of death were ARS of severest degree (7 persons), Ischemic Heart Disease (5 persons), malignant tumors (4 persons), accidents and traumas (2 persons). (author)

  18. Acute Radiation Syndrome. Consequences and outcomes

    Okladnikova, N.D.; Pesternikova, V.S.; Sumina, M.V.; Azizova, T.V.; Yurkov, N.N. [Branch No 1 State Research Center of Russia, Ozyorsk (Russian Federation). Inst. of Biophysics

    2000-05-01

    The consequences and outcomes of an Acute Radiation Syndrome (ARS), induced by external gamma radiation for 59 persons (49 men and 10 women) have been estimated. All incidents have taken place more than 40 years ago in the yearly years of adjustment of an atomic industry (1950-1953-38 persons, 1954-1958-21 persons). According to the degree of severity ARS 5 groups are selected: the severest degree - 7 individuals (average dose in group 43.8{+-}12.8 Sv), severe - 4 individuals (9.3{+-}1.5 Sv), medium - 14 individuals (2.2{+-}0.8 Sv), a light degree - 15 individuals (0.93{+-}0.13 Sv), ''erased'' from - 19 individuals (0.85{+-}0.07 Sv). In all cases, except for lethal (the severest degree), the characteristics of morphological composition of the peripheral blood were restored in the first year after ARS and now correspond to physiological standard. In 2 cases the moderate hypoplasia of granulocytopoiesis was diagnosed. A marker of the acute exposure was the chromosome aberrations in lymphocytes of the peripheral blood. The frequency of chromosome aberrations correlates with severity degree of ARS (from 3-7 up to 35-50 stable aberrations per 100 cells). In cases of ARS with severe degree the early development of a cerebral atherosclerosis is detected. The radiation cataract was diagnosed in 5 patients (an exposure doses 4.0-9.8 Sv, a period of development 2-5 years). During the first years after ARS in 80% of cases the complete labour rehabilitation is reached. Of 53 patients with known vital status by 45 year of monitoring 19 persons (35.8%) have died, of these in 2 cases the causes of death are not determined. In remaining cases the causes of death were ARS of severest degree (7 persons), Ischemic Heart Disease (5 persons), malignant tumors (4 persons), accidents and traumas (2 persons). (author)

  19. Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

    Kennedy, Ann; Cengel, Keith

    2012-07-01

    A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

  20. Lung pathology in case of acute radiation injury

    Results of pathomorphological studies of 27 patients exposed to total external γ- and β-radiation resulted from the Chernobyl accident and lost due to the acute radiation disease in the first weeks following radiation exposure are discussed. Dose range is 3.7-13.7 Gy. Two groups of pathological changes in lungs are revealed, those are: infection (bacterial, viral and fungous) ones caused by acute radiation disease and signs of respiratory distress-syndrome in adults

  1. Concept of normalization of random radiation risk

    The possibility for the normal realization in parallel with collective radiation risk and individual risk was considered. Normalization of risk for the individual person, which is exposed to the maximum radiation dose effect, is suggested. It must be kept in mind not only probability of surpassing assigned dose but distribution of number of the specific contingent of the persons by radiation risk, and must define risk of the most irradiated person from this contingent. The impacts of bivariate normalization of risk are illustrated

  2. MRI assessment of local acute radiation syndrome

    Weber-Donat, G.; Potet, J.; Baccialone, J.; Teriitehau, C. [Military Hospital Percy, Radiology Department, Clamart (France); Amabile, J.C.; Laroche, P. [Military Hospital Percy, Army Institute of Radioprotection, Clamart (France); Lahutte-Auboin, M. [Military Hospital Val-de-Grace, Radiology Department, Paris (France); Bey, E. [Military Hospital Percy, Plastic and Reconstructive Surgery Department, Clamart (France)

    2012-12-15

    To describe local acute radiation syndrome and its radiological imaging characteristics. We performed a retrospective study of patients who had suffered skin and deeper radiation damage who were investigated by magnetic resonance imaging (MRI). We compared the clinical findings, C-reactive protein (CRP) levels and MRI results. A total of 22 MRI examinations were performed between 2005 and 2010 in 7 patients; 6 patients had increased CRP levels and MRI abnormalities. They were treated by surgery and local cellular therapy. One patient had no CRP or MRI abnormalities, and had a spontaneous good outcome. Eighteen abnormal MR examinations demonstrated high STIR signal and/or abnormal enhancement in the dermis and muscle tissues. Three MRI examinations demonstrated skeletal abnormalities, consistent with radionecrosis. The four normal MRI examinations were associated only with minor clinical manifestations such as pain and pigmentation disorders. MRI seems to be a useful and promising imaging investigation in radiation burns management i.e. initial lesion evaluation, treatment evaluation and complication diagnosis. MRI findings correlated perfectly with clinical stage and no false negative examinations were obtained. In particular, the association between normal MRI and low CRP level seems to be related to good outcome without specific treatment. (orig.)

  3. MRI assessment of local acute radiation syndrome

    To describe local acute radiation syndrome and its radiological imaging characteristics. We performed a retrospective study of patients who had suffered skin and deeper radiation damage who were investigated by magnetic resonance imaging (MRI). We compared the clinical findings, C-reactive protein (CRP) levels and MRI results. A total of 22 MRI examinations were performed between 2005 and 2010 in 7 patients; 6 patients had increased CRP levels and MRI abnormalities. They were treated by surgery and local cellular therapy. One patient had no CRP or MRI abnormalities, and had a spontaneous good outcome. Eighteen abnormal MR examinations demonstrated high STIR signal and/or abnormal enhancement in the dermis and muscle tissues. Three MRI examinations demonstrated skeletal abnormalities, consistent with radionecrosis. The four normal MRI examinations were associated only with minor clinical manifestations such as pain and pigmentation disorders. MRI seems to be a useful and promising imaging investigation in radiation burns management i.e. initial lesion evaluation, treatment evaluation and complication diagnosis. MRI findings correlated perfectly with clinical stage and no false negative examinations were obtained. In particular, the association between normal MRI and low CRP level seems to be related to good outcome without specific treatment. (orig.)

  4. Medical radiation exposure and genetic risks

    Everyone is exposed to background radiation throughout life (100 mrem/year to the gonads or 4 to 5 rem during the reproductive years). A lumbosacral series might deliver 2500 mrem to the male or 400 mrem to the female gonads. A radiologic procedure is a cost/benefit decision, and genetic risk is a part of the cost. Although cost is usually very low compared to benefit, if the procedure is unnecessary then the cost may be unacceptable. On the basis of current estimates, the doubling dose is assumed to be 40 rem (range 20 to 200) for an acute dose, and 100 rem for protracted exposure. Although there is no satisfactory way to predict the size of the risk for an individual exposed, any risk should be incentive to avoid unnecessary radiation to the gonads. Conception should be delayed for at least ten months for women and three or four months for men after irradiation of the gonads. The current incidence of genetically related diseases in the United States population is 60,000 per million live births. Based on the most conservative set of assumptions, an average gonadal dose of 1000 mrem to the whole population would increase the incidence of genetically related diseases by 0.2%

  5. Pharmacological management of acute radiation morbidity

    Zimmermann, J.S.; Kimmig, B. [Klinik fuer Strahlentherapie (Radioonkologie), Christian-Albrecht-Universitaet Kiel (Germany)

    1998-11-01

    Background: The acute radiation morbidity may be a serious problem for the patient and may be decreased by pharmacological approaches. Material and methods: A database research (Medline, Cancerlit, DIMDI, etc.) was performed in order to obtain pharmacological approaches to decrease the acute radiation morbidity. The evaluation was focused on therapeutic principles but not on special drugs. Results: Different approaches may be chosen to protect healthy tissues from the effects of ionizing radiation: 1. Administration of cyto- or radioprotective agents prior to irradiation, 2. administration of agents to avoid additional secondary toxicity by inflammation or superinfection during the treatment cycle (supportive care) and 3. administration of rescue agents, such as bone marrow CSFs or hyperbaric oxygen (HBO), after therapy. For radioprotection, there are reports on cellular protection by vitamine E, vitamine C, beta carotene, ribose-cysteine, glutamine, Mgcl2/adenosine triphosphate and WR-2721 (amifostine). In general, preclinical studies show that the combination of pretreatment with amifostine, irradiation, and G-CSF after radiation enhances hematologic recovery. Assessment of these combined effects, including local supportive therapies, merits further clinical investigation. There are data from prospective studies as well as from empirical clinical experience, that radioprotection and clinical supportive care may reduce the treatment related morbidity by 10 to 30% either. Conclusions: A further improvement of the therapeutic ratio is to be expected by systemically combined application of radioprotectors, supportive care and rescue agents. (orig.) [Deutsch] Hintergrund: Die strahlentherapeutische Fruehmorbiditaet kann auf das Ergebnis einer Strahlenbehandlung Einfluss nehmen und kann durch medikamentoese Verfahren gelindert werden. Material und Methoden: Eine Datenbankrecherche (Medline, Cancerlit, DIMDI u.a.) wurde durchgefuehrt, um einen Ueberblick ueber

  6. Hematological parameters after acute radiation injury

    According to clinical experiences of radiation accidents during the past two decades, utilization of measured hematologic changes as a direcrt indicator of the severity of radiation injury provides important information for diagnosis and prognostic evaluation in individual cases. Hematologic changes can be described in terms of prognostic categories based on the possible outcome of the acute radiation syndrome. The five categories suggested by Wald according to the grade of severity. By the actual application of this category to our experience of the 1971 Chiba accident of exposure to irridium 192, it was proved that the estimated dose was well correlated to the value by cytogenetic analysis and physical estimation used of thermo-luminescence phenomena. In hematological parameters, a decrease of lymphocytes occurs whithin 24 hours after the exposure. The level of this early lymphopenia is regarded as one of the best indicators of severity of radiation injury. For the decision of therapeutic procedures, however, the total granulocyte count and platelet count are more valuable to exclude severe infection and bleeding symptoms occurred one month after the exposure. The limitation of the approach by hematologic data must exist in the case exposed in a non-uniform fashion. To overwhelm this difficulty, the application of rapid marrow scanning by short-lived RI such as 52Fe is expected and the bone marrow imaging by magnetic resonance studies is more exciting. For more sensitive and technically easy-drived methods detecting hematologic injury, our new method of detecting micro-nucleus in polychromatic erythroblasts from cultured erythroid colonies from peripheral blood is now developing. Preliminary data have shown the sensitivity of this method is comparable to the cytogenetic study of pheripheral lymphocytes. (author)

  7. What Are the Risk Factors for Acute Lymphocytic Leukemia?

    ... both ALL and acute myeloid leukemia (AML). Japanese atomic bomb survivors had a greatly increased risk of developing ... cell acute lymphocytic leukemia. Most cases occur in Japan and the Caribbean area. This disease is not ...

  8. Mesenchymal stem cell therapy for acute radiation syndrome.

    Fukumoto, Risaku

    2016-01-01

    Acute radiation syndrome affects military personnel and civilians following the uncontrolled dispersal of radiation, such as that caused by detonation of nuclear devices and inappropriate medical treatments. Therefore, there is a growing need for medical interventions that facilitate the improved recovery of victims and patients. One promising approach may be cell therapy, which, when appropriately implemented, may facilitate recovery from whole body injuries. This editorial highlights the current knowledge regarding the use of mesenchymal stem cells for the treatment of acute radiation syndrome, the benefits and limitations of which are under investigation. Establishing successful therapies for acute radiation syndrome may require using such a therapeutic approach in addition to conventional approaches. PMID:27182446

  9. Perinatal risk factors for acute myeloid leukemia.

    Crump, Casey; Sundquist, Jan; Sieh, Weiva; Winkleby, Marilyn A; Sundquist, Kristina

    2015-12-01

    Infectious etiologies have been hypothesized for acute leukemias because of their high incidence in early childhood, but have seldom been examined for acute myeloid leukemia (AML). We conducted the first large cohort study to examine perinatal factors including season of birth, a proxy for perinatal infectious exposures, and risk of AML in childhood through young adulthood. A national cohort of 3,569,333 persons without Down syndrome who were born in Sweden in 1973-2008 were followed up for AML incidence through 2010 (maximum age 38 years). There were 315 AML cases in 69.7 million person-years of follow-up. We found a sinusoidal pattern in AML risk by season of birth (P birth order, parental age, and parental country of birth were not associated with AML. In this large cohort study, birth in winter was associated with increased risk of AML in childhood through young adulthood, possibly related to immunologic effects of early infectious exposures compared with summer birth. These findings warrant further investigation of the role of seasonally varying perinatal exposures in the etiology of AML. PMID:26113060

  10. Risk assessment of radiation carcinogenesis

    This commentary describes the radiation cancer risk assessed by international organizations other than ICRP, assessed for radon and for internal exposure, in the series from the aspect of radiation protection of explaining the assessments done until ICRP Pub. 103. Statistic significant increase of cancer formation is proved at higher doses than 100-200 mSv. At lower doses, with use of mathematical model, United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reported the death probability due to the excess lifetime risk (ELR) at 100 mSv of 0.36-0.77% for solid tumors and 0.03-0.05% for leukemia, and NRC in US, the risk of exposure-induced prevalence and death (REID) per 100 thousands persons of 800 (male)/1,310 (female) and 410/610, respectively. Both are essentially based on findings in A-bomb survivors. The assessment for Rn is described here not on dose. UK and US analyses of pooled raw data in case control studies revealed the significant increase of lung cancer formation at as low level as 100 Bq Rn/m3. Their analyses also showed the significance of smoking, which had been realized as a confounding factor in risk analysis of Rn for uranium miners. The death probability until the age of 85 y was found to be 1.2 x 10-4 in non-smokers and 24 x 10-4 in smokers/ Working Level Month (WLM). Increased thyroid cancer incidence has been known in Chernobyl Accident, which is realized as a result of internal exposure of radioiodine; however, the relationship between the internal dose to thyroid and its cancer prevalence resembles that in the case of external exposure. There is no certain evidence against the concept that risk of internal exposure is similar to and/or lower than, the external one although assessment of the internal exposure risk accompanies uncertainty depending on the used model and ingested dose. International Commission on Radiological Protection (ICRP) recommendations hitherto have been important and precious despite

  11. Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy

    Bray, Fleta N.; Simmons, Brian J.; Aaron H. Wolfson; Nouri, Keyvan

    2016-01-01

    Ionizing radiation is an important treatment modality for a variety of malignant conditions. However, development of radiation-induced skin changes is a significant adverse effect of radiation therapy (RT). Cutaneous repercussions of RT vary considerably in severity, course, and prognosis. When they do occur, cutaneous changes to RT are commonly graded as acute, consequential-late, or chronic. Acute reactions can have severe sequelae that impact quality of life as well as cancer treatment. Th...

  12. Acute radiation nephritis. Its evolution on sequential bone imaging

    Acute radiation nephritis typically affects the kidneys 3-12 months after radiation exposure and may occur with doses as low as 2500 rads. After an initial latent period, the affected portions of the kidneys become swollen and edematous, and develop multiple petechiae. Necrotizing vasculitis and interstitial hemorrhage occur, and the end stage is that of scarring. Two patients are presented in whom localized acute radiation nephritis developed, and whose kidneys demonstrated the characteristic sequential changes of this entity on serial bone imaging

  13. Radiation risks and radiation protection at CRNL

    Radiation exposure is an occupational hazard at CRNL. The predicted health effects of low levels of radiation are described and compared with other hazards of living. Data related to the health of radiation workers are also considered. Special attention is given to the expected effects of radiation on the unborn child. Measures taken to protect CRNL employees against undue occupational exposure to radiation are noted

  14. Explanation of nurse standard of external exposure acute radiation sickness

    National occupational health standard-Nurse Standard of External Exposure Acute Radiation Sickness has been approved and issued by the Ministry of Health. Based on the extensive research of literature, collection of the previous nuclear and radiation accidents excessive exposed personnel data and specific situations in China, this standard was enacted according to the current national laws, regulations, and the opinions of peer experts. It is mainly used for care of patients with acute radiation sickness, and also has directive significance for care of patients with iatrogenic acute radiation sickness which due to the hematopoietic stem cell transplantation pretreatment. To correctly carry out this standard and to reasonably implement nursing measures for patients with acute radiation sickness, the contents of this standard were interpreted in this article. (authors)

  15. Space radiation risks to the central nervous system

    Cucinotta, Francis A.; Alp, Murat; Sulzman, Frank M.; Wang, Minli

    2014-07-01

    Central nervous system (CNS) risks which include during space missions and lifetime risks due to space radiation exposure are of concern for long-term exploration missions to Mars or other destinations. Possible CNS risks during a mission are altered cognitive function, including detriments in short-term memory, reduced motor function, and behavioral changes, which may affect performance and human health. The late CNS risks are possible neurological disorders such as premature aging, and Alzheimer's disease (AD) or other dementia. Radiation safety requirements are intended to prevent all clinically significant acute risks. However the definition of clinically significant CNS risks and their dependences on dose, dose-rate and radiation quality is poorly understood at this time. For late CNS effects such as increased risk of AD, the occurrence of the disease is fatal with mean time from diagnosis of early stage AD to death about 8 years. Therefore if AD risk or other late CNS risks from space radiation occur at mission relevant doses, they would naturally be included in the overall acceptable risk of exposure induced death (REID) probability for space missions. Important progress has been made in understanding CNS risks due to space radiation exposure, however in general the doses used in experimental studies have been much higher than the annual galactic cosmic ray (GCR) dose (∼0.1 Gy/y at solar maximum and ∼0.2 Gy/y at solar minimum with less than 50% from HZE particles). In this report we summarize recent space radiobiology studies of CNS effects from particle accelerators simulating space radiation using experimental models, and make a critical assessment of their relevance relative to doses and dose-rates to be incurred on a Mars mission. Prospects for understanding dose, dose-rate and radiation quality dependencies of CNS effects and extrapolation to human risk assessments are described.

  16. Radiation risks for pregnant women

    This brief survey makes evident that in all of the commonly used radiographic or radionuclide examinations the radiation dose received by the embryo/fetus remains far below the 50 mGy tolerance threshold set for the ovaries, beyond which the occurrence of intrauterine damage cannot be entirely ruled out. The range of radiography and radionuclide procedures involving exposure to an ovarian dose in excess of 1 mGy is restricted to such examinations as abdominal angiography, contrast-enhanced visualisation of the colon or scintiscanning of cardiac and skeletal structures. If sufficient caution is observed, the embryonic/fetal risk from carefully chosen radiologic or radionuclide techniques remains within reasonably acceptable limits. Considering the risks inherent in any gestational process, the probability of defective development or even death of the embryo/fetus is described as increased only for the radiotherapeutic dose range. (orig./MG)

  17. Radiation teratogenesis: fetal risk and abortion

    The effects of radiation on the developing mammalian embryo and especially the human embryo are reviewed. Counseling the women of reproductive age who will be exposed to radiation or have been exposed to radiation is frequently performed by physicians in a cavalies fashion, without the benefit of knowing the radiation exposure or the risks. The patient should be made aware of the radiation hazards to the embryos by individuals who are knowledgeable. Human radiation teratogenesis is described

  18. Evaluations of Risks from the Lunar and Mars Radiation Environments

    Kim, Myung-Hee; Hayat, Matthew J.; Feiveson, Alan H.; Cucinotta, Francis A.

    2008-01-01

    Protecting astronauts from the space radiation environments requires accurate projections of radiation in future space missions. Characterization of the ionizing radiation environment is challenging because the interplanetary plasma and radiation fields are modulated by solar disturbances and the radiation doses received by astronauts in interplanetary space are likewise influenced. The galactic cosmic radiation (GCR) flux for the next solar cycle was estimated as a function of interplanetary deceleration potential, which has been derived from GCR flux and Climax neutron monitor rate measurements over the last 4 decades. For the chaotic nature of solar particle event (SPE) occurrence, the mean frequency of SPE at any given proton fluence threshold during a defined mission duration was obtained from a Poisson process model using proton fluence measurements of SPEs during the past 5 solar cycles (19-23). Analytic energy spectra of 34 historically large SPEs were constructed over broad energy ranges extending to GeV. Using an integrated space radiation model (which includes the transport codes HZETRN [1] and BRYNTRN [2], and the quantum nuclear interaction model QMSFRG[3]), the propagation and interaction properties of the energetic nucleons through various media were predicted. Risk assessment from GCR and SPE was evaluated at the specific organs inside a typical spacecraft using CAM [4] model. The representative risk level at each event size and their standard deviation were obtained from the analysis of 34 SPEs. Risks from different event sizes and their frequency of occurrences in a specified mission period were evaluated for the concern of acute health effects especially during extra-vehicular activities (EVA). The results will be useful for the development of an integrated strategy of optimizing radiation protection on the lunar and Mars missions. Keywords: Space Radiation Environments; Galactic Cosmic Radiation; Solar Particle Event; Radiation Risk; Risk

  19. Electronical recording and evaluation of acute radiation morbidity

    Background: Relatively uniform documentation systems are used for recording of acute side effects in oncology. Object of this work is to illustrate the applicability of electronic data bases for registration and evaluation of acute side effects in radiation therapy. Methods: Based on topographic documentation sheets, an electronic data base was developed for each major topographic site. Besides general patient related parameters (TNM, previous chemotherapy, surgical interventions, intercurrent diseases and more), the kind and the degree of acute radiation related side effects are documented for each week of radiation and for day 90 (RTOG) as the joint day between acute and subacute tissue reactions. Results: The temporal expenditure for the recording of the general patient related parameters of a patient is less than a minute. The weekly documentation can be performed during the daily routine work and needs approximately 5 minutes per week. The structure of the data base enables later analyses of acute radiation related morbidity. Conclusions: Electronic data bases enable a fast and systematic recording and evaluation of acute radiation related side effects. The development of particular registration entities for recording of acute side effects may be a possible application and demonstrates the needs of professional developments. (orig.)

  20. Cancer risk as a radiation detriment

    Potential radiation detriment means a risk of cancer or other somatic disease, genetic damage of fetal injury. Quantative information about the relation between a radiation dose and cancer risk is needed to enable decision-making in radiation protection. However, assessment of cancer risk by means of the radiation dose is controversial, as epidemiological and biological information about factors affecting the origin of cancers show that risk assessment is imprecise when the radiation dose is used as the only factor. Focusing on radiation risk estimates for breast cancer, lung cancer and leukemia, the report is based on the models given in the Beir V report, on sources of radiation exposure and the uncertainty of risk estimates. Risk estimates are assessed using the relative risk model and the cancer mortality rates in Finland. Cancer incidence and mortality rates for men and women are shown in graphs as a function of age and time. Relative risks are shown as a function of time after exposure and lifetime risks as a function of age at exposure. Uncertainty factors affecting the radiation risk are examined from the point of view of epidemiology and molecular biology. (orig.)

  1. Involvement of Toll-like receptors in acute radiation syndrome and radiation therapy for cancer

    Toll-like receptors (TLR) are one of pattern recognition receptors that are indispensable for antibacterial and antiviral immunity. After TLRs sense pathogen-derived components, they activate intracellular signaling pathways, which results in the induction of proinflammatory cytokines. Although it is well known that radiation therapy is one of effective cancer therapies, radiation affects immune system. Recent evidences show the involvement of TLR in acute radiation syndrome and radiation therapy for cancer. I summarize to date knowledge on the involvement of Toll-like receptors in acute radiation syndromes and radiation therapy for cancer, and discuss the effects of ionizing radiation on TLR of innate immune cells. (author)

  2. Radiation risk perception in Institute 'Vinca'

    The necessity for research and development of risk analysis methods arise from practical needs for safety for men and environment. Relating to speed of technological development risk is implemented in modern technological achievements. Complexity of approach to the concept of risk presents the essence of risk management. Risk management means to apply risk analysis in order to risk decrease and control. Database for risk management is in technical social, economic and political area. Risk perception is a construction in the field of social psychology i.e. public opinion research. These results are of importance for the risk management. Research presented in this paper has been done on the sample of 240 examines with two basic sub samples: person working with ionizing radiation (140 of them) and persons not working with ionizing radiation (100 of them). Attitudes to risk definition risk acceptance and relation to risk consequences. (author)

  3. Acute radiation proctitis. A clinical, histopathological and histochemical study

    Hovdenak, Nils

    2004-07-01

    The aim of the study is: 1) A sequential description of the clinical course of acute radiation proctitis during pelvic RT. 2) A sequential description of the rectal mucosal histopathology during pelvic RT as a possible substrate for clinical toxicity. 3) To assess the mucosal protease activity during RT as a possible explanation of the observed tissue changes. 4) To assess the efficacy of prophylactic sucralfate in acute radiation proctitis a randomised study was initiated and carried out together with a meta-analysis of previously available data. 5) Most studies on clinical acute toxicity in pelvic RT use either the RTOG/EORTC score system or focus on diarrhoea/stool frequency. A more differentiated and sensitive recording was developed and tested to pick up symptoms escaping the commonly used scores. 6) Study the relation between histopathological findings and the clinical picture. 4 papers presenting various studies are included. The titles are: 1) Acute radiation proctitis: a sequential clinicopathologic study during pelvic radiotherapy. 2) Clinical significance of increased gelatinolytic activity in the rectal mucosa during external beam radiation therapy of prostate cancer. 3) Profiles and time course of acute radiation toxicity symptoms during conformal radiotherapy for cancer of the prostate. 4) Sucralfate does not ameliorate acute radiation proctitis. Some future prospects are discussed.

  4. Acute radiation proctitis. A clinical, histopathological and histochemical study

    The aim of the study is: 1) A sequential description of the clinical course of acute radiation proctitis during pelvic RT. 2) A sequential description of the rectal mucosal histopathology during pelvic RT as a possible substrate for clinical toxicity. 3) To assess the mucosal protease activity during RT as a possible explanation of the observed tissue changes. 4) To assess the efficacy of prophylactic sucralfate in acute radiation proctitis a randomised study was initiated and carried out together with a meta-analysis of previously available data. 5) Most studies on clinical acute toxicity in pelvic RT use either the RTOG/EORTC score system or focus on diarrhoea/stool frequency. A more differentiated and sensitive recording was developed and tested to pick up symptoms escaping the commonly used scores. 6) Study the relation between histopathological findings and the clinical picture. 4 papers presenting various studies are included. The titles are: 1) Acute radiation proctitis: a sequential clinicopathologic study during pelvic radiotherapy. 2) Clinical significance of increased gelatinolytic activity in the rectal mucosa during external beam radiation therapy of prostate cancer. 3) Profiles and time course of acute radiation toxicity symptoms during conformal radiotherapy for cancer of the prostate. 4) Sucralfate does not ameliorate acute radiation proctitis. Some future prospects are discussed

  5. Probabilistic methodology for estimating radiation-induced cancer risk

    The RICRAC computer code was developed at Oak Ridge National Laboratory to provide a versatile and convenient methodology for radiation risk assessment. The code allows as input essentially any dose pattern commonly encountered in risk assessments for either acute or chronic exposures, and it includes consideration of the age structure of the exposed population. Results produced by the analysis include the probability of one or more radiation-induced cancer deaths in a specified population, expected numbers of deaths, and expected years of life lost as a result of premature fatalities. These calculatons include consideration of competing risks of death from all other causes. The program also generates a probability frequency distribution of the expected number of cancers in any specified cohort resulting from a given radiation dose. The methods may be applied to any specified population and dose scenario

  6. Practical risk management in radiation therapy

    Technology advances in radiation therapy is very remarkable. In the technological progress of radiation therapy, development of computer control technology has helped. However, there is no significant progress in the ability of human beings who is operating. In many hospitals, by the incorrect parameter setting and wrong operations at radiation treatment planning system, many incidents have been reported recently. In order to safely use invisible radiation beam for treatment, what we should be careful? In state-of-the-art radiation therapy and many technological progress, risk management should be correspond continue. I report practical risk management in radiation therapy about the technical skills, non-technical skills and the quality control. (author)

  7. Radiation-induced acute myeloid leukaemia in mice

    Ample epidemiological studies of human populations implicate ionizing radiation as a carcinogen and these quantitative studies provide the foundation for the core estimates of radiation cancer risk. The majority of the epidemiological data originate from situations of radiation exposure at high dose and high dose rate. The relevance of risk estimates based on such exposures to the more commonly encountered low dose and dose rate situation has been questioned frequently. Thus, there is a need to investigate and quantitate low dose and dose rate effects. A number of approaches may be considered, for example, very large scale epidemiology, very large scale animal experimentation; however, both of these present problems of a practical and/or ethical nature. A further possible approach is that of mechanistic modelling. This requires a fairly detailed understanding of neoplastic disease and how it develops post-irradiation. Many factors and variables have to be taken into consideration in mechanistic modelling approaches. Testing of mechanistic modelling schemes is best carried out using animal model systems. Acute myeloid leukaemia (AML) is a radiogenic cancer of significance in man and several good mouse models of the disease are available. Here, recent studies conducted at NRPB with the aim of elucidating the post-irradiation development of AML will be discussed. In particular three areas critical for developing a sound mechanistic model will be covered, definition of the initiating event; study of disease progression, this addresses the question of the frequency of conversion of initiated cells into the neoplastic state and the influence of genetic background on leukaemogenesis. (author)

  8. Assessment of risk from radiation sources

    Assessment of risk from exposure to ionizing radiations from man-made radiation sources and nuclear installations has to be viewed from three aspects, namely, dose-effect relationship (genetic and somatic) for humans, calculation of doses or dose-commitments to population groups, assessment of risk to radiation workers and the population at large from the current levels of exposure from nuclear industry and comparison of risk estimates with other industries in a modern society. These aspects are discussed in brief. On the basis of available data, it is shown that estimated incidence of genetic diseases and cancers due to exposure of population to radiation from nuclear industry is negligible in comparison with their natural incidence, and radiation risks to the workers in nuclear industry are much lower than the risks in other occupations. (M.G.B.)

  9. Risk and benefits in ionizing radiation uses

    This meeting include: A tribute to Szeinfeld, presentation software for population dose, impact on radiation protection, radiation protection hospital and population exposed workers, regulation and licensing. radiological emergencies, risk, inspection, external radiotherapy and radiation protection with photons, brachytherapy, industrial, environmental monitoring, food irradiation, nuclear power, nuclear medicine.

  10. Radiation effects and radiation risks. 2. ed.

    The book presents the facts and the principles of assessment and evaluation of biological radiation effects in general and also with particular reference to the reactor accident of Chernobyl, reviewing the consequences and the environmental situation on the basis of current national and international literature, including research work by the authors. The material compiled in this book is intended especially for physicians, but will also prove useful for persons working in the public health services, in administration, or other services taking care of people. The authors tried to find an easily comprehensible way of presenting and explaining the very complex processes and mechanisms of biological radiation effects and carcinogenesis, displaying the physical primary processes and the mechanisms of the molecular radiation effects up to the effects of low-level radiation, and present results of comparative epidemiologic studies. This section has been given considerable space, in proportion to its significance. It also contains literature references for further reading, offering more insight and knowledge of aspects of special subject fields. The authors also present less known results and data and discuss them against the background of well-known research results and approaches. Apart from the purpose of presenting comprehensive information, the authors intend to give an impact for further thinking about the problems, and helpful tools for independent decisions and action on the basis of improved insight and assessment, and in this context particularly point to the problems induced by the Chernobyl reactor accident. (orig.) With 10 maps in appendix

  11. Relations between radiation risks and radiation protection measuring techniques

    Relations between radiation risks and radiation protection measuring techniques are considered as components of the radiation risk. The influence of the exposure risk on type and extent of radiation protection measurements is discussed with regard to different measuring tasks. Based upon measuring results concerning the frequency of certain external and internal occupational exposures in the GDR, it has been shown that only a small fraction of the monitored persons are subjected to a high exposure risk. As a consequence the following recommendations are presented: occupationally exposed persons with small exposure risk should be monitored using only a long-term desimeter (for instance a thermoluminescence desimeter). In the case of internal exposure, the surface and air contamination levels should be controlled so strictly that routine measurements of internal contamination need not be performed

  12. Radiation risk in mammography examinations

    The application of X rays in mammography examinations requires not only constant control of physical and technical parameters of the equipment used, but also an evaluation of the radiation risk for patients, particularly in mammography screening programmes. There are a number of methods of dose evaluation in mammography. Some of them are included in the dosimetry protocols. The tolerances for measured values, limiting the dose to the patients have also been established. One of the methods, proposed by Dance, applies to establishing the doses to individual patients. It requires the knowledge of clinical and exposure parameters. Another method, recommended by the EC, requires establishing the phantom dose for reference exposure, as part of quality control tests. This approach is simpler but less precise, because at most mammography facilities, the conditions of reference exposure are different than those of routine clinical exposure, as was shown in an exercise of quality control tests in a group of 32 mammography facilities in Poland. The method proposed in this study is an intermediate solution recommending measurement of the phantom dose for routine clinical exposure. The report contains the data of 230 exposures performed at six mammography facilities in Poland. These data were used to establish an individual dose for every patient undergoing mammography examination according to the method proposed by Dance. For each mammography facility, the mean glandular dose (MGDF) was established for reference and routine exposures according to the EC Dosimetry Protocol. The limits for phantom dose were established, which, according to the EC protocol, depend on the optical density (over background) of the image of the PMMA phantom 4.5 cm thick. The phantom doses determined for each mammography facility were below the limits. The lowest value of the mean dose received by patients in six facilities was 1.05 mGy, and the highest 3.03 mGy. The differences between these values

  13. Space radiation and cardiovascular disease risk.

    Boerma, Marjan; Nelson, Gregory A; Sridharan, Vijayalakshmi; Mao, Xiao-Wen; Koturbash, Igor; Hauer-Jensen, Martin

    2015-12-26

    Future long-distance space missions will be associated with significant exposures to ionizing radiation, and the health risks of these radiation exposures during manned missions need to be assessed. Recent Earth-based epidemiological studies in survivors of atomic bombs and after occupational and medical low dose radiation exposures have indicated that the cardiovascular system may be more sensitive to ionizing radiation than was previously thought. This has raised the concern of a cardiovascular disease risk from exposure to space radiation during long-distance space travel. Ground-based studies with animal and cell culture models play an important role in estimating health risks from space radiation exposure. Charged particle space radiation has dense ionization characteristics and may induce unique biological responses, appropriate simulation of the space radiation environment and careful consideration of the choice of the experimental model are critical. Recent studies have addressed cardiovascular effects of space radiation using such models and provided first results that aid in estimating cardiovascular disease risk, and several other studies are ongoing. Moreover, astronauts could potentially be administered pharmacological countermeasures against adverse effects of space radiation, and research is focused on the development of such compounds. Because the cardiovascular response to space radiation has not yet been clearly defined, the identification of potential pharmacological countermeasures against cardiovascular effects is still in its infancy. PMID:26730293

  14. Radiation risk and public education

    Two issues which deal with the public's perception of radiation hazards are discussed. The goal of public education about radiation, and the relative role of scientific and moral beliefs in public education are examined

  15. Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy.

    Bray, Fleta N; Simmons, Brian J; Wolfson, Aaron H; Nouri, Keyvan

    2016-06-01

    Ionizing radiation is an important treatment modality for a variety of malignant conditions. However, development of radiation-induced skin changes is a significant adverse effect of radiation therapy (RT). Cutaneous repercussions of RT vary considerably in severity, course, and prognosis. When they do occur, cutaneous changes to RT are commonly graded as acute, consequential-late, or chronic. Acute reactions can have severe sequelae that impact quality of life as well as cancer treatment. Thus, dermatologists should be informed about these adverse reactions, know how to assess their severity and be able to determine course of management. The majority of measures currently available to prevent these acute reactions are proper skin hygiene and topical steroids, which limit the severity and decrease symptoms. Once acute cutaneous reactions develop, they are treated according to their severity. Treatments are similar to those used in prevention, but incorporate wound care management that maintains a moist environment to hasten recovery. Chronic changes are a unique subset of adverse reactions to RT that may develop months to years following treatment. Chronic radiation dermatitis is often permanent, progressive, and potentially irreversible with substantial impact on quality of life. Here, we also review the etiology, clinical manifestations, pathogenesis, prevention, and management of late-stage cutaneous reactions to radiotherapy, including chronic radiation dermatitis and radiation-induced fibrosis. PMID:27250839

  16. Perioperative aspirin and clonidine and risk of acute kidney injury

    Garg, Amit X; Kurz, Andrea; Sessler, Daniel I;

    2014-01-01

    IMPORTANCE: Acute kidney injury, a common complication of surgery, is associated with poor outcomes and high health care costs. Some studies suggest aspirin or clonidine administered during the perioperative period reduces the risk of acute kidney injury; however, these effects are uncertain and ...

  17. Radiation protection standards: A practical exercise in risk assessment

    Within 12 months of the discovery of x-rays in 1895, it was reported that large doses of radiation were harmful to living human tissues. The first radiation protection standards were set to avoid the early effects of acute irradiation. By the 1950s, evidence was mounting for late somatic effects - mainly a small excess of cancers - in irradiated populations. In the late 1980's, sufficient human epidemiological data had been accumulated to allow a comprehensive assessment of carcinogenic radiation risks following the delivery of moderately high doses. Workers and the public are exposed to lower doses and dose-rates than the groups from whom good data are available so that risks have had to be estimated for protection purposes. However, in the 1990s, some confirmation of these risk factors has been derived occupationally exposed populations. If an estimate is made of the risk per unit dose, then in order to set dose limits, an unacceptable level of risk must be established for both workers and the public. There has been and continues to be a debate about the definitions of 'acceptable' and 'tolerable' and the attributing of numerical values to these definitions. This paper discusses the issues involved in the quantification of these terms and their application to setting dose limits on risk grounds. Conclusions are drawn about the present protection standards and the application of the methods to other fields of risk assessment. (author)

  18. Characterising risk - aggregated metrics: radiation and noise

    The characterisation of risk is an important phase in the risk assessment - risk management process. From the multitude of risk attributes a few have to be selected to obtain a risk characteristic or profile that is useful for risk management decisions and implementation of protective measures. One way to reduce the number of attributes is aggregation. In the field of radiation protection such an aggregated metric is firmly established: effective dose. For protection against environmental noise the Health Council of the Netherlands recently proposed a set of aggregated metrics for noise annoyance and sleep disturbance. The presentation will discuss similarities and differences between these two metrics and practical limitations. The effective dose has proven its usefulness in designing radiation protection measures, which are related to the level of risk associated with the radiation practice in question, given that implicit judgements on radiation induced health effects are accepted. However, as the metric does not take into account the nature of radiation practice, it is less useful in policy discussions on the benefits and harm of radiation practices. With respect to the noise exposure metric, only one effect is targeted (annoyance), and the differences between sources are explicitly taken into account. This should make the metric useful in policy discussions with respect to physical planning and siting problems. The metric proposed has only significance on a population level, and can not be used as a predictor for individual risk. (author)

  19. Stem cell-based therapies for acute radiation syndrome

    Exposure to high doses of ionizing radiation in the event of accidental or intentional incident such as nuclear/radiological terrorism can lead to debilitating injuries to multiple organs resulting in death within days depending on the amount of radiation dose and the quality of radiation. Unfortunately, there is not a single FDA-licensed drug approved against acute radiation injury. The RadStem Center for Medical Countermeasures against Radiation (RadStem CMGR) program at Einstein is developing stem cell-based therapies to treat acute radiation syndrome (ARS). We have demonstrated that intravenous transplantation of bone marrow-derived and adipose-derived stromal cells, consisting of a mixture of mesenchymal, endothelial and myeloid progenitors can mitigate mice exposed to whole body irradiation of 12 Gy or whole abdominal irradiation of up to 20 Gy. We identified a variety of growth and differentiation factors that individually is unable to improve survival of animals exposed to lethal irradiation, but when administered sequentially mitigates radiation injury and improves survival. We termed this phenomenon as synthetic survival and describe a new paradigm whereby the 'synthetic survival' of irradiated tissues can be promoted by systemic administration of growth factors to amplify residual stem cell clonogens post-radiation exposure, followed by a differentiation factor that favors tissue stem cell differentiation. Synthetic survival can be applied to mitigate lethal radiation injury in multiple organs following radiation-induced hematopoeitic, gastrointestinal and pulmonary syndromes. (author)

  20. Delineating organs at risk in radiation therapy

    Cèfaro, Giampiero Ausili; Perez, Carlos A

    2014-01-01

    Defining organs at risk is a crucial task for radiation oncologists when aiming to optimize the benefit of radiation therapy, with delivery of the maximum dose to the tumor volume while sparing healthy tissues. This book will prove an invaluable guide to the delineation of organs at risk of toxicity in patients undergoing radiotherapy. The first and second sections address the anatomy of organs at risk, discuss the pathophysiology of radiation-induced damage, and present dose constraints and methods for target volume delineation. The third section is devoted to the radiological anatomy of orga

  1. Effects of Ozonated Olive Oil on Acute Radiation Proctitis in Rats

    Gültekin, Fatma Ayça; BAKKAL, Bekir Hakan; Sümer, Demet; Köktürk, Füruzan; Bektaş, Sibel

    2013-01-01

    Background: Acute radiation proctitis is a common complication of pelvic radiation and management of acute radiation proctitis is under evaluation. The beneficial effects of ozonated olive oil (OzOO) have already been shown in the treatment of chronic wounds. Thus, this study was designed to evaluate the therapeutic effects of topical OzOO on acute radiation proctitis. Aims: To evaluate the therapeutic effects of topical OzOO on acute radiation proctitis. Study Design: An...

  2. New radiobiological, radiation risk and radiation protection paradigms

    The long-standing conventional paradigm for radiobiology has formed a logical basis for the standard paradigm for radiation risk of cancer and heritable effects and, from these paradigms, has developed the internationally applied system for radiation protection, but with many simplifications, assumptions and generalizations. A variety of additional radiobiological phenomena that do not conform to the standard paradigm for radiobiology may have potential implications for radiation risk and radiation protection. It is suggested, however, that the current state of knowledge is still insufficient for these phenomena, individually or collectively, to be formulated systematically into a new paradigm for radiobiology. Additionally, there is at present lack of direct evidence of their relevance to risk for human health, despite attractive hypotheses as to how they might be involved. Finally, it remains to be shown how incorporation of such phenomena into the paradigm for radiation protection would provide sufficient added value to offset disruption to the present widely applied system. Further research should aim for better mechanistic understanding of processes such as radiation-induced genomic instability (for all radiation types) and bystander effects (particularly for low-fluence high-LET particles) and also priority should be given to confirmation, or negation, of the relevance of the processes to human health risks from radiation.

  3. Radiation therapy treatment of acute refractory renal allograft rejection

    radiation treatment (median 4, range 1-22), number of transplants (one transplant in 77 %), and concomitant immunosuppressive therapy. Independent factors by the Cox regression model were: Sex (P=0.005), Creatinine levels (P=0.000), HLA-DR (P=0.05), PRA-Max > 70% (P=0.014). Each factor was scored using the integral coefficients to generate four different groups. The overall actuarial graft survival from the initiation of RT was 83% at 1 month, 60% at 1 year and 36% at 5 years. The Kaplan-Meier survival analyzed by groups seems to produce an interpretable separation of the risk factors for graft loss. The number of rejections of pre-RT range from 1-6 (median 2) and post-RT range from 0-3 (median 0). Conclusions: Our experience indicates that radiation therapy provides effective treatment for acute refractory renal allograft rejection. The response to radiation therapy in patients treated with acute refractory renal graft rejection can be predicted by a new scoring system

  4. Acute Cerebrovascular Radiation Syndrome: Radiation Neurotoxicity , mechanisms of CNS radiation injury, advanced countermeasures for Radiation Protection of Central Nervous System.

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key words: Cerebrovascular Acute Radiation Syndrome (Cv ARS), Radiation Neurotoxins (RNT), Neurotransmitters, Radiation Countermeasures, Antiradiation Vaccine (ArV), Antiradiation Blocking Antibodies, Antiradiation Antidote. Psychoneuroimmunology, Neurotoxicity. ABSTRACT: To review the role of Radiation Neurotoxins in triggering, developing of radiation induced central nervous system injury. Radiation Neurotoxins - rapidly acting blood toxic lethal agent, which activated after irradiation and concentrated, circulated in interstitial fluid, lymph, blood with interactions with cell membranes, receptors and cell compartments. Radiation Neurotoxins - biological molecules with high enzymatic activity and/or specific lipids and activated or modified after irradiation. The Radiation Neurotoxins induce increased permeability of blood vessels, disruption of the blood-brain barrier, blood-cerebrospinal fluid (CSF) barrier and developing severe disorder of blood macro- and micro-circulation. Principles of Radiation Psychoneuro-immunology and Psychoneuro-allergology were applied for determination of pathological processes developed after irradiation or selective administration of Radiation Neurotoxins to radiation naïve mammals. Effects of radiation and exposure to radiation can develop severe irreversible abnormalities of Central Nervous System, brain structures and functions. Antiradiation Vaccine - most effective, advanced methods of protection, prevention, mitigation and treatment and was used for of Acute Radiation Syndromes and elaboration of new technology for immune-prophylaxis and immune-protection against ϒ, Heavy Ion, Neutron irradiation. Results of experiments suggested that blocking, antitoxic, antiradiation antibodies can significantly reduce toxicity of Radiation Toxins. New advanced technology include active immune-prophylaxis with Antiradiation Vaccine and Antiradiation therapy that included specific blocking antibodies to Radiation Neurotoxins

  5. Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy.

    Hess, Clayton B; Thompson, Holly M; Benedict, Stanley H; Seibert, J Anthony; Wong, Kenneth; Vaughan, Andrew T; Chen, Allen M

    2016-04-01

    Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning--a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of "gentle IGRT

  6. Clinico-morphological characteristics of reparation of acute radiation ulcer

    The mechanism of reparative processes under the effect of various drugs was studied in experimental acute radiation ulcer of rats. It was established that at the stage of marked exudative-necrotic processes the use of antiinflammatory and antiexudative substances (bariz, dimethylsulfoxyde) led to normalization of the microcirculation that reduced the time of radiation ulcer healing. The use of anabolic steroids (retabolil) intensified metabolism that also produced a favourable effect on the reparative processes

  7. Cancer risk of patients discharged with acute myocardial infarct

    Dreyer, L; Olsen, J H

    1998-01-01

    We studied whether common shared environmental or behavioral risk factors, other than tobacco smoking, underlie both atherosclerotic diseases and cancer. We identified a group of 96,891 one-year survivors of acute myocardial infarct through the Danish Hospital Discharge Register between 1977 and...... acute myocardial infarct patients were similar to those of the general population, as were the rates for hormone-related cancers, including endometrial and postmenopausal breast cancers. We found a moderate increase in the risk for tobacco-related cancers, which was strongest for patients with early...... onset of acute myocardial infarct and for female patients. Overall, there do not seem to be major shared environmental or behavioral risk factors for acute myocardial infarct and cancers, except for smoking, and there seems to be no common inherited susceptibility to the development of these diseases....

  8. Risk analysis of external radiation therapy

    External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

  9. Acute radiation syndrones and their management

    Radiation syndromes produced by large doses of ionizing radiation are divided into three general groups depending on dose of radiation and time after exposure. The CNS syndrome requires many thousands of rad, appears in minutes to hours, and kills within hours to days. The GIS appears after doses of a few hundred to 2000 rad. It is characterized by nausea, vomiting, diarrhea, and disturbances of water and electrolyte metabolism. It has a high mortality in the first week after exposure. Survivors will then experience the HS as a result of marrow aplasia. Depending on dose, survival is possible with antibiotic and transfusion therapy. The relationship of granulocyte depression to mortality in dogs and human beings is illustrated. The role of depth dose pattern of mortality of radiation exposure is described and used as an indication of why air exposure doses may be misleading. The therapy of radiation injury is described based on antibiotics, transfusion therapy, and use of molecular regulators. The limited role of matched allogenic bone marrow transplants is discussed. 52 refs., 13 figs

  10. Acute radiation syndrones and their management

    Cronkite, E.P.

    1988-01-01

    Radiation syndromes produced by large doses of ionizing radiation are divided into three general groups depending on dose of radiation and time after exposure. The CNS syndrome requires many thousands of rad, appears in minutes to hours, and kills within hours to days. The GIS appears after doses of a few hundred to 2000 rad. It is characterized by nausea, vomiting, diarrhea, and disturbances of water and electrolyte metabolism. It has a high mortality in the first week after exposure. Survivors will then experience the HS as a result of marrow aplasia. Depending on dose, survival is possible with antibiotic and transfusion therapy. The relationship of granulocyte depression to mortality in dogs and human beings is illustrated. The role of depth dose pattern of mortality of radiation exposure is described and used as an indication of why air exposure doses may be misleading. The therapy of radiation injury is described based on antibiotics, transfusion therapy, and use of molecular regulators. The limited role of matched allogenic bone marrow transplants is discussed. 52 refs., 13 figs.

  11. Developing diagnostic guidelines for the acute radiation syndrome

    Diagnostic guidelines seem to be promising for improving medical care. One aspect of a diagnostic guideline for the acute radiation syndrome has been tested against an extensive case history database. Subsequently, the guideline has been optimized for a small set of case histories. The improved performance has been proven by a test against the rest of the case history database

  12. [Epidemiological data and radiation risk estimates].

    Cardis, E

    2002-01-01

    The results of several major epidemiology studies on populations with particular exposure to ionizing radiation should become available during the first years of the 21(st) century. These studies are expected to provide answers to a number of questions concerning public health and radiation protection. Most of the populations concerned were accidentally exposed to radiation in ex-USSR or elsewhere or in a nuclear industrial context. The results will complete and test information on risk coming from studies among survivors of the Hiroshima and Nagasaki atomic bombs, particularly studies on the effects of low dose exposure and prolonged low-dose exposure, of different types of radiation, and environmental and host-related factors which could modify the risk of radiation-induced effects. These studies are thus important to assess the currently accepted scientific evidence on radiation protection for workers and the general population. In addition, supplementary information on radiation protection could be provided by formal comparisons and analyses combining data from populations with different types of exposure. Finally, in order to provide pertinent information for public health and radiation protection, future epidemiology studies should be targeted and designed to answer specific questions, concerning, for example, the risk for specific populations (children, patients, people with genetic predisposition). An integrated approach, combining epidemiology and studies on the mechanisms of radiation induction should provide particularly pertinent information. PMID:11938114

  13. Epidemiological data and radiation risk estimates

    The results of several major epidemiology studies on populations with particular exposure to ionizing radiation should become available during the first years of the 21. century. These studies are expected to provide answers to a number of questions concerning public health and radiation protection. Most of the populations concerned were accidentally exposed to radiation in ex-USSR or elsewhere or in a nuclear industrial context. The results will complete and test information on risk coming from studies among survivors of the Hiroshima and Nagasaki atomic bombs, particularly studies on the effects of low dose exposure and prolonged low-dose exposure, of different types of radiation, and environmental and host-related factors which could modify the risk of radiation-induced effects. These studies are thus important to assess the currently accepted scientific evidence on radiation protection for workers and the general population. In addition, supplementary information on radiation protection could be provided by formal comparisons and analyses combining data from populations with different types of exposure. Finally, in order to provide pertinent information for public health and radiation protection, future epidemiology studies should be targeted and designed to answer specific questions, concerning, for example, the risk for specific populations (children, patients, people with genetic predisposition). An integrated approach, combining epidemiology and studies on the mechanisms of radiation induction should provide particularly pertinent information. (author)

  14. Psychological Aspects of Acute Radiation Accidents

    This paper generally describes personality structure and needs and then relates these to the psychological aspects of radiation injury. Three levels in the personality structure are defined as child, adult, and parent. This is followed by a description of two major need systems the first of which, if not met, results in the death of the individual and the second, if not met, results in significant emotional disruption of the individual. This is followed by a discussion of coping phases and stress patterns of radiation injury, including the effects of the illusion of immunity characterized by the feeling that ''things can happen to others, but not to me'', and the ''nuclear mystique'' which is characterized by a magical quality attached to radiation due partly to the lack of sense organ response to radiation exposure. Following impact, treatment in the reactive.phase, which includes moderate and severe emotional reactions, involves a series of compensating emotions. These include the illusion of centrality, the feeling of abandonment, altruism, and amorality. The ''aftermath'' reaction is treated from the standpoint of the ''tormenting memory'', the ''amnesiac reaction'', the ''fear of recurrence'' and the individual’s need to cope with both his medical condition and reactions of others to his condition. The recovery phase is treated from the standpoint of unacceptable and acceptable disability. Finally, a recommended psychological treatment for the physician to use in radiation accident cases is made involving the individual's psychological needs, as well as the physician's psychological role which includes: authoritative support, acceptance, optimism, and avoidance of the appearance of an overly scientific approach. Effective organizing, planning or training for the care of radiation accident cases must consider the psychological factors developed. Recommendations for mental health programs which include employee screening and counselling programs are made

  15. Quantitative risk in radiation protection standards

    The bases for developing quantitative assessment of exposure risks in the human being, and the several problems that accompany the assessment and introduction of the risk of exposure to high and low LET radiation into radiation protection, will be evaluated. The extension of the pioneering radiation protection philosophies to the control of other hazardous agents that cannot be eliminated from the environment will be discussed, as will the serious misunderstandings and misuse of concepts and facts that have inevitably surrounded the application to one agent alone, of the protection philosophy that must in time be applied to a broad spectrum of potentially hazardous agents. (orig.)

  16. Radiation as a source of risk

    Essence and nature of ionizing radiation as a source of risk are reviewed. Following to the appeal of necessity and importance of campaign for enlightening risk management, of individual and of society, background knowledge and information helpful to the promotion and discussion are summarized, also. (author)

  17. Risks associated with radiation: General information

    Employers have a general responsibility to explain occupational risks to their workers. This document has been prepared to assist employers in this task. Employers should inform their workers about radiation risks associated with their work by: identifying the source(s) of radiation exposure; identifying the risk of health effects due to exposure to these sources, including the risk to the embryo and foetus of pregnant female workers; explaining the relationship between regulatory dose limits and the risk of health effects; and, explaining a worker's personal dose in terms of risk. This publication provides basic information on these subjects in a form that is clear and easy to understand. For further information, a list of suggested additional reading is included at the end of the text. (author). 15 refs., 5 tabs., 3 figs

  18. Radiation exposure and radiation risk of the population

    The major scientifically founded results concerning the assessment of the radiation exposure and the analysis and evaluation of the radiationhazards for the population, particularly in the range of low doses, are presented. As to the risk analysis special attention is paid to the rays with low ionization density (X-, γ-, β- and electronrays). Contents: 1) Detailed survey of the results and conclusions; 2) Data on the radiation load of the population; 3) Results to epidemiological questioning on the risk of cancer; 4) Genetical radiation hazards of the population. For quantification purposes of the risk of cancer by γ-radiation the observations with the a-bomb survivors in Japan are taken as a basis, as the available dosimetrical data have to be revised. Appendices: 1) German translation of the UNSCEAR-Report (1977); 2) BEIR-Report (1980); 3) Comments from the SSK on the comparability of the risks of natural-artificial radiation exposure; 4) Comments from the SSK on the importance of synergistical influences for the radiation protection (23.9.1977). (HP)

  19. Radiation risks in the workplace in perspective

    This paper puts occupational radiation risk into perspective with other risks encountered in the workplace and in society. The annual risk of fatal cancer associated with the average level of occupational exposure and the dose limit is compared with the annual risk of fatal occupational injury in other industrial sectors and with some annual risk of death from daily life. Finally, the lifetime risk associated with an exposure at the dose limit is set against the lifetime risk associated with exposure to dose limits of some chemical substances. The paper shows that the average level of radiation risk in the workplace is in the same order of magnitude as other risks for workers and follows the general trend in the reduction of risk at work observable in all sectors of the economy over the last three decades. The comparison also points out that at upper levels of individual doses, particularly when close to the dose limit, the level of risk deviates significantly from the main trends as far as risk estimates for other industrial activities are concerned. This calls for the need to pursue efforts in the implementation of the 'as low as reasonably achievable' principle in all domains. (author)

  20. Exposed persons at the Chernobyl Atomic Power Station accident: acute radiation effects

    Observation made over 115 patients with acute radiation sickness due to exposure external γ- and β-rays confirmed high efficiency of the earlier proposed principles of prognostication of the degree of severity by clinical manifestations of the primary disease response and those of separate syndromes, using the methods of hematological and cytogenetic analyses. Out of 115 victims, 56 persons had radiation burns (RB), 17 intestinal syndrome (IS), 80 - oropharengeal syndrome (ORS), 7 - interstitial radiation pneumonitis (IRP). In thanatogenesis, of prime importance were: RB (more than 40% of the body surface) - 19 persons and IRP - 7 persons. A severe course of intestinal and oropharengeal syndromes was combined with other fatal manifestations of radiation injury. Early isolation of patients (2-4 stages), selective decontamination of the intestine, prescription of a wide spectrum antibiotics, antimycotic and antiviral drugs, as well as γ-globulin could practically remove the risk of the development of fatal infectious complications during a medullary andtransitory forms of radiation sickness

  1. Relating space radiation environments to risk estimates

    Curtis, Stanley B.

    1993-01-01

    A number of considerations must go into the process of determining the risk of deleterious effects of space radiation to travelers. Among them are (1) determination of the components of the radiation environment (particle species, fluxes and energy spectra) which will encounter, (2) determination of the effects of shielding provided by the spacecraft and the bodies of the travelers which modify the incident particle spectra and mix of particles, and (3) determination of relevant biological effects of the radiation in the organs of interest. The latter can then lead to an estimation of risk from a given space scenario. Clearly, the process spans many scientific disciplines from solar and cosmic ray physics to radiation transport theeory to the multistage problem of the induction by radiation of initial lesions in living material and their evolution via physical, chemical, and biological processes at the molecular, cellular, and tissue levels to produce the end point of importance.

  2. Ionizing radiations. Prevention and risk management

    This document proposes a global approach which can be applied to any occupational situation which may result in an exposure to ionizing radiations. It aims at the development of aspects related to prevention. After having recalled the effects of ionizing radiations, a first part describes the general prevention principles as they are defined in the French labour code, the radiation protection principles as they are defined by the CIPR, and addresses risk management. The second part describes how to identify the hazard and characterize hazardous situations, and how to assess the risk and implement prevention measures. Sheets describe the assessment of external exposure, the assessment of the contamination risk by ingestion or inhalation, and the assessment of a risk of contamination by contact

  3. Radiation risks for patient and personnel

    The maximum somatic risk to be expected for the patient - in dependency of the examination method - is of the 5th-6th order; however, for radioactive iodine patients the risk of spontaneous cancer of the thyroid is expected to be three times as high. The upper limit of the genetic risk is of the 4th order; on the average, a genetic risk of the 6th-7th order is to be expected. With regard to radiation risks to persons occupied in nuclear medicine, the following can be said: The somatic X-ray cancer risk (including leukaemia) to be expected, with about 2 * 10-2%, is small compared to the spontaneous cancer risk of about 20% at present. The genetic risk for the direct descendants of persons occupationally exposed to radiation, with a maximum of 1 mutation induced by radiation in 1,000 live births, is small compared to a spontaneous risk of 1 in 100. (orig./HP)

  4. Diagnosis of acute radiation disease by Enzyme Immune-Assay (EIA)

    Diagnosis of the acute radiation disease by the method of immune enzyme assay is a simple and efficient tool of evaluating and biological dosimetry and forecasting of development of the acute radiation defeats as at group of population so at individuals locating in the zone polluted by the radiation. We use as biological markers the group of essential radiotoxins - high molecular mass glycoprotein ( molecular mass - 200 - 250 kDa ) - radiation antigens (S.D.R. - specific radiation determinant ) accumulated in the lymphoid system, with epitopes specific to each form of radiation syndrome, after animals have been irradiated in doses inducing the development of the cerebral (1), toxic ( 2), gastrointestinal ( 3 ) and typical ( 4 ) forms of acute radiation sickness. These two phenomena allowed us to develop a technologies for diagnosis, prophylaxis and therapy of radiation disease - enzyme immune assay ( EIA ), anti radiation vaccine, anti radiation serum, method of immune - lymph - plasma-sorption. The important first step in effectiveness of therapy is an accurate assessment of severity of disease in early period after irradiation. The ideal markers for early and accurate assessment is high weight glycoprotein with specifics radiation induced features (S.D.R.) mentioned above. This biology active substance isolated from lymph can induct the symptoms of radiation syndrome without previously radiation when it is administrated intra-muscularly or intravenously to healthy animals. Enzyme immune assay (EIA) allowed researchers to indicate the significant levels of different forms of S.D.R. in peripheral blood of animals in first 24 hours after radiation. Indication of high level of S.D.R. -1 allowed to forecast a fast development of cerebral form of acute radiation disease. Determination of high levels of S.D.R.-2, S.D.R.-3 and S.D.R.-4 in peripheral blood allowed to recognize early periods of toxic, gastrointestinal and typical forms of acute radiation sickness

  5. Radiation protection and risk assessment

    In its publications 22 and 26, ICRP recommends a method of optimization that requires that first the risks of the considered activity be quantitatively assessed. This paper deals with the transportation of radioactive material. Several aspects are examined: assessing risk quantitatively (as an expected number of health effects), determining the most cost-effective alternative options and applying the method to a practical example. Two of the possible applications of the results are presented in the case of transportation of UF6 in France: 1) the cost-effectiveness analysis of a set of alternative protection measures and 2) the comparison between such measures affecting risks in nuclear transportation and other measures dealing with different steps of the whole uranium fuel cycle. (HK)

  6. Risks and management of radiation exposure.

    Yamamoto, Loren G

    2013-09-01

    High-energy ionizing radiation is harmful. Low-level exposure sources include background, occupational, and medical diagnostics. Radiation disaster incidents include radioactive substance accidents and nuclear power plant accidents. Terrorism and international conflict could trigger intentional radiation disasters that include radiation dispersion devices (RDD) (a radioactive dirty bomb), deliberate exposure to industrial radioactive substances, nuclear power plant sabotage, and nuclear weapon detonation. Nuclear fissioning events such as nuclear power plant incidents and nuclear weapon detonation release radioactive fallout that include radioactive iodine 131, cesium 137, strontium 90, uranium, plutonium, and many other radioactive isotopes. An RDD dirty bomb is likely to spread only one radioactive substance, with the most likely substance being cesium 137. Cobalt 60 and strontium 90 are other RDD dirty bomb possibilities. In a radiation disaster, stable patients should be decontaminated to minimize further radiation exposure. Potassium iodide (KI) is useful for iodine 131 exposure. Prussian blue (ferric hexacyanoferrate) enhances the fecal excretion of cesium via ion exchange. Ca-DTPA (diethylenetriaminepentaacetic acid) and Zn-DTPA form stable ionic complexes with plutonium, americium, and curium, which are excreted in the urine. Amifostine enhances chemical and enzymatic repair of damaged DNA. Acute radiation sickness ranges in severity from mild to lethal, which can be assessed by the nausea/vomiting onset/duration, complete blood cell count findings, and neurologic symptoms. PMID:24201986

  7. Radiation risks : the ethics of health protection

    Since the inception of commercial uses of nuclear technology, radiation protection standards established by regulatory agencies have reflected moral concerns based on two assumptions: (1) that the linear, zero-threshold hypothesis derives from scientific data in radiobiology which are virtually conclusive; (2) it is morally better for public health protection to assume that any radiation exposure, no matter how small, has some harmful effect which can and ought to be prevented. In the past few years these beliefs and related assumptions have received closer scrutiny, revealing hidden reasons for regulatory selection of radiation risks as objects of paramount ethical concern, with the result that greater risks to health have escaped comparison and mitigation. Based on this scrutiny this brief paper explores two questions: Are presupposed assumptions ethically justified on grounds of scientific evidence and ethical consistency? and should moral objections claiming to invalidate comparative risk assessments be accepted or rejected?

  8. Aircrew radiation exposure: sources-risks-measurement

    A short review is given on the actual aircrew exposure and its sources. The resulting risks for harmful effects to the health and discuss methods for in-flight measurements of exposure is evaluated. An idea for a fairly simple and economic approach to a practical, airborne active dosimeter for the assessment of individual crew exposure is presented. The exposure of civil aircrew to cosmic radiation, should not be considered a tremendous risk to the health, there is no reason for panic. However, being significantly higher than the average exposure to radiation workers, it can certainly not be neglected. As recommended by ICRP, aircrew exposure has to be considered occupational radiation exposure and aircrews are certainly entitled to the same degree of protection, as other ground-based radiation workers have obtained by law, since long time. (author)

  9. Radiation and risk in physics education

    The study reported in this thesis deals with physics education, particularly with the teaching and learning of radioactivity and ionizing radiation. It is a follow up of earlier research and development work in the Dutch Physics Curriculum Development Project (PLON) on a unit called Ionizing Radiation. The central theme of this unit was the acceptability of the risks of ionizing radiation. Preliminary evaluation of the effectiveness of the PLON-unit showed that pupils appear to have lay-ideas which seem to be resistant to change. In this study the nature and persistence of these lay-ideas have been explored and a set of recommendations have been developed for writing curriculum materials and for teaching strategies, for physics lessons in secondary high school, in order to promote thoughtful risk analysis and assessment as regards applications of ionizing radiation. (H.W.). 225 refs.; 3 figs.; 41 tabs

  10. Ionizing Radiation Environments and Exposure Risks

    Kim, M. H. Y.

    2015-12-01

    Space radiation environments for historically large solar particle events (SPE) and galactic cosmic rays (GCR) are simulated to characterize exposures to radio-sensitive organs for missions to low-Earth orbit (LEO), moon, near-Earth asteroid, and Mars. Primary and secondary particles for SPE and GCR are transported through the respective atmospheres of Earth or Mars, space vehicle, and astronaut's body tissues using NASA's HZETRN/QMSFRG computer code. Space radiation protection methods, which are derived largely from ground-based methods recommended by the National Council on Radiation Protection and Measurements (NCRP) or International Commission on Radiological Protections (ICRP), are built on the principles of risk justification, limitation, and ALARA (as low as reasonably achievable). However, because of the large uncertainties in high charge and energy (HZE) particle radiobiology and the small population of space crews, NASA develops distinct methods to implement a space radiation protection program. For the fatal cancer risks, which have been considered the dominant risk for GCR, the NASA Space Cancer Risk (NSCR) model has been developed from recommendations by NCRP; and undergone external review by the National Research Council (NRC), NCRP, and through peer-review publications. The NSCR model uses GCR environmental models, particle transport codes describing the GCR modification by atomic and nuclear interactions in atmospheric shielding coupled with spacecraft and tissue shielding, and NASA-defined quality factors for solid cancer and leukemia risk estimates for HZE particles. By implementing the NSCR model, the exposure risks from various heliospheric conditions are assessed for the radiation environments for various-class mission types to understand architectures and strategies of human exploration missions and ultimately to contribute to the optimization of radiation safety and well-being of space crewmembers participating in long-term space missions.

  11. Evidence Report: Risk of Radiation Carcinogenesis

    Huff, Janice; Carnell, Lisa; Blattnig, Steve; Chappell, Lori; Kerry, George; Lumpkins, Sarah; Simonsen, Lisa; Slaba, Tony; Werneth, Charles

    2016-01-01

    As noted by Durante and Cucinotta (2008), cancer risk caused by exposure to space radiation is now generally considered a main hindrance to interplanetary travel for the following reasons: large uncertainties are associated with the projected cancer risk estimates; no simple and effective countermeasures are available, and significant uncertainties prevent scientists from determining the effectiveness of countermeasures. Optimizing operational parameters such as the length of space missions, crew selection for age and sex, or applying mitigation measures such as radiation shielding or use of biological countermeasures can be used to reduce risk, but these procedures have inherent limitations and are clouded by uncertainties. Space radiation is comprised of high energy protons, neutrons and high charge (Z) and energy (E) nuclei (HZE). The ionization patterns and resulting biological insults of these particles in molecules, cells, and tissues are distinct from typical terrestrial radiation, which is largely X-rays and gamma-rays, and generally characterized as low linear energy transfer (LET) radiation. Galactic cosmic rays (GCR) are comprised mostly of highly energetic protons with a small component of high charge and energy (HZE) nuclei. Prominent HZE nuclei include He, C, O, Ne, Mg, Si, and Fe. GCR ions have median energies near 1 GeV/n, and energies as high as 10 GeV/n make important contributions to the total exposure. Ionizing radiation is a well known carcinogen on Earth (BEIR 2006). The risks of cancer from X-rays and gamma-rays have been established at doses above 50 mSv (5 rem), although there are important uncertainties and on-going scientific debate about cancer risk at lower doses and at low dose rates (risks during space exploration (Cucinotta and Durante 2006; Durante and Cucinotta 2008).

  12. Radiation risk due to occupational exposure

    Exposure to ionizing radiation occurs in many occupations. Workers can be exposed to both natural and artificial sources of radiation. Any exposure to ionizing radiation incurs some risk, either to the individual or to the individual's progeny. This dissertation investigated the radiation risk due to occupational exposure in industrial radiography. Analysis of the reported risk estimates to occupational exposure contained in the UNSCEAR report of 2008 in industrial radiography practice was done. The causes of accidents in industrial radiography include: Lack of or inadequate regulatory control, inadequate training, failure to follow operational procedures, human error, equipment malfunction or defect, inadequate maintenance and wilful violation have been identified as primary causes of accidents. To minimise radiation risks in industrial radiography exposure devices and facilities should be designed such that there is intrinsic safety and operational safety ensured by establishing a quality assurance programme, safety culture fostered and maintained among all workers, industrial radiography is performed in compliance with approved local rules, workers engaged have appropriate qualifications and training, available safe operational procedures are followed, a means is provided for detecting incidents and accidents and an analysis of the causes and lessons learned. (author)

  13. Radiation risks and benefits: politics and morality

    The bioethical framework from which moral reasoning concerning nuclear technology has been derived is both seriously flawed and conceptually inadequate. The reasons are examined and are arranged in response to three questions. First, what is the status of alleged scientific evidence from which moral conclusions about the unacceptability of man-made radiation exposures are derived. Secondly, what criticisms of risk assessment reasoning are pertinent to ethical reflection. Finally, what revisions in an ethical framework are necessary if risk estimates of low-dose radiation exposure are to be conducted properly

  14. Radiation risk assessment of reprocessed uranium

    Reprocessed uranium contains 232U, which is not found in nature, as well as 234U which is present in higher proportion than in natural uranium. Both isotopes modify the radiological properties of the material. The paper evaluates the increase of the internal and external radiation risk on the base of experimental data and theoretical calculations. It also suggests measures to be taken in the production of fuel elements with slightly enriched uranium.The radiation risk of reprocessed uranium is directly proportional to the content of 232U and 234U as well as to the aging time of the material

  15. Health risks associated with environmental radiation exposures

    Much is known about health effects associated with exposure to ionising radiation. Numerous epidemiologic studies of populations exposed to radiation under a variety of circumstances have been conducted. These studies have clearly shown that radiation exposure can result in an increased risk of many types of cancer, and the findings are supported by a substantial body of literature from experimental studies. Despite the fact that radiation exposures from environmental sources comprise a relatively minor component of total population exposure, this type of exposure is often the most feared by the public. An accident like Chernobyl or a natural disaster like that at Fukushima provides a unique opportunity to learn more about the health risks from environmental radiation exposures. However, establishing the infrastructure and expertise required to design and conduct all aspects of a complex field study presents formidable challenges. This paper summarises the principal findings from the main studies of environmental radiation exposure that have been successfully undertaken. Although such studies are often exceedingly difficult to conduct, and may be limited by an ecologic design, they can be informative in assessing risk. Any new environmental study that is initiated should focus on special circumstances; additional ecological studies are not recommended. (note)

  16. Mitigating the risk of radiation-induced cancers: limitations and paradigms in drug development

    The United States radiation medical countermeasures (MCM) programme for radiological and nuclear incidents has been focusing on developing mitigators for the acute radiation syndrome (ARS) and delayed effects of acute radiation exposure (DEARE), and biodosimetry technologies to provide radiation dose assessments for guiding treatment. Because a nuclear accident or terrorist incident could potentially expose a large number of people to low to moderate doses of ionising radiation, and thus increase their excess lifetime cancer risk, there is an interest in developing mitigators for this purpose. This article discusses the current status, issues, and challenges regarding development of mitigators against radiation-induced cancers. The challenges of developing mitigators for ARS include: the long latency between exposure and cancer manifestation, limitations of animal models, potential side effects of the mitigator itself, potential need for long-term use, the complexity of human trials to demonstrate effectiveness, and statistical power constraints for measuring health risks (and reduction of health risks after mitigation) following relatively low radiation doses (<0.75 Gy). Nevertheless, progress in the understanding of the molecular mechanisms resulting in radiation injury, along with parallel progress in dose assessment technologies, make this an opportune, if not critical, time to invest in research strategies that result in the development of agents to lower the risk of radiation-induced cancers for populations that survive a significant radiation exposure incident. (review)

  17. Vascularization of bone regeneration products in acute radiation sickness

    In 119 rabbits with acute radiation sickness the vascularization process in bone regeneration products was studied by microangiography. The formation of arteries and of bone structures was retarded in irradiated animals. The deficient formation of veins and capillaries did not cause conditions for venous blood circulation and resulted in a slow resorption of newly formed bone structures and gristle. That is one of the reasons for an extended healing process of fractures and for formation of false articulations in irradiated animals. (author)

  18. Comparison of radiation and chemical risks

    Injury to living cells is caused by mechanisms which in many cases are similar for radiation and chemicals. It is thus not surprising that radiation and many chemicals can cause similar biological effects, e.g. cancer, fetal injury and hereditary disease. Both radiation and chemicals are always found in our environment. One agent may strengthen or weaken the effect of another, be it radiation in combination with chemicals or one chemical with another. The implications of such synergistic or antagonistic effects are discussed. Intricate mechanisms help the body to defend itself against threats to health from radiation and chemicals, even against cancer risks. In a strategy for health, it might be worth to exploit actively these defense mechanisms, in parallel with decreasing the exposures. On particular interest are the large exposures from commonly known sources such as smoking, sun tanning and high fat contents of food. (author)

  19. Risk of cardiovascular disease following radiation exposure

    Excess radiation-induced cardiac mortalities have been reported among radiotherapy patients. Many case reports describe the occurrence of atherosclerosis following radiotherapy for Hodgkin's disease and breast cancer. Some case reports describe the cerebral infarction following radiotherapy to neck region, and of peripheral vascular disease of the lower extremities following radiotherapy to the pelvic region. The association of atomic bomb radiation and cardiovascular disease has been examined recently by incidence studies and prevalence studies of various endpoints of atherosclerosis; all endpoints indicated an increase of cardiovascular disease in the exposed group. It is almost certain that the cardiovascular disease is higher among atomic bomb survivors. However, since a heavy exposure of 10-40 Gy is delivered in radiotherapy and the bomb survivors were exposed to radiation at high dose and dose-rate, the question is whether the results can be extrapolated to individuals exposed to lower levels of radiation. Some recent epidemiological studies on occupationally exposed workers and population living near Chernobyl have provided the evidence for cardiovascular disease being a significant late effect at relatively low doses of radiation. However, the issue of non-cancer mortality from radiation is complicated by lack of adequate information on doses, and many other confounding factors (e.g., smoking habits or socio-economic status). This presentation will evaluate possible radiobiological mechanisms for radiation-induced cardiovascular disease, and will address its relevance to radiation protection management at low doses and what the impact might be on future radiation risk assessments. (authors)

  20. Risks from radiation - perception and reality

    Although we know a great deal about the risks to health from external ionizing radiation, there may be some points where we must be prepared to modify our understanding. We must take account of the concerns of the public in relation to risks that they dread. In the complex ecological and physiological systems which constitute our world, there are infinite number of peculiar circumstances affecting the distribution of specific radionuclides, the energy our tissues receive and the susceptibility of those tissues. (author)

  1. Acute Exercise Increases Sex Differences in Amateur Athletes' Risk Taking.

    Pighin, S; Savadori, L; Bonini, N; Andreozzi, L; Savoldelli, A; Schena, F

    2015-10-01

    The research presented here investigates the interaction between acute exercise, biological sex and risk-taking behavior. The study involved 20 amateur athletes (19-33 years old), 10 males and 10 females, who were asked to undergo subsequent experimental sessions designed to compare their risky behaviors on the Balloon Analogue Risk Task (BART) 34 at rest and while exercising at moderate intensity (60% of their maximal aerobic power). Results showed that physical exercise affected male and female participants differently: Whereas males became more risk seeking, females became more risk averse during exercise. PMID:26090877

  2. Risk assessment perspectives in radiation protection

    Risk evaluation involves a) optimization, where collective dose is reduced by application of controls, b) justification, where benefits and costs are balanced, and c) application of dose limits. Justification may be determined in general by examining the difference between the new practice and a reference condition in the form of a diference equation. This equation is expanded to take into account other risks in addition to radiation risks. The relative potencies of some toxic chemicals are compared with those of some isotopes. Nuclear and waste disposal accidents are also considered. It is concluded that a probablistic analysis may be useful for resolving the high level radioactive waste question but not for nuclear accidents. However, in the latter case, relative risk models may provide insight into the causes of risk and where resources for reducing the risk may be best spent. (H.K.)

  3. Radiation Dose-Response Relationships and Risk Assessment

    The notion of a dose-response relationship was probably invented shortly after the discovery of poisons, the invention of alcoholic beverages, and the bringing of fire into a confined space in the forgotten depths of ancient prehistory. The amount of poison or medicine ingested can easily be observed to affect the behavior, health, or sickness outcome. Threshold effects, such as death, could be easily understood for intoxicants, medicine, and poisons. As Paracelsus (1493-1541), the 'father' of modern toxicology said, 'It is the dose that makes the poison.' Perhaps less obvious is the fact that implicit in such dose-response relationships is also the notion of dose rate. Usually, the dose is administered fairly acutely, in a single injection, pill, or swallow; a few puffs on a pipe; or a meal of eating or drinking. The same amount of intoxicants, medicine, or poisons administered over a week or month might have little or no observable effect. Thus, before the discovery of ionizing radiation in the late 19th century, toxicology ('the science of poisons') and pharmacology had deeply ingrained notions of dose-response relationships. This chapter demonstrates that the notion of a dose-response relationship for ionizing radiation is hopelessly simplistic from a scientific standpoint. While useful from a policy or regulatory standpoint, dose-response relationships cannot possibly convey enough information to describe the problem from a quantitative view of radiation biology, nor can they address societal values. Three sections of this chapter address the concepts, observations, and theories that contribute to the scientific input to the practice of managing risks from exposure to ionizing radiation. The presentation begins with irradiation regimes, followed by responses to high and low doses of ionizing radiation, and a discussion of how all of this can inform radiation risk management. The knowledge that is really needed for prediction of individual risk is presented

  4. Assessment of genetic risk for human exposure to radiation

    Full text: The methodology of assessing the genetic risk of radiation exposure is based on the concept of 'hitting the target' in development of which N.V. Timofeeff-Ressovsky has played and important role. To predict genetic risk posed by irradiation, the U N Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has worked out direct and indirect methods of assessment, extrapolation, integral and palpitation criteria of risk analysis that together permit calculating the risk from human exposure on the basis of data obtained for mice. Based on the reports of UNSCEAR for the period from 1958 to 2001 the paper presents a retrospective analysis of the use of direct methods and the doubling dose method for quantitative determination of the genetic risk of human exposure expressed as different hereditary diseases. As early as 1962 UNSCEAR estimated the doubling dose (a dose causing as many mutations as those occurring spontaneously during one generation) at 1 Gy for cases of exposure to ionizing radiations with low LET at a low dose rate and this value was confirmed in the next UNSCEAR reports up to now. For cases of acute irradiation the doubling dose was estimated at 0,3-0,4 Gy for the period under review. The paper considers the evolution of the concepts of human natural hereditary variability which is a basis for assessing the risk of exposure by the doubling dose method. The level of human natural genetic variability per 1 000 000 newborns is estimated at 738 000 hereditary diseases including mendelian, chromosomal and multifactorial ones. The greatest difficulties in assessing the doubling dose value were found to occur in the case of multifactorial diseases the pheno typical expression of which depends on mutational events in polygenic systems and on numerous environmental factors. The introduction in calculations of the potential recoverability correction factor (RPCF) made it possible to assess the genetic risk taking into account this class of

  5. Transfusion-related acute lung injury: incidence and risk factors

    Toy, Pearl; Gajic, Ognjen; Bacchetti, Peter; Looney, Mark R.; Gropper, Michael A.; Hubmayr, Rolf; Lowell, Clifford A.; Norris, Philip J; Murphy, Edward L; Weiskopf, Richard B.; Wilson, Gregory; Koenigsberg, Monique; Lee, Deanna; Schuller, Randy; Wu, Ping

    2012-01-01

    Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related mortality. To determine TRALI incidence by prospective, active surveillance and to identify risk factors by a case-control study, 2 academic medical centers enrolled 89 cases and 164 transfused controls. Recipient risk factors identified by multivariate analysis were higher IL-8 levels, liver surgery, chronic alcohol abuse, shock, higher peak airway pressure while being mechanically ventilated, current s...

  6. Transfusion-related acute lung injury: Incidence and risk factors

    Toy, P; Gajic, O; Bacchetti, P; Looney, MR; Gropper, MA; Hubmayr, R; Lowell, CA; Norris, PJ; Murphy, EL; Weiskopf, RB; Wilson, G; Koenigsberg, M; Lee, D.; Schuller, R.; Wu, P.

    2011-01-01

    Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion- related mortality. To determine TRALI incidence by prospective, active surveillance and to identify risk factors by a case-control study, 2 academic medical centers enrolled 89 cases and 164 transfused controls. Recipient risk factors identified by multivariate analysis were higher IL-8 levels, liver surgery, chronic alcohol abuse, shock, higher peak airway pressure while being mechanically ventilated, current ...

  7. Protective effects of gelsolin on acute radiation symptom

    This paper is to study the protective effect of gelsolin on acute radiation symptoms after total body irradiation. The concentration of plasma gelsolin was determined by a commercial ELISA Kit before and post-irradiation at different times by 137Cs γ rays with 4 Gy and 8 Gy. Levels of prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen (FIB) were detected by an STAGO blood coagulation instrument at different times post-irradiation with 6 Gy γ ray. Otherwise the contents of the plasma malonaldehyde (MDA), superoxide dismutase (SOD) and whole blood glutathione (GSH) were examined at 2 d and 7 a respectively after radiation. We found that the plasma levels of gelsolin were rising at 24 h post-radiation and a persistent degression tendency of gelsolin concentration was found from 24 h to 72 h post-irradiation with 4 Gy and 8 Gy. This decreasing degree had a positive correlation with the exposure dose. On the day from 4 d to 7 d after radiation treatment, the gelsolin treatment group had significantly higher PT and APTT, but low FIB than those of irradiated control group. Within 14 d to 18 d post-radiation, APTT, PT and FIB in gelsolin treatment group were lower than those in irradiated control group, but only APTT and PT differences were prominent. Levels of GSH and SOD in gelsolin treatment group were conspicuously higher than those in irradiated control group; whereas MDA levels were significantly lower than the irradiated control group. Gelsolin may have some certain protective effects on acute radiation disease in improving radiation hemorrhagic injury and eliminating free radicals. (authors)

  8. A two-mutation model of radiation-induced acute myeloid leukemia using historical mouse data.

    Dekkers, Fieke; Bijwaard, Harmen; Bouffler, Simon; Ellender, Michele; Huiskamp, René; Kowalczuk, Christine; Meijne, Emmy; Sutmuller, Marjolein

    2011-03-01

    From studies of the atomic bomb survivors, it is well known that ionizing radiation causes several forms of leukemia. However, since the specific mechanism behind this process remains largely unknown, it is difficult to extrapolate carcinogenic effects at acute high-dose exposures to risk estimates for the chronic low-dose exposures that are important for radiation protection purposes. Recently, it has become clear that the induction of acute myeloid leukemia (AML) in CBA/H mice takes place through two key steps, both involving the Sfpi1 gene. A similar mechanism may play a role in human radiation-induced AML. In the present paper, a two-mutation carcinogenesis model is applied to model AML in several data sets of X-ray- and neutron-exposed CBA/H mice. The models obtained provide good fits to the data. A comparison between the predictions for neutron-induced and X-ray-induced AML yields an RBE for neutrons of approximately 3. The model used is considered to be a first step toward a model for human radiation-induced AML, which could be used to estimate risks of exposure to low doses. PMID:20842369

  9. New scoring system identifies kidney outcome with radiation therapy in acute renal allograft rejection

    Purpose: To evaluate the role of radiation therapy for acute refractory renal rejection after failure of medical intervention, and to identify risk factors that influence graft survival following radiation therapy. Methods: Between June 1989 and December 1995, 53 renal transplant recipients (34 men and 19 women) were treated with localized radiation therapy for acute renal allograft rejection. Graft rejection was defined as an increase in serum creatinine with histologic evidence of rejection on renal biopsy. Ninety-one percent were cadaveric transplant recipients. The majority of patients who experienced acute graft rejection initially received corticosteroid therapy, except for 25% who were referred for radiation therapy and steroids for the first rejection. In more recent years, patients with moderate or severe steroid-resistant or recurrent rejection received OKT3, a polyclonal antilymphocyte antibody (ATGAM), tacrolimus (FK506), or mycophenolate mofetil (MMF). Patients who failed to respond to medical treatment were then referred for radiation therapy. Ultrasound was performed for kidney localization. Treatment consisted of a dose of 600 cGy given in 3 or 4 fractions using 6 MV photons, delivered AP or AP/PA. Results: The overall actuarial graft survival from the initiation of RT was 83% at 1 month, 60% at 1 year, and 36% at 5 years. The median follow-up from the date of transplant to the last follow-up was 22 months. The median time from the date of transplant to the initiation of radiotherapy was 3 months, and the median time from the initiation of radiotherapy to the last follow-up was 10 months. Variables evaluated were as follows: human leukocyte antigen matching on HLA-A, HLA-B, and HLA-DR, the transplant panel-reactive antibodies (PRA) at transplantation, number of acute rejection episodes, interval from the date of the transplant to the first rejection, serum creatinine levels at the time of the first radiation treatment, number of transplants, and

  10. Acute Radiation Disease : Cutaneous Syndrome and Toxic properties of Radiomimetics -Radiation Neurotoxins and Hematotoxins.

    Popov, Dmitri; Maliev, Slava

    Cutaneous injury is an important complication of a general or local acute irradiation. A type of a skin and tissues lesions depends on a type, intensity, and period of irradiation. Also, the clinical picture, signs, and manifestations of the cutaneous syndrome depend on a type of the radiation toxins circulated in lymph and blood of irradiated mammals. Radiation Toxins were isolated from lymph of the mammals that were irradiated and developed different forms of the Acute Radiation Syndromes (ARS) -Cerebrovascular, Cardiovascular, Gastrointestinal, and Hematopoietic. Radiation Toxins can be divided into the two important types of toxins (Neu-rotoxins and Hematotoxins) or four groups. The effects of Radiation Neurotoxins include severe damages and cell death of brain, heart, gastrointestinal tissues and endothelial cells of blood and lymphatic vessels. The hematotoxicity of Hematotoxic Radiation Toxins includes lym-phopenia, leukopenia, thrombocytopenia, and anemia in the blood circulation and transitory lymphocytosis and leukocytosis in the Central Lymphatic System. In all cases, administration of the Radiomimetics (Radiation Toxins) intramuscularly or intravenously to healthy, radiation naive mammals had induced and developed the typical clinical manifestations of the ARS. In all cases, administration of Radiomimetics by subtoxic doses had demonstrated development of typical clinical signs of the cutaneous syndrome such as hair loss, erythema, swelling, desqua-mation, blistering and skin necrosis. In animal-toxic models, we have activated development of the local skin and tissue injury after injection of Radiation Toxins with cytoxic properties.

  11. Cerebrovascular Acute Radiation Syndrome : Radiation Neurotoxins, Mechanisms of Toxicity, Neuroimmune Interactions.

    Popov, Dmitri; Maliev, Slava

    Introduction: Cerebrovascular Acute Radiation Syndrome (CvARS) is an extremely severe in-jury of Central Nervous System (CNS) and Peripheral Nervous System (PNS). CvARS can be induced by the high doses of neutron, heavy ions, or gamma radiation. The Syndrome clinical picture depends on a type, timing, and the doses of radiation. Four grades of the CvARS were defined: mild, moderate, severe, and extremely severe. Also, four stages of CvARS were developed: prodromal, latent, manifest, outcome -death. Duration of stages depends on the types, doses, and time of radiation. The CvARS clinical symptoms are: respiratory distress, hypotension, cerebral edema, severe disorder of cerebral blood microcirculation, and acute motor weakness. The radiation toxins, Cerebro-Vascular Radiation Neurotoxins (SvARSn), determine development of the acute radiation syndrome. Mechanism of action of the toxins: Though pathogenesis of radiation injury of CNS remains unknown, our concept describes the Cv ARS as a result of Neurotoxicity and Excitotoxicity, cell death through apoptotic necrosis. Neurotoxicity occurs after the high doses radiation exposure, formation of radiation neuro-toxins, possible bioradicals, or group of specific enzymes. Intracerebral hemorrhage can be a consequence of the damage of endothelial cells caused by radiation and the radiation tox-ins. Disruption of blood-brain barrier (BBB)and blood-cerebrospinal fluid barrier (BCFB)is possibly the most significant effect of microcirculation disorder and metabolic insufficiency. NMDA-receptors excitotoxic injury mediated by cerebral ischemia and cerebral hypoxia. Dam-age of the pyramidal cells in layers 3 and 5 and Purkinje cell layer the cerebral cortex , damage of pyramidal cells in the hippocampus occur as a result of cerebral ischemia and intracerebral bleeding. Methods: Radiation Toxins of CV ARS are defined as glycoproteins with the molec-ular weight of RT toxins ranges from 200-250 kDa and with high enzymatic activity

  12. Cranial radiation in childhood acute lymphocytic leukemia. Neuropsychologic sequelae

    A battery of neuropsychologic tests was administered ''blindly'' to 18 children with acute lymphocytic leukemia (ALL) who had been randomly assigned to treatment regimens with or without cranial radiation. These children were all in complete continuous remission for more than 3 1/2 years and were no longer receiving therapy. The results indicated no substantial differences between groups as a function of radiation therapy. However, decreased neuropsychologic performance was found when the entire sample was compared with population norms. These data do not support the hypothesis that cranial radiation therapy is responsible for the neuropsychologic sequelae seen in these survivors of ALL. Post hoc multiple regression analysis indicated that parental education levels accounted for more of the neuropsychologic variability seen in these children than other factors such as age at diagnosis, type of therapy, or sex of child

  13. Macrophage expression in acute radiation colitis in rats

    Although radiation therapy is important in the treatment of tumors in pelvic and abdominal region, it may cause radiation injury as a side effect. But there is no effective way of preventing or curing the damages. The mechanism of acute radiation colitis has not been elucidated yet. Our previous reports have revealed that X-ray irradiation induce apoptosis of epithelial stem cells in colon. Then a hypothesis of the radiation colitis can be put forward, DNA damage by irradiation, apoptosis of mucosal epithelial stem cells and degeneration of epithelial gland structure, macrophages phagocyte the debris, being activated and secreting various inflammatory cytokines, infiltration of inflammatory cells. Several recent reports show that macrophages may play an important role in the process of inflammatory bowel diseases such ulcerative colitis or Crohn's disease. We studied radiation colitis using rat animal models. Male Wister rats were irradiated by a single fraction dose of 22.5 Gy X-ray at laparotomy, shielding except for an approximately 2.5 cm length of rectum. Histological changes and macrophage accumulation in the rectum mucosa were evaluated by immunohistochemistry and western blot method with the specimens which were taken on the 1, 2, 3, 4, 5, 6, 7, 10, and 14th day after irradiation. Severe macrophage accumulation in the lamina propria of the rectum was observed on the 5th day. At the same time, severe destruction of mucosal structure and inflammatory cells infiltration were also observed. Based on the potent pro-inflammatory cytokine producing effects of macrophage in rat and the increased expression in inflammatory bowel disease patients, speculate that intervention in the macrophage-cytokine network could form a future target for the treatment of acute radiation colitis. (author)

  14. Methods for assessing the extent of acute radiation injury

    Previous radiation accidents have shown that the medical management of exposed persons cannot be performed without the use of 'biological indicators' of effect and of repair. For the clinical management of a patient with the acute radiation syndrome, it is essential to obtain information on the subjective symptomatology as well as on laboratory parameters, especially during the first 3 to 6 days after exposure. The medical doctor responsible for the clinical care of patients has to rely on the use of what has been described as 'sequential diagnosis'. This approach consists essentially of the determination of a limited number of parameters as a function of time. From the analysis of the pattern of the determined and evaluated signs and symptoms in the first hours and days, one is able to characterize patients according to type and severity of symptomatology. This has been clearly demonstrated in the Moscow - Ulm Radiation Accident Database (MURAD) developed in a collaborative project between the Institute of Biophysics in Moscow and the Department of Clinical Physiology and Occupational Medicine of the University of Ulm. On the basis of the radiation accident clinical response pattern observed early after irradiation, one is able to develop a first approach for therapeutic strategies. It is the purpose of this contribution to outline the diagnostic and prognostic significance of blood cell changes and to discuss the following problem areas: significance and elements of a sequential diagnosis; significance of blood lymphocytes for radiation accident diagnosis; significance of blood granulocyte changes for the prognosis of the acute radiation syndrome; analysis of granulocyte changes by means of regulated system models; utilization of indicators of response and repair for planning therapeutic options

  15. Radiation induced cancer risk, detriment and radiation protection

    Recommendations on radiation protection limits for workers and for the public depend mainly on the total health detriment estimated to be the result of low dose ionizing radiation exposure. This detriment includes the probability of a fatal cancer, an allowance for the morbidity due to non-fatal cancer and the probability of severe hereditary effects in succeeding generations. In a population of all ages, special effects on the fetus particularly the risk of mental retardation at defined gestational ages, should also be included. Among these components of detriment after low doses, the risk of fatal cancer is the largest and most important. The estimates of fatal cancer risk used by ICRP in the 1990 recommendations were derived almost exclusively from the study of the Japanese survivors of the atomic bombs of 1945. How good are these estimates? Uncertainties associated with them, apart from those due to limitations in epidemiological observation and dosimetry, are principally those due to projection forward in time and extrapolation from high dose and dose rate to low dose and dose rate, each of which could after the estimate by a factor of 2 or so. Recent estimates of risk of cancer derived directly from low dose studies are specific only within very broad ranges of risk. Nevertheless, such studies are important as confirmation or otherwise of the estimates derived from the atomic bomb survivors. Recent U.S. British and Russian studies are examined in this light. (author)

  16. Risk of stroke after acute myocardial infarction among Chinese

    2001-01-01

    @@Following an acute myocardial infarction (AMI), patients have an increased risk of stroke. Estimates of risk are mainly derived from AMI treatment trials or secondary prevention studies. The reported incidence of stroke in Caucasians in the early phase after AMI ranged from 0.5% to 2.5%.1-3 Similar assessment of risk in the Chinese population is lacking. As thrombolytic therapy becomes standard treatment for AMI, there is concern that there may be an increase in haemorrhagic stroke complicating AMI treatment, especially since haemorrhagic stroke is more common in Asian populations.

  17. Radiation and society: Comprehending radiation risk. V. 2. Poster papers. Proceedings of an international conference

    This IAEA international conference on Radiation and Society was the first major international meeting devoted to the comprehension of radiation risk, public attitude towards radiation risk and hazards encountered by the general public in contaminated areas. Volume two of the proceedings mainly deals with assessment of radiation exposure levels, radiation health effects, impact of radiation on the environment, perception of and managing radiation risk. Refs, figs, tabs

  18. Acute syndrome of radiation: injuries to the gastrointestinal tract

    Acute syndrome of radiation: injuries to the gastrointestinal tract. Exposure to ionising radiation at medium to high doses results in the manifestation of mixed pathologies. Following the analysis of several radiation accidents it is clear that intestinal injury influences patient survival. However the appearance of the classically defined gastrointestinal syndrome is not always evident. Nevertheless injury to the gastrointestinal tract, in particular loss of barrier function, seems to play an important role in the development of Multiple Organ Failure such as reported in the recent accident at Tokai Mura. Ionising radiation overexposure results in changes in intestinal motility and nutrient, fluid and electrolyte absorption and secretion all which may contribute to the genesis of diarrhea. In addition to modified cellular transport properties for nutrients or electrolytes, important loss of epithelial cells is also a major contributing factor. Intestinal functions are controlled by many factors such as neurotransmitters, locally released mediators from endocrine cells or immunocompetent cells in addition to luminal agents. To date, treatment of radiation-induced gastrointestinal injury is mainly symptomatic. However treatments such as growth factors, anti-inflammatory cytokines as well as cellular transplantation remain to be validated in the radiation accident situation. (author)

  19. Toxicity risk of non-target organs at risk receiving low-dose radiation: case report

    The spine is the most common site for bone metastases. Radiation therapy is a common treatment for palliation of pain and for prevention or treatment of spinal cord compression. Helical tomotherapy (HT), a new image-guided intensity modulated radiotherapy (IMRT), delivers highly conformal dose distributions and provides an impressive ability to spare adjacent organs at risk, thus increasing the local control of spinal column metastases and decreasing the potential risk of critical organs under treatment. However, there are a lot of non-target organs at risk (OARs) occupied by low dose with underestimate in this modern rotational IMRT treatment. Herein, we report a case of a pathologic compression fracture of the T9 vertebra in a 55-year-old patient with cholangiocarcinoma. The patient underwent HT at a dose of 30 Gy/10 fractions delivered to T8-T10 for symptom relief. Two weeks after the radiotherapy had been completed, the first course of chemotherapy comprising gemcitabine, fluorouracil, and leucovorin was administered. After two weeks of chemotherapy, however, the patient developed progressive dyspnea. A computed tomography scan of the chest revealed an interstitial pattern with traction bronchiectasis, diffuse ground-glass opacities, and cystic change with fibrosis. Acute radiation pneumonitis was diagnosed. Oncologists should be alert to the potential risk of radiation toxicities caused by low dose off-targets and abscopal effects even with highly conformal radiotherapy

  20. Hematopoietic Acute Radiation Syndrome (Bone marrow syndrome, Aplastic Anemia): Molecular Mechanisms of Radiation Toxicity.

    Popov, Dmitri

    Key Words: Aplastic Anemia (AA), Pluripotential Stem Cells (PSC) Introduction: Aplastic Anemia (AA) is a disorder of the pluripotential stem cells involve a decrease in the number of cells of myeloid, erythroid and megakaryotic lineage [Segel et al. 2000 ]. The etiology of AA include idiopathic cases and secondary aplastic anemia after exposure to drugs, toxins, chemicals, viral infections, lympho-proliferative diseases, radiation, genetic causes, myelodisplastic syndromes and hypoplastic anemias, thymomas, lymphomas. [Brodskyet al. 2005.,Modan et al. 1975., Szklo et al. 1975]. Hematopoietic Acute Radiation Syndrome (or Bone marrow syndrome, or Radiation-Acquired Aplastic Anemia) is the acute toxic syndrome which usually occurs with a dose of irradiation between 0.7 and 10 Gy (70- 1000 rads), depending on the species irradiated. [Waselenko et al., 2004]. The etiology of bone morrow damage from high-level radiation exposure results depends on the radiosensitivity of certain bone marrow cell lines. [Waselenko et al. 2004] Aplastic anemia after radiation exposure is a clinical syndrome that results from a marked disorder of bone marrow blood cell production. [Waselenko et al. 2004] Radiation hematotoxicity is mediated via genotoxic and other specific toxic mechanisms, leading to aplasia, cell apoptosis or necrosis, initiation via genetic mechanisms of clonal disorders, in cases such as the acute radiation-acquired form of AA. AA results from radiation injury to pluripotential and multipotential stem cells in the bone marrow. The clinical signs displayed in reticulocytopenia, anemia, granulocytopenia, monocytopenia, and thrombocytopenia. The number of marrow CD34+ cells (multipotential hematopoietic progenitors) and their derivative colony-forming unit{granulocyte-macrophage (CFU-GM) and burst forming unit {erythroid (BFU{E) are reduced markedly in patients with AA. [Guinan 2011, Brodski et al. 2005, Beutler et al.,2000] Cells expressing CD34 (CD34+ cell) are normally

  1. Environmental radiation standards and risk limitation

    The Environmental Protection Agency and Nuclear Regulatory Commission have established environmental radiation standards for specific practices which correspond to limits on risk to the public that vary by several orders of magnitude and often are much less than radiation risks that are essentially unregulated, e.g., risks from radon in homes. This paper discusses a proposed framework for environmental radiation standards that would improve the correspondence with limitation of risk. This framework includes the use of limits on annual effective dose equivalent averaged over a lifetime, rather than limits on dose equivalent to whole body or any organ for each year of exposure, and consideration of exposures of younger age groups as well as adults; limits on annual effective dose equivalent averaged over a lifetime no lower than 0.25 mSv (25 mrem) per practice; maintenance of all exposures as low as reasonably achievable (ALARA); and establishment of a generally applicable de minimis dose for public exposures. Implications of the proposed regulatory framework for the current system of standards for limiting public exposures are discussed. 20 refs

  2. The 15-Country Collaborative Study of Cancer Risk Among Radiation Workers in the Nuclear Industry

    Vrijheid, M; Cardis, E; Blettner, M;

    2007-01-01

    Radiation protection standards are based mainly on risk estimates from studies of atomic bomb survivors in Japan. The validity of extrapolations from the relatively high-dose acute exposures in this population to the low-dose, protracted or fractionated environmental and occupational exposures...

  3. Acute phase response before treatment predicts radiation esophagitis in non-small cell lung cancer

    Background and purpose: Radiation esophagitis (RE) represents an inflammatory reaction to radiation therapy (RT). We hypothesized that aspects of the physiologic acute phase response (APR) predicts RE. Material and methods: We retrospectively analyzed 285 patients with non-small cell lung cancer (NSCLC) treated with definitive radiation. The primary analysis was the association of pretreatment lab values reflective of the APR with symptomatic (grade ⩾2) RE. Univariate and multivariate odds ratios (ORs) were calculated to test associations of clinical and pretreatment lab values with RE. Optimal cutpoints and multivariable risk stratification groupings were determined via recursive partitioning analysis. Results: Pretreatment platelet counts were higher and hemoglobin levels lower in patients who developed RE (P < 0.05). Based on these two pre-treatment risk factors, an APR score was defined as 0 (no risk factors), 1 (either risk factor), or 2 (both risk factors). APR score was significantly associated with RE in both univariate (OR = 2.3 for each point, 95% confidence interval [CI] 1.5–3.4, P = 0.001) and multivariate (OR = 2.1, 95% CI 1.3–3.4, P = 0.002) analyses. Conclusions: The APR score may represent a novel metric to predict RE. However, pending validation in an independent dataset, caution is advised when interpreting these results given their retrospective and thus exploratory nature

  4. STUDY OF RISK FACTORS AND CLINICAL PROFILE OF ACUTE STROKE

    Tomar

    2014-05-01

    Full Text Available `INTRODUCTION: Stroke is the third leading cause of death in developed countries after cardiovascular disease and cancer. In India Community Surveys have shown a crude prevalence rate for hemiplegia 200 per 1, 00, 000 population. It accounts for nearly 1.5% of all urban admissions, 4.5 % of all medical and about 20% of neurological cases. AIMS AND OBJECTIVE: Identification of risk factors and evaluation of clinical profile of acute stroke. MATERIAL AND METHOD: INCLUSION CRITERIA: Cases of acute stoke admitted in SGMH hospital were selected for the study. EXCLUSION CRITERIA: Brain injury cases, infective, neoplastic cases producing stroke were excluded. RESULTS: Stroke was more common in male, 58 % patients were male and 42% patients were female. It was more common in 5th and 6th decade. Most common etiology was infarction. Most common risk factor was hypertension followed by smoking. In addition to limb weakness, headache and vomiting were most common presenting symptoms followed by convulsion. These symptoms were more common in hemorrhagic stroke. Right sided hemiplegia was more common than left sided. Middle cerebral artery was involved in majority of cases in atherothrombotic stroke whereas basal ganglion was most common site of bleed in hemorrhagic stroke. Coma and mortality were more in hemorrhagic stroke. CONCLUSION: The risk factors and clinical profile of acute stroke in India are similar to that of Western countries. Common risk factors are hypertension, smoking, diabetes mellitus and hyperlipidemia

  5. The analysis of prognostic factors affecting post-radiation acute reaction after conformal radiotherapy for non-small cell lung cancer

    Spych, Michał; Gottwald, Leszek; Klonowicz, Małgorzata; Biegała, Michał; Bibik, Robert; Fijuth, Jacek

    2010-01-01

    Introduction The aim was to evaluate the risk of acute side effects in the lung after 3-dimensional conformal radiotherapy (3D-CRT) in patients treated for non-small cell lung cancer (NSCLC). An attempt was made to single out clinical factors and factors related to treatment technique which may induce acute post-radiation pneumonitis. Material and methods The analysis concerned 34 consecutive patients who underwent radical radiation therapy for NSCLC. Intensity of early toxicity was evaluated...

  6. Potential for a pluripotent adult stem cell treatment for acute radiation sickness

    Rodgerson, Denis O.; Reidenberg, Bruce E; Harris, Alan G; Pecora, Andrew L.

    2012-01-01

    Accidental radiation exposure and the threat of deliberate radiation exposure have been in the news and are a public health concern. Experience with acute radiation sickness has been gathered from atomic blast survivors of Hiroshima and Nagasaki and from civilian nuclear accidents as well as experience gained during the development of radiation therapy for cancer. This paper reviews the medical treatment reports relevant to acute radiation sickness among the survivors of atomic weapons at Hir...

  7. Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

    Chapet, Olivier, E-mail: olivier.chapet@chu-lyon.fr [Department of Radiation Oncology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); EMR3738, Université Lyon 1, Lyon (France); Decullier, Evelyne; Bin, Sylvie [Pole Information Médicale Evaluation Recherche, Hospices Civils de Lyon, Lyon (France); Université Lyon 1, Lyon (France); EA SIS, Université de Lyon, Lyon (France); Faix, Antoine [Department of Urology, Clinique Beausoleil, Montpellier (France); Ruffion, Alain [Université Lyon 1, Lyon (France); Department of Urology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Jalade, Patrice [Department of Medical Physics, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Fenoglietto, Pascal [Department of Radiation Oncology and Physics, Institut du Cancer de Montpellier, Montpellier (France); Udrescu, Corina; Enachescu, Ciprian [Department of Radiation Oncology, Hospices Civils de Lyon, Centre Hospitalier Lyon Sud, Pierre Benite (France); Azria, David [Department of Radiation Oncology and Physics, Institut du Cancer de Montpellier, Montpellier (France)

    2015-03-15

    Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity.

  8. Prostate Hypofractionated Radiation Therapy With Injection of Hyaluronic Acid: Acute Toxicities in a Phase 2 Study

    Purpose: Hypofractionated radiation therapy (RT) in prostate cancer can be developed only if the risk of rectal toxicity is controlled. In a multicenter phase 2 trial, hypofractionated irradiation was combined with an injection of hyaluronic acid (HA) to preserve the rectal wall. Tolerance of the injection and acute toxicity rates are reported. Methods and Materials: The study was designed to assess late grade 2 toxicity rates. The results described here correspond to the secondary objectives. Acute toxicity was defined as occurring during RT or within 3 months after RT and graded according to the Common Terminology Criteria for Adverse Events version 4.0. HA tolerance was evaluated with a visual analog scale during the injection and 30 minutes after injection and then by use of the Common Terminology Criteria at each visit. Results: From 2010 to 2012, 36 patients with low-risk to intermediate-risk prostate cancer were included. The HA injection induced a mean pain score of 4.6/10 ± 2.3. Thirty minutes after the injection, 2 patients still reported pain (2/10 and 3/10), which persisted after the intervention. Thirty-three patients experienced at least 1 acute genitourinary toxicity and 20 patients at least 1 acute gastrointestinal toxicity. Grade 2 toxicities were reported for 19 patients with urinary obstruction, frequency, or both and for 1 patient with proctitis. No grade 3 or 4 toxicities were reported. At the 3-month visit, 4 patients described grade 2 obstruction or frequency, and no patients had any grade 2 gastrointestinal toxicities. Conclusions: The injection of HA makes it possible to deliver hypofractionated irradiation over 4 weeks with a dose per fraction of > 3 Gy, with limited acute rectal toxicity

  9. Quantitative assessment of acute radiation injury of the lens

    An attempt is made to unify various approaches to the assessment of acute radiation injury of the organ of vision. The development of cataracts was studied on mice subjected to local irradiation of the head at doses: 7, 10, 12, 15, 20 and 25 Gy. A clinical picture of radiation injury of the eye at different X-ray doses at different stages was established during ophthalmological examination using a manual electroophthalmoscope (X5). A method of the quantitative assessment of radiation injury of the mouse eye at different radiation doses was proposed using the light transmission factor tau; its experimental value was obtained, values for different clinical stages of cataracts were established. The time course of the development of radiation cataracts in mice subjected to X-ray irradiation in a wide spectrum of doses, was observed; clinical features of the process were revealed. Dose fractionation under the above conditions did not make aprotective effect on the lens. Dependence of a degree of lens injury on irradiation dose obtained owing to the use of the light transmission factor tau, was described with the following equation: N=Nsub(0)esup(-D/Dsup(0))

  10. Influence of acute hypoxia and radiation quality on cell survival

    Tinganelli, Walter; Ma, Ning-Yi; von Neubeck, Cläre; Maier, Andreas; Schicker, Corinna; Kraft-Weyrather, Wilma; Durante, Marco

    2013-01-01

    To measure the effect of acute oxygen depletion on cell survival for different types of radiation, experiments have been performed using Chinese hamster ovary (CHO) cells and RAT-1 rat prostate cancer cells. A special chamber has been developed to perform irradiations under different levels of oxygenation. The oxygen concentrations used were normoxia (air), hypoxia (94.5% N2, 5% CO2, 0.5% O2) and anoxia (95% N2, 5% CO2). Cells were exposed to X-rays and to C-, N- or O-ions with linear energy ...

  11. Radiation risk, medical surveillance programme and radiation protection in mining and milling of uranium ores

    Mining and milling of uranium ores comprise multiple operations such as developement, drilling, blasting, handling, crushing, grinding, leaching of the ore and concentration, drying, packaging and storing of the concentrate product. Apart from the hazards of any metal mining and milling operations due to dust, noise, chemicals, accidents etc there are radiation risks also resulting from exposure to airborne radioactivity and external radiation. The inhalation risk is of more concern in underground mines than in open pit mines. The objective of a Medical Surveillance Programme (an occupational Health Programme) is to ensure a healthy work force. It should ultimately lead to health maintenance and improvement, less absenteeism increased productivity and the achievement of worker and corporate goals. The programme includes prevention, acute care, counselling and rehabilitation. Radiological workers require special monitoring for their work-related radiation exposure effect by film monitoring service, whole body counting and bioassay. Radiation protection in the mining and milling of Uranium ores include the use of personal protective equipment, work station protection, personal hygiene and house keeping. (author). 15 refs

  12. Quantitative risk in radiation protection standards

    Although the overall aim of radiobiology is to understand the biological effects of radiation, it also has the implied practical purpose of developing rational measures for the control of radiation exposure in man. The emphasis in this presentation is to show that the enormous effort expended over the years to develop quantitative dose-effect relationships in biochemical and cellular systems, animals, and human beings now seems to be paying off. The pieces appear to be falling into place, and a framework is evolving to utilize these data. Specifically, quantitative risk assessments will be discussed in terms of the cellular, animal, and human data on which they are based; their use in the development of radiation protection standards; and their present and potential impact and meaning in relation to the quantity dose equivalent and its special unit, the rem

  13. Review of the controversy on risks from low levels of radiation

    The need for regulation of low levels of radiation exposure, and the estimation of risks from such exposures, are based on the assumption that risk is proportional to dose without a threshold, the 'linear no-threshold (LNT) hypothesis'. This assumption is not supported by scientific data. There is no clear evidence of harm from low levels of exposure, up to at least 20 mSv (acute dose) or total dose rates of at least 50 mSv per year. Even allowing for reasonable extrapolation from radiation levels at which harmful effects have been observed, the LNT assumption should not be used to estimate risks from doses less than 100 mSv. Laboratory and epidemiological evidence, and evolutionary expectations of biological effects from low level radiation, suggest that beneficial health effects (sometimes called 'radiation hormesis') are at least as likely as harmful effects from such exposures. Controversy on this matter strikes at the basis of radiation protection practice

  14. Risk factors in young patients of acute myocardial infarction

    Background: Ischemic heart disease is a leading cause of death throughout the world. CAD has been recognized among younger age group more frequently in recent years. Very limited data is available regarding the prevalence of various risk factors in our younger patients that is why this study was planed. Objectives of the study were to look for the risk factors most prevalent in our young patient of first Acute Myocardial Infarction. And to also look for the number of Risk Factors present in each patient. Methods: We studied 100 consecutive patients from 16-45 years of age presenting with first acute MI. Twelve risk factors were studied namely, gender, family history of premature CAD, smoking hypertension, diabetes, dyslipidemia, obesity, mental stress (type A personality), alcohol, oral contraceptive pills (OCPs), physical activity, and diet. We divided the patients into two groups. Group A with patients 35 years of age or less and group B with patients 36-45 years of age. All risk factors were compared in both the groups. Results: Smoking, diabetes mellitus, dyslipidemia and hypertension were statistically different between the two groups. Frequency wise risk factors were lined up as male sex (91%) Diet (66%), Dyslipidemia (62%), smoking (46%), Type A personality(46%), family history (32%), diabetes mellitus (28%), sedentary lifestyle (26%), hypertension (22%), obesity (17%), alcohol (3%), and OCPs (0%) Most of the patients that is 94% had 3 or more risk factors. Conclusion: Smoking, hypertension, diabetes and dyslipidemia are the major modifiable risk factors in our young adults. If a young male who is smoker or a young female who is diabetic, presents in emergency room with chest pain, always suspect coronary artery disease. Other conventional risk factors are also prevalent but alcohol and OCPs are not a major health problem for us. (author)

  15. The role of radiation therapy in childhood acute leukemia. A review from the viewpoint of basic and clinical radiation oncology

    Radiation therapy has been playing important roles in the treatment of childhood acute leukemia since the 1970s. The first is the preventive cranial irradiation for central nervous system therapy in acute lymphoblastic leukemia. The second is the total body irradiation as conditioning before bone marrow transplantation for children with acute myeloid leukemia in first remission and with acute lymphoblastic leukemia in second remission. Although some late effects have been reported, a part of them could be overcome by technical improvement in radiation and salvage therapy. Radiation therapy for children might have a successful outcome on a delicate balance between efficiencies and potential late toxicities. The role of radiation therapy for childhood acute leukemia was reviewed from the standpoint of basic and clinical radiation oncology in this paper. (author)

  16. Risk factors and outcomes of acute renal infarction

    Yang, Jihyun; Lee, Jun Yong; Na, Young Ju; Lim, Sung Yoon; Kim, Myung-Gyu; Jo, Sang-Kyung; Cho, Wonyong

    2016-01-01

    Background Renal infarction (RI) is an uncommon disease that is difficult to diagnose. As little is known about clinical characteristics of this disease, we investigated its underlying risk factors and outcomes. Methods We performed a retrospective single-center study of 89 patients newly diagnosed with acute RI between January 2002 and March 2015 using imaging modalities. Clinical features, possible etiologies, and long-term renal outcome data were reviewed. Results The patients' mean age wa...

  17. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures

  18. Anti-infection treatment of iatrogenic acute radiation sickness

    Objective: To occumulatle experience of anti-infection treatment in acute radiation sickness (ARS) induced by medical treatment in order to provide beneficial help for victims of accidental of acute radiation sickness. Methods: The changes of peripheral blood indices, body temperature and clinical symptoms of 17 cases who were clinically irradiated with 6.0-7.2 Gy X-rays were observed both before peripheral blood stem cell transplantation(PBSCT) and after anti-infection treatment. Results: WBC count began to decrease to below 1 x 109/L from the 8th to 10th days after irradiation and maintained at row level for 4 days or for 13.3 days if the patients had not received rhG-CSF treatment. In 29.4% of patients the body temperature was higher than 38.5 degree C. After comprehensive enviromental protection and anti-infection treatment, all patients could successfully tide over the period of bone marrow depression without appearance of the typical critical phase of ARS. Conclusion: PBSCT and rhG-CSF treatment can reduce the time span for reconstruction of bone marrow. Comprehensive enviromental protection and combined anti-infection treatment are key points fm successful treatment. (authors)

  19. Characteristics of long-term consequences of acute radiation sickness

    In persons who suffered from acute radiation sickness (ARS) as a result of the Chernobyl accident in course of time there are revealed the stochastic and non-stochastic effects of irradiation both in 'critical' and 'non-critical' organism systems. It is connected with maintenance of somatic mutation high level and steady changes in membranes subcellular structures, biomolecules as well as metabolic disturbances. Stable changes of hemopoietic and immune system indexes have to be considered as pre-pathological status with high hazard of stochastic effects development. Frequency rate of typical radiation cataracts (posterior subcapsular) is correlated with ARS severity degree; fundus oculi vessel pathology have essential weight in total eye pathology. Chronic radiation dermatitis is an important clinical problem being a long-term consequence of irradiation. It demands a constant attention in order to prevent trophic secondary skin lesions. Radiation damage of eye and skin as well as high frequency of chronic somatic diseases and neuropsychiatric disorders conditioned the high level of disablement in ARS-patients

  20. Assessment of recovery of the intestine after acute radiation injury

    Baer, A.R.; Cheeseman, C.I.; Thomson, A.B.

    1987-02-01

    Several aspects of intestinal function and morphology are affected by acute radiation damage, including changes in the activity of proliferative cells in the crypts, immune cell populations, and the transport of various substrates. This study was designed to compare the time course of the recovery of intestinal proliferation, transport, and leukocyte population following radiation injury. Rats received a single dose of 6 Gy to the abdomen from a /sup 137/Cs source and were studied 3, 7, and 14 days later. No changes in the passive uptake of L-glucose or D-leucine were observed in the jejunum. Active transport of D-glucose and maximal water uptake were reduced at 3 days but had returned to normal by 7 days, whereas L-leucine uptake required more than 7 days to return to control levels. Mucosal permeability, assessed by an in vivo potential difference technique, remained increased 7 days after irradiation. Ornithine decarboxylase, an indicator of DNA synthetic activity, was elevated following radiation treatment and remained so even after 14 days. By comparison, myeloperoxidase activity, used as a quantitative monitor of granulocyte numbers, was still reduced after 7 days. These data indicate that while certain parameters of gut function may return to normal soon after radiation injury, the recovery of other factors is more prolonged. Thus the return of transport function to normal values post irradiation may be viewed as an adaptive change rather than simply the recovery of the tissue.

  1. Radiation-induced hypopituitarism in children with acute lymphoblastic leukemia

    Mehrdad Mirouliaei

    2013-01-01

    Full Text Available Background: Acute Lymphoblastic Leukemia (ALL is the most common malignancy among children for whom radiotherapy and chemotherapy are used for treatment. When hypothalamus-pituitary axis is exposed to radiotherapy, children′s hormone level and quality of life are influenced. The aim of this study is to determine late effects of radiotherapy on hormonal level in these patients. Materials and Methods: In this study 27 children with ALL, who have been referred to Shahid Ramezanzadeh Radiation Oncology Center in Yazd-Iran and received 18-24 Gy whole brain radiation with Cobalt 60 or 9 MV linear accelerator, were assessed. These patient′s basic weight, height and hormonal levels were measured before radiotherapy and also after different periods of time. Results: GHD (growth hormone deficiency after clonidine stimulation test was observed in 44% ( n=12 and that in 50% of them ( n=6, less than 1 year, had been passed from their radiation therapy. None of these patients demonstrated hormone deficiency in other axes. Conclusions: This study showed that even application of a 18-24 Gy radiation dose might influence growth hormone levels; therefore, we recommend reduction of radiotherapy dose in such patients whenever possible.

  2. Radiation risk perception and public information

    We as Health Physicists face what, at many times, appears to be a hopeless task. The task simply stated is informing the public about the risks (or lack thereof) of radiation. Unfortunately, the public has perceived radiation risks to be much greater than they actually are. An example of this problem is shown in a paper by Arthur C. Upton. Three groups of people -- the League of Women Voters, students, and Business and Professional Club members -- were asked to rank 30 sources of risk according to their contribution to the number of deaths in the United States. Not surprisingly, they ranked nuclear power much higher and medical x-rays much lower than the actual values. In addition to the perception problem, we are faced with another hurdle: health physicists as communicators. Members of the Health Physics Society (HPS) found that the communication styles of most health physicists appear to be dissimilar to those of the general public. These authors administered the Myers-Briggs Type Indicator to the HPS Baltimore-Washington Chapter. This test, a standardized test for psychological type developed by Isabel Myers, ask questions that provide a quantitative measure of our natural preferences in four areas. Assume that you as a health physicist have the necessary skills to communicate information about radiation to the public. Health physicists do nothing with these tools. Most people involved in radiation protection do not get involved with public information activies. What I will attempt to do is heighten your interest in such activities. I will share information about public information activities in which I have been involved and give you suggestions for sources of information and materials. 2 refs., 1 tab

  3. Radiation risk perception and public information

    Boggs-Mayes, C.J.

    1988-01-01

    We as Health Physicists face what, at many times, appears to be a hopeless task. The task simply stated is informing the public about the risks (or lack thereof) of radiation. Unfortunately, the public has perceived radiation risks to be much greater than they actually are. An example of this problem is shown in a paper by Arthur C. Upton. Three groups of people -- the League of Women Voters, students, and Business and Professional Club members -- were asked to rank 30 sources of risk according to their contribution to the number of deaths in the United States. Not surprisingly, they ranked nuclear power much higher and medical x-rays much lower than the actual values. In addition to the perception problem, we are faced with another hurdle: health physicists as communicators. Members of the Health Physics Society (HPS) found that the communication styles of most health physicists appear to be dissimilar to those of the general public. These authors administered the Myers-Briggs Type Indicator to the HPS Baltimore-Washington Chapter. This test, a standardized test for psychological type developed by Isabel Myers, ask questions that provide a quantitative measure of our natural preferences in four areas. Assume that you as a health physicist have the necessary skills to communicate information about radiation to the public. Health physicists do nothing with these tools. Most people involved in radiation protection do not get involved with public information activies. What I will attempt to do is heighten your interest in such activities. I will share information about public information activities in which I have been involved and give you suggestions for sources of information and materials. 2 refs., 1 tab.

  4. Radiation exposure and radiation risk of the mammographic patient

    Depending on the technique applied the doses in the centre of the breast are significantly different. The dose reduction of a screen film grid combination is 50% compared with non-screen film. For the screen film combination alone it is significantly higher. The limited image quality of the gridless technique is not suited for primary examination. According to the present state of knowledge there are no reliable results about the radiation exposure of the breast in mammography and the induction of breast cancer. In a periodic mass screening the existing risk is significantly exceeded by the potential outcome. The care about the statistically calculated risk is irrelevant as to examinations within intervals of 1-2 years for women above 40. (author)

  5. Acute radiation syndrome, c.aused by single whole-body external irradiation

    The general characteristic of conceptions of the material substrate of various forms and types of radiation injuries from the moment of a wide use of radiation energy and radioactive substances up to the present time, the dependence of structural changes on the type of ionizing radiation, dose and forms of its effect, are presented. The pathological anatomy of particular manifestations of acute radiation disease in various systems of the organism is described. The attention is paid to the variant of radiation disease taking place during non-uniform general irradiation. Local and general morphological changes which develop in skin, hyperdermic fat and skeleton muscles simultaneously in the zone of massive local effect against the background of the general radiation injury, are described for the first time. Delayed alterations in blood vessels and interstitial tissue after the acute radiation disease are described as well as the pathomorphology and histochemistry of trophic disorders in the acute and delayed periods of acute radiation disease

  6. Esophageal toxicity of radiation therapy: Clinical risk factors and management

    Acute radiation-induced esophagitis includes all clinical symptoms (odynophagia, dysphagia) occurring within 90 days after thoracic irradiation start. Its severity can be graded using RTOG and CTCAE scales. The clinical risk factors are: age, female gender, initial performance status, pre-therapeutic body mass index, pre-therapeutic dysphagia, tumoral and nodal stage, delivered dose, accelerated hyperfractionated radiotherapy, concomitant association of chemotherapy to radiotherapy and response to the treatment. The dosimetric parameters predictive of esophagitis are: mean dose, V20 Gy, V30 Gy, V40 Gy, V45 Gy and V50 Gy. Amifostine is the only drug to have a proven radioprotective efficacy (evidence level C, ESMO recommendation grade III). The medical management of esophagitis associates a diet excluding irritant food, medication against gastroesophageal reflux, analgesic treatment according to the WHO scale and management of dehydration and de-nutrition by enteral feeding. (authors)

  7. DNA Damage Signals and Space Radiation Risk

    Cucinotta, Francis A.

    2011-01-01

    Space radiation is comprised of high-energy and charge (HZE) nuclei and protons. The initial DNA damage from HZE nuclei is qualitatively different from X-rays or gamma rays due to the clustering of damage sites which increases their complexity. Clustering of DNA damage occurs on several scales. First there is clustering of single strand breaks (SSB), double strand breaks (DSB), and base damage within a few to several hundred base pairs (bp). A second form of damage clustering occurs on the scale of a few kbp where several DSB?s may be induced by single HZE nuclei. These forms of damage clusters do not occur at low to moderate doses of X-rays or gamma rays thus presenting new challenges to DNA repair systems. We review current knowledge of differences that occur in DNA repair pathways for different types of radiation and possible relationships to mutations, chromosomal aberrations and cancer risks.

  8. Risk from deterministic effects of ionising radiation

    This publication provides a review of information for assessing deterministic effects on human health likely to arise from serious overexposure to ionising radiation. It updates information in previous Board publications NRPB-R226 and NRPB-M246. It constitutes a parallel document to Documents of the NRPB, 4, No. 4 (1993), which deals with stochastic effects. These two documents, together with Documents of the NRPB, 6, No. 1 (1995), which deals specifically with stochastic risk at low dose rates, give the current Board view on all health consequences of exposure to ionising radiation. Little new primary information on deterministic effects has become available in recent years. However, advances in techniques for data analysis have been made and are incorporated in the present report. These are presented in a form suitable for use in modelling the consequences to populations of serious radiological incidents. (author)

  9. Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

    Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author)

  10. Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

    Bouffler, S.D.; Breckon, G.; Cox, R. [National Radiological Protection Board, Chilton (United Kingdom)

    1996-04-01

    Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author).

  11. Radiation and health. Benefit and risks

    The book on radiation and health covers the following topics: The world of radiation and waves; a sight into biology; if radiation hits the body; a sight into the internal radiation diagnostics; radiation hazards; the not always beloved sun; mobile phones, microwave ovens and power poles; healing with and due to radiation; radiation and food; radiation in the environment; generation and interactions of radiation in more detail; radiation effects in the cell - closer insight; radiation doses and measurement; epidemiology and its pitfalls; the system of radiation protection radiation accidents.

  12. Hypofractionation does not increase radiation pneumonitis risk with modern conformal radiation delivery techniques

    Vogelius, Ivan R; Westerly, David C; Cannon, George M;

    2010-01-01

    To study the interaction between radiation dose distribution and hypofractionated radiotherapy with respect to the risk of radiation pneumonitis (RP) estimated from normal tissue complication probability (NTCP) models.......To study the interaction between radiation dose distribution and hypofractionated radiotherapy with respect to the risk of radiation pneumonitis (RP) estimated from normal tissue complication probability (NTCP) models....

  13. Antiradiation Antitoxin IgG : Immunological neutralization of Radiation Toxins at Acute Radiation Syndromes.

    Popov, Dmitri; Maliev, Slava

    Introduction: High doses of radiation induce apoptotic necrosis of radio-sensitive cells. Mild doses of radiation induce apoptosis or controlled programmed death of radio-sensitive cells with-out development of inflammation and formation of Radiation Toxins. Cell apoptotic necrosis initiates Radiation Toxins (RT)formation. Radiation Toxins play an important role as a trig-ger mechanism for inflammation development and cell lysis. If an immunotherapy approach to treatment of the acute radiation syndromes (ARS) were to be developed, a consideration could be given to neutralization of radiation toxins (Specific Radiation Determinants-SRD) by specific antiradiation antibodies. Therapeutic neutralization effects of the blocking anti-radiation antibodies on the circulated RT had been studied. Radiation Toxins were isolated from the central lymph of irradiated animals with Cerebrovascular(Cv ARS),Cardiovascular (Cr ARS),Gastrointestinal(Gi ARS) and Haemopoietic (Hp ARS) forms of ARS. To accomplish this objective, irradiated animals were injected with a preparation of anti-radiation immunoglobulin G (IgG) obtained from hyperimmune donors. Radiation-induced toxins that we call Specific Radiation Determinants (SRD) possess toxic (neurotoxic, haemotoxic) characteristics as well as specific antigenic properties. Depending on direct physiochemical radiation damage, they can induce development of many of the pathological processes associated with ARS. We have tested several specific hyperimmune IgG preparations against these radiation toxins and ob-served that their toxic properties were neutralized by the specific antiradiation IgGs. Material and Methods: A scheme of experiments was following: 1.Isolation of radiation toxins (RT) from the central lymph of irradiated animals with different form of ARS. 2.Transformation of a toxic form of the RT to a toxoid form of the RT. 3.Immunization of radiation naive animals. Four groups of rabbits were inoculated with a toxoid form of SRD

  14. Psychoneurological character of persons who had acute radiation syndrome

    Survivors of the Chernobyl accident who had an acute radiation syndrome (ARS,110 persons) were observed for 8 years after Chernobyl accident. It has been found that the cerebrovascular pathology and vertebral osteochondrosis rate increase as well as abnormal psychoorganic changes in personality and endogenic-like psychoorganic process, their rate being in proportion to the ARS heaviness. The EEG and evoked potentials have confirmed the dyscirculatory and toxic-metabolic organic disorders of the central nervous system as a result of irradiation in the remote period of the ARS consequences. It is necessary for early and differential diagnostic of the psychoneurological disorders after ARS to carry out the neuro- and psychophysiological examination as well as computer tomography, nucleic magnetic resonance and positron emission tomography of the brain

  15. Ionization radiations - basis, risks and benefits

    An attempt is made to discuss the use of ionizing radiations in an impartial way. Ionizing radiation is potentially harmfull; excessive doses have a devastating effect on living cells. However, there is no direct, conclusive evidence of human disability, either in the form of cancer or genetic anomalies, arising as a consequence of low-level doses of x- or gamma-rays of about 0.01 Gray (1 rad) the entire dose range involved in medical radiography or in nuclear industry. Statements appearing in the press that a certain number of excess cancers will be produced are estimates, based maybe on plausible assumptions, but estimates nevertheless; they are not measured quantities or established facts. A balanced view of radiation must include appreciation of the substantial benefits which result from their use in both medicine and industry. The risks are small and hard to demonstrate, and it is instructive to make a comparison with the other hazards occuring continually in an industrialized society, such as driving a motorcar or smoking cigarettes. (Author)

  16. Nuclear submarine decommissioning. Radiation risk assessments

    Decommissioning of the ships and vessels with nuclear power installations is a problem of primary and worldwide importance. It is essential for both the naval fleet and the military industrial complex as a whole. Nuclear submarines decommissioning is accompanied by a number of questions concerning the development and performance of the safe technologies for managing radioactive equipment and nuclear waste from the vessels with the nuclear power facilities. Decommissioning of nuclear submarines including unloading of the spent fuel should take place at the operating ship yards and repairing plants that are usually situated close to the densely populated areas and living blocks. Decommissioning includes a series of the potentially dangerous operations with radioactive materials, e.g. fuel unloading, disposal of coolant, dismantling of the contaminated equipment, cutting out the reactor compartment, etc. As a result a great amount of highly radioactive liquid and solid wastes are formed including the cut-out reactor compartment and spent fuel that produce additional radioactive load on the local environment and population. Estimation of the radiation risk for the environment and population due to decommissioning becomes an actual and necessary question. Apart from this the process of decommissioning may cause accidents followed by complicated radiation situation with high dose rates and contamination of the environment. Analysis of the most probable scenarios of the accident development and estimation of the expected radiation consequences should help to assess the risk rate for radiation impact on the environment and population as well as to develop an adequate environmental monitoring and to undertake measures for the accident localisation and liquidation of its consequences. A separate problem is management of the reactor compartment containing radioactive equipment of the steam producing installation and biological protection. Since there are no specialised

  17. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    Fabrikant, J.I.

    1982-08-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy.

  18. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy

  19. Countermeasures for Space Radiation Induced Malignancies and Acute Biological Effects

    Kennedy, Ann

    The hypothesis being evaluated in this research program is that control of radiation induced oxidative stress will reduce the risk of radiation induced adverse biological effects occurring as a result of exposure to the types of radiation encountered during space travel. As part of this grant work, we have evaluated the protective effects of several antioxidants and dietary supplements and observed that a mixture of antioxidants (AOX), containing L-selenomethionine, N-acetyl cysteine (NAC), ascorbic acid, vitamin E succinate, and alpha-lipoic acid, is highly effective at reducing space radiation induced oxidative stress in both in vivo and in vitro systems, space radiation induced cytotoxicity and malignant transformation in vitro [1-7]. In studies designed to determine whether the AOX formulation could affect radiation induced mortality [8], it was observed that the AOX dietary supplement increased the 30-day survival of ICR male mice following exposure to a potentially lethal dose (8 Gy) of X-rays when given prior to or after animal irradiation. Pretreatment of animals with antioxidants resulted in significantly higher total white blood cell and neutrophil counts in peripheral blood at 4 and 24 hours following exposure to doses of 1 Gy and 8 Gy. Antioxidant treatment also resulted in increased bone marrow cell counts following irradiation, and prevented peripheral lymphopenia following 1 Gy irradiation. Supplementation with antioxidants in irradiated animals resulted in several gene expression changes: the antioxidant treatment was associated with increased Bcl-2, and decreased Bax, caspase-9 and TGF-β1 mRNA expression in the bone marrow following irradiation. These results suggest that modulation of apoptosis may be mechanistically involved in hematopoietic system radioprotection by antioxidants. Maintenance of the antioxidant diet was associated with improved recovery of the bone marrow following sub-lethal or potentially lethal irradiation. Taken together

  20. An Overview of NASA's Risk of Cardiovascular Disease from Radiation Exposure

    Patel, Zarana S.; Huff, Janice L.; Simonsen, Lisa C.

    2015-01-01

    The association between high doses of radiation exposure and cardiovascular damage is well established. Patients that have undergone radiotherapy for primary cancers of the head and neck and mediastinal regions have shown increased risk of heart and vascular damage and long-term development of radiation-induced heart disease [1]. In addition, recent meta-analyses of epidemiological data from atomic bomb survivors and nuclear industry workers has also shown that acute and chronic radiation exposures is strongly correlated with an increased risk of circulatory disease at doses above 0.5 Sv [2]. However, these analyses are confounded for lower doses by lifestyle factors, such as drinking, smoking, and obesity. The types of radiation found in the space environment are significantly more damaging than those found on Earth and include galactic cosmic radiation (GCR), solar particle events (SPEs), and trapped protons and electrons. In addition to the low-LET data, only a few studies have examined the effects of heavy ion radiation on atherosclerosis, and at lower, space-relevant doses, the association between exposure and cardiovascular pathology is more varied and unclear. Understanding the qualitative differences in biological responses produced by GCR compared to Earth-based radiation is a major focus of space radiation research and is imperative for accurate risk assessment for long duration space missions. Other knowledge gaps for the risk of radiation-induced cardiovascular disease include the existence of a dose threshold, low dose rate effects, and potential synergies with other spaceflight stressors. The Space Radiation Program Element within NASA's Human Research Program (HRP) is managing the research and risk mitigation strategies for these knowledge gaps. In this presentation, we will review the evidence and present an overview of the HRP Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure.

  1. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    Fabrikant, J.I.

    1981-05-01

    The current knowledge of the carcinogenic effect of radiation in man is considered. The discussion is restricted to dose-incidence data in humans, particularly to certain of those epidemiological studies of human populations that are used most frequently for risk estimation for low-dose radiation carcinogenesis in man. Emphasis is placed solely on those surveys concerned with nuclear explosions and medical exposures. (ACR)

  2. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation.

    Fabrikant, J. I.

    1981-01-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer inducti...

  3. Informing people about radiation risks: a review of obstacles to public understanding and effective risk communication

    This paper reviews the literature on informing people about radiation risks. The paper focuses on obstacles to public understanding and effective risk communication. The paper concludes with a set of guidelines for communicating information about radiation risks to the public. The paper also includes an appendix that reviews the literature on one of the most important tools for communicating information about radiation risks: risk comparisons

  4. Risk factors of renal scars in children with acute pyelonephritis

    Fahimeh Ehsanipour

    2012-02-01

    Full Text Available OBJECTIVE: The aim of this study was to determine the association between previously documented risk factors such as recurrent pyelonephritis with the incidence of renal scarring after acute pyelonephritis in children. MATERIAL AND METHODS: Children with acute pyelonephritis who were admitted to the Department of Pediatrics of a teaching hospital during 2007-2009 were enrolled in this study. DMSA scans were obtained 4-6 months after the last episode of pyelonephritis in all patients. RESULTS: A total of 80 children with acute pyelonephritis were enrolled in this study. Most of them were girls (77.5%, with a median age of 12 months. Nearly half of the children (n = 44; 55% had one or more renal scars. The distribution of gender, CRP level and leukocytosis did not differ significantly regardingthe absence or presence of renal scars (p > 0.05. Most of the scars occurred in children who had presented with bilateral pyelonephritis (69.4% vs. 18.2%, p = 0.001. Most of the patients with renal scars had a positive history of vesicoureteral reflux (VUR (75% vs.13.6%, p = 0.001. The significant roles of recurrent pyelonephritis and presence of VUR were further confirmed by multivariate analysis. CONCLUSIONS: According to our findings, presence of VUR and recurrent pyelonephritis are independently associated with a higher incidence of renal scarring.

  5. Clinical Profile & Risk Factors in Acute Coronary Syndrome

    P Yadav, D Joseph, P Joshi, P Sakhi, RK Jha, J Gupta

    2010-12-01

    Full Text Available Coronary Artery Disease (CAD is becoming a major cause of morbidity & mortality burden in the developing world. Indians have been associated with a more severe form of CAD that has its onset at a younger age group with a male predominance. A prospective study was carried out to identify the risk factors and to know the emerging clinical profile in acute coronary syndrome (ACS including S T elevation & Non S T elevation myocardial infarction. We enrolled 200 consecutive patients with typical ECG changes & clinical history, admitted in emergency department from January 2009 to December 2009. A predefined Performa was completed in every patient with a detailed clinical history, physical examinations, and investigation studies. The clinical history revealed information about age, gender, risk factors, and modes of presentation and duration of symptoms. The details of physical examination including anthropometric data, vital signs and complete systemic evaluation were recorded. The regions of infarction and rhythm disturbances were also documented. Our study showed a significant male predominance with mean age being 56 years. Tobacco was identified as major risk factors (65% & obesity (BMI more than 25 is least common risk factor (13%.Patients had typical chest pain (94% and ECG showed anterior wall changes in54%. Forty percent patients developed complications, majority being arrhythmias (60% and least common is mechanical complication (2.5% Thus we conclude that ACS is more common in adult male with tobacco being major risk factors in our population.

  6. The acute radiation syndrome in the miniature pig Troll

    8 animals at an average age of 230 days and an average body weight of 24.9 kg were whole-body gamma-irradiated from a cobalt-60 source with 3.0 Gy midline dose. 4 of the 8 pigs survived, the others died within day 14 and 17 after irradiation, mainly due to thrombopenia dependent hemorrhage. Hematologic examinations showed as well that the platelets decreased to a minimum on day 14 p.r. The granulocyte values and yet remarkable the lymphocyte values decreased at an earlier time. The absolute lymphocyte counts reached their lowest mark already on the first day after irradiation. The reticulocytes, which also decreased markedly on day 1 p.r., sank further on the following days, till after two weeks when they started to increase again. Furthermore 25 biochemical serum parameters have been investigated. The major pathological findings of the acute radiation sickness were the mostly heavy hemorrhages. Histological studies indicated primarily aplasia of bone marrow, intestinal mucosa damages and atrophy of lymphatic tissues. Signs for septicemia were rarely found. The investigations in Troll-pigs showed, their reactions to an irradiation of middle-lethal doses are similar to those of other pigs. Only the Vietnamese pot-bellied swine reacts differently: Profuse diarrheas already after low radiation-doses are reported. (orig./MG)

  7. Copeptin for risk stratification in acute illness: beyond cardiological problems

    Roberto Cemin

    2013-10-01

    Full Text Available Copeptin (Cop has been recently proposed as a reliable marker for the diagnosis of acute coronary syndrome, altough its concentration was found to increase in a variety of other severe clinical conditions. The aim of the present study was to assess the utility of Cop to identify high-risk patients in the emergency room (ER. Eighty-five patients admitted to ER of the San Maurizio Regional Hospital of Bolzano between February to March 2010 with epigastric or chest pain and/or discomfort were included in the study. Blood was drawn at admission and sampled for Cop in standard laboratory tests. Cop levels were significantly higher in patients who died at the hospital or shortly afterwards as compared with survivors (median 61 vs 40.6 pmol/L; P=0.014. Cop levels were also higher in patients with severe health problems (62.9 vs 28.3 pmol/L; P<0.0001. The area under the receiver-operating characteristic curve of Cop was 0.70 for in-hospital death [95% confidence interval (CI 0.53-0.86], 0.74 for acute and subacute death (95% CI 0.61-0.87 and 0.90 for prediction of severe acute illness (95% CI 0.84-0.97. Accordingly, a Cop level >33.1 pmol/L correctly identified in-hospital death with 71% sensitivity and 74% specificity. A Cop level >13.6 pmol/L was instead associated with 89% sensitivity and 80% specificity for identifying patients with acute and severe conditions. The results of our analysis would suggest that the use of Cop may be a valuable aid in the ER for identifying patients with life-threatening conditions.

  8. Solid tumor risks after high doses of ionizing radiation

    Sachs, Rainer K; Brenner, David J.

    2005-01-01

    There is increasing concern regarding radiation-related second-cancer risks in long-term radiotherapy survivors and a corresponding need to be able to predict cancer risks at high radiation doses. Although cancer risks at moderately low radiation doses are reasonably understood from atomic bomb survivor studies, there is much more uncertainty at the high doses used in radiotherapy. It has generally been assumed that cancer induction decreases rapidly at high doses due to cell killing. However...

  9. Genomic alterations in radiation-induced murine acute myeloid leukemias

    High-dose radiation induces acute myeloid leukemia (AML) in C3H mice, most of which have a high frequent hemizygous deletion around the D2Mit15 marker on the interstitially deleted region of chromosome 2. This region involves PU.1 (Sfpi-1), which is a critical candidate gene for initiation of mouse leukemogenesis. To identify other genes contributing to leukemogenesis with PU.1, we analyzed chromosomal aberrations and changes of expression in 18 AML-related genes in 39 AMLs. Array CGH analysis revealed that 35 out of 39 AMLs had hemizygous deletions of chromosome 2, and recurrent aberrations on chromosomes 4, 6, 8, 10, 11, 12, 15, and 18. Expressions of 18 AML-related genes, within the altered chromosome regions detected by array CGH were analyzed by using RT-PCR and/or real-time PCR. Although Wnt5b, Wnt16, G-CSFR, M-CSFR, SCL/Tal-1 and GATA1 genes were down-regulated, the c-myc gene was, on the contrary, up-regulated. Expression levels of two genes, Rasgrp1 and Wt1, within the deleted region of chromosome 2 correlated with the loss of one of two alleles, although the expression of PU.1 showed an inverse correlation. In addition, the expression level of PU.1 appeared to be higher with a coincidental missense point mutation in DNA-binding domain of PU.1 in the remaining allele, suggesting a feedback transcription control on PU.1. Such an autoregulation might be relevant to the fact that PU.1 haploinsufficiency per se triggers radiation-induced AML. Together with the detection of chromosomal aberrations, these findings provide useful clues to identify cooperative genes that are responsible for molecular pathogenesis of AMLs induced by low-dose-rate radiation exposure. (author)

  10. Bile loss in the acute intestinal radiation syndrome in rats

    The effects of bile duct ligation (BDL), choledochostomy, bile acid sequestering within the intestinal lumen by cholestyramine, and fluid and electrolyte replacement on survival time and development of diarrhea after whole-body exposure to doses of ionizing radiation that result in death from acute intestinal injury were studied. BDL significantly prolonged survival and delayed the onset of diarrhea after exposure to 137Cs gamma rays, fission neutrons, or cyclotron-produced neutrons in the range of doses that produce intestinal death or death from a combination of intestinal and hematopoietic injuries. Cannulation of the bile duct with exteriorized bile flow (choledochostomy) to protect the irradiated intestine from the mucolytic action of bile salts did not duplicate the effect of BDL in increasing survival time. Choledochostomy without fluid replacement eliminated the occurrence of diarrhea in 15.4 Gy irradiated rats. Diarrhea did occur in irradiated animals with choledochostomy if they received duodenal injections of fluid and electrolytes to replace the fluid lost as a result of bile drainage. Duodenal injection of fluid and electrolytes had no significant effect on survival time in irradiated rats. Injection of fluid and electrolytes into the peritoneal cavity of irradiated rats resulted in an increase in survival time that was comparable to that observed after BDL. Addition of antibiotics to the peritoneally injected fluid and electrolytes further increased survival time (up to 9 days). This survival time approached that seen in animals receiving the same radiation dose but which had the intestine exteriorized and shielded to minimize radiation injury to the intestine. Postmortem histological examinations of the irradiated small intestine showed mucosal regeneration in these long-term survivors receiving fluid and antibiotic therapy

  11. Perforation rate in acute appendicitis: association with different risk facotrs

    B. Khorasani

    2006-08-01

    Full Text Available Background: The early diagnosis of acute appendicitis before progression to gangrene or abscess formation is recognized as important to minimize morbidity from this common disease process. The aim of this study was to assess the value of different risk factors in the diagnosis of perforation. Methods: This descriptive-analytic and retrospective study was conducted to investigate epidemiological characteristics in patients with perforated and non-perforated appendicitis. A series of 1311 patients who were operated on for acute appendicitis between years 1380-1382 in Shahid Beheshti and Yahya-nejad hospitals were reviewed.. Data gathered included age at operation, gender, care sought prior to admission for appendectomy including antibiotic and analgesic therapy, time of presentation in the year, duration of symptoms, signs and symptoms at the time of admission, and the patient’s living area. Results: One hundred twenty one of 1311 patients (9% had perforated appendicitis and 1190 patients (91% had unperforated appendicitis. Presentation and referral in the first 6-month was associated with higher perforation rate. Patients from rural area showed a higher rate of perforations. The perforation rate was significantly higher in elderly patients (>65 year. When the duration of symptoms was more than 12 hours at presentation, the risk of perforation showed a five-fold increase. 30.7% of perforated cases had used antibiotic or sedative before referring to the hospital. Conclusion: Appendiceal perforation continues to be a complication in patients with acute appendicitis and increased in the frequency as the age of the patients increase and the duration of symptoms lengthen. We also found that the perforation rate is higher in patients from rural area and in whom present in the first 6-month of the year, a finding that was not reported so far.

  12. Clofarabine in the treatment of poor risk acute myeloid leukaemia.

    Krawczyk, Janusz

    2010-09-01

    Clofarabine is a second generation nucleoside analogue. It inhibits DNA repair and activates the mitochondrial apoptotic pathway leading to cell death. In vitro clofarabine has demonstrated synergy with daunorubicin and Ara-C and in phase II clinical trials has shown promising activity in poor risk Acute myeloid leukaemia (AML) patients. In our institution over a 24 month period 22 AML patients (11 M, 11 F) with poor risk features, deemed unsuitable for standard therapy, were treated with clofarabine, alone (eight patients) or in combination (14 patients) for up to three cycles of treatment. The median age was 67.5 years (24-76) with 16 patients > 60 years. At the time of treatment 18 patients had active AML. Four patients intolerant of standard induction received clofarabine as consolidation. The overall response rate (ORR) for the 18 patients with active AML was 61%, nine patients (50%) achieving a complete response (CR). Induction and consolidation were well tolerated with no unexpected toxicities. Predictably, all patients developed grade 4 neutropenia but the median duration was only 20 days (17-120). Induction mortality was acceptable at 17%. In conclusion, clofarabine (alone or in combination) is active in poor risk AML with an acceptable safety profile and should be considered a potential option in poor risk AML patients.

  13. Review of the current status of radiation risk estimates

    This report reviews the current status of radiation risk estimation for low linear energy transfer radiation. Recent statements by various national and international organisations regarding risk estimates are critically discussed. The recently published revised population risk estimates from the study of Japanese bomb survivors are also reviewed and used with some unpublished data from Japan to calculate risk figures for a general work force. (author)

  14. Phase I trials involving radiation therapy, quantifying the risks

    Over one third of cancer patients receive radiation therapy (RT) at some point. Our purpose was to quantify the risks to patients associated with enrolment onto RT-based phase I trials. All phase I and phase I/II clinical trials involving RT published in English between 2001 and 2010 were identified via a PubMed search. For pragmatic reasons, we focused on trials from 2001, 2005 and 2009. For each trial we calculated a 'toxicity ratio' equal to the number of grade 3/4/5 toxic events divided by the number of patients in the trial. Linear regression was used to determine which variables were associated with higher toxicity ratios. There were a total of 33 treatment-related deaths, and 1812 acute grade 3/4 toxicities among the 2994 subjects in 98 trials. The median toxicity ratio over 98 trials was 0.46 (95% confidence interval (CI) 0.34 to 0.58). Multivariate regression analysis showed that toxicity ratios were significantly higher in trials with chemotherapy (P=0.002) and in trials for cancers of the head-and-neck (P<0.001). The median toxicity ratio in chemotherapy trials was 0.60 (95% CI: 0.48 to 0.72) compared with trials without chemotherapy 0.08 (95% CI: 0.03 to 0.13). Although the risk of grade 5 toxicity is low, the risk of major toxicity is significant in phase I RT trials. These values are comparable to published risk estimates for phase I non-RT trials.

  15. The role of MRI in the diagnosis of acute radiation reaction in breast cancer patient

    Startseva, Zh A.; Musabaeva, L. I.; Usova, AV; Frolova, I. G.; Simonov, K. A.; Velikaya, V. V.

    2016-02-01

    A clinical case with acute radiation reaction of the left breast after organ-preserving surgery with 10 Gy IORT (24.8 Gy) conventional radiation therapy has been presented. Comprehensive MRI examination showed signs of radiation- induced damage to skin, soft tissues and vessels of the residual breast.

  16. Comments on the theory of radiation risk I Systematic outline of the theory of radiation risk

    Neufeld, J

    1974-01-01

    Presents a systematic outline of the current theory of radiation risk. The most basic ideas of the theory can be expressed by two quantities which represent the administrative approach to radiation risk. These quantities are 'specific dose', D/sub s/, which relates to individual organs or tissues and 'overall dose', D/sub 0/, which relates to the entire human body. By taking D/sub s/ and D/sub 0/ as a starting point and by using postulational methods, two auxiliary quantities have been derived which are 'dose equivalent', D/sub e/(r), and quality factor, Q. Dose equivalent, D/sub e/(r), is a macroscopic field quantity and is, therefore, different from the ICRP defined dose equivalent, H, which is microscopic.

  17. The modes of death in mammals exposed to whole body radiation (acute radiation syndromes)

    When an animal is exposed to a sufficient amount of radiation, there will be changes in many organs of the body, and as a result of either the effects in one particular organ or the interaction of effects in several organs, the animal as a whole will show characteristic syndromes. Some syndromes result inevitably in death. Others may or may not be lethal, depending on the extent of the tissue damage. The time of appearance of the syndromes, their duration, and the survival of the organism depend on many factors. Whole body acute doses of radiation produce the same spectrum of Central Nervous System (CNS), Gastrointestinal (GI) and Bone Marrow (BM) injury in man as was described for animals. Damage to the skin, ovary and testis are an integral and important part of the symptoms. (author)

  18. Clinical effect of rhEGF on acute radiation stomatitis

    Objective: To evaluate the clinical effect of recombinant human epidermal growth factor (rhEGF) on acute radiation stomatitis (ARS). Methods: A total of 90 patients with head and neck malignant tumor going to receive radiotherapy were randomized into 3 groups: prophylactic application group (group A); therapeutic application group (group B) and the control group(group C). The irradiated mucous membrane was sprayed with rhEGF at the beginning of radiotherapy in group A and sprayed after grade I radiation stomatitis had appeared in group B. Comparison was made with control patients (group C) who received routine oral care with Dobell's solution. The rate of ARS and the clinical effect of rhEGF were evaluated. Results: The ARS appeared in 73% (22/30) of the patients after irradiated at a dose more than 10 Gy in group A, and appeared in 83% (25/30) of the patients irradiated at a dose less than 10 Gy in group C. In groups A and B, the rates of grades III and IV ARS were obviously lower than those in group C. The average curative time of the rhEGF treatment groups (group A or B) was less than 7 days whereas, that of the control group (group C) was more than 10 days. The total effective rate of the rhEGF treatment groups was significantly higher than that of the control group (P<0.01). Conclusion: Prophylactic application of rhEGF can postpone the development of ARS. rhEGF can reduce the incidence of grades III and IV of ARS and shorten the curative time of ARS by either prophylactic or therapeutic application. Therefore, it should be highly recommended and popularized. (authors)

  19. Evaluating shielding effectiveness for reducing space radiation cancer risks

    We discuss calculations of probability distribution functions (PDF) representing uncertainties in projecting fatal cancer risk from galactic cosmic rays (GCR) and solar particle events (SPE). The PDFs are used in significance tests for evaluating the effectiveness of potential radiation shielding approaches. Uncertainties in risk coefficients determined from epidemiology data, dose and dose-rate reduction factors, quality factors, and physics models of radiation environments are considered in models of cancer risk PDFs. Competing mortality risks and functional correlations in radiation quality factor uncertainties are included in the calculations. We show that the cancer risk uncertainty, defined as the ratio of the upper value of 95% confidence interval (CI) to the point estimate is about 4-fold for lunar and Mars mission risk projections. For short-stay lunar missions (180d) or Mars missions, GCR risks may exceed radiation risk limits that are based on acceptable levels of risk. For example, the upper 95% CI exceeding 10% fatal risk for males and females on a Mars mission. For reducing GCR cancer risks, shielding materials are marginally effective because of the penetrating nature of GCR and secondary radiation produced in tissue by relativistic particles. At the present time, polyethylene or carbon composite shielding cannot be shown to significantly reduce risk compared to aluminum shielding based on a significance test that accounts for radiobiology uncertainties in GCR risk projection

  20. Evaluating Shielding Effectiveness for Reducing Space Radiation Cancer Risks

    Cucinotta, Francis A.; Kim, Myung-Hee Y.; Ren, Lei

    2007-01-01

    We discuss calculations of probability distribution functions (PDF) representing uncertainties in projecting fatal cancer risk from galactic cosmic rays (GCR) and solar particle events (SPE). The PDF s are used in significance tests of the effectiveness of potential radiation shielding approaches. Uncertainties in risk coefficients determined from epidemiology data, dose and dose-rate reduction factors, quality factors, and physics models of radiation environments are considered in models of cancer risk PDF s. Competing mortality risks and functional correlations in radiation quality factor uncertainties are treated in the calculations. We show that the cancer risk uncertainty, defined as the ratio of the 95% confidence level (CL) to the point estimate is about 4-fold for lunar and Mars mission risk projections. For short-stay lunar missions (risk, however one that is mitigated effectively by shielding, especially for carbon composites structures with high hydrogen content. In contrast, for long duration lunar (>180 d) or Mars missions, GCR risks may exceed radiation risk limits, with 95% CL s exceeding 10% fatal risk for males and females on a Mars mission. For reducing GCR cancer risks, shielding materials are marginally effective because of the penetrating nature of GCR and secondary radiation produced in tissue by relativistic particles. At the present time, polyethylene or carbon composite shielding can not be shown to significantly reduce risk compared to aluminum shielding based on a significance test that accounts for radiobiology uncertainties in GCR risk projection.

  1. IS OPIUM ADDICTION A RISK FACTOR FOR ACUTE MYOCARDIAL INFARCTION?

    "S. M. Sadr Bafghi

    2005-06-01

    Full Text Available There is a misconception among our people that opioids may prevent or have ameliorating effects in the occurrence of cardiovascular diseases. In this study we evaluated 556 consecutive male patients hospitalized due to acute myocardial infarction (MI in city of Yazd, from May 2000 to October 2001 and compared the characteristics of opium addicts to non opium users. Prevalence of opium addiction in MI patients was 19% in comparison with 2-2.8% in general population. There were not any differences in prevalence of traditional risk factors between opium users and non-users. Overall, in-hospital mortality was 18.6 percent among opium users and 6.2 percent among non-opium users (unadjusted odd ratio, 1.3; 95% confidence interval, 0.7 to 2.7, P = 0.2. After adjustment for the differences in the baseline features (age and other risk factors, odds ratio increased to 2.2 (95 percent confidence interval, 0.9 to 5.1. It seems that opium addiction may work as a risk factor in cardiovascular disease.

  2. Influence of acute hypoxia and radiation quality on cell survival

    The purpose of this study was to measure the effect of acute oxygen depletion on cell survival for different types of radiation, experiments have been performed using Chinese hamster ovary (CHO) cells and R-3327-AT1 (RAT-1) rat prostate cancer cells. A special chamber has been developed to perform irradiations under different levels of oxygenation. The oxygen concentrations used were normoxia (air), hypoxia (94.5% N2, 5% CO2, 0.5% O2) and anoxia (95% N2, 5% CO2). Cells were exposed to X-rays and to C-, N- or O-ions with linear energy transfer (LET) values ranging from 100-160 keV/μm. The oxygen enhancement ratio (OER) and relative biological effectiveness (RBE) values have been calculated from the measured clonogenic survival curves. For both cell lines, the X-ray OER depended on the survival level. For particle irradiation, OER was not dependent on the survival level but decreased with increasing LET. The RBE of CHO cells under oxic conditions reached a plateau for LET values above 100 keV/μm, while it was still increasing under anoxia. In conclusion, the results demonstrated that our chamber could be used to measure radiosensitivity under intermediate hypoxia. Measurements suggest that ions heavier than carbon could be of additional advantage in the irradiation, especially of radioresistant hypoxic tumor regions. (author)

  3. Knowledge of medical imaging radiation dose and risk among doctors

    The growth of computed tomography (CT) and nuclear medicine (NM) scans has revolutionised healthcare but also greatly increased population radiation doses. Overuse of diagnostic radiation is becoming a feature of medical practice, leading to possible unnecessary radiation exposures and lifetime-risks of developing cancer. Doctors across all medical specialties and experience levels were surveyed to determine their knowledge of radiation doses and potential risks associated with some diagnostic imaging. A survey relating to knowledge and understanding of medical imaging radiation was distributed to doctors at 14 major Queensland public hospitals, as well as fellows and trainees in radiology, emergency medicine and general practice. From 608 valid responses, only 17.3% correctly estimated the radiation dose from CT scans and almost 1 in 10 incorrectly believed that CT radiation is not associated with any increased lifetime risk of developing cancer. There is a strong inverse relationship between a clinician's experience and their knowledge of CT radiation dose and risks, even among radiologists. More than a third (35.7%) of doctors incorrectly believed that typical NM imaging either does not use ionising radiation or emits doses equal to or less than a standard chest radiograph. Knowledge of CT and NM radiation doses is poor across all specialties, and there is a significant inverse relationship between experience and awareness of CT dose and risk. Despite having a poor understanding of these concepts, most doctors claim to consider them prior to requesting scans and when discussing potential risks with patients.

  4. Variability in the natural radiation dose as a point of comparison for judging acceptable radiation risk

    The Recommendations of the International Commission on Radiological Protection use, as a valid method for judging the acceptability of the level of risk due to occupational radiation exposure, a comparison of work-related radiation risks with risks in other occupations recognized as having high standards of safety. Recently the Food and Drug Administration evaluated various rationales on which to base Protective Action Guides (PAGs). PAGs are guides or numerical limits for actions, to be taken in the event of a radiological incident resulting in the contamination of human food or animal feeds. As with the ICRP's recommendations the PAGs have been formulated on the basis of a judgement of acceptable risk. One approach for making this judgement is to compare the risk of radiation exposure with the risk of other common hazards accepted by society. This approach is similar to that employed by the ICRP. Another method of comparison, described in this paper, uses the variability of natural radiation exposure for evaluating the acceptability of radiation risk. This comparison yields more conservative numerical limits than comparison to common societal hazards. This comparison is appropriate in that the geographic variability in natural radiation exposure is normally discounted as a risk in a highly mobile society. Further, in this analysis radiation risks are directly compared rather than comparing radiation with non-radiation risks, as is the case for analyses employing societal hazards as a baseline reference. (author)

  5. Use of methimazole and risk of acute pancreatitis: A case–control study in Taiwan

    Shih-Wei Lai

    2016-01-01

    Conclusions: Our study does not detect a substantial association between the use of methimazole and risk of acute pancreatitis on the basis of systematic analysis. There appears to be a discrepancy between case reports and our systematic analysis about the association between the use of methimazole and risk of acute pancreatitis.

  6. The acute radiation syndrome in the 137Cs Brazilian accident, 1987

    Eight patients with the most severe degreed of bone marrow impairment are studied. Case descriptions are limited to manifestations and complications related to the 'Acute Radiation Syndrome' (ARS). Medical facilities, exams and therapeutic management are discussed. (MAC)

  7. Characteristics of KIPT staff by groups of radiation risk

    The methodology of individual radiation cancer risk assessment UNSCEAR-94 has been described. Characteristics of KIPT staff at the individual monitoring, in terms of the ''Dose-response matrix'' have been reviewed. The main results of the calculations of the relative, attributive and absolute radiation risks of KIPT personnel for different sites and different risk groups have been showed. The distributions of the main characteristics of the personnel: age, years on the individual monitoring and the cumulative dose for different radiation risk groups of staff have been investigated.

  8. Risk Stratification and Management of Patients with Acute Myocardial Infarction (AMI)

    Peleška, Jan; Grünfeldová, H.; Faltus, Václav; Monhart, Z.; Ryšavá, D.; Velimský, T.; Ballek, L.; Hubač, J.; Tomečková, Marie; Janský, P.

    Timisoara: Cardiology Clinic of the Emergency County Hospital, 2007. s. 28-29. [International Workshop on the Risk Stratification in Patients with Ischemic Heart Disease. 12.04.2007-13.04.2007, Timisoara] R&D Projects: GA MŠk(CZ) 1M06014 Institutional research plan: CEZ:AV0Z10300504 Keywords : pilot registry of acute myocardial infarction * risk stratification in acute myocardial infarction * effects of pharmacotherapy in acute myocardial infarction Subject RIV: BB - Applied Statistics, Operational Research

  9. Risk estimation for badge-monitored radiation workers.

    Stewart, A.

    1997-01-01

    In estimating the cancer mortality risk for radiation workers it is conventional to use data obtained from the populations exposed to radiation as a result of the atomic bomb blast in Hiroshima and Nagasaki. This A-bomb experience resulted in relatively high doses of radiation and short periods of exposure. The availability of systematic analyses of the mortality of workers at the Hanford plant (Washington state) provides a more realistic basis for individual risk estimates. We present the da...

  10. Acceptable level of radiation risk and its perception

    The acceptable level of radiation risk for public members, that is 10-5/y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10-5/y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10-5/y as acceptable risk level in Japan. The perception to risk level of 10-5/y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one. (author)

  11. Radiation education to medical residents. Their understanding and risk perception of radiation

    The improvement of radiation education to medical staffs is required in particular after the nuclear accident at the TEPCO Fukushima Daiichi nuclear power station; however, the comprehension level of radiation by medical doctors has not been elucidated. Here we analyzed the understanding and risk perception of radiation by the medical residents by the results of the review examination and the questionnaire in the radiation education course for them from 2011 to 2014. Although the health effect of radiation was relatively well understood compared to the basics, safe handling, and legal issues, some primary and simple questions in all areas resulted in exceptionally low scores. The risk perception of radiation was high in the nuclear power generation and low in the medical radiation, which appeared stable in every year and similar to the radiation risk perception by other respondents. These findings suggest that the repeated education course for medical staffs is absolutely necessary to make them better understand radiation and updated continuously. (author)

  12. Salivary biochemical markers as potential acute toxicity parameters for acute radiation injury: A study on small experimental animals.

    Soni, S; Agrawal, P; Kumar, N; Mittal, G; Nishad, D K; Chaudhury, N K; Bhatnagar, A; Basu, M; Chhillar, N

    2016-03-01

    Researchers have been evaluating several biodosimetric/screening approaches to assess acute radiation injury, related to mass causality. Keeping in mind this background, we hypothesized that effect of whole-body irradiation in single fraction in graded doses can affect the secretion of various salivary components that could be used as acute radiation injury/toxicity marker, which can be used in screening of large population at the time of nuclear accidents/disaster. Thirty Sprague Dawley rats treated with whole-body cobalt-60 gamma irradiation of dose 1-5 Gy (dose rate: 0.95 Gy/min) were included in this study. Whole mixed saliva was collected from all animals before and after radiation up to 72 h postradiation. Saliva was analyzed for electrolytes, total protein, urea, and amylase. Intragroup comparison of salivary parameters at different radiation doses showed significant differences. Potassium was significantly increased as the dose increased from 1 Gy to 5 Gy (p 0.5). Sodium was significantly altered after 3-5 Gy (p 0.5), except 1 and 2 Gy, whereas changes in sodium level were nonsignificant (p > 0.5). Urea, total protein, and amylase levels were also significantly increased as the radiation dose increased (p 0.5). This study suggests that salivary parameters were sensitive toward radiation even at low radiation dose which can be used as a predictor of radiation injury. PMID:25813962

  13. Radiation risk for women undergoing mammography examinations

    Full text of publication follows: Introduction: The application of X-rays in mammography examinations requires not only constant control of physical and technical parameters of the equipment used, but also an evaluation of the radiation risk for patients, particularly in mammography screening programs. There exist a number of methods of dose evaluation in mammography. Some of them are included in the dosimetry protocols. The tolerances for measured values, limiting the dose to the patients have also been established. One of the methods, proposed by Dance, applies to establishing the doses to individual patients. It requires the knowledge clinical and exposition parameters. Another method, recommended by the E.C., requires establishing the phantom dose for reference exposition, as part of quality control tests. This approach is simpler but less precise, because at most mammography facilities the conditions of reference exposition are different than those of routine clinical exposition as it was shown in an exercise of quality control tests in a group of 32 mammography facilities in Poland. The method proposed in this study is an intermediate solution recommending measurement of phantom dose for the routine clinical exposition. Material and Methods: The material contains the data of 230 expositions performed in 6 mammography facilities Poland. This data was used to establish individual dose for ever y patient undergoing mammography examination according to the method proposed by Dance. For each mammography facility the mean glandular dose (M.G.D. F.) was established for reference and routine expositions according to the E.C. Dosimetry Protocol. The limits for phantom dose were established, which, according to the E.C. protocol, depend on the optical density (over background) of the image of the PMMA phantom 4.5 cm thick. Results and Discussion: The phantom dose determined for each mammography facility were below the limits. The lowest value of the mean dose received

  14. Copper sulfate acute ecotoxicity and environmental risk for tropical fish

    Adilson Ferreira da Silva

    2014-10-01

    Full Text Available The aim of this study was to estimate copper sulfate acute toxicity and to determine death percentage and environmental risk on guppy fish (Phallocerus caudimaculatus, zebrafish (Brachydanio rerio, mato grosso (Hyphessobrycon eques, and pacu (Piaractus mesopotamicus. Fish were exposed to 0.01, 0.03, 0.05, 0.07, 0.10, and 0.30 mg L-1 (guppy, 0.05, 0.07, 0.10, and 0.30 mg L-1 (zebrafish, 0.07, 0.10, 0.20, and 0.30 mg L-1 (mato grosso and 9.5, 10.0, 10.5, 11.0, 11.5, and 12.0 mg L-1 (pacu of copper sulfate, with triplicate control. The estimated 50% average lethal concentrations (LC50; 96 hours were 0.05 (guppy, 0.13 (zebrafish; 0.16 (mato grosso and 10.36 mg L-1 (pacu. Copper sulfate was extremely toxic for guppy, highly toxic for zebrafish and mato grosso and lightly toxic for pacu and presents environmental risk of high adverse effects on the guppy, zebrafish and mato grosso and moderate adverse effect to the pacu. Therefore, the guppy fish, zebrafish, and mato grosso are important alternatives for copper sulfate toxicity evaluation in waterbodies.

  15. Minimizing Astronauts' Risk from Space Radiation during Future Lunar Missions

    Kim, Myung-Hee Y.; Hayat, Mathew; Nounu, Hatem N.; Feiveson, Alan H.; Cucinotta, Francis A.

    2007-01-01

    This viewgraph presentation reviews the risk factors from space radiation for astronauts on future lunar missions. Two types of radiation are discussed, Galactic Cosmic Radiation (GCR) and Solar Particle events (SPE). Distributions of Dose from 1972 SPE at 4 DLOCs inside Spacecraft are shown. A chart with the organ dose quantities is also given. Designs of the exploration class spacecraft and the planned lunar rover are shown to exhibit radiation protections features of those vehicles.

  16. Space Radiation: The Number One Risk to Astronaut Health beyond Low Earth Orbit

    Jeffery C. Chancellor

    2014-09-01

    Full Text Available Projecting a vision for space radiobiological research necessitates understanding the nature of the space radiation environment and how radiation risks influence mission planning, timelines and operational decisions. Exposure to space radiation increases the risks of astronauts developing cancer, experiencing central nervous system (CNS decrements, exhibiting degenerative tissue effects or developing acute radiation syndrome. One or more of these deleterious health effects could develop during future multi-year space exploration missions beyond low Earth orbit (LEO. Shielding is an effective countermeasure against solar particle events (SPEs, but is ineffective in protecting crew members from the biological impacts of fast moving, highly-charged galactic cosmic radiation (GCR nuclei. Astronauts traveling on a protracted voyage to Mars may be exposed to SPE radiation events, overlaid on a more predictable flux of GCR. Therefore, ground-based research studies employing model organisms seeking to accurately mimic the biological effects of the space radiation environment must concatenate exposures to both proton and heavy ion sources. New techniques in genomics, proteomics, metabolomics and other “omics” areas should also be intelligently employed and correlated with phenotypic observations. This approach will more precisely elucidate the effects of space radiation on human physiology and aid in developing personalized radiological countermeasures for astronauts.

  17. Medical interventional procedures--reducing the radiation risks

    Over the last 40 years, the number of percutaneous interventional procedures using radiation has increased significantly, with many secondary care clinicians using fluoroscopically guided techniques. Many procedures can deliver high radiation doses to patients and staff, with the potential to cause immediate and delayed radiation effects. The challenge for interventionists is to maximize benefit, whilst minimizing radiation risk to patients and staff. Non-radiologist clinicians are often inadequately trained in radiation safety and radiobiology. However, clinical governance and legislation now requires a more rigorous approach to protecting patients and staff. Protection can be ensured, and risks can be controlled, by appropriate design, procurement and commissioning of equipment; quality assurance; and optimal operational technique, backed by audit. Interventionists need knowledge and skills to reduce the risks. Appropriate training should include awareness of the potential for radiation injury, equipment operational parameters, doses measurement and recording methods and dose reduction techniques. Clinical governance requires informed consent, appropriate patient counselling and follow-up

  18. Role of toll-like receptors in acute gastrointestinal radiation syndrome

    Ionizing radiation induces various disorders according to the radiation sensitivity of each organ. Acute gastrointestinal radiation syndrome is a serious illness that is caused by exposure of gastrointestinal tract to high amounts of ionizing radiation in radiation accidents or radiation therapy in cancer treatment. Although the pathological mechanism have been well studied in human and animals, no effective treatments have been developed to date. The Toll-like receptor (TLR) family is one of the best-characterized families of innate immune receptors, which induce innate immune response against pathogen infection. However, contrary to their protective function, recent studies have suggested that immune responses triggered by TLRs play deleterious roles by aggravating tissue inflammation in some inflammatory and autoimmune diseases. This review describes recent advancement of our understanding of acute gastrointestinal radiation syndrome and the contributions of TLR to its pathological mechanisms. (author)

  19. The Increase in Animal Mortality Risk following Exposure to Sparsely Ionizing Radiation Is Not Linear Quadratic with Dose

    Haley, Benjamin M.; Tatjana Paunesku; David J Grdina; Woloschak, Gayle E.

    2015-01-01

    Introduction The US government regulates allowable radiation exposures relying, in large part, on the seventh report from the committee to estimate the Biological Effect of Ionizing Radiation (BEIR VII), which estimated that most contemporary exposures- protracted or low-dose, carry 1.5 fold less risk of carcinogenesis and mortality per Gy than acute exposures of atomic bomb survivors. This correction is known as the dose and dose rate effectiveness factor for the life span study of atomic bo...

  20. Computed tomographic findings of radiation-induced acute adrenal injury with associated radiation nephropathy: a case report

    Radiation nephropathy was first recognized in 1906. The kidney is a radiosensitive organ with a tolerance dose (5% complications in 5 years) of 20 Gray. The imaging findings of acute and chronic radiation induced renal injury are previously described. Radiation-induced adrenal injury, to our knowledge, has not been described in the literature. Unlike the kidneys and other upper abdominal organs, the adrenal glands are traditionally thought to be radio-resistant, protected from radiation-induced injury by proximity to adjacent organs and by the adrenal medulla which reportedly has increased radio-resistance. We present the computed tomographic imaging findings of a patient with acute radiation induced adrenal injury which resulted in adrenal insufficiency following radiotherapy of an adjacent thecal metastasis

  1. Acceptability of risk from radiation: Application to human space flight

    NONE

    1997-04-30

    This one of NASA`s sponsored activities of the NCRP. In 1983, NASA asked NCRP to examine radiation risks in space and to make recommendations about career radiation limits for astronauts (with cancer considered as the principal risk). In conjunction with that effort, NCRP was asked to convene this symposium; objective is to examine the technical, strategic, and philosophical issues pertaining to acceptable risk and radiation in space. Nine papers are included together with panel discussions and a summary. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  2. Acceptability of risk from radiation: Application to human space flight

    This one of NASA's sponsored activities of the NCRP. In 1983, NASA asked NCRP to examine radiation risks in space and to make recommendations about career radiation limits for astronauts (with cancer considered as the principal risk). In conjunction with that effort, NCRP was asked to convene this symposium; objective is to examine the technical, strategic, and philosophical issues pertaining to acceptable risk and radiation in space. Nine papers are included together with panel discussions and a summary. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database

  3. Risk stratification in non-ST elevation acute coronary syndromes: Risk scores, biomarkers and clinical judgment

    David Corcoran

    2015-09-01

    Clinical guidelines recommend an early invasive strategy in higher risk NSTE-ACS. The Global Registry of Acute Coronary Events (GRACE risk score is a validated risk stratification tool which has incremental prognostic value for risk stratification compared with clinical assessment or troponin testing alone. In emergency medicine, there has been a limited adoption of the GRACE score in some countries (e.g. United Kingdom, in part related to a delay in obtaining timely blood biochemistry results. Age makes an exponential contribution to the GRACE score, and on an individual patient basis, the risk of younger patients with a flow-limiting culprit coronary artery lesion may be underestimated. The future incorporation of novel cardiac biomarkers into this diagnostic pathway may allow for earlier treatment stratification. The cost-effectiveness of the new diagnostic pathways based on high-sensitivity troponin and copeptin must also be established. Finally, diagnostic tests and risk scores may optimize patient care but they cannot replace patient-focused good clinical judgment.

  4. Diagnostic criterions of the postradiation encephalopathy in remote period of the acute radiation syndrome

    Development of post-radiation encephalopathy diagnostic criteria on the base of neuro psychic, neuro- and psychofisiological research in patients who suffered with acute radiation disease after Chernobyl catastrophe was the aim of this work. 110 persons of 20-75 years age were investigated. 55 refs., 6 tab., 6 figs

  5. Granulocyte Colony-Stimulating Factor in the Treatment of Acute Radiation Syndrome: A Concise Review

    Hofer, Michal; Pospíšil, Milan; Komůrková, Denisa; Hoferová, Zuzana

    2014-01-01

    Roč. 19, č. 4 (2014), s. 4770-4778. ISSN 1420-3049 R&D Projects: GA ČR(CZ) GAP303/11/0128 Institutional support: RVO:68081707 Keywords : granulocyte colony-stimulating factor * radiation accidents * acute radiation syndrome Subject RIV: BO - Biophysics Impact factor: 2.416, year: 2014

  6. Thymus endocrine function in acute radiation sickness resulted from Chernobyl accident

    Data are presented on the role of inhibition of endocrine function of the thymus in the pathogenesis of acute radiation sickness resulted from the direct and indirect (via the increased glucocorticoid production) effects of ionizing radiation. The complex treatment, including nonspecific active immunotherapy, permitted to normalize the thymic hormone level and certain parameters of the immune system

  7. Acute and late toxicity in prostate cancer patients treated by dose escalated intensity modulated radiation therapy and organ tracking

    To report acute and late toxicity in prostate cancer patients treated by dose escalated intensity-modulated radiation therapy (IMRT) and organ tracking. From 06/2004 to 12/2005 39 men were treated by 80 Gy IMRT along with organ tracking. Median age was 69 years, risk of recurrence was low 18%, intermediate 21% and high in 61% patients. Hormone therapy (HT) was received by 74% of patients. Toxicity was scored according to the CTC scale version 3.0. Median follow-up (FU) was 29 months. Acute and maximal late grade 2 gastrointestinal (GI) toxicity was 3% and 8%, late grade 2 GI toxicity dropped to 0% at the end of FU. No acute or late grade 3 GI toxicity was observed. Grade 2 and 3 pre-treatment genitourinary (GU) morbidity (PGUM) was 20% and 5%. Acute and maximal late grade 2 GU toxicity was 56% and 28% and late grade 2 GU toxicity decreased to 15% of patients at the end of FU. Acute and maximal late grade 3 GU toxicity was 8% and 3%, respectively. Decreased late ≥ grade 2 GU toxicity free survival was associated with higher age (P = .025), absence of HT (P = .016) and higher PGUM (P < .001). GI toxicity rates after IMRT and organ tracking are excellent, GU toxicity rates are strongly related to PGUM

  8. Interaction between radiation and other breast cancer risk factors

    A follow-up study was conducted of 1764 women institutionalized for pulmonary tuberculosis between 1930 and 1954. Among 1047 women exposed to fluoroscopic chest X-rays during air collapse therapy of the lung, an excess of breast cancer was observed and previously reported (41 cases observed versus 23.3 expected). Among 717 comparison patients who received other treatments, no excess breast cancer risk was apparent (15 cases observed versus 14.1 expected). To determine whether breast cancer risk factors modify the carcinogenic effect of radiation, analyses were performed evaluating the interaction of radiation with indicators of breast cancer risk. The greatest radiation risk was found when radiation exposure occurred just before and during menarche. Similarly, exposures during first pregnancy appeared substantially more hazardous than exposures occurring before or after first pregnancy, suggesting that the condition of the breast at the time of pregnancy modifies the effect of radiation in such a way as to enhance the risk. Age at menopause did not appear to influence the risk of radiation exposure. Other than radiation, benign breast disease was the most significant breast cancer risk indicator. Benign breast disease was not seen to modify the effect of radiation exposure; however, excessive radiation exposure might have increased the incidence of benign breast disease, complicating the interaction analysis. Because of the uncertainty due to small-number sampling variation, these study results will require confirmation by a larger series. They do, however, suggest that stages when breast tissue undergoes high mitotic activity, e.g. menarche and pregnancy, are times of special vulnerability to the harmful effects of ionizing radiation

  9. Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation

    Daila S. Gridley, PhD

    2012-03-30

    FINAL TECHNICAL REPORT Supported by the Low Dose Radiation Research Program, Office of Science U.S. Department of Energy Grant No. DE-FG02-07ER64345 Project ID: 0012965 Award Register#: ER64345 Project Manager: Noelle F. Metting, Sc.D. Phone: 301-903-8309 Division SC-23.2 noelle.metting@science.doe.gov Submitted March 2012 To: https://www.osti.gov/elink/241.3.jsp Title: Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation PI: Daila S. Gridley, Ph.D. Human low dose radiation data have been derived primarily from studies of space and airline flight personnel, nuclear plant workers and others exposed occupationally, as well as victims in the vicinity of atomic bomb explosions. The findings remain inconclusive due to population inconsistencies and complex interactions among total dose, dose rate, radiation quality and age at exposure. Thus, safe limits for low dose occupational irradiation are currently based on data obtained with doses far exceeding the levels expected for the general population and health risks have been largely extrapolated using the linear-nonthreshold dose-response model. The overall working hypothesis of the present study is that priming with low dose, low-linear energy transfer (LET) radiation can ameliorate the response to acute high-dose radiation exposure. We also propose that the efficacy of low-dose induced protection will be dependent upon the form and regimen of the high-dose exposure: photons versus protons versus simulated solar particle event protons (sSPE). The emphasis has been on gene expression and function of CD4+ T helper (Th) lymphocytes harvested from spleens of whole-body irradiated C57BL/6 mice, a strain that provides the genetic background for many genetically engineered strains. Evaluations of the responses of other selected cells, tissues such as skin, and organs such as lung, liver and brain were also initiated (partially funded by other sources). The long-term goal is to provide information

  10. Radiation Risks and Mitigation in Electronic Systems

    Todd, B

    2015-01-01

    Electrical and electronic systems can be disturbed by radiation-induced effects. In some cases, radiation-induced effects are of a low probability and can be ignored; however, radiation effects must be considered when designing systems that have a high mean time to failure requirement, an impact on protection, and/or higher exposure to radiat ion. High-energy physics power systems suffer from a combination of these effects: a high mean time to failure is required, failure can impact on protection, and the proximity of systems to accelerators increases the likelihood of radiation-induced events. This paper presents the principal radiation-induced effects, and radiation environments typical to high-energy physics. It outlines a procedure for designing and validating radiation-tolerant systems using commercial off-the-shelf components. The paper ends with a worked example of radiation-tolerant power converter controls that are being developed for the Large Hadron Collider and High Luminosity-Large Hadron Colli...