WorldWideScience

Sample records for balancing radiation risks

  1. Balancing Risk

    DEFF Research Database (Denmark)

    Nygaard, Lene; Rossen, Camilla Blach; Buus, Niels

    2015-01-01

    This study explored how eight pregnant women diagnosed with depression managed the decision whether or not to take antidepressants during pregnancy. In total, 11 interviews were conducted and analysed by means of constructivist grounded theory. The major category constructed was Balancing risk......, with two minor categories: Assessing depression and antidepressants and Evaluating the impact of significant others. The participants tried to make the safest decision, taking all aspects of their life into consideration. They described successful decision-making in the context of managing social norms...

  2. Balancing radiation risks and benefits of cardiac imaging: challenges for developed countries

    International Nuclear Information System (INIS)

    Full text: Cardiovascular disease remains the leading cause of death in the US, EU, Canada, Australia, and New Zealand, although coronary disease mortality has decreased due to improvements in prevention, diagnosis, and treatment. In many developed countries, most cardiologists now perform procedures involving radiopharmaceuticals, CT, or fluoroscopy. Their increased utilization, while contributing to improved care for patients with known or suspected heart disease, has been accompanied by a sharp increase in collective doses from medical radiation. E.g., an estimated ∼ 10% (∼ 0.6 mSv/person/y) of the collective dose to the US population is now attributed to nuclear stress tests. Radiation risk from any modality is highly dependent on patient age and gender. Cardiologists, like most non-radiologists, have had limited training in the safe use of radiation and are generally unaware of such facts. While one encouraging sign has been the development of appropriateness criteria for various cardiac imaging modalities, much work remains to advance radiological protection for the tens of millions of patients each year who receive cardiac imaging studies. Here we address current efforts to balance benefits of cardiac imaging with radiation risks, dose-reduction strategies, and future desiderata. General themes are improvements in technology, education, clinical standards, and reimbursement policies for these examinations. The vast majority of nuclear cardiology studies are performed using SPECT, and the radiopharmaceuticals used most widely are 99mTc sestamibi and tetrofosmin, and 201Tl. Effective doses are considerably higher for standard injected activities of 201Tl than for 99mTc agents, and the highest doses, ∼ 24 mSv, are associated with dual isotope (rest 201Tl, stress 99mTc) protocols. E.g., in the US, 1/4 of nuclear stress tests are still performed using dual isotope protocols, a practice fostered by current structuring of reimbursement. Although most stress

  3. Balancing radiation benefits and risks: The needs of an informed public

    International Nuclear Information System (INIS)

    The American public's perceptions regarding ionizing radiation do not always conform to or correlate with scientific evidence. The ultimate purpose of this coordinated Federal effort and report is to increase the public's knowledge of the benefits and risks associated with ionizing radiation. This report is divided into five sections. The first section, Introduction, discusses the public's knowledge of radiation, their perceptions of benefits versus risks, and the Federal government's role in public education. The section also outlines the charge to the Subpanel. Radiation Issues and Public Reactions discusses several radiation issues important to Federal agencies for which public education programs need to be established or enhanced. Federal Programs describes Federal agencies with public education programs on radiation and the nature of the programs they support. Education Issues and Federal Strategies explores the elements identified by the Subpanel as critical to the development and implementation of an effective Federal program in the area of public education on radiation issues and nuclear technologies. An important issue repeatedly brought up during the public sector presentations to the Subpanel was the perceived lack of Federal credibility on radiation issues in the eyes of the public. To some degree, this concern was factored into all of the recommendations developed by the subpanel. The issues discussed in this section include the fragmented nature of Federal radiation programs and the need to improve credibility, promote agency responsiveness, and support the enhancement of scientific literacy. Finally, under Recommendations, the Subpanel discusses its overall findings and conclusions

  4. Balancing radiation benefits and risks: The needs of an informed public

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    The American public`s perceptions regarding ionizing radiation do not always conform to or correlate with scientific evidence. The ultimate purpose of this coordinated Federal effort and report is to increase the public`s knowledge of the benefits and risks associated with ionizing radiation. This report is divided into five sections. The first section, Introduction, discusses the public`s knowledge of radiation, their perceptions of benefits versus risks, and the Federal government`s role in public education. The section also outlines the charge to the Subpanel. Radiation Issues and Public Reactions discusses several radiation issues important to Federal agencies for which public education programs need to be established or enhanced. Federal Programs describes Federal agencies with public education programs on radiation and the nature of the programs they support. Education Issues and Federal Strategies explores the elements identified by the Subpanel as critical to the development and implementation of an effective Federal program in the area of public education on radiation issues and nuclear technologies. An important issue repeatedly brought up during the public sector presentations to the Subpanel was the perceived lack of Federal credibility on radiation issues in the eyes of the public. To some degree, this concern was factored into all of the recommendations developed by the subpanel. The issues discussed in this section include the fragmented nature of Federal radiation programs and the need to improve credibility, promote agency responsiveness, and support the enhancement of scientific literacy. Finally, under Recommendations, the Subpanel discusses its overall findings and conclusions.

  5. Risk, Balanced Skills and Entrepreneurship

    NARCIS (Netherlands)

    C. Hsieh; S.C. Parker; M.C. van Praag

    2015-01-01

    This paper proposes that risk aversion encourages individuals to invest in balanced skill profiles, making them more likely to become entrepreneurs. By not having taken this possible linkage into account, previous research has underestimated the impacts both of risk aversion and balanced skills on t

  6. Risk, Balanced Skills and Entrepreneurship

    OpenAIRE

    Hsieh, C.; Parker, S.C.; Praag, van, B.

    2011-01-01

    This paper proposes that risk aversion encourages individuals to invest in balanced skill profiles, making them more likely to become entrepreneurs. By not having taken this possible linkage into account, previous research has underestimated the impacts both of risk aversion and balanced skills on the likelihood individuals choose entrepreneurship. Data on Dutch university graduates provides evidence which supports this contention. It thereby raises the possibility that even risk-averse peopl...

  7. Risks Associated with Ionizing Radiations

    International Nuclear Information System (INIS)

    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.

  8. Radiation balances and the solar constant

    Science.gov (United States)

    Crommelynck, D.

    1981-01-01

    The radiometric concepts are defined in order to consider various types of radiation balances and relate them to the diabetic form of the energy balance. Variability in space and time of the components of the radiation field are presented. A specific concept for sweeping which is tailored to the requirements is proposed. Finally, after establishing the truncated character of the present knowledge of the radiation balance. The results of the last observations of the solar constant are given. Ground and satellite measurement techniques are discussed.

  9. Radiation risk in nuclear medicine.

    Science.gov (United States)

    Adelstein, S James

    2014-05-01

    Given the central roles that anatomical and functional imaging now play in medical practice, there have been concerns about the increasing levels of radiation exposure and their potential hazards. Despite incomplete quantitative knowledge of the risks, it is prudent to think of radiation, even at low doses, as a potential, albeit weak, carcinogen. Thus, we are obliged to minimize its dose and optimize its benefits. Hopefully, time will clarify our estimates of the dangers. Until then, we should educate and assure our patients, their families, and colleagues that the risks have been taken into account and are well balanced by the benefits.

  10. Radiation risk estimation models.

    OpenAIRE

    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.

  11. Radiation balance of soybeans grown in Brazil

    International Nuclear Information System (INIS)

    This paper describes an experimental study of the radiation balance over a growing soybean (Glycine max (L.) Merrill) crop at a tropical agricultural experimental station, Jaboticabal (22°15′S 48°18′W), São Paulo, Brazil. Incoming shortwave radiation, S, net radiation, R, and the shortwave reflection coefficient, α, were measured over this crop from November 1976 to April 1977, and net longwave radiation, L, was deduced from the radiation balance equation. Hourly variation of the radiation components, S, αS, R and L, are presented for 4 nearly clear sky-days during the different growing crop periods. The diurnal variation of α is also presented for these 4 days. The mean daily albedo values for this vegetative surface were between 0.12 and 0.26, and inversely related to the vegetation height. A regression analysis of the radiation balance equation has been made, and the heating coefficient, β, and the longwave exchange coefficient, λ, obtained. The results of the study indicate that both β and λ are found to be descriptively helpful parameters in agricultural meteorology. Predicted regression equations for net radiation from shortwave radiation are presented for the different periods

  12. Mammography and radiation risk

    International Nuclear Information System (INIS)

    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.)

  13. Perception of radiation risks

    International Nuclear Information System (INIS)

    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

  14. Space Radiation Risk Assessment

    Science.gov (United States)

    Blakely, E.

    Evaluation of potential health effects from radiation exposure during and after deep space travel is important for the future of manned missions To date manned missions have been limited to near-Earth orbits with the moon our farthest distance from earth Historical space radiation career exposures for astronauts from all NASA Missions show that early missions involved total exposures of less than about 20 mSv With the advent of Skylab and Mir total career exposure levels increased to a maximum of nearly 200 mSv Missions in deep space with the requisite longer duration of the missions planned may pose greater risks due to the increased potential for exposure to complex radiation fields comprised of a broad range of radiation types and energies from cosmic and unpredictable solar sources The first steps in the evaluation of risks are underway with bio- and physical-dosimetric measurements on both commercial flight personnel and international space crews who have experience on near-earth orbits and the necessary theoretical modeling of particle-track traversal per cell including the contributing effects of delta-rays in particle exposures An assumption for biologic effects due to exposure of radiation in deep space is that they differ quantitatively and qualitatively from that on earth The dose deposition and density pattern of heavy charged particles are very different from those of sparsely ionizing radiation The potential risks resulting from exposure to radiation in deep space are cancer non-cancer and genetic effects Radiation from

  15. Space Radiation Cancer Risks

    Science.gov (United States)

    Cucinotta, Francis A.

    2007-01-01

    Space radiation presents major challenges to astronauts on the International Space Station and for future missions to the Earth s moon or Mars. Methods used to project risks on Earth need to be modified because of the large uncertainties in projecting cancer risks from space radiation, and thus impact safety factors. We describe NASA s unique approach to radiation safety that applies uncertainty based criteria within the occupational health program for astronauts: The two terrestrial criteria of a point estimate of maximum acceptable level of risk and application of the principle of As Low As Reasonably Achievable (ALARA) are supplemented by a third requirement that protects against risk projection uncertainties using the upper 95% confidence level (CL) in the radiation cancer projection model. NASA s acceptable level of risk for ISS and their new lunar program have been set at the point-estimate of a 3-percent risk of exposure induced death (REID). Tissue-averaged organ dose-equivalents are combined with age at exposure and gender-dependent risk coefficients to project the cumulative occupational radiation risks incurred by astronauts. The 95% CL criteria in practice is a stronger criterion than ALARA, but not an absolute cut-off as is applied to a point projection of a 3% REID. We describe the most recent astronaut dose limits, and present a historical review of astronaut organ doses estimates from the Mercury through the current ISS program, and future projections for lunar and Mars missions. NASA s 95% CL criteria is linked to a vibrant ground based radiobiology program investigating the radiobiology of high-energy protons and heavy ions. The near-term goal of research is new knowledge leading to the reduction of uncertainties in projection models. Risk projections involve a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. The current model for projecting space radiation

  16. Radiation risk estimation

    International Nuclear Information System (INIS)

    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

  17. The Risk Management Balancing Act

    OpenAIRE

    International Finance Corporation

    2011-01-01

    The purpose of the report is to present the findings from IFC’s recent survey on risk and nonperforming loan management practices in financial institutions together with supporting benchmarks and global trends in risk management. Top tier financial institutions in their respective markets have participated in the survey, including 25 SME focused banks and 2 microfinance institutions in 18 countries (see Exhibit 1). The emphasis on credit risk in this report stems from credit...

  18. Radiation force and balance of electromagnetic momentum

    Science.gov (United States)

    Campos, I.; Jiménez, J. L.; Roa-Neri, J. A. E.

    2016-07-01

    Some force densities can be expressed as a divergence of a stress tensor, as is the case with the electromagnetic force density. We have shown elsewhere that from the Maxwell equations several balance equations of electromagnetic momentum can be derived, depending on the form these equations are expressed in terms of fields E, D, B, H, and polarisations P and M. These balance equations imply different force densities and different stress tensors, providing a great flexibility to solve particular problems. Among these force densities we have found some proposed in the past with plausibility arguments, like the Einstein-Laub force density, while other proposed force densities appear as particular or limit cases of these general force densities, like the Helmholtz force density. We calculate the radiation force of an electromagnetic wave incident on a semi-infinite negligibly absorbing material using these balance equations, corroborating in this way that the surface integration of the stress tensor gives the same result that the calculation made through a volume integration of the force density, as done by Bohren. As is usual in applications of Gauss’s theorem, the surface on which the surface integral is to be performed must be chosen judiciously, and due care of discontinuities on the boundary conditions must be taken. Advanced undergraduates and graduate students will find a different approach to new aspects of the interaction of radiation with matter.

  19. RISK BALANCING IN AN INTEGRATED FARM RISK MANAGEMENT PLAN

    OpenAIRE

    Escalante, Cesar L.; Barry, Peter J.

    2001-01-01

    Using optimization techniques in a simulation framework, this study demonstrates the synergy between risk balancing and alternative strategies in effectively reducing risk under changing farm conditions. Highly risk-averse farmers tend to prefer integrated risk-management plans, based on the diversification principle, that yield offsetting combinations of the risk-reducing benefits of most strategies and the profit-generating capacities of the others. The greater appeal of a more diversified ...

  20. Risk Factors: Radiation

    Science.gov (United States)

    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.

  1. Risk assessment perspectives in radiation protection

    International Nuclear Information System (INIS)

    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.)

  2. Ionizing radiation: benefits vs. risks

    International Nuclear Information System (INIS)

    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

  3. Theoretical analysis of radiation-balanced double clad fiber laser

    Institute of Scientific and Technical Information of China (English)

    CHEN Ji-xin; SUI Zhan; CHEN Fu-shen; LI Ming-zhong; WANG Jian-jun

    2005-01-01

    In this letter,a theoretical model of radiation-balanced double clad fiber laser is presented.The characteristic of the laser with Yb doped double clad fiber is analyzed numerically.It is concluded that high output laser power can be obtained by selecting output coupling mirror with lower reflectivity,improving Yb doped concentration and choosing fiber length. This result can help us to design radiation balanced fiber laser.

  4. Radiation balance in the sweet sorghum crop

    International Nuclear Information System (INIS)

    The fluxes of incident solar radiation, reflected and net radiation were measured during the growing cicle of two fields of sweet sorghum (Sorghum bicolor L.), cus. BR-501 and BR-503, maintained under convenient irrigation level. Resultant data allowed to estimate the crop albedo as well as the estimates of Rn. (M.A.C.)

  5. Sarcoma risk after radiation exposure

    Directory of Open Access Journals (Sweden)

    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 (

  6. Influence of soybean pubescence type on radiation balance

    International Nuclear Information System (INIS)

    Increasing the density of pubescence on the leaves and stems of soybeans (Glycine max L.) should influence the radiation balance of the soybean canopy and affect the evapotranspiration and photosynthetic rates. This study was undertaken to evaluate the influence of increased pubescence density on various components of the radiation balance. Near-isogenic lines of two soybean cultivars (Clark and Harosoy) were grown in four adjacent small plots (18 m · 18 m) during the 1980, 1981, and 1982 growing seasons near Mead, Nebr. The soil at this site is classified as a Typic Argiudoll. The isolines of each cultivar varied only in the amount of pubescence (dense vs. normal pubescence). Measurements of albedo, reflected photosynthetically active radiation (PAR), emitted longwave radiation, and net radiation were made over the crop surfaces with instruments mounted on a rotating boom located at the intersection of the four plots. Radiative canopy temperatures were measured with a handheld infrared thermometer (IRT). Results show that dense pubescence increased reflection of shortwave radiation and PAR by 3 to 5% and 8 to 11%, respectively. Emitted longwave radiation and radiative canopy temperature were not significantly affected by increased pubescence, although there was a slight tendency for the dense pubescent canopy to be cooler. Increased pubescence decreased net radiation over the canopy by 0.5 to 1.5%. These results suggest that soybeans with dense pubescence may be slightly better adapted to the high radiation, high temperature, and limited moisture conditions of the eastern Great Plains than are those with normal pubescence

  7. Evaluation of surface energy and radiation balance systems for FIFE

    Science.gov (United States)

    Fritschen, Leo J.; Qian, Ping

    1988-01-01

    The energy balance and radiation balance components were determined at six sites during the First International Satellite Land Surface Climatology Project Field Experiment (FIFE) conducted south of Manhattan, Kansas during the summer of 1987. The objectives were: to determine the effect of slope and aspect, throughout a growing season, on the magnitude of the surface energy balance fluxes as determined by the Energy Balance Method (EBM); to investigate the calculation of the soil heat flux density at the surface as calculated from the heat capacity and the thermal conductivity equations; and to evaluate the performance of the Surface Energy and Radiation Balance System (SERBS). A total of 17 variables were monitored at each site. They included net, solar (up and down), total hemispherical (up and down), and diffuse radiation, soil temperature and heat flux density, air and wet bulb temperature gradients, wind speed and direction, and precipitation. A preliminary analysis of the data, for the season, indicate that variables including net radiation, air temperature, vapor pressure, and wind speed were quite similar at the sites even though the sites were as much as 16 km apart and represented four cardinal slopes and the top of a ridge.

  8. Canopy radiation transmission for an energy balance snowmelt model

    Science.gov (United States)

    Mahat, Vinod; Tarboton, David G.

    2012-01-01

    To better estimate the radiation energy within and beneath the forest canopy for energy balance snowmelt models, a two stream radiation transfer model that explicitly accounts for canopy scattering, absorption and reflection was developed. Upward and downward radiation streams represented by two differential equations using a single path assumption were solved analytically to approximate the radiation transmitted through or reflected by the canopy with multiple scattering. This approximation results in an exponential decrease of radiation intensity with canopy depth, similar to Beer's law for a deep canopy. The solution for a finite canopy is obtained by applying recursive superposition of this two stream single path deep canopy solution. This solution enhances capability for modeling energy balance processes of the snowpack in forested environments, which is important when quantifying the sensitivity of hydrologic response to input changes using physically based modeling. The radiation model was included in a distributed energy balance snowmelt model and results compared with observations made in three different vegetation classes (open, coniferous forest, deciduous forest) at a forest study area in the Rocky Mountains in Utah, USA. The model was able to capture the sensitivity of beneath canopy net radiation and snowmelt to vegetation class consistent with observations and achieve satisfactory predictions of snowmelt from forested areas from parsimonious practically available information. The model is simple enough to be applied in a spatially distributed way, but still relatively rigorously and explicitly represent variability in canopy properties in the simulation of snowmelt over a watershed.

  9. Breast carcinogenesis: risk of radiation

    International Nuclear Information System (INIS)

    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

  10. Radiation risks and radiation protection at CRNL

    International Nuclear Information System (INIS)

    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

  11. Including "evidentiary balance" in news media coverage of vaccine risk.

    Science.gov (United States)

    Clarke, Christopher E; Dixon, Graham N; Holton, Avery; McKeever, Brooke Weberling

    2015-01-01

    Journalists communicating risk-related uncertainty must accurately convey scientific evidence supporting particular conclusions. Scholars have explored how "balanced" coverage of opposing risk claims shapes uncertainty judgments. In situations where a preponderance of evidence points to a particular conclusion, balanced coverage reduces confidence in such a consensus and heightens uncertainty about whether a risk exists. Using the autism-vaccine controversy as a case study, we describe how journalists can cover multiple sides of an issue and provide insight into where the strength of evidence lies by focusing on "evidentiary balance." Our results suggest that evidentiary balance shapes perceived certainty that vaccines are safe, effective, and not linked to autism through the mediating role of a perception that scientists are divided about whether a link exists. Deference toward science, moreover, moderates these relationships under certain conditions. We discuss implications for journalism practice and risk communication. PMID:25010352

  12. Ionization radiations - basis, risks and benefits

    International Nuclear Information System (INIS)

    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)

  13. Radiation teratogenesis: fetal risk and abortion

    International Nuclear Information System (INIS)

    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

  14. Farm household risk balancing: empirical evidence from Switzerland

    NARCIS (Netherlands)

    Mey, de Yann; Wauters, E.; Schmid, D.; Passel, van S.; Vancauteren, Mark; Lips, M.

    2016-01-01

    This paper presents the first empirical evidence on household risk balancing behavior, i.e., strategic off-farm decisions in response to changes in expected business risk. Using Swiss FADN data, we estimate a fixed effects seemingly unrelated regression model to analyze how farm households jointly a

  15. Managing industrial price risk: a balancing act

    Energy Technology Data Exchange (ETDEWEB)

    Muse, J-F. [Cargill Energy (United States)

    2000-07-01

    The challenge of managing industrial price risk is assessed by a senior executive of Cargill, a diversified industrial conglomerate, involved in steel manufacturing and recycling, oilseeds, cocoa, beef, pork, and poultry processing, fertilizer and fruit juice production, in addition to trading and financial risk management. Energy is a key component in many of Cargill's businesses, hence the company has good reason to be concerned about price volatility. The effects of energy risk management on the company's shareholders are demonstrated by an analysis of month-to-month price fluctuations over the Nov 1999 to Oct 2000 period, showing the monthly value of risk at the 95 per cent confidence level as $4,832,195. The effects of alternatives for an end-user such as passing on cost to customers, improving energy efficiency. fuel switching and production curtailment, are explored and limitations and problems with each of the approaches are discussed. The best options for industrial end-users of natural gas are suggested to be a proactive risk management program in the short-term and asset diversification, fuel switching, and geographic relocation of production facilities in the long-term.

  16. SGLT2 Inhibitors: Benefit/Risk Balance.

    Science.gov (United States)

    Scheen, André J

    2016-10-01

    Inhibitors of sodium-glucose cotransporters type 2 (SGLT2) reduce hyperglycemia by increasing urinary glucose excretion. They have been evaluated in patients with type 2 diabetes treated with diet/exercise, metformin, dual oral therapy or insulin. Three agents are available in Europe and the USA (canagliflozin, dapagliflozin, empagliflozin) and others are commercialized in Japan or in clinical development. SGLT2 inhibitors reduce glycated hemoglobin, with a minimal risk of hypoglycemia. They exert favorable effects beyond glucose control with consistent body weight, blood pressure, and serum uric acid reductions. Empagliflozin showed remarkable reductions in cardiovascular/all-cause mortality and in hospitalization for heart failure in patients with previous cardiovascular disease. Positive renal outcomes were also shown with empagliflozin. Mostly reported adverse events are genital mycotic infections, while urinary tract infections and events linked to volume depletion are rather rare. Concern about a risk of ketoacidosis and bone fractures has been recently raised, which deserves caution and further evaluation.

  17. Practical risk management in radiation therapy

    International Nuclear Information System (INIS)

    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)

  18. Cancellation of coherent synchrotron radiation kicks with optics balance.

    Science.gov (United States)

    Di Mitri, S; Cornacchia, M; Spampinati, S

    2013-01-01

    Minimizing transverse emittance is essential in linear accelerators designed to deliver very high brightness electron beams. Emission of coherent synchrotron radiation (CSR), as a contributing factor to emittance degradation, is an important phenomenon to this respect. A manner in which to cancel this perturbation by imposing certain symmetric conditions on the electron transport system has been suggested.We first expand on this idea by quantitatively relating the beam Courant-Snyder parameters to the emittance growth and by providing a general scheme of CSR suppression with asymmetric optics, provided it is properly balanced along the line. We present the first experimental evidence of this cancellation with the resultant optics balance of multiple CSR kicks: the transverse emittance of a 500 pC, sub-picosecond, high brightness electron beam is being preserved after the passage through the achromatic transfer line of the FERMI@Elettra free electron laser, and emittance growth is observed when the optics balance is intentionally broken. We finally show the agreement between the theoretical model and the experimental results. This study holds the promise of compact dispersive lines with relatively large bending angles, thus reducing costs for future electron facilities.

  19. Risk and benefits in ionizing radiation uses

    International Nuclear Information System (INIS)

    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.

  20. Space radiation and cardiovascular disease risk.

    Science.gov (United States)

    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

  1. Space radiation and cardiovascular disease risk.

    Science.gov (United States)

    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.

  2. Delineating organs at risk in radiation therapy

    CERN Document Server

    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

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

    Science.gov (United States)

    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

  4. Epidemiological data and radiation risk estimates

    International Nuclear Information System (INIS)

    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)

  5. [Epidemiological data and radiation risk estimates].

    Science.gov (United States)

    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

  6. Radiation exposure and radiation risk of the population

    International Nuclear Information System (INIS)

    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)

  7. Quantitative risk in radiation protection standards

    International Nuclear Information System (INIS)

    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.)

  8. Space Radiation and Risks to Human Health

    Science.gov (United States)

    Huff, Janice L.

    2014-01-01

    The radiation environment in space poses significant challenges to human health and is a major concern for long duration manned space missions. Outside the Earth's protective magnetosphere, astronauts are exposed to higher levels of galactic cosmic rays, whose physical characteristics are distinct from terrestrial sources of radiation such as x-rays and gamma-rays. Galactic cosmic rays consist of high energy and high mass nuclei as well as high energy protons; they impart unique biological damage as they traverse through tissue with impacts on human health that are largely unknown. The major health issues of concern are the risks of radiation carcinogenesis, acute and late decrements to the central nervous system, degenerative tissue effects such as cardiovascular disease, as well as possible acute radiation syndromes due to an unshielded exposure to a large solar particle event. The NASA Human Research Program's Space Radiation Program Element is focused on characterization and mitigation of these space radiation health risks along with understanding these risks in context of the other biological stressors found in the space environment. In this overview, we will provide a description of these health risks and the Element's research strategies to understand and mitigate these risks.

  9. Risks associated with radiation: General information

    International Nuclear Information System (INIS)

    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

  10. Radiation risks in the workplace in perspective

    International Nuclear Information System (INIS)

    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)

  11. Radiation risks for patient and personnel

    International Nuclear Information System (INIS)

    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)

  12. Radiation protection and risk assessment

    International Nuclear Information System (INIS)

    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)

  13. Radiation and risk in physics education

    International Nuclear Information System (INIS)

    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

  14. Evaluation of surface energy and radiation balance systems on the Konza Prairie

    Science.gov (United States)

    Fritschen, Leo J.

    1987-01-01

    Four Surface Energy and Radiation Balance Systems (SERBS) were installed and operated for two weeks in Kansas during July of 1986. Surface energy and radiation balances were investigated on six sites on the Konza Prairie about 3 km south of Manhattan, Kansas. Measurements were made to allow the computation of these radiation components: total solar and diffuse radiation, reflected solar radiation, net radiation, and longwave radiation upward and downward. Measurements were made to allow the computation of the sensible and latent heat fluxes by the Bowen ratio method using differential psychrometers on automatic exchange mechanisms. The report includes a description of the experimental sites, data acquisition systems and sensors, data acquisitions system operating instructions, and software used for data acquisition and analysis. In addition, data listings and plots of the energy balance components for all days and systems are given.

  15. Radiation risk during long-term spaceflight

    Science.gov (United States)

    Petrov, V. M.

    Cosmonauts` exposure to cosmic rays during long-term spaceflight can cause unfavorable effects in health and risk for the crew members` lives. All unfavorable effects induced by exposure should be taken into consideration for the risk estimation. They should include both the acute deterministic effects and delayed effects called stochastic. On the ground the limitation of unfavorable consequences of acute exposure is achieved by means of establishing dose limits. But in space applications this approach can't be acceptable. Establishing a fixed dose limit is adequate to introducing indefinite reserve coefficient and therefore ineffective usage of spacecraft resource. The method of radiation risk calculation caused by acute and delayed effects of cosmonauts' exposure is discussed and substantiated in the report. Peculiarities of the impact of permanent radiation sources (galactic cosmic rays and trapped radiation) and the variable one (solar cosmic rays) are taken into consideration.

  16. Ionizing Radiation Environments and Exposure Risks

    Science.gov (United States)

    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.

  17. Evidence Report: Risk of Radiation Carcinogenesis

    Science.gov (United States)

    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).

  18. Health risks associated with environmental radiation exposures

    International Nuclear Information System (INIS)

    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)

  19. Radiation risk due to occupational exposure

    International Nuclear Information System (INIS)

    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)

  20. Radiation risks and benefits: politics and morality

    International Nuclear Information System (INIS)

    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

  1. Comparison of radiation and chemical risks

    International Nuclear Information System (INIS)

    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)

  2. Emerging Radiation Health-Risk Mitigation Technologies

    Science.gov (United States)

    Wilson, J. W.; Cucinotta, F. A.; Schimmerling, W.

    2004-02-01

    Past space missions beyond the confines of the Earth's protective magnetic field have been of short duration and protection from the effects of solar particle events was of primary concern. The extension of operational infrastructure beyond low-Earth orbit to enable routine access to more interesting regions of space will require protection from the hazards of the accumulated exposures of Galactic Cosmic Rays (GCR). There are significant challenges in providing protection from the long-duration exposure to GCR: the human risks to the exposures are highly uncertain and safety requirements places unreasonable demands in supplying sufficient shielding materials in the design. A vigorous approach to future radiation health-risk mitigation requires a triage of techniques (using biological and technical factors) and reduction of the uncertainty in radiation risk models. The present paper discusses the triage of factors for risk mitigation with associated materials issues and engineering design methods.

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

    International Nuclear Information System (INIS)

    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

  4. Radiation Risk Projections for Space Travel

    Science.gov (United States)

    Cucinotta, Francis

    2003-01-01

    Space travelers are exposed to solar and galactic cosmic rays comprised of protons and heavy ions moving with velocities close to the speed of light. Cosmic ray heavy ions are known to produce more severe types of biomolecular damage in comparison to terrestrial forms of radiation, however the relationship between such damage and disease has not been fully elucidated. On Earth, we are protected from cosmic rays by atmospheric and magnetic shielding, and only the remnants of cosmic rays in the form of ground level muons and other secondary radiations are present. Because human epidemiology data is lacking for cosmic rays, risk projection must rely on theoretical understanding and data from experimental models exposed to space radiation using charged particle accelerators to simulate space radiation. Although the risks of cancer and other late effects from cosmic rays are currently believed to present a severe challenge to space travel, this challenge is centered on our lack of confidence in risk projections methodologies. We review biophysics and radiobiology data on the effects of the cosmic ray heavy ions, and the current methods used to project radiation risks . Cancer risk projections are described as a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Risk projections for space travel are described using Monte-Carlo sampling from subjective error di stributions that represent the lack of knowledge in each factor that contributes to the projection model in order to quantify the overall uncertainty in risk projections. This analysis is applied to space mi ssion scenarios including lunar colony, deep space outpost, and a Mars mission. Results suggest that the number of days in space where cancer mortality risks can be assured at a 95% confidence level to be below the maximum acceptable risk for radi ation workers on Earth or the International Space Station is only on the order

  5. Radiation induced cancer risk, detriment and radiation protection

    International Nuclear Information System (INIS)

    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)

  6. The variability of radiative balance elements and air temperature on the Asian region of Russia

    Directory of Open Access Journals (Sweden)

    E. V. Kharyutkina

    2011-05-01

    Full Text Available The variability of spatial-temporal distribution of temperature and radiative and heat balances components is investigated for the Asian territory of Russia (45–80° N, 60–180° E using JRA-25, NCEP/DOE AMIP reanalysis data and observational data for the period of current global warming 1979–2008. It is shown that since the beginning of 90s of XX century the increase of back earth-atmosphere short-wave radiation is observed. Such tendency is in conformity with the cloud cover dynamics and downward short-wave radiation at the surface. Annual averaged radiative balance values at the top are negative; it is consistent with negative annual averaged air temperature, averaged over territory. The downward trend of radiative balance is the most obvious after the beginning of 90s of XX century.

  7. Environmental radiation standards and risk limitation

    International Nuclear Information System (INIS)

    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

  8. On ionising radiation and breast cancer risk

    International Nuclear Information System (INIS)

    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

  9. On ionising radiation and breast cancer risk

    Energy Technology Data Exchange (ETDEWEB)

    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

  10. BALANCE

    Science.gov (United States)

    Carmichael, H.

    1953-01-01

    A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

  11. Invited commentary: a fine balance--weighing risk factors against risk.

    Science.gov (United States)

    Walsh, Michael G

    2009-01-15

    Fracture is a leading cause of disability in the aging population. Because the cost of fracture in terms of medical expenditures and quality of life lost can be substantial, it is essential to identify a complete profile of fracture risk for the development of timely interventions. Risk factors for fracture have most often been identified clinically. Thus, the contribution by Wagner et al. in this issue of the Journal is particularly important, since it demonstrates a robust association between balance impairment and fracture in a population-based setting. It is unclear, however, whether isolating balance as a risk factor can tell us enough about the clustering of risk factors for fracture that accompanies frailty. Indeed, this problem of risk clustering is one that epidemiologists often encounter as we try to locate the mediating processes between exposures and outcomes that lead downstream through complex interacting causal pathways. In this commentary, the author discusses the importance, particularly when studying frailty and fracture, of quantifying risk clustering rather than continuing to rely on solitary risk factors. Moreover, the author suggests the use of Bayesian networks in the expansion of our tool kit in this field of research. PMID:19064647

  12. Investigation of the Impacts of Measured and Calculated Radiation Balance Components on Evapotranspiration

    Science.gov (United States)

    Akataş, Nilcan; Yeşilköy, Serhan; Şaylan, Levent

    2016-04-01

    Determination of surface energy balance over agricultural lands plays a crucial role to better investigation of sustainable agriculture and food security which are related to evapotranspiration. Surface energy balance components that include net shortwave and longwave radiation depend on surface conditions like surface albedo and climate of a region. Surface albedo is ratio between reflected longwave radiation and incoming shortwave radiation. There are many different crops in agriculture ecosystem. Thus, surface energy balance components vary by vegetation surfaces. Net radiation is most important component of surface energy balance which is difference between net shortwave and longwave radiation. These are calculated by commonly used equations and applied to the FAO Penman& Monteith equation using meteorological stations' data located in cities. However, there are differences between urban areas and agricultural ecosystems. This situation causes to the calculation errors. In this research, it is aimed to investigate the changes between estimated and measured surface energy balance components which are estimated by meteorological stations' data in the urban area and measurements from an rural area over winter wheat surface 2014-2015 growing season in Thrace Region located in the Northwestern part of Turkey, Kırklareli city. Keywords: Surface energy balance, winter wheat, FAO Penman-Monteith, Kırklareli/Turkey

  13. Radiation Risk and the Mission to Mars

    Science.gov (United States)

    Durante, Marco

    2014-06-01

    Space radiation represents a major showstopper for human space exploration. While solar particle events and trapped protons can be effectively shielded, high-energy nuclei in the galactic cosmic radiation have a high biological effectiveness and cannot be shielded with the limited mass available on a spacecraft. A mission to Mars has been recently proposed (Inspiration Mars), consisting of a flyby with a crew of two astronauts starting in 2018 and lasting 501 days. Based on the recent measurements of the galactic cosmic ray dose on the Mars Science Laboratory and on the most recent update on the risk coefficients from the Atomic bomb survivors, it can be shown that the mission to Mars with current technology may expose the crew to a significant cancer risk.

  14. Hedgehog signaling and radiation induced liver injury: a delicate balance.

    Science.gov (United States)

    Kabarriti, Rafi; Guha, Chandan

    2014-07-01

    Radiation-induced liver disease (RILD) is a major limitation of radiation therapy (RT) for the treatment of liver cancer. Emerging data indicate that hedgehog (Hh) signaling plays a central role in liver fibrosis and regeneration after liver injury. Here, we review the potential role of Hh signaling in RILD and propose the temporary use of Hh inhibition during liver RT to radiosensitize HCC tumor cells and inhibit their progression, while blocking the initiation of the radiation-induced fibrotic response in the surrounding normal liver. PMID:26202634

  15. Energy and radiation balance components for three grass surfaces near Kursk, Russia

    Science.gov (United States)

    Fritschen, Leo J.

    1992-01-01

    The energy and radiation balance components were determined over three grass surfaces, located on the Streletskaya steppe during July 1991. The Bowen ratio energy balance method was used to determine the sensible and latent heat flux densities using six computer controlled systems. A total of 126 variables were sampled, including global, diffuse, and reflected solar radiation, long wave radiation (up and down), net radiation, photosynthetically active radiation above and below the vegetation, infrared surface temperatues, soil temperature and heat flow, air temperature and vapor pressure at two levels, wind speed and direction, and precipitation. The ranking of the sites from greatest to smallest for net radiation and latent heat flux density were preserve, mowed in 1990, and mowed in 1991. The ranking of the sites from greatest to smallest for sensible heat flux density were mowed in 1990, mowed in 1991, and preserve.

  16. Radiation and energy balance of lettuce culture inside a polyethylene greenhouse

    International Nuclear Information System (INIS)

    The objective of this paper was to describe the radiation and energy balance, during the lettuce (Lactuca sativa, L. cv. Verônica) crop cycle inside a polyethylene greenhouse. The radiation and energy balance was made inside a tunnel greenhouse with polyethylene cover (100 mm) and in an external area, both areas with 35 m2. Global, reflected and net radiation, soil heat flux and air temperature (dry and humid) were measured during the crop cycle. A Datalogger, which operated at 1 Hz frequency, storing 5 minutes averages was utilized. The global (K↓) and reflected (K) radiations showed that the average transmission of global radiation (K↓in / K↓ex) was almost constant, near to 79.59%, while the average ratio of reflected radiation (Kin / Kex) was 69.21% with 8.47% standard-deviation. The normalized curves of short-wave net radiation, in relation to the global radiation (K*/ K↓), found for both environments, were almost constant at the beginning of cycle; this relation decreased in the final stage of culture. The normalized relation (Rn/ K↓) was bigger in the external area, about 12%, when the green culture covered the soil surface. The long-wave radiation balance average (L*) was bigger outside, about 50%. The energy balance, estimated in terms of vertical fluxes, showed that, for the external area, in average, 83.07% of total net radiation was converted in latent heat evaporation (LE), and 18% in soil heat flux (G), and 9.96% in sensible heat (H), while inside of the greenhouse, 58.71% of total net radiation was converted in LE, 42.68% in H, and 28.79% in G. (author)

  17. Farm household risk balancing: implications for policy from an EU perspective

    NARCIS (Netherlands)

    Wauters, E.; Mey, de Yann; Winsen, van F.; Passel, van S.; Vancauteren, Mark; Lauwers, L.

    2015-01-01

    Purpose
    – Building on the risk balancing theory and on recent discussions the appropriateness of using farm income maximization as behavioural assumption, this paper extends the risk balancing framework by accounting for business-household interactions. The purpose of this paper is to theoretica

  18. Balanced economic indicators as a tool for effective management of banking risks

    Directory of Open Access Journals (Sweden)

    S.V. Andros

    2011-10-01

    Full Text Available Processed system of key performance indicators of banking activities. Characteristic of the key performance indicators of the bank as parameters in the dynamic model. Set algorithm of key performance indicators balancing to determine allowable limit values of each indicator. The necessity of a balanced system of economic indicators as an effective tool for management of banking risks. A direction of bank development strategy using balanced economic indicators in the context of banking risks.

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

    DEFF Research Database (Denmark)

    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....

  20. DNA Damage Signals and Space Radiation Risk

    Science.gov (United States)

    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.

  1. Radiation and health. Benefit and risks

    International Nuclear Information System (INIS)

    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.

  2. Influence of resonance radiation transfer on ionization balance in a positive column plasma

    Science.gov (United States)

    Golubovskii, Yu; Syasko, A.

    2016-08-01

    A method of self-consistent solution of charged particles balance equation, which is described by a differential equation of ambipolar diffusion, and an equation of resonance atom balance, which is described by an integral equation of radiation transfer, is proposed. The method is related to a replacement of an integral operator and a differential operator by a system of linear algebraic equations. The difference between a precise solution and a solution in the approximation of the effective resonance transition probability is shown. The influence of highest diffusion and radiation modes becomes apparent during transition to a contracted state.

  3. Radiation doses and risks from internal emitters

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, John [Health Protection Agency, Radiation Protection Division, CRCE, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom); Day, Philip [School of Chemistry, University of Manchester, Manchester M13 9PL (United Kingdom)], E-mail: john.harrison@hpa.org.uk, E-mail: philip.day@manchester.ac.uk

    2008-06-01

    This review updates material prepared for the UK Government Committee Examining Radiation Risks from Internal Emitters (CERRIE) and also refers to the new recommendations of the International Commission on Radiological Protection (ICRP) and other recent developments. Two conclusions from CERRIE were that ICRP should clarify and elaborate its advice on the use of its dose quantities, equivalent and effective dose, and that more attention should be paid to uncertainties in dose and risk estimates and their implications. The new ICRP recommendations provide explanations of the calculation and intended purpose of the protection quantities, but further advice on their use would be helpful. The new recommendations refer to the importance of understanding uncertainties in estimates of dose and risk, although methods for doing this are not suggested. Dose coefficients (Sv per Bq intake) for the inhalation or ingestion of radionuclides are published as reference values without uncertainty. The primary purpose of equivalent and effective dose is to enable the summation of doses from different radionuclides and from external sources for comparison with dose limits, constraints and reference levels that relate to stochastic risks of whole-body radiation exposure. Doses are calculated using defined biokinetic and dosimetric models, including reference anatomical data for the organs and tissues of the human body. Radiation weighting factors are used to adjust for the different effectiveness of different radiation types, per unit absorbed dose (Gy), in causing stochastic effects at low doses and dose rates. Tissue weighting factors are used to take account of the contribution of individual organs and tissues to overall detriment from cancer and hereditary effects, providing a simple set of rounded values chosen on the basis of age- and sex-averaged values of relative detriment. While the definition of absorbed dose has the scientific rigour required of a basic physical quantity

  4. A modified Wheeler cap method for radiation efficiency measurement of balanced electrically small antennas

    DEFF Research Database (Denmark)

    Zhang, Jiaying; Pivnenko, Sergey; Breinbjerg, Olav

    2010-01-01

    Measurement of radiation efficiency for ultra small antennas represents a great challenge due to influence of the feeding cable. The Wheeler cap method is often used to measure the radiation efficiency of small antennas. However, it is well applicable for antennas on a ground plane......, but not for balanced antennas like loops or dipoles. In this paper, a modified Wheeler cap method is proposed for the radiation efficiency measurement of balanced electrically small antennas and a three-port network model of the Wheeler cap measurement is introduced. The advantage of the modified method...... is that it is wideband, thus does not require any balun, and both the antenna input impedance and radiation efficiency can be obtained. An electrically small loop antenna and a wideband dipole were simulated and measured according to the proposed method and the results of measurements and simulations are presented...

  5. Assessing climate change. Temperatures, solar radiation, and heat balance

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Donald

    2008-07-01

    In ASSESSING CLIMATE CHANGE Donald Rapp has investigated a large body of scientific data relevant to climate change, approaching each element with necessary (but neutral) scientific skepticism. The chapters of the book attempt to answer a number of essential questions in relation to global warming and climate change. He begins by showing how the earth's climate has varied in the past, discussing ice ages, the Holocene period since the end of the last ice age, particularly during the past 1000 years. He investigates the reliability of ''proxies'' for historical temperatures and assesses the hockey stick version of global temperatures for the past millennium. To do this effectively he looks carefully at how well near surface temperatures of land and ocean on earth have been monitored during the past 100 years or more, and looks at the utility and significance of a single global average temperature. Topics such as the variability of the Sun and the Earth's heat balance are discussed in considerable detail. The author also investigates how the current global warming trend compares with past fluctuations in earth's climate and what is the likelihood that the warming trend we are experiencing now is primarily just another in a series of natural climate fluctuations as opposed to a direct result of human activities. A key factor in understanding what may happen in the future is to examine the credibility of the global climate models which claim that greenhouse gases produce most of the temperature rise of the 20th Century, and forecast much greater impacts in the century ahead. Finally, the book considers future global energy requirements, fossil fuel usage and carbon dioxide production, public policy relating to global warming, and agreements such as the Kyoto Protocol. (orig.)

  6. Balance 2003 of the risks control at the Cea

    International Nuclear Information System (INIS)

    As a research center on the energy, the information and health technologies and the defense, the Cea activities are indissociable from the risk control notion. To organize the risks management, the Cea decided to create in july 2003 a special pole of risks control and management. This presentation is based on some major topics of the risks control: the environmental impact control, the occupational risks control, the installations safety control and the hazardous matter transport control. (A.L.B.)

  7. Solid tumor risks after high doses of ionizing radiation

    OpenAIRE

    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...

  8. Understanding radiation and risk: the importance of primary and secondary education

    International Nuclear Information System (INIS)

    In Japan's primary and secondary schools, radiation and radioactivity are taught as part of the curriculum dealing with social science subjects. Students learn much about the hazardous features of radiation, but lack the scientific understanding necessary to build a more balanced picture. Although the same point applies to education covering the harmful effects of volcanic eruptions, earthquakes, electrical storms and so on, public understanding of these events is relatively high and students are generally able to make informed judgments about the risks involved. By contrast, their limited understanding of radiation often contributes to fears that it is evil or even supernatural. To correct this distortion, it is important that primary and secondary education includes a scientific explanation of radiation. Like heat and light, radiation is fundamental to the history of the universe; and scientific education programs should give appropriate emphasis to this important subject. Students would then be able to make more objective judgments about the useful and hazardous aspects of radiation. (author)

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

    International Nuclear Information System (INIS)

    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

  10. Heat balance structure during nights with radiation and advection-radiation weather in autumn for standard surface of grass in Ursynów-WAU

    International Nuclear Information System (INIS)

    Mean duration of heat balance components during autumn nights with advection-radiation and radiation weather in years 1994-99 were stated on the basis of data observed in meteorological station Ursynów-WAU. Mean fluxes of heat balance components and values of components ratios are presented in tables

  11. Are balance problems connected to reading speed or the familial risk of dyslexia?

    NARCIS (Netherlands)

    Viholainen, Helena; Aro, Mikko; Ahonen, Timo; Crawford, Susan; Cantell, Marja; Kooistra, Libbe

    2011-01-01

    AIM: The aim of this study was to examine the connection between balance problems and reading speed in children with and without a familial risk of dyslexia by controlling for the effects of attention, hyperactivity, and cognitive and motor functioning. METHOD: The prevalence of balance problems was

  12. Are Balance Problems Connected to Reading Speed or the Familial Risk of Dyslexia?

    Science.gov (United States)

    Viholainen, Helena; Aro, Mikko; Ahonen, Timo; Crawford, Susan; Cantell, Marja; Kooistra, Libbe

    2011-01-01

    Aim: The aim of this study was to examine the connection between balance problems and reading speed in children with and without a familial risk of dyslexia by controlling for the effects of attention, hyperactivity, and cognitive and motor functioning. Method: The prevalence of balance problems was studied in 94 children (48 females, 46 males)…

  13. Review of the current status of radiation risk estimates

    International Nuclear Information System (INIS)

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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.

  16. Evaluating shielding effectiveness for reducing space radiation cancer risks

    International Nuclear Information System (INIS)

    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

  17. Evaluating Shielding Effectiveness for Reducing Space Radiation Cancer Risks

    Science.gov (United States)

    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.

  18. [Use of ionizing radiation sources in metallurgy: risk assessment].

    Science.gov (United States)

    Giugni, U

    2012-01-01

    Use of ionizing radiation sources in the metallurgical industry: risk assessment. Radioactive sources and fixed or mobile X-ray equipment are used for both process and quality control. The use of ionizing radiation sources requires careful risk assessment. The text lists the characteristics of the sources and the legal requirements, and contains a description of the documentation required and the methods used for risk assessment. It describes how to estimate the doses to operators and the relevant classification criteria used for the purpose of radiation protection. Training programs must be organized in close collaboration between the radiation protection expert and the occupational physician.

  19. Influence of snow cover changes on surface radiation and heat balance based on the WRF model

    Science.gov (United States)

    Yu, Lingxue; Liu, Tingxiang; Bu, Kun; Yang, Jiuchun; Chang, Liping; Zhang, Shuwen

    2016-07-01

    The snow cover extent in mid-high latitude areas of the Northern Hemisphere has significantly declined corresponding to the global warming, especially since the 1970s. Snow-climate feedbacks play a critical role in regulating the global radiation balance and influencing surface heat flux exchange. However, the degree to which snow cover changes affect the radiation budget and energy balance on a regional scale and the difference between snow-climate and land use/cover change (LUCC)-climate feedbacks have been rarely studied. In this paper, we selected Heilongjiang Basin, where the snow cover has changed obviously, as our study area and used the WRF model to simulate the influences of snow cover changes on the surface radiation budget and heat balance. In the scenario simulation, the localized surface parameter data improved the accuracy by 10 % compared with the control group. The spatial and temporal analysis of the surface variables showed that the net surface radiation, sensible heat flux, Bowen ratio, temperature and percentage of snow cover were negatively correlated and that the ground heat flux and latent heat flux were positively correlated with the percentage of snow cover. The spatial analysis also showed that a significant relationship existed between the surface variables and land cover types, which was not obviously as that for snow cover changes. Finally, six typical study areas were selected to quantitatively analyse the influence of land cover types beneath the snow cover on heat absorption and transfer, which showed that when the land was snow covered, the conversion of forest to farmland can dramatically influence the net radiation and other surface variables, whereas the snow-free land showed significantly reduced influence. Furthermore, compared with typical land cover changes, e.g., the conversion of forest into farmland, the influence of snow cover changes on net radiation and sensible heat flux were 60 % higher than that of land cover changes

  20. Characteristics of KIPT staff by groups of radiation risk

    International Nuclear Information System (INIS)

    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.

  1. Education on radiation risk in primary and middle schools in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Tada, Junichiro [Japan Synchrotron Radiation Research Institute (SPring-8), Mikaduki, Hyogo (Japan)

    1999-09-01

    The (ionizing) radiation appears in the text of social studies in primary and middle school curriculums. The radiation is almost not involved in the text of science. Consequently, pupils know only the examples of disasters caused by the excessive radiation and have no chance to learn real natures and characters of the radiation after the compulsory education course. This situation means difficulties to give a lesson on the radiation risk. Erupting volcanoes, earthquakes and lightning are similar in danger of the excessive radiations. However, few pupils have a supernatural threat for these phenomena that ancient people do, because they have the adequate knowledge for theses after primary and middle school curriculums. This situation is a full of contrast to the case of the radiation on the major sensitivity that they have. The point is to let pupils learn that the radiation is one of the natural phenomena like heat and electricity, those exist before a birth of human being. Natural ionizing radiation sources are recommended for the first teaching material. Pupils know that the radiation is one of commonplace events, then. Radiation is one of the universe elements. Consequently, they will know that human being is evolving with the radiation exposures. The general perception on safety and danger is a kind of antinomy in Japan. A person who is following antinomy accepts only zero risk. Preschool educations will be needed to grow out of an antinomy concept on safety and danger, and to recognize the reality. A comprehensive knowledge should be provided with a full balance for the perception of risk. For an example, prejudices against HIV patients still remain in Japan, due to many belated campaigns on weak infection. People remember danger, and they do not remember the fact that is not dangerous. (Y. Tanaka)

  2. The variability of radiative balance elements and air temperature over the Asian region of Russia

    Directory of Open Access Journals (Sweden)

    E. V. Kharyutkina

    2012-03-01

    Full Text Available The variability of spatial-temporal distribution of temperature and heat balance elements is investigated for the Asian territory of Russia (45–80° N, 60–180° E using JRA-25, NCEP/DOE AMIP-II reanalysis data and observational data for the period of global warming 1979–2008. It is shown that temperature trend over the territory is 1.4 °C for the period under study according to reanalysis data. Since the beginning of 90s of 20th century the increase of back earth-atmosphere shortwave radiation is observed. Such tendency is in conformity with the cloud cover distribution and downward shortwave radiation at the surface. Regression model describing temperature variability with variability of heat balance elements was presented. We conclude that possible applications for the model include the convenient estimate of temperature variability according to reanalysis data.

  3. Balancing Life with an Increased Risk of Cancer

    DEFF Research Database (Denmark)

    Petersen, Helle Vendel; Nilbert, Mef; Bernstein, Inge;

    2014-01-01

    Possibilities to undergo predictive genetic testing for cancer have expanded, which implies that an increasing number of healthy individuals will learn about cancer predisposition. Knowledge about how an increased risk of disease influences life in a long-term perspective is largely unknown, which...... identified and formed the essence of the phenomenon "living with knowledge about risk." Family context influences how experiences and knowledge are interpreted and transformed into thoughts and feelings, which relates to how risk is approached and handled. The constitutions influence each other in a dynamic...

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

    Science.gov (United States)

    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.

  5. Balancing Risks and Benefits of Therapy for Patients with Favorable-Risk Limited-Stage Hodgkin Lymphoma: The Role of ABVD Chemotherapy Alone

    OpenAIRE

    Hay, Annette E.; Meyer, Ralph M.

    2014-01-01

    More than 85% of patients with non-bulky stage IA-IIA Hodgkin lymphoma will obtain long-term disease control. However, as long-term survival is dependent on both disease control and avoidance of late toxic effects associated with the treatment received, the initial choice of treatment can be associated with trade-offs that balance optimum disease control with avoidance of these late-effect risks. Previous radiation therapy paradigms that used wide-field target volumes were the major treatment...

  6. A Cardiovascular Risk Reduction Program for American Indians with Metabolic Syndrome: The Balance Study

    Science.gov (United States)

    Lee, Elisa T.; Jobe, Jared B.; Yeh, Jeunliang; Ali, Tauqeer; Rhoades, Everett R.; Knehans, Allen W.; Willis, Diane J.; Johnson, Melanie R.; Zhang, Ying; Poolaw, Bryce; Rogers, Billy

    2012-01-01

    The Balance Study is a randomized controlled trial designed to reduce cardiovascular disease (CVD) risk in 200 American Indian (AI) participants with metabolic syndrome who reside in southwestern Oklahoma. Major risk factors targeted include weight, diet, and physical activity. Participants are assigned randomly to one of two groups, a guided or a…

  7. Current and future impacts of ultraviolet radiation on the terrestrial carbon balance

    Institute of Scientific and Technical Information of China (English)

    W. Kolby SMITH; Wei GAO; Heidi STELTZER

    2009-01-01

    One of the most documented effects of human activity on our environment is the reduction of stratospheric ozone resulting in an increase of biologically harmful ultraviolet (UV) radiation. In a less predictable manner, UV radiation incident at the surface of the earth is expected to be further modified in the future as a result of altered cloud condition, atmospheric aerosol concentration, and snow cover. Although UV radiation comprises only a small fraction of the total solar radiation that is incident at the earth's surface, it has the greatest energy per unit wavelength and, thus, the greatest potential to damage the biosphere. Recent investigations have highlighted numerous ways that UV radiation could potentially affect a variety of ecological processes, including nutrient cycling and the terrestrial carbon cycle. The objectives of the following literature review are to summarize and synthesize the available information relevant to the effects of UV radiation and other climate change factors on the terrestrial carbon balance in an effort to highlight current gaps in knowledge and future research directions for UV radiation research.

  8. Balancing risk and benefit with oral hypoglycemic drugs.

    Science.gov (United States)

    Hamnvik, Ole-Petter R; McMahon, Graham T

    2009-06-01

    Clinicians are faced with an expansive array of treatment choices when caring for patients with type 2 diabetes. Because patient compliance may be affected when media sensationalism about controversial findings is misunderstood, we sought to clarify the recent controversy surrounding the cardiovascular and bone-health risks of thiazolidinediones, the risk of lactic acidosis with metformin, and the risk of hypoglycemia with oral therapies. The side effect profile of thiazolidinediones includes fluid retention, heart failure; and an increased risk of fracture. A recent controversial meta-analysis suggested that rosiglitazone increases the risk of myocardial infarction, which is possibly related to thiazolidinedione-induced lipid changes, weight gain, congestive heart failure, and anemia. Metformin is restricted to patients with normal renal function because of concerns that metformin may cause lactic acidosis. However, few cases of metformin-associated lactic acidosis have been reported, and most have occurred in patients with other reasons for developing lactic acidosis, such as sepsis or renal failure. Although the use of metformin continues to increase, observational studies have not been able to demonstrate an increased incidence of lactic acidosis in metformin-treated patients, even when it is used in populations with relative contraindications. Some oral hypoglycemic medications can cause hypoglycemia. Hypoglycemia is especially common in older patients, alcoholics, and patients with liver or renal disease. Patients on sulfonylureas and meglitinides have the highest incidence of hypoglycemia because of their pharmacological action of increasing insulin secretion. Of the sulfonylureas, glyburide presents the highest risk of hypoglycemia. Combination therapies, especially those regimens containing a sulfonylurea, increase the risk of hypoglycemia. PMID:19421967

  9. Medical interventional procedures--reducing the radiation risks

    Energy Technology Data Exchange (ETDEWEB)

    Cousins, C. E-mail: claire.cousins@addenbrookes.nhs.uk; Sharp, C

    2004-06-01

    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.

  10. Therapeutic radiation and the potential risk of second malignancies.

    Science.gov (United States)

    Kamran, Sophia C; Berrington de Gonzalez, Amy; Ng, Andrea; Haas-Kogan, Daphne; Viswanathan, Akila N

    2016-06-15

    Radiation has long been associated with carcinogenesis. Nevertheless, it is an important part of multimodality therapy for many malignancies. It is critical to assess the risk of secondary malignant neoplasms (SMNs) after radiation treatment. The authors reviewed the literature with a focus on radiation and associated SMNs for primary hematologic, breast, gynecologic, and pediatric tumors. Radiation appeared to increase the risk of SMN in all of these; however, this risk was found to be associated with age, hormonal influences, chemotherapy use, environmental influences, genetic predisposition, infection, and immunosuppression. The risk also appears to be altered with modern radiotherapy techniques. Practitioners of all specialties who treat cancer survivors in follow-up should be aware of this potential risk. Cancer 2016;122:1809-21. © 2016 American Cancer Society.

  11. Therapeutic radiation and the potential risk of second malignancies.

    Science.gov (United States)

    Kamran, Sophia C; Berrington de Gonzalez, Amy; Ng, Andrea; Haas-Kogan, Daphne; Viswanathan, Akila N

    2016-06-15

    Radiation has long been associated with carcinogenesis. Nevertheless, it is an important part of multimodality therapy for many malignancies. It is critical to assess the risk of secondary malignant neoplasms (SMNs) after radiation treatment. The authors reviewed the literature with a focus on radiation and associated SMNs for primary hematologic, breast, gynecologic, and pediatric tumors. Radiation appeared to increase the risk of SMN in all of these; however, this risk was found to be associated with age, hormonal influences, chemotherapy use, environmental influences, genetic predisposition, infection, and immunosuppression. The risk also appears to be altered with modern radiotherapy techniques. Practitioners of all specialties who treat cancer survivors in follow-up should be aware of this potential risk. Cancer 2016;122:1809-21. © 2016 American Cancer Society. PMID:26950597

  12. Space radiation risks to the central nervous system

    Science.gov (United States)

    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.

  13. Balancing Lymphedema Risk: Exercise Versus Deconditioning for Breast Cancer Survivors

    OpenAIRE

    Schmitz, Kathryn H.

    2010-01-01

    Lymphedema, a common and feared negative effect of breast cancer treatment, is generally described by arm swelling and dysfunction. Risk averse clinical recommendations guided survivors to avoid use of the affected arm. This may lead to deconditioning and, ironically, the very outcome women seek to avoid. Recently published studies run counter to these guidelines.

  14. New Strategies for Managing Risks: A Balancing Act for Boards

    Science.gov (United States)

    Pelletier, Stephen

    2012-01-01

    The stately collegiate gothic buildings that define the iconic West Campus at Duke University evoke a strong sense of stability and the status quo. Like all institutions of higher learning, Duke faces many potential challenges to campus equilibrium--some of which could prove devastating to the university. Risk is inherent in academe, yet colleges…

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

  17. Radiation Risks and Mitigation in Electronic Systems

    CERN Document Server

    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...

  18. Radiation and society: Comprehending radiation risk. V. 3. Proceedings of an international conference

    International Nuclear Information System (INIS)

    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 three of the proceedings contains the speeches, ten introductory papers, summaries of the technical discussion sessions, the key note paper on uncertainties in the health impact of environmental pollutants. Refs, figs, tabs

  19. Interaction between radiation and other breast cancer risk factors

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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

  1. Carcinogenic risks associated with radiation pollution. [UV radiation, sunlight

    Energy Technology Data Exchange (ETDEWEB)

    Latarjet, R.

    1976-01-01

    The cancerogenic pollution by non-ionizing radiations is limited to the case of solar ultraviolet, whose activity at ground level may be increased as a consequence of the stratospheric depletion of ozone, produced by certain chemical pollutants: nitrogen oxides from supersonic aircrafts, freon. As regards ionizing radiations, the discussion is focused on the fundamental problem of the threshold, and on the means by which one may obtain some quantitative data related to carcinogenesis by small radiation doses in man. A new concept, that of a practical threshold, is proposed. A theory which links radiocancerogenesis, as well as chemical cancerogenesis, to errors produced in the repair of lesions in the DNA is discussed. The rads-equivalent project for chemical mutagens and carcinogens is described.

  2. Energy and carbon balances in cheatgrass, an essay in autecology. [Shortwave radiation, radiowave radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hinds, W.T.

    1975-01-01

    An experiment to determine the fates of energy and carbon in cheatgrass (Bromus tectorum L.) was carried out on steep (40/sup 0/) north- and south-facing slopes on a small earth mound, using many small lysimeters to emulate swards of cheatgrass. Meteorological conditions and energy fluxes that were measured included air and soil temperatures, relative humidity, wind speed, incoming shortwave radiation, net all-wave radiation, heat flux to the soil, and evaporation and transpiration separately. The fate of photosynthetically fixed carbon during spring growth was determined by analysis of the plant tissues into mineral nutrients, crude protein, crude fat, crude fiber, and nitrogen-free extract (NFE) for roots, shoots, and seeds separately. (auth)

  3. Social impacts induced by radiation risk in Fukushima prefecture

    International Nuclear Information System (INIS)

    An accident of Fukushima Daiichi nuclear power plant induced by an earthquake of M9.0 and subsequent tsunami gave various kinds of impacts around the plant. After reviewing arguments of local governments for low dose radiation risk, this paper analyzed social impacts by the risk in terms of a gap of emergency response between national and local governments, corruption of communities in various levels induced by plural statements for risk levels in low level radiation, and economic impacts for agricultural crops made in Fukushima prefecture. Afterwards, clues for improving the situation were discussed, which include understanding of characteristics of public perception, attitudes of experts and interactive risk communication. (author)

  4. Scientific approach to radiation-induced cancer risk

    OpenAIRE

    Sobue, Tomotaka

    2011-01-01

    When evaluating cancer risk of low-dose radiation, it is difficult to distinguish the actual effect from that of chance, bias, and confounding as they become relatively large. This is why the relation between radiation doses of less than 100 mSv and cancer risk is considered unknown. Based on data of atomic bomb survivors in Hiroshima and Nagasaki, the cancer risk at 100 mSv is calculated at 1.05 times. On the other hand, the risk ratio for the relation between passive smoking and lung cancer...

  5. Risks and management of radiation exposure.

    Science.gov (United States)

    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

  6. The Influence of Light Absorbing Aerosols on the Radiation Balance Over Central Greenland

    Science.gov (United States)

    Strellis, B.; Bergin, M. H.; Sokolik, I. N.; Dibb, J. E.; Sheridan, P. J.; Ogren, J. A.

    2011-12-01

    The Arctic region has proven to be more responsive to recent changes in climate than other parts of the Earth. A key component of the Arctic climate is the Greenland Ice Sheet, which has the potential to dramatically influence both sea level, depending on the amount of melting that occurs, and climate, through shifts in the regional radiation balance. Light absorbing aerosols from biomass burning, fossil fuel combustion, and dust sources can potentially have a significant impact on the radiation balance of the ice sheet, although at this time we lack the key measurements needed to accurately quantify aerosol forcing over the ice sheet. For this reason a field study was conducted at Summit, Greenland, from May-July of 2012. Our efforts included real-time measurements of aerosol physical and optical properties including size distribution, multi-wavelength scattering (σsp) and backscattering (σbsp) coefficients, and multi-wavelength absorption coefficient (σap), as well as measurements of wavelength dependent aerosol optical depth and spectral snow albedo. The measurements serve as inputs to a radiative transfer model to estimate the direct aerosol radiative forcing at both the surface and top of the atmosphere. Preliminary results indicate that the direct aerosol radiative forcing is often several Wm-2 and is at times greater than 10 Wm-2. The aerosol chemical composition (major ions, elements, and organic and elemental carbon compounds) was also determined through filter sampling and will be discussed in terms of the sources of light absorbing aerosols over central Greenland.

  7. Instrumentation and control balancing the risks and benefits of modernization

    International Nuclear Information System (INIS)

    This paper examines the benefits and risks of modernization of instrumentation and control (I and C) systems for nuclear power plants. It will draw conclusions on how to proceed with such modernization across the spectrum from operating reactors to new plant designs. Lessons learned from Westinghouse's application of digital systems to the Temelin Nuclear Power Plant in the Czech Republic, and other nuclear plant upgrades will be used to support principles and conclusions drawn in the paper. A long term view of the modernization program is essential, even if piecemeal or individual upgrades are envisioned. A framework for considering these risks and goals into a long range strategic plan will be presented. The framework will be presented in the form of I and C architectures which permit long term growth, planning ahead for technological obsolescence, selectron of suppliers for term relationships, and effective integration of individual upgrades. Potential upgrade areas will be summarized for functional improvements, I and C hardware upgrades, and man-machine interface improvements. Examples from Westinghouse's I and C experience will be presented to clarify the principles and framework described in the paper. Lessons learned from the application of the Eagle product line to operating reactors and the emergence of distributed computer information systems as an integration vehicle for I and C upgrades will be discussed. Westinghouse is currently modernizing the Temelin Nuclear Power Plant I and C system in the Czech Republic. An overview of this program will be included as it relates to the modernization framework presented in the paper. (authors)

  8. Probabilistic Assessment of Radiation Risk for Astronauts in Space Missions

    Science.gov (United States)

    Kim, Myung-Hee; DeAngelis, Giovanni; Cucinotta, Francis A.

    2009-01-01

    Accurate predictions of the health risks to astronauts from space radiation exposure are necessary for enabling future lunar and Mars missions. Space radiation consists of solar particle events (SPEs), comprised largely of medium energy protons, (less than 100 MeV); and galactic cosmic rays (GCR), which include protons and heavy ions of higher energies. While the expected frequency of SPEs is strongly influenced by the solar activity cycle, SPE occurrences themselves are random in nature. A solar modulation model has been developed for the temporal characterization of the GCR environment, which is represented by the deceleration potential, phi. The risk of radiation exposure from SPEs during extra-vehicular activities (EVAs) or in lightly shielded vehicles is a major concern for radiation protection, including determining the shielding and operational requirements for astronauts and hardware. To support the probabilistic risk assessment for EVAs, which would be up to 15% of crew time on lunar missions, we estimated the probability of SPE occurrence as a function of time within a solar cycle using a nonhomogeneous Poisson model to fit the historical database of measurements of protons with energy > 30 MeV, (phi)30. The resultant organ doses and dose equivalents, as well as effective whole body doses for acute and cancer risk estimations are analyzed for a conceptual habitat module and a lunar rover during defined space mission periods. This probabilistic approach to radiation risk assessment from SPE and GCR is in support of mission design and operational planning to manage radiation risks for space exploration.

  9. Cancer risk from low doses of ionizing radiation

    International Nuclear Information System (INIS)

    The aim of the study was to estimate cancer risk from small doses of ionizing radiation from various sources, including both external and internal exposure. The types of radiation included alpha, gamma, and neutron radiation. A nationwide follow-up study covering the years up to 1992 revealed no significant association between fallout from the Chernobyl accident and incidence of childhood leukemia. An excess of eight cases or more per year could be excluded. However, some indication of an increase was evident in the most heavily affected areas. Furthermore, the risk estimates were in accordance with those reported from Hiroshima and Nagasaki, although the confidence intervals were wide. (282 refs.)

  10. Risk evaluation for protection of the public in radiation accidents

    International Nuclear Information System (INIS)

    Evaluation of the risk that would be involved in the exposure of the public in the event of a radiation accident requires information on the biological consequences expected of such an exposure. This report defines a range of reference doses of radiation and their corresponding risks to the public in the event of a radiation accident. The reference doses and the considerations on which they were based will be used for assessing the hazards of nuclear installations and for policy decisions by the authorities responsible for measures taken to safeguards the public in the case of a nuclear accident.

  11. Cancer risk from low doses of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Auvinen, A.

    1997-06-01

    The aim of the study was to estimate cancer risk from small doses of ionizing radiation from various sources, including both external and internal exposure. The types of radiation included alpha, gamma, and neutron radiation. A nationwide follow-up study covering the years up to 1992 revealed no significant association between fallout from the Chernobyl accident and incidence of childhood leukemia. An excess of eight cases or more per year could be excluded. However, some indication of an increase was evident in the most heavily affected areas. Furthermore, the risk estimates were in accordance with those reported from Hiroshima and Nagasaki, although the confidence intervals were wide. (282 refs.).

  12. Influences of deforestation on radiation and heat balances in tropical peat swamp forest in Thailand

    International Nuclear Information System (INIS)

    The difference of radiation and heat balances between a natural peat swamp forest and a deforested secondary forest has been investigated in Narathiwat Province, Thailand. Micrometeorological measurements were conducted continuously on observation towers 38 m and 4 m in heights in the primary forest and the secondary forest respectively. Results show that the deforestation of peat swamp forest leads to an increase in the sensible heat flux in the secondary forest. The yearly average ratio of the sensible heat flux to the net radiation was 20.9% in the peat swamp forest, and 33.2% in the secondary forest from Aug. 1995 to Jul. 1996. A ratio more than 40% was observed only in the dry season in the secondary forest. The change in sensible heat flux seemed to be influenced by the change in ground water levels. (author)

  13. Radiation balance at the surface in the city of São Paulo, Brazil: diurnal and seasonal variations

    NARCIS (Netherlands)

    Ferreira, M.J.; Oliveira, de A.P.; Soares, J.; Codato, G.; Wilde Barbaro, E.; Escobedo, J.F.

    2012-01-01

    The main goal of this work is to describe the diurnal and seasonal variations of the radiation balance components at the surface in the city of São Paulo based on observations carried out during 2004. Monthly average hourly values indicate that the amplitudes of the diurnal cycles of net radiation (

  14. Radiation and cancer risk in atomic-bomb survivors.

    Science.gov (United States)

    Kodama, K; Ozasa, K; Okubo, T

    2012-03-01

    With the aim of accurately assessing the effects of radiation exposure in the Japanese atomic-bomb survivors, the Radiation Effects Research Foundation has, over several decades, conducted studies of the Life Span Study (LSS) cohort, comprising 93 000 atomic-bomb survivors and 27 000 controls. Solid cancer: the recent report on solid cancer incidence found that at age 70 years following exposure at age 30 years, solid cancer rates increase by about 35%  Gy(-1) for men and 58% Gy(-1) for women. Age-at-exposure is an important risk modifier. In the case of lung cancer, cigarette smoking has been found to be an important risk modifier. Radiation has similar effects on first-primary and second-primary cancer risks. Finally, radiation-associated increases in cancer rates appear to persist throughout life. Leukaemia: the recent report on leukaemia mortality suggests that radiation effects on leukaemia mortality persisted for more than 50 years. Moreover, significant dose-response for myelodysplastic syndrome was observed in Nagasaki LSS members even 40-60 years after radiation exposure. Future perspective: given the continuing solid cancer increase in the survivor population, the LSS will likely continue to provide important new information on radiation exposure and solid cancer risks for another 15-20 years, especially for those exposed at a young age. PMID:22394591

  15. Radiation risk estimation based on measurement error models

    CERN Document Server

    Masiuk, Sergii; Shklyar, Sergiy; Chepurny, Mykola; Likhtarov, Illya

    2016-01-01

    This monograph discusses statistics and risk estimates applied to radiation damage under the presence of measurement errors. The first part covers nonlinear measurement error models, with a particular emphasis on efficiency of regression parameter estimators. In the second part, risk estimation in models with measurement errors is considered. Efficiency of the methods presented is verified using data from radio-epidemiological studies.

  16. Risky business: challenges and successes in military radiation risk communication.

    Science.gov (United States)

    Melanson, Mark A; Geckle, Lori S; Davidson, Bethney A

    2012-01-01

    Given the general public's overall lack of knowledge about radiation and their heightened fear of its harmful effects, effective communication of radiation risks is often difficult. This is especially true when it comes to communicating the radiation risks stemming from military operations. Part of this difficulty stems from a lingering distrust of the military that harkens back to the controversy surrounding Veteran exposures to Agent Orange during the Vietnam War along with the often classified nature of many military operations. Additionally, there are unique military exposure scenarios, such as the use of nuclear weapons and combat use of depleted uranium as antiarmor munitions that are not found in the civilian sector. Also, the large, diverse nature of the military makes consistent risk communication across the vast and widespread organization very difficult. This manuscript highlights and discusses both the common and the distinctive challenges of effectively communicating military radiation risks, to include communicating through the media. The paper also introduces the Army's Health Risk Communication Program and its role in assisting in effective risk communication efforts. The authors draw on their extensive collective experience to share 3 risk communication success stories that were accomplished through the innovative use of a matrixed, team approach that combines both health physics and risk communication expertise.

  17. [Carcinogenic risks associated with radiation pollution].

    Science.gov (United States)

    Latarjet, R

    1976-01-01

    1. The cancerogenic pollution by non-ionizing radiations is limited to the case of solar ultraviolet, whose activity at ground level may be increased as a consequence of the stratospheric depletion of ozone, itself produced by certain chemical pollutants: nitrogen oxydes from supersonic aircrafts, freon. 2. As regards ionizing radiations, the discussion is focused on the fundamental problem of the "threshold", aand on the means by which one may obtain some quantitative data related to carcinogenesis by small radiation doses in Man. A new concept, that of a "practical threshold" is proposed. 3. One discusses a theory which links radiocancerogenesis, as well as chemical cancerogenesis, to errors produced in the repair of lesions in the DNA. 4. One presents and discusses the "rads-equivalent" project for chemical mutagens and cancerogens.

  18. Factors that modify risks of radiation-induced cancer

    International Nuclear Information System (INIS)

    The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors)

  19. Factors that modify risks of radiation-induced cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1988-11-01

    The collective influence of biologic and physical factors that modify risks of radiation-induced cancer introduces uncertainties sufficient to deny precision of estimates of human cancer risk that can be calculated for low-dose radiation in exposed populations. The important biologic characteristics include the tissue sites and cell types, baseline cancer incidence, minimum latent period, time-to-tumor recognition, and the influence of individual host (age and sex) and competing etiologic influences. Physical factors include radiation dose, dose rate, and radiation quality. Statistical factors include time-response projection models, risk coefficients, and dose-response relationships. Other modifying factors include other carcinogens, and other biological sources (hormonal status, immune status, hereditary factors).

  20. Radiation balance of dryland grain sorghum as affected by planting geometry

    International Nuclear Information System (INIS)

    The effects of planting geometry on the radiation balance of dryland grain sorghum (Sorghum bicolor L. cv. DK 46) were studied in a field experiment at the USDA-ARS Conservation and Production Research Laboratory at Bushland, TX, in 1984 on a Pullman clay loam (a fine, mixed, thermic Torrertic Paleustoll). The objective was to reduce the radiation load on a crop through manipulation of planting geometry and to determine whether that would affect crop productivity. Net radiation was 5% higher over wide compared to narrow rows (0.76 and 0.38 m, respectively) when averaged over three population levels from 33 to 110 days after sowing. East-west rows had 14% higher net radiation than north-south rows, averaged over two row spacings. The differences in net radiation were due to daytime responses, presumably shortwave albedo differences. Leaf photosynthesis and transpiration rates and stomatal resistance were measured twice during the grain-filling period. These measurements, taken S days after a period of moderate rains, showed no differences in the plant response due to row spacing or direction treatments. Slightly higher leaf temperatures in the high-population plots may have been related to greater depletion of plant available water than in medium and low population plots (72, 66, and 67% depletion, respectively). After 1 weeks of drying, narrow-row and high-population treatments showed greater stress as evidenced by lower transpiration and photosynthesis rates and higher stomatal resistance and leaf temperature. Soil water depletion was 20% less in narrow than wide rows during a 2-week period spanning the leaf transpiration measurement dates. Leaf photosynthesis, transpiration, temperature, and stomatal resistance were not affected by differences in net radiation due to row spacing or row direction

  1. EDITORIAL: The Earth radiation balance as driver of the global hydrological cycle

    Science.gov (United States)

    Wild, Martin; Liepert, Beate

    2010-06-01

    Variations in the intensity of the global hydrological cycle can have far-reaching effects on living conditions on our planet. While climate change discussions often revolve around possible consequences of future temperature changes, the adaptation to changes in the hydrological cycle may pose a bigger challenge to societies and ecosystems. Floods and droughts are already today amongst the most damaging natural hazards, with floods being globally the most significant disaster type in terms of loss of human life (Jonkman 2005). From an economic perspective, changes in the hydrological cycle can impose great pressures and damages on a variety of industrial sectors, such as water management, urban planning, agricultural production and tourism. Despite their obvious environmental and societal importance, our understanding of the causes and magnitude of the variations of the hydrological cycle is still unsatisfactory (e.g., Ramanathan et al 2001, Ohmura and Wild 2002, Allen and Ingram 2002, Allan 2007, Wild et al 2008, Liepert and Previdi 2009). The link between radiation balance and hydrological cycle Globally, precipitation can be approximated by surface evaporation, since the variability of the atmospheric moisture storage is negligible. This is the case because the fluxes are an order of magnitude larger than the atmospheric storage (423 x 1012 m3 year-1 versus 13 x 1012 m3 according to Baumgartner and Reichel (1975)), the latter being determined by temperature (Clausius-Clapeyron). Hence the residence time of evaporated water in the atmosphere is not more than a few days, before it condenses and falls back to Earth in the form of precipitation. Any change in the globally averaged surface evaporation therefore implies an equivalent change in precipitation, and thus in the intensity of the global hydrological cycle. The process of evaporation requires energy, which it obtains from the surface radiation balance (also known as surface net radiation), composed of the

  2. Risk of occupational radiation-induced cataract in medical workers

    International Nuclear Information System (INIS)

    The objective of this study was determination of criteria for recognition of a pre senile cataract as a professional disease in health care personnel exposed to small doses of ionizing radiation. Method: The study included 3240 health workers in medical centers of Serbia in the period 1992-2002. A total of 1560 workers were employed in the zone (group A) and 1680 out of ionizing radiation zone (group B). Among group A, two groups had been selected: 1. Group A-1: Health workers in the ionizing radiation zone who contracted lens cataract during their years of service while dosimetry could not reveal higher absorbed dose (A-1=115); 2. Group A-2: Health workers in the ionizing radiation zone with higher incidence of chromosomal aberrations and without cataract (A-2=100). Results: More significant incidence of cataract was found in group A, χ2=65.92; p<0.01. Radiation risk was higher in health workers in radiation zone than in others, relative risk is 4, 6. Elevated blood sugar level was found in higher percentage with health workers working in radiation zone who developed cataract. Conclusion: Low doses of radiation are not the cause of occupational cataract as individual occupational disease. X-ray radiation may be a significant cofactor of cataract in radiological technicians. (author)

  3. Radiation protection issues in galactic cosmic ray risk assessment

    Science.gov (United States)

    Sinclair, W. K.

    1994-10-01

    Radiation protection involves the limitation of exposure to below threshold doses for direct (or deterministic) effects and a knowledge of the risk of stochastic effects after low doses. The principal stochastic risk associated with low dose rate galactic cosmic rays is the increased risk of cancer. Estimates of this risk depend on two factors (a) estimates of cancer risk for low-LET radiation and (b) values of the appropriate radiation weighting factors, wR, for the high-LET radiations of galactic cosmic rays. Both factors are subject to considerable uncertainty. The low-LET cancer risk derived from the late effects of the atomic bombs is vulnerable to a number of uncertainties including especially that from projection in time, and from extrapolation from high to low dose rate. Nevertheless, recent low dose studies of workers and others tend to confirm these estimates. wR, relies on biological effects studied mainly in non-human systems. Additional laboratory studies could reduce the uncertainties in wR and thus produce a more confident estimate of the overall risk of galactic cosmic rays.

  4. Radiation protection issues in galactic cosmic ray risk assessment

    Science.gov (United States)

    Sinclair, W. K.

    1994-01-01

    Radiation protection involves the limitation of exposure to below threshold doses for direct (or deterministic) effects and a knowledge of the risk of stochastic effects after low doses. The principal stochastic risk associated with low dose rate galactic cosmic rays is the increased risk of cancer. Estimates of this risk depend on two factors (a) estimates of cancer risk for low-LET radiation and (b) values of the appropriate radiation weighting factors, WR, for the high-LET radiations of galactic cosmic rays. Both factors are subject to considerable uncertainty. The low-LET cancer risk derived from the late effects of the atomic bombs is vulnerable to a number of uncertainties including especially that from projection in time, and from extrapolation from high to low dose rate. Nevertheless, recent low dose studies of workers and others tend to confirm these estimates. WR, relies on biological effects studied mainly in non-human systems. Additional laboratory studies could reduce the uncertainties in WR and thus produce a more confident estimate of the overall risk of galactic cosmic rays.

  5. Regional Modeling of Dust Mass Balance and Radiative Forcing over East Asia using WRF-Chem

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Siyu; Zhao, Chun; Qian, Yun; Leung, Lai-Yung R.; Huang, J.; Huang, Zhongwei; Bi, Jianrong; Zhang, Wu; Shi, Jinsen; Yang, Lei; Li, Deshuai; Li, Jinxin

    2014-12-01

    The Weather Research and Forecasting model with Chemistry (WRF-Chem) is used to investigate the seasonal and annual variations of mineral dust over East Asia during 2007-2011, with a focus on the dust mass balance and radiative forcing. A variety of measurements from in-stu and satellite observations have been used to evaluate simulation results. Generally, WRF-Chem reproduces not only the column variability but also the vertical profile and size distribution of mineral dust over and near the dust source regions of East Asia. We investigate the dust lifecycle and the factors that control the seasonal and spatial variations of dust mass balance and radiative forcing over the seven sub-regions of East Asia, i.e. source regions, the Tibetan Plateau, Northern China, Southern China, the ocean outflow region, and Korea-Japan regions. Results show that, over the source regions, transport and dry deposition are the two dominant sinks. Transport contributes to ~30% of the dust sink over the source regions. Dust results in a surface cooling of up to -14 and -10 W m-2, atmospheric warming of up to 20 and 15 W m-2, and TOA cooling of -5 and -8 W m-2 over the two major dust source regions of East Asia, respectively. Over the Tibetan Plateau, transport is the dominant source with a peak in summer. Over identified outflow regions, maximum dust mass loading in spring is contributed by the transport. Dry and wet depositions are the comparably dominant sinks, but wet deposition is larger than dry deposition over the Korea-Japan region, particularly in spring (70% versus 30%). The WRF-Chem simulations can generally capture the measured features of dust aerosols and its radaitve properties and dust mass balance over East Asia, which provides confidence for use in further investigation of dust impact on climate over East Asia.

  6. Attributable risk for radiation in the presence of other risk factors.

    Science.gov (United States)

    Cologne, John; Cullings, Harry; Furukawa, Kyoji; Ross, Phillip

    2010-11-01

    Two motivations for studying radiation risk are (1) to quantify the magnitude of risk as an aid to setting radiation protection standards and (2) to understand causality as an aid to assigning compensation for radiation exposed individuals whose disease or death may have been related to radiation exposure. Although it has long been known that radiation risk is modified by factors such as sex, age, and time, it is now apparent that radiation risk may also be modified by other risk factors, such as smoking, inflammation, genotype, and certain pathogens. Even apart from considerations of etiological interaction, the relative contribution of radiation to total burden of disease or death may depend on the level of background (spontaneous) risk of disease or death owing to those other factors if the joint effects do not multiply. Therefore, ignoring those other factors in assessing probability of causation for radiation (attributable fraction in epidemiological data) involves making a strong assumption about the joint effects. The concepts are discussed in detail and illustrated using results from studies on the Japanese atomic-bomb survivors. PMID:20938230

  7. Temporal variation of optimal UV exposure time over Korea: risks and benefits of surface UV radiation

    Science.gov (United States)

    Lee, Y. G.; Koo, J. H.

    2015-12-01

    Solar UV radiation in a wavelength range between 280 to 400 nm has both positive and negative influences on human body. Surface UV radiation is the main natural source of vitamin D, providing the promotion of bone and musculoskeletal health and reducing the risk of a number of cancers and other medical conditions. However, overexposure to surface UV radiation is significantly related with the majority of skin cancer, in addition other negative health effects such as sunburn, skin aging, and some forms of eye cataracts. Therefore, it is important to estimate the optimal UV exposure time, representing a balance between reducing negative health effects and maximizing sufficient vitamin D production. Previous studies calculated erythemal UV and vitamin-D UV from the measured and modelled spectral irradiances, respectively, by weighting CIE Erythema and Vitamin D3 generation functions (Kazantzidis et al., 2009; Fioletov et al., 2010). In particular, McKenzie et al. (2009) suggested the algorithm to estimate vitamin-D production UV from erythemal UV (or UV index) and determined the optimum conditions of UV exposure based on skin type Ⅱ according to the Fitzpatrick (1988). Recently, there are various demands for risks and benefits of surface UV radiation on public health over Korea, thus it is necessary to estimate optimal UV exposure time suitable to skin type of East Asians. This study examined the relationship between erythemally weighted UV (UVEry) and vitamin D weighted UV (UVVitD) over Korea during 2004-2012. The temporal variations of the ratio (UVVitD/UVEry) were also analyzed and the ratio as a function of UV index was applied in estimating the optimal UV exposure time. In summer with high surface UV radiation, short exposure time leaded to sufficient vitamin D and erythema and vice versa in winter. Thus, the balancing time in winter was enough to maximize UV benefits and minimize UV risks.

  8. Regulatory assessment of risk to the environment: Radiation

    International Nuclear Information System (INIS)

    'Health, Safety and Environment' is a familiar catchphrase in today's government departments, universities and industry. This catchphrase is most often associated with terms such as 'risk assessment', 'risk management' and 'hazard identification'. Such grouping demonstrates the underlying assumption that 'risk(s)' to the environment can be dealt with, and are being dealt with, using the same processes as those used for evaluating health and safety risks. This equally applies when the hazard is radiation. Management of risk to the environment is often carried out within a framework of an Environmental Impact Assessment (EIA) incorporating Risk Assessment (RA) processes. Environmental Management Systems (EMS) and Risk Management Systems (RMS) also provide frameworks which incorporate RA processes. These systems are often integrated with existing quality and safety systems. The steps in these frameworks have been explained and comparisons have been drawn of how an EIA process and Environmental Management System compare with Environmental Risk Management processes. These comparisons demonstrate the common elements of each framework. The Australian Standard for Risk Management (AS/NZS 4360:1999) describes the risk management process in terms of establishing a risk context, identification, analysis, evaluation and treatment of risks. The application of risk management procedures as described in the Australian Standard for Risk Management have been discussed in relation to how they might apply to a simple case scenario of a historical landfill containing radioactive waste. (author)

  9. Harmonization of risk management approaches: radiation and chemical exposures

    International Nuclear Information System (INIS)

    Assessment of occupational and public risk from the environmental pollutants like chemicals, radiation, etc demands that the effects be considered not only from each individual pollutant, but from the combination of all the pollutants. An integrated risk assessment system needs to be in place to have an overall risk perspective for the benefit of policy makers and decision takers to try to achieve risk reduction in totality. The basis for risk-based radiation dose limits is derived from epidemiological studies, which provide a rich source of data largely unavailable to chemical risk assessors. In addition, use of the principle of optimization as expressed in the ALARA concept has resulted in a safety culture, which is much more than just complying with stipulated limits. The conservative hypothesis of no-threshold dose-effect relation (ICRP) is universally assumed. The end-points and the severity of different classes of pollutants and even different pollutants in a same class vary over a wide range. Hence, it is difficult to arrive at a quantitative value for the net detriment that weighs the various types of end-points and various classes of pollutants. Once the risk due to other pollutants is quantified by some acceptable methodology, it can be expressed in terms of the Risk Equivalent Radiation Dose (R.E.R.D.) for easy comparison with options involving radiation exposure. This paper is an effort to use to quantify and present the risk due to exposure to chemicals and radiation in a common scale for the purpose of easy comparison to facilitate decision taking. (authors)

  10. Harmonization of risk management approaches: radiation and chemical exposures

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, P. [Bhabha Atomic Research Centre, Radiation Safety Systems Div., Mumbai (India)

    2006-07-01

    Assessment of occupational and public risk from the environmental pollutants like chemicals, radiation, etc demands that the effects be considered not only from each individual pollutant, but from the combination of all the pollutants. An integrated risk assessment system needs to be in place to have an overall risk perspective for the benefit of policy makers and decision takers to try to achieve risk reduction in totality. The basis for risk-based radiation dose limits is derived from epidemiological studies, which provide a rich source of data largely unavailable to chemical risk assessors. In addition, use of the principle of optimization as expressed in the ALARA concept has resulted in a safety culture, which is much more than just complying with stipulated limits. The conservative hypothesis of no-threshold dose-effect relation (ICRP) is universally assumed. The end-points and the severity of different classes of pollutants and even different pollutants in a same class vary over a wide range. Hence, it is difficult to arrive at a quantitative value for the net detriment that weighs the various types of end-points and various classes of pollutants. Once the risk due to other pollutants is quantified by some acceptable methodology, it can be expressed in terms of the Risk Equivalent Radiation Dose (R.E.R.D.) for easy comparison with options involving radiation exposure. This paper is an effort to use to quantify and present the risk due to exposure to chemicals and radiation in a common scale for the purpose of easy comparison to facilitate decision taking. (authors)

  11. Estimation of radiation risks at low dose

    International Nuclear Information System (INIS)

    The report presents a review of the effects caused by radiation in low doses, or at low dose rates. For the inheritable (or ''genetic''), as well as for the cancer producing effects of radiation, present evidence is consistent with: (a) a non-linear relationship between the frequency of at least some forms of these effects, with comparing frequencies caused by doses many times those received annually from natural sources, with those caused by lower doses; (b) a probably linear relationship, however, between dose and frequency of effects for dose rates in the region of that received from natural sources, or at several times this rate; (c) no evidence to indicate the existence of a threshold dose below which such effects are not produced, and a strong inference from the mode of action of radiation on cells at low dose rates that no such thresholds are likely to apply to the detrimental, cancer-producing or inheritable, effects resulting from unrepaired damage to single cells. 19 refs

  12. Prenatal radiation risk to the brain

    International Nuclear Information System (INIS)

    The Central Nervous System (CNS) exhibits a high sensitivity to ionizing radiation from conception until after birth. X-irradiation damage of the nervous system during development has been well documented and exposure to ionizing radiation above approximately 10 cGy during perinatal development is contraindicated. Shielding of the embryo or fetus usually prevents gross malformations but high energy irradiation of the pregnant female may result in embryonic growth retardation. This may be especially true when the irradiation is coupled with an ethanol-induced reduction in SOD activity. The synergistic interactions between other drugs and ionizing radiation also have been demonstrated. However, the concentration of endogenous compounds such as histamine and serotonin may be increased in the maternal circulation following irradiation and reach the fetal CNS through a blood-brain-barrier that is more permiable than normal. The introduction of histamine and/or serotonin into the fetal circulation may result in fetal hypotension, edema, cerebral ischemia, and damage to the developing CNS. 48 references

  13. Earth radiation balance as observed and represented in CMIP5 models

    Science.gov (United States)

    Wild, Martin; Folini, Doris; Schär, Christoph; Loeb, Norman; König-Langlo, Gert

    2014-05-01

    The genesis and evolution of Earth's climate is largely regulated by the Earth radiation balance. Despite of its key role in the context of climate change, substantial uncertainties still exist in the quantification of the magnitudes of its different components, and its representation in climate models. While the net radiative energy flows in and out of the climate system at the top of atmosphere are now known with considerable accuracy from new satellite programs such as CERES and SORCE, the energy distribution within the climate system and at the Earth's surface is less well determined. Accordingly, the magnitudes of the components of the surface energy balance have recently been controversially disputed, and potential inconsistencies between the estimated magnitudes of the global energy and water cycle have been emphasized. Here we summarize this discussion as presented in Chapter 2.3 of the 5th IPCC assessment report (AR5). In this context we made an attempt to better constrain the magnitudes of the surface radiative components with largest uncertainties. In addition to satellite observations, we thereby made extensive use of the growing number of surface observations to constrain the radiation balance not only from space, but also from the surface. We combined these observations with the latest modeling efforts performed for AR5 (CMIP5) to infer best estimates for the global mean surface radiative components. Our analyses favor global mean values of downward surface solar and thermal radiation near 185 and 342 Wm-2, respectively, which are most compatible with surface observations (Wild et al. 2013). These estimates are on the order of 10 Wm-2 lower and higher, respectively, than in some of the previous global energy balance assessments, including those presented in previous IPCC reports. It is encouraging that these estimates, which make full use of the information contained in the surface networks, coincide within 2 Wm-2 with the latest satellite

  14. A mathematical foundation for controlling radiation health risks

    International Nuclear Information System (INIS)

    Radiation protection is to attain an adequate control of radiation health risk compared with other risks. Our society in the 21st century is predicted by some experts to seek the high priority of safety for expanding activity of human beings. The law of controlling risks will be a key subject to serve the safety of human beings and their environment. The main principles of the ICRP system of radiological system are strongly relating to the general law of various risk controls. The individual-based protection concept clearly gives us a mathematical model of controlling risks in general. This paper discusses the simplest formulation of controlling risks in the ICRP system, including other relating systems. First, the basic characteristics of occupational exposure as a risk control is presented by analyzing the data compiled over half a century. It shows the relation ship between dose control levels and individually controlled doses. The individual-based control also exerts some influence on the resultant collective dose. The study of occupational exposure concludes the simple mathematical expression of controlling doses under the ICRP system as shown by Kumazawa and Numakunai. Second, the typical characteristics of biological effects with repair or recovery of bio-systems are given by analyzing the data published. Those show the relationship between dose and biologically controlled or regulated response. The bio-system is undoubtedly relating to cybernetics that contains many functions of controlling risks. Consequently radiation effects might somewhat express the feature of biological risk controls. The shouldered survival of irradiated cells shows cybernetic characteristics that are assumed to be the mathematical foundation of controlling risks. The dose-response relationship shows another type of cybernetic characteristics, which could be reduced to the same basic form of controlling risks. The limited study of radiation effects definitely confirms the two

  15. Ionizing radiation risks to satellite power systems (SPS) workers

    International Nuclear Information System (INIS)

    The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment were examined. For ionizing radiation, the major concern will be late or delayed health effects, particularly the increased risk of radiation-induced cancer. The estimated lifetime risk for cancer is 0.8 to 5.0 excess deaths per 10,000 workers per rad of exposure. Thus, for example, in 10,000 workers who completed ten missions with an exposure of 40 rem per mission, 320 to 2000 additional deaths in excess of the 1640 deaths from normally occurring cancer, would be expected. These estimates would indicate a 20 to 120% increase in cancer deaths in the worker-population. The wide range in these estimates stems from the choice of the risk-projection model and the dose-response relationsip. The choice between a linear and a linear-quadratic dose-response model may alter the risk estimate by a factor of about two. The method of analysis (e.g., relative vs absolute risk model) can alter the risk estimate by an additional factor of three. Choosing different age and sex distributions can further change the estimate by another factor of up to three. The potential genetic consequences could be of significance, but at the present time, sufficient information on the age and sex distribution of the worker population is lacking for precise estimation of risk. The potential teratogenic consequences resulting from radiation are considered significant. Radiation exposure of a pregnant worker could result in developmental abnormalities

  16. Ionizing radiation risks to satellite power systems (SPS) workers

    Energy Technology Data Exchange (ETDEWEB)

    Lyman, J.T.; Ainsworth, E.J.; Alpen, E.L.; Bond, V.; Curtis, S.B.; Fry, R.J.M.; Jackson, K.L.; Nachtwey, S.; Sondhaus, C.; Tobias, C.A.; Fabrikant, J.I.

    1980-11-01

    The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment were examined. For ionizing radiation, the major concern will be late or delayed health effects, particularly the increased risk of radiation-induced cancer. The estimated lifetime risk for cancer is 0.8 to 5.0 excess deaths per 10,000 workers per rad of exposure. Thus, for example, in 10,000 workers who completed ten missions with an exposure of 40 rem per mission, 320 to 2000 additional deaths in excess of the 1640 deaths from normally occurring cancer, would be expected. These estimates would indicate a 20 to 120% increase in cancer deaths in the worker-population. The wide range in these estimates stems from the choice of the risk-projection model and the dose-response relationsip. The choice between a linear and a linear-quadratic dose-response model may alter the risk estimate by a factor of about two. The method of analysis (e.g., relative vs absolute risk model) can alter the risk estimate by an additional factor of three. Choosing different age and sex distributions can further change the estimate by another factor of up to three. The potential genetic consequences could be of significance, but at the present time, sufficient information on the age and sex distribution of the worker population is lacking for precise estimation of risk. The potential teratogenic consequences resulting from radiation are considered significant. Radiation exposure of a pregnant worker could result in developmental abnormalities.

  17. Radiative energy balance of Venus based on improved models of the middle and lower atmosphere

    Science.gov (United States)

    Haus, R.; Kappel, D.; Tellmann, S.; Arnold, G.; Piccioni, G.; Drossart, P.; Häusler, B.

    2016-07-01

    The distribution of sources and sinks of radiative energy forces the atmospheric dynamics. The radiative transfer simulation model described by Haus et al. (2015b) is applied to calculate fluxes and temperature change rates in the middle and lower atmosphere of Venus (0-100 km) covering the energetic significant spectral range 0.125-1000 μm. The calculations rely on improved models of atmospheric parameters (temperature profiles, cloud parameters, trace gas abundances) retrieved from Venus Express (VEX) data (mainly VIRTIS-M-IR, but also VeRa and SPICAV/SOIR with respect to temperature results). The earlier observed pronounced sensitivity of the radiative energy balance of Venus to atmospheric parameter variations is confirmed, but present detailed comparative analyses of possible influence quantities ensure unprecedented insights into radiative forcing on Venus by contrast with former studies. Thermal radiation induced atmospheric cooling rates strongly depend on temperature structure and cloud composition, while heating rates are mainly sensitive to insolation conditions and UV absorber distribution. Cooling and heating rate responses to trace gas variations and cloud mode 1 abundance changes are small, but observed variations of cloud mode 2 abundances and altitude profiles reduce cooling at altitudes 65-80 km poleward of 50°S by up to 30% compared to the neglect of cloud parameter changes. Cooling rate variations with local time below 80 km are in the same order of magnitude. Radiative effects of the unknown UV absorber are modeled considering a proxy that is based on a suitable parameterization of optical properties, not on a specific chemical composition, and that is independent of the used cloud model. The UV absorber doubles equatorial heating near 68 km. Global average radiative equilibrium at the top of atmosphere (TOA) is characterized by the net flux balance of 156 W/m2, the Bond albedo of 0.76, and the effective planetary emission temperature of 228

  18. Radiation Risk Associated with Low Doses of Ionizing Radiation: Irrational Fear or Real Danger

    International Nuclear Information System (INIS)

    The established worldwide practice of protecting people from radiation based on the assessments of radiation risk received in the researches carried out earlier costs hundreds of billions of dollars a year to implement. In the opinion of the well-known experts, the maintenance of the existing radiation protection regulations or moreover acceptance of more tough regulations can influence the development of nuclear power engineering. The accepted practice of assessment of human health risk from radiation may also significantly affect our perception of threats of radiation terrorism. In this work, the critical analysis of publications on the assessment of the effects of small doses of radiation on human health is carried out. In our analysis, we especially emphasize the data on cancer mortality among survivors of the atomic bombing of Hiroshima and Nagasaki who received instantaneous radiation doses of less than 200 mSv including the data on leukemia and solid cancer, as well as epidemiological studies in the regions of India and China with high level of natural radiation. Since the investigations of radiation risk is a base for formulating modern radiation protection regulations, their reliability and validity are of great importance. As follows from the analysis, the subsequent, during three decades, toughening of radiation protection regulations has already led to exceedingly prohibitive standards and impractical recommendations the science-based validity of which can cause serious doubts. Now, a number of world-wide known scientists and authoritative international organizations call for revision of these standards and of the radiation safety concept itself. (author)

  19. Radiation Risk and Possible Consequences for Ukrainian Population

    Energy Technology Data Exchange (ETDEWEB)

    Pivovarov, Alexander [Ukrainian State Chemical-Technology Univ., Dnepropetrovsk (Ukraine)

    2006-09-15

    The paper deals with the values of risk related to environmental pollution with radionuclides from the main sources located both on the territory of Ukraine and outside, which affect the Ukrainian population, in the context of long-range outlook. Ratios of risk for stochastic effects occurrence are given per unit of individual or collective dose, as well as for occurrence of fatal cancer, non-fatal cancer or serious hereditary effects. Besides, the paper mentions not only the impact of ionizing radiation, but severe population stress as well, which in certain regions turns into radiophobia. It is shown that for essential decrease of radiation risk in Ukraine, global problems should be solved, first of all, at the governmental level. Whereas a number of issues connected with the Chernobyl catastrophe are at least partially solved, the problems concerning the effects of radon and other radiation-dangerous factors are still to be tackled.

  20. Probabilistic methodology for estimating radiation-induced cancer risk

    International Nuclear Information System (INIS)

    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

  1. Systematic review on physician's knowledge about radiation doses and radiation risks of computed tomography

    International Nuclear Information System (INIS)

    Background: The frequent use of computed tomography is a major cause of the increasing medical radiation exposure of the general population. Consequently, dose reduction and radiation protection is a topic of scientific and public concern. Aim: We evaluated the available literature on physicians' knowledge regarding radiation dosages and risks due to computed tomography. Methods: A systematic review in accordance with the Cochrane and PRISMA statements was performed using eight databases. 3091 references were found. Only primary studies assessing physicians' knowledge about computed tomography were included. Results: 14 relevant articles were identified, all focussing on dose estimations for CT. Overall, the surveys showed moderate to low knowledge among physicians concerning radiation doses and the involved health risks. However, the surveys varied considerably in conduct and quality. For some countries, more than one survey was available. There was no general trend in knowledge in any country except a slight improvement of knowledge on health risks and radiation doses in two consecutive local German surveys. Conclusions: Knowledge gaps concerning radiation doses and associated health risks among physicians are evident from published research. However, knowledge on radiation doses cannot be interpreted as reliable indicator for good medical practice.

  2. Study on technology for minimizing radiation risk

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Ho; Kim, In Gyu; Kim, Jin Kyu; Lee, Kang Suk; Kim, Kug Chan; Chun, Ki Chung

    1997-01-01

    Apoptosis, also called programmed cell death to discriminate it from necrosis, is characterized by : chromatin condensation, apoptotic body formation, fragmentation of DNA into oligonucleosome sized pieces, swelling and progressive cell degradation. We examined morphological and biochemical changes of T-lymphocytes following gamma irradiation exposure. The results are followings. (1) Murine lymphocytes have several characteristics : The irradiated cells undergo morphological and biochemical changes characteristic of apoptosis, causing growth delay. (0.01, 0.1, 1.0 Gy) (2) The onset of DNA fragmentation in cells occurs after one more cell divisions. (3) DNA fragmentation in cells occurs in all irradiated group (0.1, 1.0, 2.0, 4.0 Gy, 24 hours following gamma radiation exposure) (4) Apoptotic bodies were detected by confocal microscope with ease when compared with electron microscope. For the developing technology for minimizing radiation damage, the following experimental works have been done. (1) Establishment of experimental system for pre-screening of radioprotectants - Screening of protective substances using TSH bioindicator - Efficacy test of some radioprotective materials (2) TSH bioindicator system can make a scientific role in screening unknown materials for their possible radioprotective effect. (author). 42 refs., 3 tabs., 9 figs.

  3. Study on technology for minimizing radiation risk

    International Nuclear Information System (INIS)

    Apoptosis, also called programmed cell death to discriminate it from necrosis, is characterized by : chromatin condensation, apoptotic body formation, fragmentation of DNA into oligonucleosome sized pieces, swelling and progressive cell degradation. We examined morphological and biochemical changes of T-lymphocytes following gamma irradiation exposure. The results are followings. 1) Murine lymphocytes have several characteristics : The irradiated cells undergo morphological and biochemical changes characteristic of apoptosis, causing growth delay. (0.01, 0.1, 1.0 Gy) 2) The onset of DNA fragmentation in cells occurs after one more cell divisions. 3) DNA fragmentation in cells occurs in all irradiated group (0.1, 1.0, 2.0, 4.0 Gy, 24 hours following gamma radiation exposure) 4) Apoptotic bodies were detected by confocal microscope with ease when compared with electron microscope. For the developing technology for minimizing radiation damage, the following experimental works have been done. 1) Establishment of experimental system for pre-screening of radioprotectants - Screening of protective substances using TSH bioindicator - Efficacy test of some radioprotective materials 2) TSH bioindicator system can make a scientific role in screening unknown materials for their possible radioprotective effect. (author). 42 refs., 3 tabs., 9 figs

  4. Space Radiation Cancer Risk Projections and Uncertainties - 2010

    Science.gov (United States)

    Cucinotta, Francis A.; Kim, Myung-Hee Y.; Chappell, Lori J.

    2011-01-01

    Uncertainties in estimating health risks from galactic cosmic rays greatly limit space mission lengths and potential risk mitigation evaluations. NASA limits astronaut exposures to a 3% risk of exposure-induced death and protects against uncertainties using an assessment of 95% confidence intervals in the projection model. Revisions to this model for lifetime cancer risks from space radiation and new estimates of model uncertainties are described here. We review models of space environments and transport code predictions of organ exposures, and characterize uncertainties in these descriptions. We summarize recent analysis of low linear energy transfer radio-epidemiology data, including revision to Japanese A-bomb survivor dosimetry, longer follow-up of exposed cohorts, and reassessments of dose and dose-rate reduction effectiveness factors. We compare these projections and uncertainties with earlier estimates. Current understanding of radiation quality effects and recent data on factors of relative biological effectiveness and particle track structure are reviewed. Recent radiobiology experiment results provide new information on solid cancer and leukemia risks from heavy ions. We also consider deviations from the paradigm of linearity at low doses of heavy ions motivated by non-targeted effects models. New findings and knowledge are used to revise the NASA risk projection model for space radiation cancer risks.

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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

  7. Radiation Dose Risk and Diagnostic Benefit in Imaging Investigations

    CERN Document Server

    Dobrescu, Lidia

    2015-01-01

    The paper presents many facets of medical imaging investigations radiological risks. The total volume of prescribed medical investigations proves a serious lack in monitoring and tracking of the cumulative radiation doses in many health services. Modern radiological investigations equipment is continuously reducing the total dose of radiation due to improved technologies, so a decrease in per caput dose can be noticed, but the increasing number of investigations has determined a net increase of the annual collective dose. High doses of radiation are cumulated from Computed Tomography investigations. An integrated system for radiation safety of the patients investigated by radiological imaging methods, based on smart cards and Public Key Infrastructure allow radiation absorbed dose data storage.

  8. A review of radiation risk estimates

    International Nuclear Information System (INIS)

    Three authoritative reports (UNSCEAR-1988, BEIR-V-1990, and ICRP-1990 Recommendations) on risk estimates have been reviewed and compared to previous risk estimates published by the same organizations. The ICRP now uses the term 'probability' in place of the term 'risk'. For fatal cancers, the new ICRP probability estimates are 5.0 x 10-2 Sv-1 for a population of all ages and 4.0 x 10-2 Sv-1 for a population of working age. For serious hereditary effects summarized over all generations, the ICRP probability coefficients are 1.0 x 10-2 Sv-1 for a population of all ages and 0.6 x 10-2 Sv-1 for a population of working age. For prenatal irradiation, at 8 - 15 weeks after conception, there may be a decrease of 30 I.Q. points per Sv and a risk of cancer which may lie in the range of 2 to 10 x 10-2 Sv-1. Based mainly on the new probability estimates the ICRP recommends a limit on effective dose of 20 mSv per year, averaged over 5 years (100 mSv in 5 years) with the further provision that the effective dose should not exceed 50 mSv in any single year. For public exposure the ICRP recommends an annual limit on effective dose of 1 mSv. However, in special circumstances, a higher value of effective dose could be allowed in a single year provided that the average over 5 five years does not exceed 1 mSv per year. Once pregnancy has been declared, the conceptus should be protected by applying a supplementary equivalent dose limit to the surface of the woman's abdomen of 2 mSv for the remainder of the pregnancy and by limiting intakes of radionuclides to about 1/20 of the annual limit on intake. A brief survey of epidemiological studies of workers and the risks from radon and thoron progeny is also included. (110 refs, 29 tabs., 10 figs.)

  9. Role of net radiation on energy balance closure in heterogeneous grasslands

    Directory of Open Access Journals (Sweden)

    C. Shao

    2011-03-01

    Full Text Available Low energy balance closure (EBC at a particular eddy-covariance flux site increased the uncertainties of carbon, water and energy measurements and thus hampered the urgent research of scaling up and modeling analysis through site combinations. A series of manipulative experiments were conducted in this study to explore the role of net radiation (Rn in the EBC in relation to spatial variability of vegetation characteristics, source area, sensor type, and dome condition in the Inner Mongolian grassland of Northern China. At all three sites, the daytime peak residual fluxes of EBC were consistently about 100 W m−2 regardless of radiometers (i.e., REBS Q7.1 or CNR1. The spatial variability in net radiation was 19 W m−2 (5% of Rn during the day and 7 W m−2 (16% at night, with an average of 13 W m−2 (11% from eight plot measurements across the three sites. Net radiation results were affected more by measurement source area in unclipped heterogeneous system than in clipped homogeneous vegetation. Large area measurement significantly (P<0.0001 increased by 9 W m−2 during the day and decreased by 4 W m−2 at night in unclipped treatments. With an increase in clipping intensity, net radiation decreased by 25 W m−2 (6% of Rn at midday and 81 MJ m−2 (6% during a growing season with heavier regular clipping than that in unclipped treatments. Additional effort in EBC between 9:00 and 15:00 LT is needed for future research because of high variation. Using this method, the EBC difference derived from the two types of net radiometers was only 6 W m−2. Results from Q7.1 with new domes were higher during the day but lower at night than those with used domes. Overall, the inclusion of the uncertainty in available energy accounted for 60% of the 100 W m−2 shortfalls in the lack

  10. A Mechanism of Solar Variability Effect on Radiative Balance of the Earth Atmosphere

    Institute of Scientific and Technical Information of China (English)

    G. A. Zherebtsov; V.A. Kovalenko; S.I. Molodykh

    2005-01-01

    Possible mechanisms of solar-climatic connections, which may be of importance as over short and long time intervals, are discussed. The variations of energetic balance of Earth's climatic system for the last fifty years are estimated. It is ascertained that the disbalance between the flux of solar energy that comes to the Earth and radiates to space is of 0.1% for the last ten years. The suggested mechanism makes it possible to explain not only the observed variation of the enthalpy of the Earth's climatic system for the period 1910-1980, but also the climate anomalies during last thousand years: the climate optimum in 12 century, and"small glacial period" in 16-17 centuries.

  11. Patients with autosomal dominant spinocerebellar ataxia have more risk of falls, important balance impairment, and decreased ability to function

    Directory of Open Access Journals (Sweden)

    Carolina Yuri P. Aizawa

    2013-08-01

    Full Text Available OBJECTIVES: To assess balance and ability to function in patients with spinocerebellar ataxia. METHODS: A total of 44 patients with different spinocerebellar ataxia types 1, 2, 3, and 6 were evaluated using the Tinetti balance and gait assessment and the functional independence measure. The scale for the assessment and rating of ataxia and the international cooperative ataxia rating scale were used to evaluate disease severity. RESULTS: Most patients showed significant risk of falls. The balance scores were significantly different in spinocerebellar ataxia types. A significant positive correlation between balance and disease severity was found. CONCLUSION: Patients with spinocerebellar ataxia have important balance impairment and risk of falls that influence the ability to function such as self-care, transfers, and locomotion. Furthermore, the more severe ataxia is, the more compromised are postural balance, risk of falls, and ability to function.

  12. Understanding radiation and risk: the importance of primary and secondary education

    Energy Technology Data Exchange (ETDEWEB)

    Tada, Junichiro [Japan Synchrotron Radiation Research Institute (SPring-8), Mikaduki, Hyogo (Japan)

    1999-09-01

    In Japan's primary and secondary schools, radiation and radioactivity are taught as part of the curriculum dealing with social science subjects. Students learn much about the hazardous features of radiation, but lack the scientific understanding necessary to build a more balanced picture. Although the same point applies to education covering the harmful effects of volcanic eruptions, earthquakes, electrical storms and so on, public understanding of these events is relatively high and students are generally able to make informed judgments about the risks involved. By contrast, their limited understanding of radiation often contributes to fears that it is evil or even supernatural. To correct this distortion, it is important that primary and secondary education includes a scientific explanation of radiation. Like heat and light, radiation is fundamental to the history of the universe; and scientific education programs should give appropriate emphasis to this important subject. Students would then be able to make more objective judgments about the useful and hazardous aspects of radiation. (author)

  13. Test models for estimating radiation balance in different scales for Jaboticabal, SP

    Directory of Open Access Journals (Sweden)

    Valquíria de Alencar Beserra

    2012-12-01

    Full Text Available The net radiation (Rn in agroecosystems is the amount of energy that is available in the environment to heating processes of living organisms, air and soil; perspiration of animals and plants; photosynthesis and water evaporation. The Rn defines the type of climate and weather conditions prevailing in a region affecting the availability and thermal water, the fundamental understanding of genotype-environment, which ultimately determine the productivity of the agricultural system. Rn usually is used in models of weather and climate studies. The sustainability and economic viability of zootechnical activity is dependent on the positive interaction between animal and environment. Environmental factors such as water, shading, thermal exchanges sensible heat (conduction, convection and radiation skin and latent heat losses (evaporation and transpiration, conditioned by Rn, must be managed to provide the best results. The present study was conducted to develop and test models for accurate and precise radiation balance on the scales daily, monthly and seasonal ten-day for Jaboticabal - SP, due to the importance of estimates of net radiation for agricultural activities. We used daily meteorological data from weather station located in Jaboticabal, SP (coordinates: 21 ° 14'05 "South, 48 ° 17'09" West, 615m altitude at Universidade Estadual Paulista "Júlio Mesquita Filho" - FCAV/UNESP in a situation of default grass "Bahiagrass" during the period 20/08/2005 to 20/01/2012. The data used were the maximum temperature (Tmax, minimum (Tmin and mean (TMED; maximum relative humidity (URMáx, minimum (URMín and average (URMéd precipitation (mm, average velocity (m/s, Qo, solar radiation (MJ m-2, sunshine (hour meter (MJ m², soil temperature at two depths (Tsoil2CM, Tsoil5CM and class A pan evaporation (TCA (mm. The measures taken by the balance radiometer were taken as a reference to test other models. The models tested were those reported by NORMAN et al

  14. Space Radiation Cancer Risks and Uncertainties for Mars Missions

    Science.gov (United States)

    Cucinotta, F. A.; Schimmerling, W.; Wilson, J. W.; Peterson, L. E.; Badhwar, G. D.; Saganti, P. B.; Dicello, J. F.

    2001-01-01

    Projecting cancer risks from exposure to space radiation is highly uncertain because of the absence of data for humans and because of the limited radiobiology data available for estimating late effects from the high-energy and charge (HZE) ions present in the galactic cosmic rays (GCR). Cancer risk projections involve many biological and physical factors, each of which has a differential range of uncertainty due to the lack of data and knowledge. We discuss an uncertainty assessment within the linear-additivity model using the approach of Monte Carlo sampling from subjective error distributions that represent the lack of knowledge in each factor to quantify the overall uncertainty in risk projections. Calculations are performed using the space radiation environment and transport codes for several Mars mission scenarios. This approach leads to estimates of the uncertainties in cancer risk projections of 400-600% for a Mars mission. The uncertainties in the quality factors are dominant. Using safety standards developed for low-Earth orbit, long-term space missions (>90 days) outside the Earth's magnetic field are currently unacceptable if the confidence levels in risk projections are considered. Because GCR exposures involve multiple particle or delta-ray tracks per cellular array, our results suggest that the shape of the dose response at low dose rates may be an additional uncertainty for estimating space radiation risks.

  15. Adequacy of relative and absolute risk models for lifetime risk estimate of radiation-induced cancer

    International Nuclear Information System (INIS)

    This report examines the applicability of the relative (multiplicative) and absolute (additive) models in predicting lifetime risk of radiation-induced cancer. A review of the epidemiologic literature, and a discussion of the mathematical models of carcinogenesis and their relationship to these models of lifetime risk, are included. Based on the available data, the relative risk model for the estimation of lifetime risk is preferred for non-sex-specific epithelial tumours. However, because of lack of knowledge concerning other determinants of radiation risk and of background incidence rates, considerable uncertainty in modelling lifetime risk still exists. Therefore, it is essential that follow-up of exposed cohorts be continued so that population-based estimates of lifetime risk are available

  16. Radiation effects and risks: overview and a new risk perception index

    International Nuclear Information System (INIS)

    Uncertainty provides opportunities for differences in perception, and radiation risks at low level of exposures involved in few computed tomography scans fall in this category. While there is good agreement among national and international organisations on risk probability of cancer, risk perception has barely been dealt with by these organisations. Risk perception is commonly defined as the subjective judgment that people make about the characteristics and severity of a risk. Severity and latency are important factors in perception. There is a need to connect all these. Leaving risk perception purely as a subjective judgement provides opportunities for people to amplifying risk. The author postulates a risk perception index as severity divided by latency that becomes determining factor for risk perception. It is hoped that this index will bring rationality in risk perception. (authors)

  17. Risk management and radiation protection policies in the Netherlands

    International Nuclear Information System (INIS)

    A risk management policy concerning human mortality was introduced and approved in the Netherlands in 1985. For single technological activities or noxious substances, maximum acceptable levels and negligible levels, respectively, have been defined in terms of the individual risk and the group risk. Individual risks above 10-6/a are considered to be unacceptable, risks between 10-6/a and 10-8/a are considered to be justifiable, whereas risks below 10-8/a are deemed trivial and thus negligible. The limitation of the group risk, being the probability of a disruptive event resulting in more than N simultaneous deaths, is of particular importance for activities which may lead to catastrophic accidents. For man-made hazards with a large societal impact, risk criteria are expressed in terms of complementary cumulative frequency distributions, forming straight lines on a log-log scale of the F-N plot. To deal with risk aversion a slope of -2 for these complementary cumulative frequency distributions is chosen. For example, hazardous incidents in which ten or more persons are killed which have a calculated frequency of 10-5/a are considered unacceptable; a calculated frequency of 100 times lower is considered as negligible. Major accidents may have impact not only on human life but also on environmental quality. Standards limiting the generalized environmental risks are at present in the process of development. The Dutch risk management policy is in several aspects similar, and in others complementary, to the radiation protection principles formulated and elaborated by the International Commission on Radiological Protection. 'Group risk' is a novel concept which has not yet been extensively discussed at the international level. The radiation protection and general environmental protection principles are compared and prospects for harmonization are discussed. (author). 13 refs, 1 fig., 2 tabs

  18. The relevance of radiation induced bystander effects for low dose radiation carcinogenic risk

    International Nuclear Information System (INIS)

    Full text: Where epidemiology studies lack the ability to prescribe radiation doses, customise sample sizes and replicate findings, radiobiology experiments provide greater flexibility to control experimental conditions. This control simplifies the process of answering questions concerning carcinogenic risk after low dose radiation exposures. However, the flexibility requires critical evaluation of radiobiology findings to ensure that the right questions are being asked, the experimental conditions are relevant to human exposure scenarios and that the data are cautiously interpreted in the context of the experimental model. In particular, low dose radiobiology phenomena such as adaptive responses, genomic instability and bystander effects need to be investigated thoroughly, with continual reference to the way these phenomena might occur in the real world. Low dose radiation induced bystander effects are of interest since their occurrence in vivo could complicate the shape of the radiation dose-response curve in the low dose range for a number of biological endpoints with subsequent effects on radiation-induced cancer risk. Conversely, radiation-induced abscopal effects implicate biological consequences of radiation exposure outside irradiated volumes, and complicate the notion of effective dose calculations. Achieving a consensus on the boundaries that distinguish the radiobiology phenomena of bystander and abscopal effects will aid progress towards understanding their relevance to in vivo radiation exposures. A proposed framework for discussing bystander effects and abscopal effects in their appropriate context will be outlined, with a discussion on the future investigation of radiation-induced bystander effects. Such frameworks can assist the integration of results from experimental radiobiology to risk evaluation and management practice. This research was funded by the Low Dose Radiation Research Program, BioI. and Environ. Research, US Dept. of Energy, Grant DE

  19. Radiation and society: a no regret approach to low level radiation risk

    International Nuclear Information System (INIS)

    The linear dose-effect relationship lies at the core of the recommendations of the two major radiation protection organisations. The International Commission on Radiological Protection and the United Nations Scientific Committee on the Effects of Atomic Radiation accept the relationship and the associated non-threshold hypothesis which implies that it is not possible to be at zero risk when exposed to radiation. There is no verifiable scientific evidence for this hypothesis and many argue either that it ignores biological defence mechanisms built up over multiple generations or the possible beneficial effects of low level radiation exposure. This paper briefly addresses the contentious non-threshold hypothesis, considers epidemiological research on the beneficial effects of natural background radiation, and examines the problems of the current regulatory approach to low level radiation risk which foster an exaggerated fear of radiation and can result in severe negative impacts on society. A ''no-regret'' approach is suggested. This could take the form of specifying a reasonable threshold exposure, related perhaps to the natural background radiation exposure, which is considered normal and below which there are no health effects. (UK)

  20. Social and psychological factors under realization of radiation risk

    International Nuclear Information System (INIS)

    In the experiments with mice of Af line, irradiated by gamma-radiation with doses of up to 1.0 Gy and subjected to psycho-emotional effect (the model of 'the provoked aggression') have been investigated the processes of tumour formation. The index of cariogenic efficiency of effects is the number of the induced adenomas in lungs. It has been shown that under separate effect of these factors the frequency of adenomas increases. Under the combined effect the additional number of adenomas per mouse is registered, which exceeds theoretically the expected value assuming additivity of effects, the synergism coefficient was 1.57 (for females). It has been marked that the character of tumour reaction on separate and the combined effect of radiation, as well as the stress-factor has sex distinctions. It has been shown that that real assessment of the radiation risk and the development of the measures system on minimization of medical and biological consequences of the accident should take into account not only the radiation factor, but also a psychological one, especially in those cases when realization of the risk of combined effect of radiation and non-radiation factors can manifest synergism

  1. Surface energy balance, clouds and radiation over Antarctic sea ice during Austral spring

    Science.gov (United States)

    Vancoppenolle, M.; Ackley, S. F.; Perovich, D. K.; Tison, J.-L.

    2009-04-01

    In Sept-Oct 2007, a sea ice drift station, Ice Station Belgica, was established in the Bellingshausen Sea. Over twenty-seven days, measurements of meteorological variables, radiation and surface albedo were performed by combining ship-based and in situ data, in order to assess the surface energy balance. Visual observations of the state of the sky (clear or overcast) were also done. The sampled floe was characterized by thin (0.6m) and medium thick (1.1m) first-year ice and older, second-year ice of greater than 2m mean thickness. Snow cover depth varied from zero cm over the new ice to > 0.8m on the second year ice. The weather at Ice Station Belgica was characterized by typical spring conditions. Synoptic variability was mostly driven by the wind direction, which determines the origin - continental or oceanic - of the air masses. Under northerly winds, warm (from -5 to 0 °C) and wet (relative humidity from 90 to 100%) oceanic air was advected on the floe. Under southerlies, cold (from -20 to -10°C) and dry (70-85 %) continental air was brought on site. In turn, this also determined the state of the sky, with clear (overcast) skies mostly associated to continental (oceanic) weather. The incoming solar radiation was on average 124 W/m², with a trend of 3.5 W/m² over the ice station, while the incoming longwave radiation was on average 227 W/m², with no trend. As expected, the incoming solar radiation shows a marked diurnal cycle, while LW does not. The day-to-day variability in radiation is largely determined by changes in the state of the sky. Broadband surface albedo was measured in situ, using a bidirectional pyranometer, on two sites respectively covered by thin (10-15 cm) and deep (30-40 cm) snow. Both sites were visited every 5 days and albedo was measured on 6 points, spaced by 5 m on an 25-m long "albedo" line. Snow depth was also monitored every meter along the albedo line. The mean albedo is 0.83 ± 0.05. Variations around this mean value are

  2. Uncertainty in modeling dust mass balance and radiative forcing from size parameterization

    Directory of Open Access Journals (Sweden)

    C. Zhao

    2013-07-01

    Full Text Available This study examines the uncertainties in simulating mass balance and radiative forcing of mineral dust due to biases in the dust size parameterization. Simulations are conducted quasi-globally (180° W–180° E and 60° S–70° N using the WRF-Chem model with three different approaches to represent dust size distribution (8-bin, 4-bin, and 3-mode. The biases in the 3-mode or 4-bin approaches against a relatively more accurate 8-bin approach in simulating dust mass balance and radiative forcing are identified. Compared to the 8-bin approach, the 4-bin approach simulates similar but coarser size distributions of dust particles in the atmosphere, while the 3-mode approach retains more fine dust particles but fewer coarse dust particles due to its prescribed σg of each mode. Although the 3-mode approach yields up to 10 days longer dust mass lifetime over the remote oceanic regions than the 8-bin approach, the three size approaches produce similar dust mass lifetime (3.2 days to 3.5 days on quasi-global average, reflecting that the global dust mass lifetime is mainly determined by the dust mass lifetime near the dust source regions. With the same global dust emission (∼6000 Tg yr-1, the 8-bin approach produces a dust mass loading of 39 Tg, while the 4-bin and 3-mode approaches produce 3% (40.2 Tg and 25% (49.1 Tg higher dust mass loading, respectively. The difference in dust mass loading between the 8-bin approach and the 4-bin or 3-mode approaches has large spatial variations, with generally smaller relative difference (-2 and atmospheric warming (0.39∼0.96 W m-2 and in a tremendous difference of a factor of ∼10 in dust TOA cooling (-0.24∼-2.20 W m-2. An uncertainty of a factor of 2 is quantified in dust emission estimation due to the different size parameterizations. This study also highlights the uncertainties in modeling dust mass and number loading, deposition fluxes, and radiative forcing resulting from different size

  3. Radiation-Induced Leukemia at Doses Relevant to Radiation Therapy: Modeling Mechanisms and Estimating Risks

    Science.gov (United States)

    Shuryak, Igor; Sachs, Rainer K.; Hlatky, Lynn; Mark P. Little; Hahnfeldt, Philip; Brenner, David J.

    2006-01-01

    Because many cancer patients are diagnosed earlier and live longer than in the past, second cancers induced by radiation therapy have become a clinically significant issue. An earlier biologically based model that was designed to estimate risks of high-dose radiation induced solid cancers included initiation of stem cells to a premalignant state, inactivation of stem cells at high radiation doses, and proliferation of stem cells during cellular repopulation after inactivation. This earlier model predicted the risks of solid tumors induced by radiation therapy but overestimated the corresponding leukemia risks. Methods: To extend the model to radiation-induced leukemias, we analyzed in addition to cellular initiation, inactivation, and proliferation a repopulation mechanism specific to the hematopoietic system: long-range migration through the blood stream of hematopoietic stem cells (HSCs) from distant locations. Parameters for the model were derived from HSC biologic data in the literature and from leukemia risks among atomic bomb survivors v^ ho were subjected to much lower radiation doses. Results: Proliferating HSCs that migrate from sites distant from the high-dose region include few preleukemic HSCs, thus decreasing the high-dose leukemia risk. The extended model for leukemia provides risk estimates that are consistent with epidemiologic data for leukemia risk associated with radiation therapy over a wide dose range. For example, when applied to an earlier case-control study of 110000 women undergoing radiotherapy for uterine cancer, the model predicted an excess relative risk (ERR) of 1.9 for leukemia among women who received a large inhomogeneous fractionated external beam dose to the bone marrow (mean = 14.9 Gy), consistent with the measured ERR (2.0, 95% confidence interval [CI] = 0.2 to 6.4; from 3.6 cases expected and 11 cases observed). As a corresponding example for brachytherapy, the predicted ERR of 0.80 among women who received an inhomogeneous low

  4. Uncertainties in Projecting Risks of Late Effects from Space Radiation

    Science.gov (United States)

    Cucinotta, F.; Schimmerling, W.; Peterson, L.; Wilson, J.; Saganti, P.; Dicello, J.

    The health risks faced by astronauts from space radiation include cancer, cataracts, hereditary effects, CNS risks, and non - cancer morbidity and mortality risks related to the diseases of the old age. Methods used to project risks in low -Earth orbit are of questionable merit for exploration missions because of the limited radiobiology data and knowledge of galactic cosmic ray (GCR) heavy ions, which causes estimates of the risk of late effects to be highly uncertain. Risk projections involve a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Within the linear-additivity model, we use Monte-Carlo sampling from subjective uncertainty distributions in each factor to obtain a maximum likelihood estimate of the overall uncertainty in risk projections. The resulting methodology is applied to several human space exploration mission scenarios including ISS, lunar station, deep space outpost, and Mar's missions of duration of 360, 660, and 1000 days. The major results are the quantification of the uncertainties in current risk estimates, the identification of the primary factors that dominate risk projection uncertainties, and the development of a method to quantify candidate approaches to reduce uncertainties or mitigate risks. The large uncertainties in GCR risk projections lead to probability distributions of risk that mask any potential risk reduction using the "optimization" of shielding materials or configurations. In contrast, the design of shielding optimization approaches for solar particle events and trapped protons can be made at this time, and promising technologies can be shown to have merit using our approach. The methods used also make it possible to express risk management objectives in terms of quantitative objectives, i.e., number of days in space without exceeding a given risk level within well defined confidence limits

  5. On energy balance and the structure of radiated waves in kinetics of crystalline defects

    Science.gov (United States)

    Sharma, Basant Lal

    2016-11-01

    Traveling waves, with well-known closed form expressions, in the context of the defects kinetics in crystals are excavated further with respect to their inherent structure of oscillatory components. These are associated with, so called, Frenkel-Kontorova model with a piecewise quadratic substrate potential, corresponding to the symmetric as well as asymmetric energy wells of the substrate, displacive phase transitions in bistable chains, and brittle fracture in triangular lattice strips under mode III conditions. The paper demonstrates that the power expended theorem holds so that the sum of rate of working and the rate of total energy flux into a control strip moving steadily with the defect equals the rate of energy sinking into the defect, in the sense of N.F. Mott. In the conservative case of the Frenkel-Kontorova model with asymmetric energy wells, this leads to an alternative expression for the mobility in terms of the energy flux through radiated lattice waves. An application of the same to the case of martensitic phase boundary and a crack, propagating uniformly in bistable chains and triangular lattice strips, respectively, is also provided and the energy release is expressed in terms of the radiated energy flux directly. The equivalence between the well-known expressions and their alternative is established via an elementary identity, which is stated and proved in the paper as the zero lemma. An intimate connection between the three distinct types of defects is, thus, revealed in the framework of energy balance, via a structural similarity between the corresponding variants of the 'zero' lemma containing the information about radiated energy flux. An extension to the dissipative models, in the presence of linear viscous damping, is detailed and analog of the zero lemma is proved. The analysis is relevant to the dynamics of dislocations, brittle cracks, and martensitic phase boundaries, besides possible applications to analogous physical contexts which are

  6. Mechanisms of Enhanced Cell Killing at Low Doses: Implications for Radiation Risk

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Peter J. Johnston; Dr. George D. Wilson

    2003-10-15

    We have shown that cell lethality actually measured after exposure to low-doses of low-LET radiation, is markedly enhanced relative to the cell lethality previously expected by extrapolation of the high-dose cell-killing response. Net cancer risk is a balance between cell transformation and cell kill and such enhanced lethality may more than compensate for transformation at low radiation doses over a least the first 10 cGy of low-LET exposure. This would lead to a non-linear, threshold, dose-risk relationship. Therefore our data imply the possibility that the adverse effects of small radiation doses (<10 cGy) could be overestimated in specific cases. It is now important to research the mechanisms underlying the phenomenon of low-dose hypersensitivity to cell killing, in order to determine whether this can be generalized to safely allow an increase in radiation exposure limits. This would have major cost-reduction implications for the whole EM program.

  7. Ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS)

    International Nuclear Information System (INIS)

    Since July 2015 the study ''ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS) - an international cohort study'' is available. INWORKS comprised data from 300.000 occupational exposed and dosimetric monitored persons from France, USA and UK. The contribution is a critical discussion of this study with respect to the conclusion of a strong evidence of positive associations between protracted low-dose irradiation exposure and leukemia.

  8. Ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS)

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Bernd

    2015-07-01

    Since July 2015 the study ''ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS) - an international cohort study'' is available. INWORKS comprised data from 300.000 occupational exposed and dosimetric monitored persons from France, USA and UK. The contribution is a critical discussion of this study with respect to the conclusion of a strong evidence of positive associations between protracted low-dose irradiation exposure and leukemia.

  9. Probabilistic assessment of radiation risk for astronauts in space missions

    Science.gov (United States)

    Kim, Myung-Hee Y.; De Angelis, Giovanni; Cucinotta, Francis A.

    2011-04-01

    Accurate estimations of the health risks to astronauts due to space radiation exposure are necessary for future lunar and Mars missions. Space radiation consists of solar particle events (SPEs), comprised largely of medium energy protons (less than several hundred MeV); and galactic cosmic rays (GCR), which include high-energy protons and heavy ions. While the frequency distribution of SPEs depends strongly upon the phase within the solar activity cycle, the individual SPE occurrences themselves are random in nature. A solar modulation model has been developed for the temporal characterization of the GCR environment, which is represented by the deceleration potential, ϕ. The risk of radiation exposure to astronauts as well as to hardware from SPEs during extra-vehicular activities (EVAs) or in lightly shielded vehicles is a major concern for radiation protection. To support the probabilistic risk assessment for EVAs, which could be up to 15% of crew time on lunar missions, we estimated the probability of SPE occurrence as a function of solar cycle phase using a non-homogeneous Poisson model [1] to fit the historical database of measurements of protons with energy>30 MeV, Φ30. The resultant organ doses and dose equivalents, as well as effective whole body doses, for acute and cancer risk estimations are analyzed for a conceptual habitat module and for a lunar rover during space missions of defined durations. This probabilistic approach to radiation risk assessment from SPE and GCR is in support of mission design and operational planning for future manned space exploration missions. Internal documentation of NASA Constellation Trade Study (F.A. Cucinotta, personal communication).

  10. Heel spur radiotherapy and radiation carcinogenesis risk estimation

    International Nuclear Information System (INIS)

    Radiotherapy is a nonsurgical alternative therapy of painful heel spur patients. Nonetheless, cancer induction is the most important somatic effect of ionizing radiation. This study was designed to evaluate the carcinogenesis risk factor in benign painful heel spur patients treated by radiotherapy. Between 1974 and 1999, a total of 20 patients received mean 8.16 Gy total irradiation dose in two fractions. Thermoluminescent dosimeters (TLD100) were placed on multiple phantom sites in vivo within the irradiated volume to verify irradiation accuracy and carcinogenesis risk factor calculation. The 20 still-alive patients, who had a minimum 5-year and maximum 29-year follow-up (mean 11.9 years), have been evaluated by carcinogenic radiation risk factor on the basis of tissue weighting factors as defined by the International Commission on Radiological Protection Publication 60. Reasonable pain relief has been obtained in all 20 patients. The calculated mean carcinogenesis risk factor is 1.3% for radiation portals in the whole group, and no secondary cancer has been clinically observed. Radiotherapy is an effective treatment modality for relieving pain in calcaneal spur patients. The estimated secondary cancer risk factor for irradiation of this benign lesion is not as high as was feared. (author)

  11. A new perspective on radiation risk communication in Fukushima, Japan

    International Nuclear Information System (INIS)

    The March 11, 2011 cascading disasters of the historic earthquake, unprecedented tsunami, and subsequent radioactive substances release from the Fukushima Daiichi nuclear power plant have shocked the world. But the specter of radiation exposure has complicated the earthquake and tsunami disaster aid activities. Herein is a personal commentary on the current status of the risk communication activities within the disaster populations in Fukushima prefecture. A literature review of the current scientific literature was performed focusing on risk communication within the Fukushima region during the disaster recovery phase. I have limited my commentary to only the 5 most relevant of the publications which focus exclusively on the issue of risk communication and the problems which have generated the urgency to improve risk communication. There were several themes which were consistently identified across the articles and echo some of the personal observations of the many types of responses which victims are now demonstrating: fear, anger, distrust, denial, confusion, uncertainty, ambivalence, and hyperbole stood out regarding their varied responses to the current radiological situation and, regarding the government role in risk communication, corruption and lack of transparency. Two recommendations for helping to address these issues in risk communication are the inclusion of a community intermediary and great use of community engagement in the disaster recovery process. Improved risk communication, perhaps using established guidelines and including both community intermediaries and improved community engagement, may prove useful within the radiation affected populations of Japan. (author)

  12. Risk of breast cancer following low-dose radiation exposure

    International Nuclear Information System (INIS)

    Risk of breast cancer following radiation exposure was studied, based on surveys of tuberculosis patients who had multiple fluoroscopic examinations of the chest, mastitis patients given radiotherapy, and atomic bomb survivors. Analysis suggests that the risk is greatest for persons exposed as adolescents, although exposure at all ages carries some risk. The dose-response relationship was consistent with linearity in all studies. Direct evidence of radiation risk at doses under 0.5 Gy (50 rad) is apparent among A-bomb survivors. Fractionation does not appear to diminish risk, nor does time since exposure (even after 45 years of observation). The interval between exposure and the clinical appearance of radiogenic breast cancer may be mediated by hormonal or other age-related factors but is unrelated to dose. Age-specific absolute risk estimtes for all studies are remarkably similar. The best estimate of risk among American women exposed after age 20 is 6.6 excess cancers/104 WY-Gy

  13. Perception of risk for older people living with a mental illness: Balancing uncertainty.

    Science.gov (United States)

    Clancy, Leonie; Happell, Brenda; Moxham, Lorna

    2015-12-01

    Risk is commonly defined as a negative threat which needs to be controlled and mitigated; as a concept, it takes high priority in contemporary mental health services. Health-care organizations and clinicians are now required to use levels of risk as a benchmark for clinical decision-making. However, perceptions of risk change according to the lens through which it is viewed. A qualitative, exploratory research study was undertaken in an aged persons' mental health programme in Victoria, Australia, to explore the notion of risk from the multiple perspectives of service providers and consumers. Data were obtained through in-depth interviews, and analysis was based on the framework of Ritchie and Spencer. Balancing uncertainty emerged as a major theme, and comprised two subthemes: (i) complexity of risk from the perspective of providers of services; and (ii) complexity of safety from the perspectives of recipients of services. These differences emphasize a significant disjuncture between perceptions of risk and the potential for the individual needs and concerns of consumers to be subsumed under broader organizational issues. The uncertainty this tension highlights suggests the need to reconceptualize risk, incorporating the views and experiences of all stakeholders, particularly consumers and carers, to enhance recovery-oriented services and facilitate consumer participation within mental health services.

  14. Lack of Effect for Decisional Balance as a Brief Motivational Intervention for At-Risk College Drinkers

    OpenAIRE

    Collins, Susan E.; Carey, Kate B.

    2005-01-01

    This study examined the effects of written and in-person decisional balance exercises on measures of risky drinking. College students determined to be at-risk for alcohol-related problems (N = 131) were randomly assigned to an in-person decisional balance (IDB), a written decisional balance (WDB), or an assessment-only control (C) group. IDB participants met with an interventionist for individual 30-minute discussions of the pros and cons of maintaining versus changing their drinking behavior...

  15. Ionizing radiation and cancer risk: evidence from epidemiology.

    Science.gov (United States)

    Ron, E

    1998-11-01

    Epidemiological studies provide the primary data on the carcinogenic effects of radiation in humans. Much of what is known has come from studies of the atomic bomb survivors, and to a lesser extent from patients receiving radiotherapy. These studies demonstrate that exposure to moderate to high doses of radiation increases the risk of cancer in most organs. For all solid cancers combined, cancers of the thyroid, breast and lung, and leukemia, risk estimates are fairly precise, and associations have been found at relatively low doses (bomb survivors, a linear-quadratic dose response seems to fit the data better than a pure linear model. Radiation does not act entirely in isolation. It can interact with other carcinogens, e.g. tobacco or chemotherapeutic agents, and with host factors such as age at exposure, gender or reproductive history. Interactions with medical interventions or with certain heritable mutations have also been suggested. While the studies of high-dose exposures are essential for understanding the overall biological consequences of radiation exposure, the public is more concerned about the long-term health effects from protracted exposures at low doses. Unfortunately, the inherent limitations of epidemiology make it extremely difficult to directly quantify health risks from these exposures. While most epidemiological data are compatible with linear extrapolations from exposures at high doses or high dose rates, they cannot entirely exclude other possibilities. As the field of epidemiology advances, understanding more about the health effects of prolonged and low-dose exposures will be the next challenge. PMID:9806607

  16. Communicating Radiation Risk to the Population of Fukushima.

    Science.gov (United States)

    Takamura, N; Taira, Y; Yoshida, K; Nakashima-Hashiguchi, K; Orita, M; Yamashita, S

    2016-09-01

    Radiological specialists from Nagasaki University have served on the medical relief team organized at Fukushima Medical University Hospital (Fukushima City) ever since the accident at the Fukushima Dai-ichi nuclear power plant. Furthermore, we have conducted the radiation crisis communication efforts by spreading correct information on the health effects of radiation as 'advisors on radiation health risk control'. Nagasaki University has been assisting the reconstruction efforts of Kawauchi Village in Fukushima Prefecture, which was the first village to declare that residents could safely return to their homes because radiation doses were found to be at comparatively low levels. In April 2013, Nagasaki University and the Kawauchi government office concluded an agreement concerning comprehensive cooperation toward reconstruction of the village. As a result, we established a satellite facility of the university in the village. In conclusion, training of specialists who can take responsibility for long-term risk communication regarding the health effects of radiation as well as crisis communication in the initial phase of the accident is an essential component of all such recovery efforts. Establishment of a training system for such specialists will be very important both for Japan and other countries worldwide.

  17. Radiation Dose-Response Relationships and Risk Assessment

    International Nuclear Information System (INIS)

    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

  18. Urban pollution by electromagnetic radiation. What risk for human health?

    International Nuclear Information System (INIS)

    Power lines, domestic appliances, radios, TV sets, cell-phones, radar, etc., they are all instruments which, entering our everyday life, cause electromagnetic pollution. The risks for human health as a consequence of being exposed to this kind of radiation haven't been clearly ascertained yet, even if there is proof of the connection between the onset of some tumoral forms and exposure to electromagnetic fields. Many countries, among which Italy, are tackling the problem of safety distances, necessary to reduce exposure to non-ionising radiation, by issuing bills suitable for human health protection

  19. Total Risk Management for Low Dose Radiation Exposures

    International Nuclear Information System (INIS)

    Our civilization is witnessing about century of nuclear age mixed with enormous promises and cataclysmic threats. Nuclear energy seems to encapsulate both potential for pure good and evil or at least we humans are able to perceive that. These images are continuously with us and they are both helping and distracting from making best of nuclear potentials for civilization. Today with nuclear use significantly present and with huge potential to further improve our life with energy and medical use it is of enormous importance to try to have calmed, rational, and objective view on potential risks and certain benefits. Because all use of nuclear energy proved that their immediate risks are negligible (i.e., Three Mile Island and Fukushima) or much smaller than from the other alternatives (i.e., Chernobyl) it seems that the most important issue is the amount of risk from the long term effects to people from exposure to small doses of radiation. A similar issue is present in the increased use of modern computational tomography and other radiation sources use in medicine for examination and therapy. Finally, extreme natural exposures are third such potential risk sources. Definition of low doses varies depending on the way of delivery (i.e., single, multiple or continuous exposures), and for this paper usual dose of 100 mSv is selected as yearly upper amount. There are three very different scientifically supported views on the potential risks from the low doses exposure. The most conservative theory is that all radiation is harmful, and even small increments from background levels (i.e., 2-3 mSv) present additional risk. This view is called linear no threshold theory (LNT) and it is accepted as a regulatory conservative simple approach which guarantees safety. Risk is derived from the extrapolation of the measured effects of high levels of radiation. Opposite theory to LNT is hormesis which assumes that in fact small doses of radiation are helpful and they are improving our

  20. Human exposure to high natural background radiation: what can it teach us about radiation risks?

    Energy Technology Data Exchange (ETDEWEB)

    Hendry, Jolyon H; Sohrabi, Mehdi; Burkart, Werner [Department of Nuclear Sciences and Applications, International Atomic Energy Agency, Vienna (Austria); Simon, Steven L [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD (United States); Wojcik, Andrzej [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Cardis, Elisabeth [Centre for Research in Environmental Epidemiology (CREAL), Municipal Institute of Medical Research (IMIM-Hospital del Mar) and CIBER Epidemiologia y Salud Publica - CIBERESP, Barcelona (Spain); Laurier, Dominique; Tirmarche, Margot [Radiobiology and Epidemiology Department, Radiological and Human Health Division, Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-Roses (France); Hayata, Isamu [National Institute of Radiological Sciences, Chiba (Japan)], E-mail: jhendry2002uk@yahoo.com

    2009-06-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of {sup 222}Rn and its radioactive progeny. However, despite extensive knowledge of radiation risks gained through epidemiologic investigations and mechanistic considerations, the health effects of chronic low-level radiation exposure are still poorly understood. The present paper reviews the possible contribution of studies of populations living in high natural background radiation (HNBR) areas (Guarapari, Brazil; Kerala, India; Ramsar, Iran; Yangjiang, China), including radon-prone areas, to low dose risk estimation. Much of the direct information about risk related to HNBR comes from case-control studies of radon and lung cancer, which provide convincing evidence of an association between long-term protracted radiation exposures in the general population and disease incidence. The success of these studies is mainly due to the careful organ dose reconstruction (with relatively high doses to the lung), and to the fact that large-scale collaborative studies have been conducted to maximise the statistical power and to ensure the systematic collection of information on potential confounding factors. In contrast, studies in other (non-radon) HNBR areas have provided little information, relying mainly on ecological designs and very rough effective dose categorisations. Recent steps taken in China and India to establish cohorts for follow-up and to conduct nested case-control studies may provide useful information about risks in the future, provided that careful organ dose reconstruction is possible and information is collected on potential confounding factors.

  1. Chromospheric and Coronal Structure of Polar Plumes. 1; Magnetic Structure and Radiative Energy Balance

    Science.gov (United States)

    Allen, Maxwell J.; Oluseyi, Hakeem M.; Walker, Arthur B. C.; Hoover, Richard B.; Barbee, Troy W., Jr.

    1997-01-01

    The Multi-Spectral Solar Telescope Array (MSSTA), a rocket-borne solar observatory, was successfully launched from White Sands Missile Range, New Mexico, on May 13, 1991 at 19:05 UT. The telescope systems onboard the MSSTA obtained several full disk solar images in narrow bandpasses centered around strong soft X-ray, EUV, and FUV emission lines. Each telescope was designed to be sensitive to the coronal plasmas at a particular temperature, for seven temperatures ranging from 20,000 K to 4,000,000 K. We report here on the images obtained during the initial flight of the MSSTA, and on the chromospheric and coronal structure of polar plumes observed over both poles of the Sun. We have also co-aligned the MSSTA images with Kitt Peak magnetograms taken on the same day. We are able to positively identify the magnetic structures underlying the polar plumes we analyze as unipolar. We discuss the plume observations and present a radiative energy balance model derived from them.

  2. Preventing risk and promoting resilience in radiation health.

    Science.gov (United States)

    Kurth, Margaret H; Linkov, Igor

    2016-10-01

    Because risk assessment is fundamentally deficient in the face of unknown or unforeseeable events and disasters such as occurred in 2011 at the Fukushima Daiichi Nuclear Power Station in Japan, resilience thinking, which focuses on the ability of both natural and human-made systems to prepare for, absorb, and recover from an adverse event and to adapt to new conditions is an important additional consideration in decision making. Radiation contamination is an impediment to most critical functions of a community; resilience planning considers how those critical functions will be maintained in the event that radiation contamination does occur. Therefore, planning should begin with resilience-based thinking and should be complemented with risk assessment-based tools. Integr Environ Assess Manag 2016;12:677-679. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. PMID:27447754

  3. Balancing risks and benefits fairly across generations: cost/benefit considerations

    International Nuclear Information System (INIS)

    This paper has been prepared by the OECD Nuclear Energy Agency Workshop on the environmental and ethical aspects of long-lived radioactive waste disposal. The workshop is intended as a step toward preparation of a collective opinion on deep geological storage of nuclear waste. As requested, this paper answers to the following specific questions : 1) Discounting of costs with time is a widely applied technique in the evaluation of the impact of economic and industrial decisions. Could or should discounting of long-term health risks due to radioactive waste disposal be envisaged? 2) Is it possible to assess what is passed on to future generations in terms of health risks, other detriments and possible benefits of all sorts, directly or indirectly? Should such an assessment be applied generically to human activities in a broad sense or should it concern only waste disposal issues? 3) How can the immediate needs of the current generations for example for energy generation or public health protection be balanced with inter generational equity requirements in the very long term? 4) Are resources devoted to assuring safety of radioactive waste disposal appropriately balanced with risks given that these resources could be applied to other societal goals? 5) Is it preferable to take all physical actions today to minimize any bequest of liabilities for waste management actions to future generations. If not how should financial assets be set aside to meet the liabilities? 6) What guidelines and principles should we follow to balance these risks? Does the proposition that we should not expose future generations to a risk that is not acceptable today appropriately address this issue? 7) Should measures of risk acceptability be considered in the context of individual rights or local rights or the collective rights of the population? 8) What measures are necessary in the siting of repositories to assure that disadvantaged populations do not bear disproportionate burdens? 9) Is

  4. Estimation of radiation risk for astronauts on the Moon

    Science.gov (United States)

    Kuznetsov, N. V.; Nymmik, R. A.; Panasyuk, M. I.; Denisov, A. N.; Sobolevsky, N. M.

    2012-05-01

    The problem of estimating the risk of radiation for humans on the Moon is discussed, taking into account the probabilistic nature of occurrence of solar particle events. Calculations of the expected values of tissue-averaged equivalent dose rates, which are created by galactic and solar cosmic-ray particle fluxes on the lunar surface behind shielding, are made for different durations of lunar missions.

  5. Risk analysis guideline for working with radiation; Leidraad risicoanalyse stralingstoepassingen

    Energy Technology Data Exchange (ETDEWEB)

    Bader, S.

    2010-11-15

    The RIVM has developed a guideline for carrying out ionizing radiation risk analyses. Dutch law requires that radiation risk analyses be carried out, but the Dutch Labour Inspectorate has signalled that compliance is low, primarily because many health physicists lack the necessary knowledge. Noncompliance is a reason for concern, as the risk analysis provides the basis for a proper understanding of the risks of working with radiation. Worker safety is enhanced when the guideline is followed. Dutch law dictates that a risk analysis must be carried out before any individual starts working with radiation. Examples of activities falling under the auspices of this law are the detection of welding defects in gas pipes and the taking of X-rays by veterinarians. The guideline, which was commissioned by the Dutch Ministry of Social Affairs and Employment, is a roadmap in which the most important steps for performing a risk analysis are described. Those responsible for radiation worker safety are expected to modify and apply these guidelines to the specific working conditions of their respective professional groups. [Dutch] Het RIVM heeft een leidraad ontwikkeld waarmee een risicoanalyse kan worden uitgevoerd voor het werken met ioniserende straling. Aanleiding is een signaal van de Arbeidsinspectie dat deze risicoanalyses die bij wet verplicht zijn, te weinig worden opgesteld. Dat komt doordat stralingsdeskundigen vaak niet weten hoe ze zoiets aan moeten pakken. Dit is zorgelijk, omdat de risicoanalyse ten grondslag ligt aan een goed begrip van de risico's van het werken met straling. Gebruik van de leidraad draagt bij aan een betere veiligheid van werknemers. De Nederlandse wet verplicht ondernemers om voorafgaand aan een handeling met ioniserende straling een risicoanalyse uit te laten voeren. Enkele voorbeelden van dat soort handelingen zijn de controle van lasnaden in gasleidingen met gammabronnen en het maken van een rontgenfoto door een dierenarts. De leidraad

  6. Understanding the risk coming from the radiation exposure

    International Nuclear Information System (INIS)

    From 1972, the National Academy has published a series of reports on the biological effects of ionizing radiation (BEIR) in relation to the health effects of the low level radiation. The Environmental Protection Agency, the Department of Energy and the Academy of Sciences of US, began in 1996 the first phase of the BEIR VII report about the health risks associated to the exposure to low level ionizing radiation. The purpose of the first phase of the study is to revise the literature and to decide if enough novel information existed to guarantee the complete study. The National Academies concluded that enough information existed with an appropriate time to carry out the reanalysis. Among the conclusions of BEIR VII are that the current scientific evidence is concordant with the hypothesis of the existence of a linear model without threshold (LSU) in the dose-response relationship among the exposure to ionizing radiation and the cancer development in humans. This implies that very low dose even has the potential of causing deleterious effects in the health, although the risk to low dose is very small. (Author)

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

    OpenAIRE

    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...

  8. The functional assessment Berg Balance Scale is better capable of estimating fall risk in the elderly than the posturographic Balance Stability System

    Directory of Open Access Journals (Sweden)

    Vanessa Vieira Pereira

    2013-01-01

    Full Text Available The purpose of this study was to verify which instrument better identifies recurrent falls in the elderly. Ninety-eight old people, with an average age of 80±4 years, were submitted to an assessment of balance and fall risk by means of the Berg Balance Scale (BBS and the posturographic Balance Stability System (BSS. The BBS was correlated with the BSS (r=-0.27; p=0.008, age (r=-0.38; p<0.001 and number of falls (r=-0.25; p=0.013 and the analysis of logistical regression showed that the elderly classified with fall risk on the BBS presented 2.5 (95%CI 1.08-5.78 more chance of identifying who had two falls or more over the last year. The BBS identified that the greater the age the worse the functional balance and demonstrated a greater capacity to identify falls risk suffered over the last year when compared with the BSS.

  9. Decommissioning and material recycling. Radiation risk management issues

    Energy Technology Data Exchange (ETDEWEB)

    Dodd, D.H.

    1996-09-01

    Once nuclear fuel cycle facilities have permanently stopped operations they have to be decommissioned. The decommissioning of a nuclear facility involves the surveillance and dismantling of the facility systems and buildings, the management of the materials resulting from the dismantling activities and the release of the site for further use. The management of radiation risks associated with these activities plays an important role in the decommissioning process. Existing legislation covers many aspects of the decommissioning process. However, in most countries with nuclear power programmes legislation with respect to decommissioning is incomplete. In particular this is true in the Netherlands, where government policy with respect to decommissioning is still in development. Therefore a study was performed to obtain an overview of the radiation risk management issues associated with decommissioning and the status of the relevant legislation. This report describes the results of that study. It is concluded that future work at the Netherlands Energy Research Foundation on decommissioning and radiation risk management issues should concentrate on surveillance and dismantling activities and on criteria for site release. (orig.).

  10. Decommissioning and material recycling. Radiation risk management issues

    International Nuclear Information System (INIS)

    Once nuclear fuel cycle facilities have permanently stopped operations they have to be decommissioned. The decommissioning of a nuclear facility involves the surveillance and dismantling of the facility systems and buildings, the management of the materials resulting from the dismantling activities and the release of the site for further use. The management of radiation risks associated with these activities plays an important role in the decommissioning process. Existing legislation covers many aspects of the decommissioning process. However, in most countries with nuclear power programmes legislation with respect to decommissioning is incomplete. In particular this is true in the Netherlands, where government policy with respect to decommissioning is still in development. Therefore a study was performed to obtain an overview of the radiation risk management issues associated with decommissioning and the status of the relevant legislation. This report describes the results of that study. It is concluded that future work at the Netherlands Energy Research Foundation on decommissioning and radiation risk management issues should concentrate on surveillance and dismantling activities and on criteria for site release. (orig.)

  11. Solid cancer risks from radiation exposure for the Australian population

    International Nuclear Information System (INIS)

    Estimates are made of the risks to the Australian population as a function of age and gender for mortality or morbidity for all solid cancers after exposure to radiation. Excess relative risk (ERR) and excess absolute risk (EAR) models are used. The model coefficients are re-evaluated for radiation doses expressed as effective dose using data from the Japanese Life Span Study. Life-table methods are used throughout and the risk measures studied are: the risk of exposure related death, RERD and the risk of exposure related cancer, RERC. Australian life-table data and the age-specific cancer incidence and mortality rates of Australian males and females are taken from recent published tables. No dose and dose-rate effectiveness factor is applied. Sources of uncertainty used to calculate the confidence regions for the estimated risks include the statistical uncertainties of the model parameters and of the extrapolation of the risks beyond the period supported by the epidemiological data. Summary values of the risks are reported as averages of those calculated from the ERR and the EAR models. For males, the mortality risks per sievert range from 14% for 0-9 year age group, 7% at 30-39 years and 4% at 50-59 years. Corresponding values for females are 20%, 10% and 6%. Incidence risks are higher: for males the estimates are 32% for the 0-9 year group, 12% at 30-39 and 5% at 50-59. Corresponding values for females are 56%, 20% and 8%. The 90% confidence regions are about ± 50% of these values. Estimates are given for the risks from CT whole-body scanning or virtual colonoscopy which could be used for cancer screening. If used at 3 year intervals and the effective dose per procedure is 10 mSv, then the RERD for males beginning screening at 40, 50 and 60 years is 0.4%, 0.3% and 0.1%, respectively and for females, 0.6%, 0.4% and 0.2%, respectively. RERD estimates for a 5 year interval between screens are about one-third smaller. Copyright (2003) Australasian College of

  12. Doses of low level ionizing radiation; a misunderstood risk, however unavoidable

    International Nuclear Information System (INIS)

    The treatment given by international organizations and associations to the problems of radiation exposures, and the recommendations and norms for calculating risks of low level radiation are analysed. It is shown that there are not zero risks for nuclear energy, and emphasis is given to the risks of natural radiation from environment. (M.C.K.)

  13. Balancing public health and resource limitations: A role for ethical low-level risk communication

    International Nuclear Information System (INIS)

    Recognition of the pervasiveness of risk in everyday life in modern industrial society has elicited calls for greater efforts to protect individual and public health. Yet, it is increasingly clear that decisions to do so must often be made in the context of significant limits in the amounts of financial resources available for achieving that protection. Achieving risk-free work, residential, and community environments may be so expensive as to render a private business unit uncompetitive or as to divert resources from or prelude commencing with other governmental projects with equal or greater health benefit potential. Ethical low-level risk communication (LLRC) is something risk-generating entities are morally obligated to do. However, such communication also offers important opportunities for such entities to move toward achieving better balances between health and the costs of protecting it. In this paper, the authors elaborate on several features of an ethically ideal LLRC process, focusing on those with aspects they hope are not obvious or common knowledge. In discussing these features, they provide examples of conflicts between health risks and resource limits at the level of the individual private firm, the local community, or the national government, such that LLRC with the feature in question provides an opportunity for mitigating or at least clarifying the conflict in question

  14. Effect of proton pump inhibitors on magnesium balance: is there a link to cardiovascular risk?

    Science.gov (United States)

    Pisani, Laura Francesca; Filippi, Elisabetta; Vavassori, Sara; Munizio, Nadia; Vecchi, Maurizio; Pastorelli, Luca

    2016-03-01

    Magnesium (Mg(2+)) is the second most copious element inside human cells and the fourth most abundant positively charged ion in the human body. It is of central importance for a broad variety of physiological processes, including intracellular signaling, neuronal excitability, muscle contraction, bone formation and enzyme activation. Its overall balance is tightly regulated by the concerted actions of the intestine, bones and kidneys. Disturbance of this balance can have serious consequences. Symptoms of hypomagnesaemia include tetany, seizures and cardiac arrhythmias, whereas hypermagnesaemia may cause cardiovascular and neuromuscular abnormalities. Drugs can interfere with Mg(2+) homoeostasis in several ways, and proton-pump inhibitors (PPIs) have been associated with hypomagnesaemia. A better understanding of the molecular mechanisms underlying the adverse effects of these medications on Mg(2+) balance will isuggest ideas for prevention and treatment, and might provide greater insight into Mg(2+) homoeostasis. This review gives an overview of the influence of PPIs on Mg(2+) homoeostasis and provides some understanding of the underlying physiological mechanisms. Moreover, we will discuss the potential link between PPI-induced changes in Mg(2+) homeostasis, and the reported cardiovascular risk observed in long-term PPI users. PMID:27086964

  15. Cancer risk estimation caused by radiation exposure during endovascular procedure

    Science.gov (United States)

    Kang, Y. H.; Cho, J. H.; Yun, W. S.; Park, K. H.; Kim, H. G.; Kwon, S. M.

    2014-05-01

    The objective of this study was to identify the radiation exposure dose of patients, as well as staff caused by fluoroscopy for C-arm-assisted vascular surgical operation and to estimate carcinogenic risk due to such exposure dose. The study was conducted in 71 patients (53 men and 18 women) who had undergone vascular surgical intervention at the division of vascular surgery in the University Hospital from November of 2011 to April of 2012. It had used a mobile C-arm device and calculated the radiation exposure dose of patient (dose-area product, DAP). Effective dose was measured by attaching optically stimulated luminescence on the radiation protectors of staff who participates in the surgery to measure the radiation exposure dose of staff during the vascular surgical operation. From the study results, DAP value of patients was 308.7 Gy cm2 in average, and the maximum value was 3085 Gy cm2. When converted to the effective dose, the resulted mean was 6.2 m Gy and the maximum effective dose was 61.7 milliSievert (mSv). The effective dose of staff was 3.85 mSv; while the radiation technician was 1.04 mSv, the nurse was 1.31 mSv. All cancer incidences of operator are corresponding to 2355 persons per 100,000 persons, which deemed 1 of 42 persons is likely to have all cancer incidences. In conclusion, the vascular surgeons should keep the radiation protection for patient, staff, and all participants in the intervention in mind as supervisor of fluoroscopy while trying to understand the effects by radiation by themselves to prevent invisible danger during the intervention and to minimize the harm.

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

    OpenAIRE

    Chen Yu-Jen; Chong Ngot-Swan; Chang Hou-Tai; Lin Shih-Chiang; Shueng Pei-Wei; Wang Li-Ying; Hsieh Yen-Ping; Hsieh Chen-Hsi

    2009-01-01

    Abstract 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 or...

  17. Risk estimates for the health effects of alpha radiation

    International Nuclear Information System (INIS)

    This report provides risk estimates for various health effects of alpha radiation. Human and animal data have been used to characterize the shapes of dose-response relations and the effects of various modifying factors, but quantitative risk estimates are based solely on human data: for lung cancer, on miners in the Colorado plateau, Czechoslovakia, Sweden, Ontario and Newfoundland; for bone and head cancers, on radium dial painters and radium-injected patients. Slopes of dose-response relations for lung cancer show a tendency to decrease with increasing dose. Linear extrapolation is unlikely to underestimate the excess risk at low doses by more than a factor of l.5. Under the linear cell-killing model, our best estimate

  18. International study on the risks of occupational exposure to radiation

    International Nuclear Information System (INIS)

    In view of the current lack of statistical power of individual worker studies to estimate cancer risks precisely, the International Agency for Research on Cancer (IARC) held a meeting in 1988 to discuss the possibility of international collaborative analyses based on pooling data from different countries. It was decided to carry out a feasibility study of an international collaborative study of groups of workers who had not been investigated at that time. Following that meeting a 'Study Group' comprising epidemiologists and dosimetry experts from each of the interested countries was set up under IARC coordination. The feasibility study established that, within each of the 12 countries represented, information was available to allow identification of a cohort of radiation workers whose mortality could be studied in relation to occupational dose, both retrospectively and prospectively. The retrospective study would be likely to have sufficient statistical power to rule out risks more than a few times current risk estimates. (Author)

  19. Management of cancer risk from radiation: A model and a standard for handling chemical risks?

    International Nuclear Information System (INIS)

    Sparsely ionizing radiation is the environmental cancer initiator which is at present best characterized with respect to the magnitude of cancer risks associated with exposure. Possibilities of estimating cancer risks from chemicals by expressing chemical doses as radiation-dose equivalents was therefore studied. This approach eliminates most of the difficulties encountered in efforts to estimate risks from experimental data. Particularly, it permits an implicit estimation, which cannot be obtained from animal studies, of the influences of promotive and cocarcinogenic factors in human populations. Chemical doses are monitored by adducts of reactive chemicals or metabolites to proteins and DNA in humans and animals. This method overcomes the low sensitivity and low specificity of disease- epidemiological studies and may be used to detect and identify cancer initiators (mutagens) of exogenous or endogenous origin. The expression of doses in a common unit, that is directly related to risk, facilitates addition of and comparisons of risks. The fact that this unit refers to radiation, a factor that is well-known to the public and to administrators, facilitates realization of the magnitude of risks and the application of the ICRP principles for regulation, particularly with regard to stochastic effects. (author)

  20. Radiation dose and radiation risk to foetuses and newborns during X-ray examinations

    International Nuclear Information System (INIS)

    The purpose of this study is to determine the way in which the demands set by degree 423/2000 by the Ministry of Social Affairs and Health are fulfilled with respect to the most radiosensitive groups, the foetus and the child, by estimating the radiation dose and radiation risk to the foetus from x-ray examinations of an expectant mother's pelvic region, finding out the practice involved in preventing doses to embryos and foetuses and assessing dose practices in cases where an embryo or foetus is or shall be exposed, and by estimating radiation dose and risk due to the radiation received by a new-born being treated in a paediatric intensive care unit. No statistics are available in Finland to indicate how many x-ray examinations of the pelvic region and lower abdomen are made to pregnant patients or to show the dose and risk to the foetus due these examinations. In order to find out the practices in radiological departments concerning the pelvic x-ray examination of fertile woman and the number of foetuses exposed, a questionnaire was sent to all radiation safety officers responsible for the safe use of radiation (n = 290). A total of 173 questionnaires were returned. This study recorded the technique and Dose-Area Product of 118 chest examinations of newborns in paediatric intensive care units. Entrance surface doses and effective doses were calculated separately to each newborn. Based on the patient records, the number of all x-ray examinations during the study was calculated and the effective doses were estimated retrospectively to each child. The radiation risk was estimated both for the foetuses and for the newborns. According to this study, it is rare in Finland to expose a pregnant woman to radiation. On the other hand, with the exception of pelvimetry examinations, there are no compiled statistics concerning the number of pelvic x-ray examinations of a pregnant woman. There was no common practice on how to exclude the possibility of pregnancy. The dose to a

  1. Radiation dose and radiation risk to foetuses and newborns during X-ray examinations

    Energy Technology Data Exchange (ETDEWEB)

    Kettunen, A. [Oulu Univ. (Finland)

    2004-05-01

    The purpose of this study is to determine the way in which the demands set by degree 423/2000 by the Ministry of Social Affairs and Health are fulfilled with respect to the most radiosensitive groups, the foetus and the child, by estimating the radiation dose and radiation risk to the foetus from x-ray examinations of an expectant mother's pelvic region, finding out the practice involved in preventing doses to embryos and foetuses and assessing dose practices in cases where an embryo or foetus is or shall be exposed, and by estimating radiation dose and risk due to the radiation received by a new-born being treated in a paediatric intensive care unit. No statistics are available in Finland to indicate how many x-ray examinations of the pelvic region and lower abdomen are made to pregnant patients or to show the dose and risk to the foetus due these examinations. In order to find out the practices in radiological departments concerning the pelvic x-ray examination of fertile woman and the number of foetuses exposed, a questionnaire was sent to all radiation safety officers responsible for the safe use of radiation (n = 290). A total of 173 questionnaires were returned. This study recorded the technique and Dose-Area Product of 118 chest examinations of newborns in paediatric intensive care units. Entrance surface doses and effective doses were calculated separately to each newborn. Based on the patient records, the number of all x-ray examinations during the study was calculated and the effective doses were estimated retrospectively to each child. The radiation risk was estimated both for the foetuses and for the newborns. According to this study, it is rare in Finland to expose a pregnant woman to radiation. On the other hand, with the exception of pelvimetry examinations, there are no compiled statistics concerning the number of pelvic x-ray examinations of a pregnant woman. There was no common practice on how to exclude the possibility of pregnancy. The dose

  2. Radiation risks of medical imaging: separating fact from fantasy.

    Science.gov (United States)

    Hendee, William R; O'Connor, Michael K

    2012-08-01

    During the past few years, several articles have appeared in the scientific literature that predict thousands of cancers and cancer deaths per year in the U.S. population caused by medical imaging procedures that use ionizing radiation. These predictions are computed by multiplying small and highly speculative risk factors by large populations of patients to yield impressive numbers of "cancer victims." The risk factors are acquired from the Biological Effects of Ionizing Radiation (BEIR) VII report without attention to the caveats about their use presented in the BEIR VII report. The principal data source for the risk factors is the ongoing study of survivors of the Japanese atomic explosions, a population of individuals that is greatly different from patients undergoing imaging procedures. For the purpose of risk estimation, doses to patients are converted to effective doses, even though the International Commission on Radiological Protection warns against the use of effective dose for epidemiologic studies or for estimation of individual risks. To extrapolate cancer incidence to doses of a few millisieverts from data greater than 100 mSv, a linear no-threshold model is used, even though substantial radiobiological and human exposure data imply that it is not an appropriate model. The predictions of cancers and cancer deaths are sensationalized in electronic and print public media, resulting in anxiety and fear about medical imaging among patients and parents. Not infrequently, patients are anxious about a scheduled imaging procedure because of articles they have read in the public media. In some cases, medical imaging examinations may be delayed or deferred as a consequence, resulting in a much greater risk to patients than that associated with imaging examinations. © RSNA, 2012. PMID:22821690

  3. Application of the modified Wheeler cap method for radiation efficiency measurement of balanced electrically small antennas in complex environment

    DEFF Research Database (Denmark)

    Zhang, Jiaying; Pivnenko, Sergey; Breinbjerg, Olav

    2010-01-01

    In this paper, application of a modified Wheeler cap method for the radiation efficiency measurement of balanced electrically small antennas is presented. It is shown that the limitations on the cavity dimension can be overcome and thus measurement in a large cavity is possible. The cavity loss...... is investigated, and a modified radiation efficiency formula that includes the cavity loss is introduced. Moreover, a modification of the technique is proposed that involves the antenna working complex environment inside the Wheeler Cap and thus makes possible measurement of an antenna close to a hand or head...

  4. Scientific uncertainties associated with risk assessment of radiation

    International Nuclear Information System (INIS)

    The proper use and interpretation of data pertaining to biological effects of ionizing radiations is based on a continuous effort to discuss the various assumptions and uncertainties in the process of risk assessment. In this perspective, it has been considered useful by the Committee to review critically the general scientific foundations that constitute the basic framework of data for the evaluation of health effects of radiation. This review is an attempt to identify the main sources of uncertainties, to give, when possible, an order of magnitude for their relative importance, and to clarify the principal interactions between the different steps of the process of risk quantification. The discussion has been restricted to stochastic effects and especially to cancer induction in man: observations at the cellular levels and animal and in vitro experiments have not been considered. The consequences which might result from abandoning the hypothesis of linearity have not been directly examined in this draft, especially in respect to the concept of collective dose. Since another document dealing with 'Dose-response relationships for radiation-induced cancer' is in preparation, an effort has been made to avoid any overlap by making reference to that document whenever necessary

  5. Are passive smoking, air pollution and obesity a greater mortality risk than major radiation incidents?

    Science.gov (United States)

    Smith, Jim T

    2007-01-01

    Background Following a nuclear incident, the communication and perception of radiation risk becomes a (perhaps the) major public health issue. In response to such incidents it is therefore crucial to communicate radiation health risks in the context of other more common environmental and lifestyle risk factors. This study compares the risk of mortality from past radiation exposures (to people who survived the Hiroshima and Nagasaki atomic bombs and those exposed after the Chernobyl accident) with risks arising from air pollution, obesity and passive and active smoking. Methods A comparative assessment of mortality risks from ionising radiation was carried out by estimating radiation risks for realistic exposure scenarios and assessing those risks in comparison with risks from air pollution, obesity and passive and active smoking. Results The mortality risk to populations exposed to radiation from the Chernobyl accident may be no higher than that for other more common risk factors such as air pollution or passive smoking. Radiation exposures experienced by the most exposed group of survivors of Hiroshima and Nagasaki led to an average loss of life expectancy significantly lower than that caused by severe obesity or active smoking. Conclusion Population-averaged risks from exposures following major radiation incidents are clearly significant, but may be no greater than those from other much more common environmental and lifestyle factors. This comparative analysis, whilst highlighting inevitable uncertainties in risk quantification and comparison, helps place the potential consequences of radiation exposures in the context of other public health risks. PMID:17407581

  6. Are passive smoking, air pollution and obesity a greater mortality risk than major radiation incidents?

    Directory of Open Access Journals (Sweden)

    Smith Jim T

    2007-04-01

    Full Text Available Abstract Background Following a nuclear incident, the communication and perception of radiation risk becomes a (perhaps the major public health issue. In response to such incidents it is therefore crucial to communicate radiation health risks in the context of other more common environmental and lifestyle risk factors. This study compares the risk of mortality from past radiation exposures (to people who survived the Hiroshima and Nagasaki atomic bombs and those exposed after the Chernobyl accident with risks arising from air pollution, obesity and passive and active smoking. Methods A comparative assessment of mortality risks from ionising radiation was carried out by estimating radiation risks for realistic exposure scenarios and assessing those risks in comparison with risks from air pollution, obesity and passive and active smoking. Results The mortality risk to populations exposed to radiation from the Chernobyl accident may be no higher than that for other more common risk factors such as air pollution or passive smoking. Radiation exposures experienced by the most exposed group of survivors of Hiroshima and Nagasaki led to an average loss of life expectancy significantly lower than that caused by severe obesity or active smoking. Conclusion Population-averaged risks from exposures following major radiation incidents are clearly significant, but may be no greater than those from other much more common environmental and lifestyle factors. This comparative analysis, whilst highlighting inevitable uncertainties in risk quantification and comparison, helps place the potential consequences of radiation exposures in the context of other public health risks.

  7. Cancer risk from low dose radiation depends directly on the organ mass in a general model of radiation-induced cancer risk.

    Science.gov (United States)

    Lin, Z W

    2014-04-01

    Current methods of evaluating radiation-induced cancer risk depend on the organ dose but not explicitly on extensive quantities such as the organ mass. However, at the same organ dose, one may expect the larger number of cells in a larger organ to lead to a higher cancer risk. Here the author introduces organ- and radiation type-specific cell cancer risk coefficients and obtains analytical relations between cancer risk and the radiation environment, which contains the dependence of cancer risk on organ masses. The excess cancer risk induced by low dose radiation for an organ is shown to be directly proportional to the organ mass. Therefore the total excess risk for all solid cancers depends directly on organ masses and consequently on body weight or size. This method is also being compared with three existing methods of evaluating the radiation-induced cancer risk, and special cases where this formulation matches each method are demonstrated. The results suggest that the direct dependence of cancer risk on organ masses needs to be checked against existing epidemiological data and, if verified, should be included in the methodology for the evaluation of radiation-induced cancer risk, in particular the individual risk. This dependence is also expected to affect the cancer risk transport from one population group to another that is different in organ mass, body weight or height. PMID:24562066

  8. Occurrence, spatiotemporal distribution, mass balance and ecological risks of antibiotics in subtropical shallow Lake Taihu, China.

    Science.gov (United States)

    Zhou, Li-Jun; Wu, Qinglong L; Zhang, Bei-Bei; Zhao, Yong-Gang; Zhao, Bi-Ying

    2016-04-20

    The objective of this study was to evaluate the occurrence, spatiotemporal distribution, mass balance and ecological risks of 43 commonly used human and veterinary antibiotics in both aqueous and sedimentary phases in a large subtropical shallow lake, Lake Taihu. In the aqueous phase, sulfonamides (2.64-344 ng L(-1)), lincomycin (ND to 53.8 ng L(-1)) and florfenicol (0.15-963 ng L(-1)) were the main compounds with high concentrations and detection frequencies. In the sedimentary phase, fluoroquinolones (ND to 174 ng g(-1), dry weight) and tetracyclines (ND to 39.6 ng g(-1), dry weight) were the predominant compounds. Antibiotic concentrations in Lake Taihu were generally lower relative to data documented in previous studies on China and other countries. The composition of antibiotics showed that livestock wastewater might be the main source of antibiotics in Lake Taihu, followed by domestic wastewater. Antibiotics in the lake water showed slight spatial variation in summer and significant spatial variation in winter; whereas, antibiotic concentrations in the sediments varied obviously, with high concentrations found in the sites close to potential pollution sources. Mass balance showed that sediments are an important sink and potential source for fluoroquinolones and tetracyclines. In addition to antibiotics' physicochemical properties, the spatiotemporal distribution of antibiotics in the lake was influenced by both pollution sources and lake hydrodynamics. The environmental risk assessment results showed that sulfamethoxazole could pose high risks on the algae in the aquatic ecosystem, followed by tetracyclines (algae) and fluoroquinolones (bacteria). Overall, our study reveals complex compositions and clear spatiotemporal dynamics in Lake Taihu, which were the consequence of pollution sources and lake hydrodynamics. PMID:27048777

  9. Stochastic Effects in Computational Biology of Space Radiation Cancer Risk

    Science.gov (United States)

    Cucinotta, Francis A.; Pluth, Janis; Harper, Jane; O'Neill, Peter

    2007-01-01

    Estimating risk from space radiation poses important questions on the radiobiology of protons and heavy ions. We are considering systems biology models to study radiation induced repair foci (RIRF) at low doses, in which less than one-track on average transverses the cell, and the subsequent DNA damage processing and signal transduction events. Computational approaches for describing protein regulatory networks coupled to DNA and oxidative damage sites include systems of differential equations, stochastic equations, and Monte-Carlo simulations. We review recent developments in the mathematical description of protein regulatory networks and possible approaches to radiation effects simulation. These include robustness, which states that regulatory networks maintain their functions against external and internal perturbations due to compensating properties of redundancy and molecular feedback controls, and modularity, which leads to general theorems for considering molecules that interact through a regulatory mechanism without exchange of matter leading to a block diagonal reduction of the connecting pathways. Identifying rate-limiting steps, robustness, and modularity in pathways perturbed by radiation damage are shown to be valid techniques for reducing large molecular systems to realistic computer simulations. Other techniques studied are the use of steady-state analysis, and the introduction of composite molecules or rate-constants to represent small collections of reactants. Applications of these techniques to describe spatial and temporal distributions of RIRF and cell populations following low dose irradiation are described.

  10. Radiation and Health Effects and Inferring Radiation Risks from the Fukushima Daiichi Accident. Annex X of Technical Volume 4

    International Nuclear Information System (INIS)

    Anxieties about the risk of harm from radiation are often out of proportion to the actual likelihood of harm. Therefore, in order to deal sensibly with situations involving exposure to radiation, it is important to clarify what is known and what is not known about radiation and health effects. This annex provides a general qualitative overview of what is known about radiation-induced health effects, followed by a more detailed exploration of the quantitative inferences that may be drawn from past analyses of the relationships between radiation exposure and risk

  11. Literature search on risks related to ionizing radiations

    International Nuclear Information System (INIS)

    The authors propose a selection of information sources regarding risks related to ionizing radiations. They present knowledge bases which can be found on different Internet sites belonging to different bodies and agencies (IRSN, CEA, INRS, SFRP, CNRS, Radioprotection Cirkus, EDF) and in different books. They present information sources dealing with radionuclides which can be found in French and international Internet sites and in books, information sources concerning different professional activities and sectors (ASN, IRSN, INRS, medical-professional sheets proposed by the CISME, sheets proposed by the Labour Ministry and other bodies). It presents information sources dealing with radiological incidents, accidents and emergencies, dealing with radioactive wastes, with the legal European and French framework. Some additional tools of general or more detailed information are indicated (CIPR, IAEA, UNSCAR, IRPA, IRSN, SFRP, CEA, CEPN, Radiation Cirkus, books). Ways to get an updated search are indicated for different databases, as well as some practical services

  12. Risk of potential radiation accidental situations at TESLA accelerator installation

    Energy Technology Data Exchange (ETDEWEB)

    Spasic Jokic, Vesna [TESLA Accelerator Installation, Lab. of Physics, VINCA Institute of Nuclear Sciences, Belgrade, Serbia and Montenegro (Serbia); Orlic, Milan [VINCA Institute of Nuclear Sciences, Lab. of radioisotopes, Belgrade, Serbia and Montenegro (Serbia); Djurovic, Branka [Military Medical Academy, Radiation Protection Dept., Belgrade, Serbia and Montenegro (Serbia)

    2006-07-01

    The main aim of this paper is to recognize some of the numerous risks of potential exposure and to quantify requirements and probability of failure of radiation protection system due to design event tree. Nature of design and construction of Tesla Accelerator Installation (T.A.I.) make possibility of potential exposure as a result of proven design and modification, trade off, human error as well as defense in depth. In the case of potential exposure human risk is the result of two random events: first, the occurrence of the event that causes the exposure, and the second, the appearance of a harmful effect. The highest doses during potential exposure at T.A.I. can be received at the entrance to primary beam space (V.I.N.C.Y. cyclotron vault) as well as in space with target for fluorine production, high energy experimental channels, proton therapy channel and channel for neutron researches. Expected values of prompt radiation equivalent dose rate in the cyclotron vault is considerably high, in order of 10 Sv/h. Serious problem deals with such large research installation is a number of workers, as visiting research workers of different educational levels and people in Institute who are not professionally connected with ionizing radiation. They could cause willing or unwilling opening of the cyclotron vault doors. Considering some possible scenarios we assumed that during 7000 working hours per year it is reasonably to expect 300 unsafe entries per year. It can be concluded that safety system should be designed so that probability of failure of radiation protection system has to be less than 1.9 10{sup -6}. (authors)

  13. Assessment of Radiation Risk by Circulating microRNAs

    Science.gov (United States)

    Wang, Jufang

    2016-07-01

    Highly energized particles delivered by galactic cosmic rays as well as solar particle events are one of the most severe detrimental factors to the health of crews during long-term space missions. Researches related to the assessment of radiation risk have been carried out with ground-based accelerator facilities all around the world. Circulating microRNAs (miRNAs) in blood have the advantages of specificity and stability, which could be used as disease biomarkers and potential bio-dosimeters to monitor the radiation risk. Based on this backgroud, circulating miRNAs were isolated from blood after Kunming mice were whole-body exposed to 300MeV/u carbon ion beam which were generated by the Heavy Ion Research Facility in Lanzhou (HIRFL), and the levels of miRNA expression were detected by miRNA PCR array. It was found that more than one hundred of circulating miRNAs were responded to carbon ion irradiation. Among these radiosensitive miRNAs, most of them were closely associated with immune system and hematopoietic system. The miRNA levels changed more than 2-fold were further verified by qRT-PCR analysis following exposure to X rays and iron ion beam. Some miRNAs such as let-7a, miR-34a, miR-223 and miR-150 showed obvious radio-sensitivity and dose-dependent effect, demonstrating that they were potential biomarkers of radiation and could be used as ideal bio-dosimeters. Those findings indicate that with the properties of high radio-sensitivity and time-saving quantification method by standard PCR assay, circulating miRNAs may become potential biomarkers for radiation detection in space exploration.

  14. Balance Sheet Network Analysis of Too-Connected-to-Fail Risk in Global and Domestic Banking Systems

    OpenAIRE

    Jorge A. Chan-Lau

    2010-01-01

    The 2008/9 financial crisis highlighted the importance of evaluating vulnerabilities owing to interconnectedness, or Too-Connected-to-Fail risk, among financial institutions for country monitoring, financial surveillance, investment analysis and risk management purposes. This paper illustrates the use of balance sheet-based network analysis to evaluate interconnectedness risk, under extreme adverse scenarios, in banking systems in mature and emerging market countries, and between individual b...

  15. Risk assessment and management of radiofrequency radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Dabala, Dana [Railways Medical Clinic Cluj-Napoca, Occupational Medicine Department, 16-20 Bilascu Gheorghe St., 400015 Cluj-Napoca (Romania); Surducan, Emanoil; Surducan, Vasile; Neamtu, Camelia [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath St., 400293 Cluj-Napoca (Romania)

    2013-11-13

    Radiofrequency radiation (RFR) industry managers, occupational physicians, security department, and other practitioners must be advised on the basic of biophysics and the health effects of RF electromagnetic fields so as to guide the management of exposure. Information on biophysics of RFR and biological/heath effects is derived from standard texts, literature and clinical experiences. Emergency treatment and ongoing care is outlined, with clinical approach integrating the circumstances of exposure and the patient's symptoms. Experimental risk assessment model in RFR chronic exposure is proposed. Planning for assessment and monitoring exposure, ongoing care, safety measures and work protection are outlining the proper management.

  16. Risk assessment and management of radiofrequency radiation exposure

    Science.gov (United States)

    Dabala, Dana; Surducan, Emanoil; Surducan, Vasile; Neamtu, Camelia

    2013-11-01

    Radiofrequency radiation (RFR) industry managers, occupational physicians, security department, and other practitioners must be advised on the basic of biophysics and the health effects of RF electromagnetic fields so as to guide the management of exposure. Information on biophysics of RFR and biological/heath effects is derived from standard texts, literature and clinical experiences. Emergency treatment and ongoing care is outlined, with clinical approach integrating the circumstances of exposure and the patient's symptoms. Experimental risk assessment model in RFR chronic exposure is proposed. Planning for assessment and monitoring exposure, ongoing care, safety measures and work protection are outlining the proper management.

  17. REDUCING THE IMPACT OF RADIATION FACTORS IN AREAS WITH HIGH LEVEL OF RISK

    Directory of Open Access Journals (Sweden)

    D. A. Zaredinov

    2015-01-01

    Full Text Available The article is devoted to the modern problems of radioecology. The study reveals the problems of radioecological situation in some regions of the Republic of Uzbekistan. The main attention of the authors is paid to the ecologically hazardous objects in the uranium mining industry. The characteristics of wastes from uranium mining and stages of development of the mining industry are described. The historical background of the accumulation of the wastes in dumps, the ore-bearing rocks, and other off-balance ores is given. The practical experience and directions radio-ecological safety are generalized, achieving improvements of the environmental quality in areas with high risk. In conclusion, the authors recommend carrying out some measures to reduce an impact of the radiation factor on human health and to stabilize the radioecological situation at the studied regions.

  18. Evaluation of radiation risk and work practices during cerebral interventions

    International Nuclear Information System (INIS)

    This study was intended to evaluate radiation risk to patients during cerebral interventions and the contribution to this risk from work practices. Thirty nine patients undergoing cerebral interventions in a digital subtraction angiography suite were included in this study. Patients who underwent cerebral interventions were categorised into two groups according to the number of cerebral interventions performed on them, and their effective doses were calculated. The effective dose for patients undergoing a single cerebral intervention (group A) varied from 1.55 to 15.9 mSv and for multiple cerebral interventions (group B) varied from 16.52 to 43.52 mSv. Two patients who underwent multiple cerebral interventions (group B) had alopecia of the irradiated scalp

  19. Risks posed by ionizing radiation and chemo-toxic substances

    International Nuclear Information System (INIS)

    Concern over the risks from exposure to radiation or chemical toxins now appears to be forming an integral part of everyday life for a large percentage of the population. In this volume, attempts have therefore been made to compile well documented information relating to those topics as well as to give insights into relevant interconnections and to elucidate certain terms that are not closely enough defined or even have contradictory uses. In the two introductory reports, the multifarious perceptions of what may constitute a risk are outlined and discussed on a large scale stretching from mathematical to purely intuitive factors. The subsequent contributions focus on individual aspects pertinent to dangers from ionizing rays and chemical toxins and examine their wider implications in terms of social, ethical and psychological influences. Of the ten contributions to this volume two were prepared for individual retrieval. (orig./MG)

  20. Evaluation of radiation risk and work practices during cerebral interventions

    Energy Technology Data Exchange (ETDEWEB)

    Livingstone, Roshan S; Raghuram, L; Korah, Ipeson P; Raj, D Victor [Department of Radiodiagnosis, Christian Medical College, Vellore 632004 (India)

    2003-09-01

    This study was intended to evaluate radiation risk to patients during cerebral interventions and the contribution to this risk from work practices. Thirty nine patients undergoing cerebral interventions in a digital subtraction angiography suite were included in this study. Patients who underwent cerebral interventions were categorised into two groups according to the number of cerebral interventions performed on them, and their effective doses were calculated. The effective dose for patients undergoing a single cerebral intervention (group A) varied from 1.55 to 15.9 mSv and for multiple cerebral interventions (group B) varied from 16.52 to 43.52 mSv. Two patients who underwent multiple cerebral interventions (group B) had alopecia of the irradiated scalp.

  1. Responding to the Marketplace: Workforce Balance and Financial Risk at Academic Health Centers.

    Science.gov (United States)

    Retchin, Sheldon M

    2016-07-01

    Elsewhere in this issue, Welch and Bindman present research demonstrating that academic health centers (AHCs) continue to disproportionately comprise specialists and subspecialist faculty physicians compared with community-based physician groups. This workforce composition has served AHCs well through the years-specialists fuel the clinical engine of the major tertiary and quaternary missions of AHCs, and they also dominate much of the clinical and translational research enterprise. AHCs are not alone-less than one-third of U.S. physicians practice primary care. However, health reform has prompted many health systems to reconsider this configuration. Payers, employers, and policy makers are shifting away from fee-for-service toward value-based care. Large community-based physician groups and their parent health systems appear to be far ahead of AHCs with a more balanced physician workforce. Many are leveraging their emphasis on primary care to participate in population health initiatives, such as accountable care organizations, and some own their own health plans. These approaches largely assume some element of financial risk and require both a more balanced workforce and an infrastructure to accommodate the management of covered lives. It remains to be seen whether AHCs will reconsider their own physician specialty composition to emphasize primary care-and, if they do, whether the traditional academic model, or a more community-based approach, will prevail. PMID:27224298

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

    International Nuclear Information System (INIS)

    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

  3. Risky Business: The Science and Art of Radiation Risk Communication in the High Risk Context of Space Travel

    Science.gov (United States)

    Elgart, Shona Robin; Shavers, Mark; Huff, Janice; Patel, Zarana; Semones, Edward

    2016-01-01

    Successfully communicating the complex risks associated with radiation exposure is a difficult undertaking; communicating those risks within the high-risk context of space travel is uniquely challenging. Since the potential risks of space radiation exposure are not expected to be realized until much later in life, it is hard to draw comparisons between other spaceflight risks such as hypoxia and microgravity-induced bone loss. Additionally, unlike other spaceflight risks, there is currently no established mechanism to mitigate the risks of incurred radiation exposure such as carcinogenesis. Despite these challenges, it is the duty of the Space Radiation Analysis Group (SRAG) at NASA's Johnson Space Center to provide astronauts with the appropriate information to effectively convey the risks associated with exposure to the space radiation environment. To this end, astronauts and their flight surgeons are provided with an annual radiation risk report documenting the astronaut's individual radiation exposures from space travel, medical, and internal radiological procedures throughout the astronaut's career. In an effort to improve this communication and education tool, this paper critically reviews the current report style and explores alternative report styles to define best methods to appropriately communicate risk to astronauts, flight surgeons, and management.

  4. Alpha-risk: a European project on the quantification of risks associated with multiple radiation exposures

    Energy Technology Data Exchange (ETDEWEB)

    Laurier, D.; Monchaux, G.; Tirmarche, M. [Institute for Radiological Protection and Nuclear Safety, 92 - Fontenay aux Roses (France); Darby, S. [Cancer Research UK, Oxford (United Kingdom); Cardis, E. [International Agency for Research on Cancer, 69 - Lyon (France); Binks, K. [Westlakes Scientific Consulti ng Ltd, Moor Row (United Kingdom); Hofmann, W. [Salzburg Univ. (Austria); Muirhead, C. [Health Protection Agency, Chilton (United Kingdom)

    2006-07-01

    The Alpha-Risk research project is being conducted within the Sixth European Framework Programme (EC-FP6, 2005 -2008). It aims to improve the quantification of risks associated with multiple exposures, taking into account the contribution of different radionuclides and external exposure using specific organ dose calculations. The Alpha-Risk Consortium involves 18 partners from 9 countries, and is coordinated by the IRSN. Its composition allows a multidisciplinary collaboration between researchers in epidemiology, dosimetry, statistics, modelling and risk assessment. Alpha-Risk brings together major epidemiological studies in Europe, which are able to evaluate long-term health effects of internal exposure from radionuclides. It includes large size cohort and case-control studies, with accurate registration of individual annual exposures: uranium miner studies, studies on lung cancer and indoor radon exposure, and studies of lung cancer and leukaemia among nuclear workers exposed to transuranic nuclides (mainly uranium and plutonium), for whom organ doses will be reconstructed individually. The contribution of experts in dosimetry will allow the calculation of organ doses in presence of multiple exposures (radon decay products, uranium dust and external gamma exposure). Expression of the risk per unit organ dose will make it possible to compare results with those from other populations exposed to external radiation. The multidisciplinary approach of Alpha-Risk promotes the development of coherent and improved methodological approaches regarding risk modelling. A specific work - package is dedicated to the integration of results and their use for risk assessment, especially for radon. Alpha-Risk will contribute to a better understanding of long-term health risks following chronic low doses from internal exposures. The project also has the great potential to help resolve major public health concerns about the effects of low and/or protracted exposures, especially

  5. Health risk assessment of jobs involving ionizing radiation sources

    Directory of Open Access Journals (Sweden)

    Spasojević-Tišma Vera D.

    2011-01-01

    Full Text Available The study included 75 subjects exposed to low doses of external ionizing radiation and 25 subjects from the control group, all male. The first group (A consisted of 25 subjects employed in the production of technetium, with an average job experience of 15 years. The second group (B consisted of 25 subjects exposed to ionizing radiation from enclosed sources, working in jobs involving the control of X-ray devices and americium smoke detectors, their average work experience being 18.5 years. The third group (C consisted of 25 subjects involved in the decontamination of the terrain at Borovac from radioactive rounds with depleted uranium left over after the NATO bombing of Serbia in 1999, their average job experience being 18.5 years. The control group (K consisted of 25 subjects who have not been in contact with sources of ionizing radiation and who hold administrative positions. Frequencies of chromosome aberrations were determined in lymphocytes of peripheral blood and compared to the control group. The average annual absorbed dose determined by thermoluminescent dosimeters for all three groups did not exceed 2 mSv. In the present study, the largest number of observed changes are acentric fragments and chromosome breaks. The highest occupational risk appears to involve subjects working in manufacturing of the radio-isotope technetium.

  6. Cardiovascular risks associated with low dose ionizing particle radiation.

    Directory of Open Access Journals (Sweden)

    Xinhua Yan

    Full Text Available Previous epidemiologic data demonstrate that cardiovascular (CV morbidity and mortality may occur decades after ionizing radiation exposure. With increased use of proton and carbon ion radiotherapy and concerns about space radiation exposures to astronauts on future long-duration exploration-type missions, the long-term effects and risks of low-dose charged particle irradiation on the CV system must be better appreciated. Here we report on the long-term effects of whole-body proton ((1H; 0.5 Gy, 1 GeV and iron ion ((56Fe; 0.15 Gy, 1GeV/nucleon irradiation with and without an acute myocardial ischemia (AMI event in mice. We show that cardiac function of proton-irradiated mice initially improves at 1 month but declines by 10 months post-irradiation. In AMI-induced mice, prior proton irradiation improved cardiac function restoration and enhanced cardiac remodeling. This was associated with increased pro-survival gene expression in cardiac tissues. In contrast, cardiac function was significantly declined in (56Fe ion-irradiated mice at 1 and 3 months but recovered at 10 months. In addition, (56Fe ion-irradiation led to poorer cardiac function and more adverse remodeling in AMI-induced mice, and was associated with decreased angiogenesis and pro-survival factors in cardiac tissues at any time point examined up to 10 months. This is the first study reporting CV effects following low dose proton and iron ion irradiation during normal aging and post-AMI. Understanding the biological effects of charged particle radiation qualities on the CV system is necessary both for the mitigation of space exploration CV risks and for understanding of long-term CV effects following charged particle radiotherapy.

  7. The assessment of risks from exposure to low-levels of ionizing radiation

    International Nuclear Information System (INIS)

    This report is concerned with risk assessments for human populations receiving low level radiation doses; workers routinely exposed to radiation, Japanese victims of nuclear bombs, and the general public are all considered. Topics covered include risk estimates for cancer, mortality rates, risk estimates for nuclear site workers, and dosimetry

  8. The assessment of risks from exposure to low-levels of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, E.S.

    1992-06-01

    This report is concerned with risk assessments for human populations receiving low level radiation doses; workers routinely exposed to radiation, Japanese victims of nuclear bombs, and the general public are all considered. Topics covered include risk estimates for cancer, mortality rates, risk estimates for nuclear site workers, and dosimetry.

  9. Benefits and Risks for People and Livestock of Keeping Companion Animals: Searching for a Healthy Balance.

    Science.gov (United States)

    Sterneberg-van der Maaten, T; Turner, D; Van Tilburg, J; Vaarten, J

    2016-07-01

    The mission of the CALLISTO (Companion Animals multisectoriaL interprofessionaL Interdisciplinary Strategic Think tank On zoonoses) project was to provide an overview of the current situation on the role of companion animals as a source of infectious diseases for people and food animals. It also aimed to identify knowledge and technology gaps for the most important zoonoses and propose targeted actions to reduce the risk of zoonotic diseases transmitted via companion animals. After a 3-year study, its members have developed practical recommendations for improved data collection on companion animal numbers and the mechanisms for disease surveillance in companion animals. They highlight the importance of introducing a system for the unique identification of dogs and other companion animals with an implanted microchip transponder and storage of the details it contains on an internationally accessible online database. Their report also emphasises the need for balanced communication with the public on the risks and benefits of pet ownership and the value of the 'One Health' concept to encourage closer collaboration between veterinary and human medical professionals.

  10. Foraging patch selection in winter: a balance between predation risk and thermoregulation benefit.

    Directory of Open Access Journals (Sweden)

    Sara Villén-Pérez

    Full Text Available In winter, foraging activity is intended to optimize food search while minimizing both thermoregulation costs and predation risk. Here we quantify the relative importance of thermoregulation and predation in foraging patch selection of woodland birds wintering in a Mediterranean montane forest. Specifically, we account for thermoregulation benefits related to temperature, and predation risk associated with both illumination of the feeding patch and distance to the nearest refuge provided by vegetation. We measured the amount of time that 38 marked individual birds belonging to five small passerine species spent foraging at artificial feeders. Feeders were located in forest patches that vary in distance to protective cover and exposure to sun radiation; temperature and illumination were registered locally by data loggers. Our results support the influence of both thermoregulation benefits and predation costs on feeding patch choice. The influence of distance to refuge (negative relationship was nearly three times higher than that of temperature (positive relationship in determining total foraging time spent at a patch. Light intensity had a negligible and no significant effect. This pattern was generalizable among species and individuals within species, and highlights the preponderance of latent predation risk over thermoregulation benefits on foraging decisions of birds wintering in temperate Mediterranean forests.

  11. The Australasian radiation protection society's position statement on risks fro low levels of ionizing radiation

    International Nuclear Information System (INIS)

    Full text: Controversy continues in the radiation protection literature on whether or not ionizing radiation is harmful at low doses, with unresolved scientific uncertainty about effects below a few tens of millisieverts. To settle what regulatory controls (if any) should apply in this dose region, an assumption has to be made relating dose to the possibility of harm or benefit. The assumption made and the way it is applied can have far-reaching effects, not only on the scale of regulatory compliance required but also on public perception of risk, and therefore on the technological choices made by society. It is important therefore that decisions reached concerning the regulation of low doses of ionizing radiation derive from rational arguments and are perceived to have an ethical basis. It is also important that such decisions are neither portrayed nor perceived as resolving the scientific uncertainties: rather, they serve merely to facilitate the implementation of appropriate measures to ensure safety. At its Annual General Meeting in 2004, the Australasian Radiation Protection Society (ARPS) set up a working group to draft a statement of the Society's position on this matter. The resulting position statement was adopted by the Society at its Annual General Meeting on 14 November 2005. Its salient features are as follows: There is insufficient evidence to establish a dose-effect relationship for doses that are less than a few tens of millisieverts in a year. A linear extrapolation from higher dose levels should be assumed only for the purpose of applying regulatory controls; Estimates of collective dose arising from individual doses that are less than some tens of millisieverts in a year should not be used to predict numbers of fatal cancers; The risk to an individual of doses significantly less than 100 microsieverts in a year is so small, if it exists at all, that regulatory requirements to control exposure at this level are not warranted. The paper will

  12. A methodology for spacecraft technology insertion analysis balancing benefit, cost, and risk

    Science.gov (United States)

    Bearden, David Allen

    Emerging technologies are changing the way space missions are developed and implemented. Technology development programs are proceeding with the goal of enhancing spacecraft performance and reducing mass and cost. However, it is often the case that technology insertion assessment activities, in the interest of maximizing performance and/or mass reduction, do not consider synergistic system-level effects. Furthermore, even though technical risks are often identified as a large cost and schedule driver, many design processes ignore effects of cost and schedule uncertainty. This research is based on the hypothesis that technology selection is a problem of balancing interrelated (and potentially competing) objectives. Current spacecraft technology selection approaches are summarized, and a Methodology for Evaluating and Ranking Insertion of Technology (MERIT) that expands on these practices to attack otherwise unsolved problems is demonstrated. MERIT combines the modern techniques of technology maturity measures, parametric models, genetic algorithms, and risk assessment (cost and schedule) in a unique manner to resolve very difficult issues including: user-generated uncertainty, relationships between cost/schedule and complexity, and technology "portfolio" management. While the methodology is sufficiently generic that it may in theory be applied to a number of technology insertion problems, this research focuses on application to the specific case of small (risks) associated with advanced technology; and application of heuristics to facilitate informed system-level technology utilization decisions earlier in the conceptual design phase. MERIT extends the state of the art in technology insertion assessment selection practice and, if adopted, may aid designers in determining the configuration of complex systems that meet essential requirements in a timely, cost-effective manner.

  13. Postoperative radiation for cervical cancer with pathologic risk factors

    International Nuclear Information System (INIS)

    Purpose: To examine the efficacy of postoperative radiation therapy for early-stage cervical cancer with pathologic risk factors. Methods and Materials: We reviewed the charts of 83 patients who received postoperative radiation therapy at our facility from March 1980 to November 1993 for early stage cervix cancer with positive surgical margins, positive pelvic or periaortic lymph nodes, lymphovascular space invasion, deep invasion, or for disease discovered incidentally at simple hysterectomy. Twenty-eight patients received low dose rate (LDR) intracavitary radiation with or without external beam pelvic irradiation and 55 patients received external beam pelvic irradiation with high dose rate (HDR) intracavitary implants. Of these 83 patients, 66 were evaluable--20 LDR and 46 HDR patients. All patients received 45-50 Gy external beam irradiation and 20 Gy LDR equivalent intracavitary irradiation prescribed to 0.5 cm below the mucosa. Ninety percent of the LDR group and 92% of the HDR group completed treatment within < 56 days. Treatment-related toxicities were scored according to the GOG toxicity scale. Mean and median follow-up times were 101 months and 111 months (3-172 months) for the LDR group and 42 and 40 months (3-98 months) for the HDR group. Results: The 5-year disease-free survival was 89% for the LDR group and 72% for the HDR group. Local control was observed in 90% (18 out of 20) of the LDR patients and 89% (41 out of 46) of the HDR patients for an overall local control rate of 89.5%. Two of 20 LDR patients (10%) experienced recurrence (two pelvic with distant metastasis). Nine of 46 HDR patients (22%) had recurrence of disease (three pelvic, four distant metastasis, and two pelvic with distant metastasis). In the HDR group, 6 out of 16 (38%) with positive lymph nodes died of disease whereas, 27 out of 30 (90%) of the patients with negative lymph nodes remain free of disease. Three of 20 (15%) LDR patients and 4 out of 46 (9%) HDR patients experienced

  14. A GIS water balance approach to support surface water flood risk management

    Science.gov (United States)

    Diaz-Nieto, J.

    Concern has arisen as to whether the lack of appropriate consideration to surface water in urban spatial planning is reducing our capacity to manage surface water flood risk. Appropriate tools are required that allow spatial planners to explore opportunities and solutions for surface after flooding at large spatial scales. An urban surface water balance model has been developed that screens large urban areas to identify flooded areas and which allows solutions to be explored. The model hypothesis is that key hydrological characteristics; storage volume and location, flow paths and surface water generation capture the key processes responsible for surface water flooding> The model uses a LiDAR DEM (Light Detection and Ranging Digital Elevation Model) as the basis for determining surface water accumulation in a catchment and has been developed so that it requires minimal inputs and computational resources. The urban surface water balance approach is applied to Keighley in West Yorkshire where several instances of surface water flooding have been reported. This research used a postal questionnaire, followed up with site visits to collect data on surface water flooding locations in Keighley. A qualitative analysis based on field visits revealed that the degree of interaction with the sewer network varies spatially, and as the importance of the interaction of the sewer system increase, the accuracy of the model results are lowered. It also highlighted that local detail not present in the DEM, the presence of urban drainage assets and the performance of the sewer system which are not be represented in the model, can determine the accuracy of model results. Model results were used as a basis to develop solutions to surface water flooding. A least cost path methodology was developed to identify managed flood routes as a solution. These were translated into model inputs in the form a modified DEM.

  15. Risk concepts in various fields including radiation protection. A historical review and some recent topics

    International Nuclear Information System (INIS)

    This is a review by the expert group concerning risks in radiation protection and in chemical management, recent state of protection and of health-risk assessment of low dose radiation, and risk concepts in other fields. Risk concepts in radiation protection are described mainly on ICRP: Its history leading to its Publication 1 (1958), Pub. 9 (1965), Pub. 26 (1977) and Pub. 60 (1990). In that recent publication, the term, risk, is used only for the established one like estimated risk or excess relative risk. Risk management of chemicals involves that against pollution from environmental and ecological aspects, and assessment of dioxin and chemicals from toxicology and carcinogenicity aspects. Recently, risks of low dose radiation have been actively discussed conceivably because of possible reduction of the exposure limit in ICRP Recommendation 1990, Chernobyl accident, advances of radiation biology and radiation protection problem in the radioactive waste disposition. Globally, many academic societies such as American Health-Physics Society published Position Statements and Reports and there are activities like the Research program plan for the risk and an international conference of bridging radiation policy and science. Risk concepts involve technological and ecological ones, insurance ones and health ones. Risk assessment or analysis is done through recognition, measurement and prediction, thus through the scientific process based on objective facts. (K.H.)

  16. A theoretical concept of low level/low LET radiation carcinogenic risk (LLCR) projection

    Energy Technology Data Exchange (ETDEWEB)

    Filyushkin, I.V. [Laboratory of Theoretical Radiobiology, Moscow (Russian Federation)

    1992-06-01

    Carcinogenic risk to humans resulting from low level/low LET radiation exposure (LLLCR) has not been observed directly because epidemiological observations have not yet provided statistically significant data on risk values. However, these values are of great interest for radiation health science and radiation protection practice under both normal conditions and emergency situations. This report presents a theoretical contribution to the validation of dose and dose rate efficiency factors (DDREF) transforming cocinogenic risk coefficients from those revealed in A-bomb survivors to factors appropriate for the projection of the risk resulting from very low levels of low LET radiation.

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

    International Nuclear Information System (INIS)

    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)

  18. Risk from exposure to natural and artificial ultraviolet radiation

    International Nuclear Information System (INIS)

    The association between exposure to ultraviolet (UV) and damage to the skin and eyes is today generally accepted. Exposure to UV radiation may occur in several ways. Apart from the sun, there is a wide range of artificial sources used in different fields of industry, research and medicine, the exposure to which adds to the total exposure of an individual during his life-span. The potential effects of ozone layer depletion on the increase of the solar UV radiation at earth's surface, and therefor on human health, have recently been emphasized. Moreover, great attention has been devoted to the often uncontrolled use of UV lamps for tanning. This report shows the basis on which short and long term UV risk is assessed, and indicates some parameters necessary to its evaluation. The UV effects, both at molecular and cellular levels and on humans, are described together with their respective action spectra. The most common UV sources are then analyzed and their use in different fields is shown. Finally, some methods in dosimetry, which are useful for the correct measurement of exposure values, are described

  19. A dietary oxidative balance score of vitamin C, beta-carotene and iron intakes and mortality risk in male smoking Belgians

    NARCIS (Netherlands)

    Hoydonck, van P.G.A.; Temme, E.H.M.; Schouten, E.G.

    2002-01-01

    The purpose of this study was to investigate, in smokers, whether the oxidative balance of their dietary pattern affected mortality risk. To evaluate the oxidative balance of the dietary pattern, an oxidative balance score was constructed that summarized the combined intake of dietary antioxidants (

  20. The Australasian radiation protection society's position statement on risks from low levels of ionizing radiation

    International Nuclear Information System (INIS)

    At its Annual General Meeting in 2004, the Australasian Radiation Protection Society (A.R.P.S.) set up a working group to draft a statement of the Society's position on risks from low levels of exposure to ionizing radiation. The resulting position statement was adopted by the Society at its Annual General Meeting in 2005. Its salient features are as follows: First, there is insufficient evidence to establish a dose-effect relationship for doses that are less than a few tens of milli sieverts in a year. A linear extrapolation from higher dose levels should be assumed only for the purpose of applying regulatory controls. Secondly, estimates of collective dose arising from individual doses that are less than some tens of milli sieverts in a year should not be used to predict numbers of fatal cancers. Thirdly, the risk to an individual of doses significantly less than 100 micro sieverts in a year is so small, if it exists at all, that regulatory requirements to control exposure at this level are not warranted. (authors)

  1. Aedes aegypti Global Suitability Maps Using a Water Container Energy Balance Model for Dengue Risk Applications

    Science.gov (United States)

    Steinhoff, D.

    2015-12-01

    Dengue infections are estimated to total nearly 400 million per year worldwide, with both the geographic range and the magnitude of infections having increased in the past 50 years. The primary dengue vector mosquito Aedes aegypti is closely associated with humans. It lives exclusively in urban and semi-urban areas, preferentially bites humans, and spends its developmental stages in artificial water containers. Climate regulates the development of Ae. aegypti immature mosquitoes in artificial containers. Potential containers for Ae. aegypti immature development include, but are not limited to, small sundry items (e.g., bottles, cans, plastic containers), buckets, tires, barrels, tanks, and cisterns. Successful development of immature mosquitoes from eggs to larvae, pupae, and eventually adults is largely dependent on the availability of water and the thermal properties of the water in the containers. Recent work has shown that physics-based approaches toward modeling container water properties are promising for resolving the complexities of container water dynamics and the effects on immature mosquito development. An energy balance container model developed by the author, termed the Water Height And Temperature in Container Habitats Energy Model (WHATCH'EM), solves for water temperature and height for user-specified containers with readily available weather data. Here we use WHATCH'EM with NASA Earth Science products used as input to construct global suitability maps based on established water temperature ranges for immature Ae. aegypti mosquitoes. A proxy for dengue risk is provided from habitat suitability, but also population estimates, as Ae. aegypti is closely associated with human activity. NASA gridded Global Population of the World data is used to mask out rural areas with low dengue risk. Suitability maps are illustrated for a variety of containers (size, material, color) and shading scenarios.

  2. Radiation and energy balance dynamics over young chir pine ( Pinus roxburghii) system in Doon of western Himalayas

    Science.gov (United States)

    Singh, Nilendu; Bhattacharya, Bimal K.; Nanda, M. K.; Soni, Prafulla; Parihar, Jai Singh

    2014-10-01

    The regional impacts of future climate changes are principally driven by changes in energy fluxes. In this study, measurements on micrometeorological and biophysical variables along with surface energy exchange were made over a coniferous subtropical chir pine ( Pinus roxburghii) plantation ecosystem at Forest Research Institute, Doon valley, India. The energy balance components were analyzed for two years to understand the variability of surface energy fluxes, their drivers, and closure pattern. The period covered two growth cycles of pine in the years 2010 and 2011 without and with understory growth. Net short wave and long wave radiative fluxes substantially varied with cloud dynamics, season, rainfall induced surface wetness, and green growth. The study clearly brought out the intimate link of albedo dynamics in chir pine system with dynamics of leaf area index (LAI), soil moisture, and changes in understory background. Rainfall was found to have tight linear coupling with latent heat fluxes. Latent heat flux during monsoon period was found to be higher in higher rainfall year (2010) than in lower rainfall year (2011). Higher or lower pre-monsoon sensible heat fluxes were succeeded by noticeably higher or lower monsoon rainfall respectively. Proportion of latent heat flux to net radiation typically followed the growth curve of green vegetation fraction, but with time lag. The analysis of energy balance closure (EBC) showed that the residual energy varied largely within ±30% of net available energy and the non-closure periods were marked by higher rainspells or forced clearance of understory growths.

  3. Radiation and energy balance dynamics over young chir pine (Pinus roxburghii) system in Doon of western Himalayas

    Indian Academy of Sciences (India)

    Nilendu Singh; Bimal K Bhattacharya; M K Nanda; Prafulla Soni; Jai Singh Parihar

    2014-10-01

    The regional impacts of future climate changes are principally driven by changes in energy fluxes. In this study, measurements on micrometeorological and biophysical variables along with surface energy exchange were made over a coniferous subtropical chir pine (Pinus roxburghii) plantation ecosystem at Forest Research Institute, Doon valley, India. The energy balance components were analyzed for two years to understand the variability of surface energy fluxes, their drivers, and closure pattern. The period covered two growth cycles of pine in the years 2010 and 2011 without and with understory growth. Net short wave and long wave radiative fluxes substantially varied with cloud dynamics, season, rainfall induced surface wetness, and green growth. The study clearly brought out the intimate link of albedo dynamics in chir pine system with dynamics of leaf area index (LAI), soil moisture, and changes in understory background. Rainfall was found to have tight linear coupling with latent heat fluxes. Latent heat flux during monsoon period was found to be higher in higher rainfall year (2010) than in lower rainfall year (2011). Higher or lower pre-monsoon sensible heat fluxes were succeeded by noticeably higher or lower monsoon rainfall respectively. Proportion of latent heat flux to net radiation typically followed the growth curve of green vegetation fraction, but with time lag. The analysis of energy balance closure (EBC) showed that the residual energy varied largely within ±30% of net available energy and the non-closure periods were marked by higher rainspells or forced clearance of understory growths.

  4. An evaluation of early countermeasures to reduce the risk of internal radiation exposure after the Fukushima nuclear incident in Japan.

    Science.gov (United States)

    Nomura, Shuhei; Tsubokura, Masaharu; Gilmour, Stuart; Hayano, Ryugo S; Watanabe, Yuni N; Kami, Masahiro; Kanazawa, Yukio; Oikawa, Tomoyoshi

    2016-05-01

    After a radiation-release incident, intake of radionuclides in the initial stage immediately following the incident may be the major contributor to total internal radiation exposure for individuals in affected areas. However, evaluation of early internal contamination risk is greatly lacking. This study assessed the relationship between initial stage evacuation/indoor sheltering and internal radiation contamination levels 4 months after the 2011 Fukushima nuclear incident in Japan and estimated potential pathways of the contamination. The study population comprised 525 participants in the internal radiation screening program at Minamisoma Municipal General Hospital, 23 km north of the Fukushima nuclear plant. The analysed dataset included the results of a screening performed in July 2011, 4 months after the incident, and of a questionnaire on early-incident response behaviours, such as sheltering indoors and evacuations, completed by participants. Association between such early countermeasures and internal contamination levels of cesium-134 were assessed using Tobit multiple regression analyses. Our study shows that individuals who evacuated to areas outside Fukushima Prefecture had similar contamination levels of cesium-134 to individuals who stayed in Fukushima (relative risk: 0.86; 95% confidence interval: 0.74-0.99). Time spent outdoors had no significant relationship with contamination levels. The effects of inhalation from radiological plumes released from the nuclear plant on total internal radiation contamination might be so low as to be undetectable by the whole-body counting unit used to examine participants. Given the apparent limited effectiveness of evacuation and indoor sheltering on internal contamination, the decision to implement such early responses to a radiation-release incident should be made by carefully balancing their potential benefits and health risks.

  5. The impact of deforestation in the Amazonian atmospheric radiative balance: a remote sensing assessment

    Directory of Open Access Journals (Sweden)

    E. T. Sena

    2012-06-01

    Full Text Available This paper addresses the Amazonian radiative budget after considering three aspects of deforestation: (i the emission of aerosols from biomass burning due to forest fires; (ii changes in surface albedo after deforestation and (iii modifications in the column water vapour amount over deforested areas. Simultaneous Clouds and the Earth's Radiant Energy System (CERES shortwave fluxes and aerosol optical depth (AOD retrievals from the Moderate Resolution Imaging SpectroRadiometer (MODIS were analysed during the peak of the biomass burning seasons (August and September from 2000 to 2009. A discrete-ordinate radiative transfer (DISORT code was used to extend instantaneous remote sensing radiative forcing assessments into 24-h averages. The mean direct radiative forcing of aerosols at the top of the atmosphere (TOA during the biomass burning season for the 10-yr studied period was −5.6 ± 1.7 W m−2. Furthermore, the spatial distribution of the direct radiative forcing of aerosols over Amazon was obtained for the biomass burning season of each year. It was observed that for high AOD (larger than 1 at 550 nm the imbalance in the radiative forcing at the TOA may be as high as −20 W m−2 locally. The surface reflectance plays a major role in the aerosol direct radiative effect. The study of the effects of biomass burning aerosols over different surface types shows that the direct radiative forcing is systematically more negative over forest than over savannah-like covered areas. Values of −15.7 ± 2.4 W m−2550 nm and −9.3 ± 1.7 W m−2550 nm were calculated for the mean daily aerosol forcing efficiencies over forest and savannah-like vegetation respectively. The overall mean annual albedo-change radiative forcing due to deforestation over the state of Rondônia, Brazil, was determined as −7.3 ± 0.9 W m−2. Biomass burning aerosols impact the radiative

  6. Radiation risk statement in the participant information for a research protocol that involves exposure to ionising radiation

    International Nuclear Information System (INIS)

    A Human Research Ethics Committee (HREC) is required to scrutinise the protocols of clinical drug trials that recruit patients as participants. If the study involves exposing the participants to ionizing radiation the information provided to the participant should contain a radiation risk statement that is understandable by the Committee and the participant. The information that should be included in the risk statement is available from a variety of published sources and is discussed. The ARPANSA Code of Practice Exposure of Humans to Ionizing Radiation for Research Purposes (2005) states explicitly what the responsibilities of the researcher and the HREC are. Some research protocols do not provide the information required by good radiation protection practice and explicitly called for by the Code. Nine points (including: state that ionizing radiation is involved; that the radiation is additional to standard care; the effective dose to be received; the dose compared to natural background; the dose to the most exposed organs; a statement of risk; the benefits accruing from the exposure; ask the participant about previous exposures; name a contact person from whom information may be sought) that should be considered for inclusion in the participant information are presented and discussed. An example of a radiation risk statement is provided

  7. Combined effect of ionizing radiation and other risk factors on the incidence of breast cancer

    International Nuclear Information System (INIS)

    A study was made on combined effect of ionizing radiation (the number of roentgenoscopies and integral absorbed dose) and other risk factors (age, observation period etc) on the incidence of breast cancer (BC). It is shown that the relative BC risk, related with radiation, is affected by woman age during exposure

  8. Risk estimation of benzene-induced leukemia by radiation equivalent dose

    International Nuclear Information System (INIS)

    Based on the Hiroshima and Nagasaki epidemiological study, risk assessment system for radiation has been well developed and is practically applied to the international protection standards. Hence, defining the radiation equivalent dose for chemical agents could place in the order of their risk. As well as the radiation, benzene causes leukemia to humans. Therefore, we evaluated the radiation-equivalent dose for benzene based on chromosome aberration rates induced by its metabolites and low-dose rate radiation because chromosome aberration is thought to be closely related to the leukemogenesis. Using radiation risk coefficient, the leukemia risk caused by 1 mg/m3 benzene inhalation was estimated 5.5 - 7.3 x 10-8, which is underestimated compared to other studies based on human epidemiological researches. (author)

  9. Mechanistic and genetic studies of radiation tumorigenesis in the mouse - implications for low dose risk estimation

    International Nuclear Information System (INIS)

    Radiation cancer risk estimates remain firmly based upon epidemiological data. Experimental validation of the fundamental aspects of these risk estimates relies on animal studies. In particular, animal model systems for radiation carcinogenesis can provide data for mechanistic modelling approaches to risk estimation. The accuracy and validity of risk estimation models developed will depend upon the extent of our understanding of the process of radiation carcinogenesis. The study of 'spontaneous' tumours in humans continues to provide a sound context in which to consider the mechanisms of radiation carcinogenesis. Several mouse radiation carcinogenesis systems are considered here with particular reference to the nature of the initiating event and the influence of genetic susceptibility on radiation-induced cancer. (author)

  10. [Balancing risks and benefits of mammography screening for breast cancer: would you support its recommendation in Peruvian women?].

    Science.gov (United States)

    Posso, Margarita; Puig, Teresa; Bonfill, Xavier

    2015-01-01

    The aim of this study is to assess the balance between benefits and risks of population-based mammography screening programs in Peruvian women. We followed the criteria proposed by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) working group. A generic search strategy for published studies was performed using Medline and other sources of national data (gray literature). The evidence of benefits, risks, costs and preferences of the population was used in order to state a recommendation in favour, or against, screening. We found five systematic reviews (SR) that evaluated the balance between benefit and risks, two economic evaluations based on Peruvian data, and one study that reported the preferences of Peruvian women. The quality of evidence of the SR was moderate in favour of screening in women aged 50-69 years. The balance of risks and benefits showed a higher probability of overdiagnosis compared with the reduction in mortality. The most cost-effective strategy was the triennial mammography. Perceived barriers could seriously compromise the participation of women. In conclusion, the recommendation of mammography screening for Peruvian women is weak, even more if we take into account other health necessities of the population. However, if implemented, triennial mammography in women aged 50-69 years could be the more suitable screening strategy.

  11. A meta-analysis of leukaemia risk from protracted exposure to low-dose gamma radiation

    OpenAIRE

    Daniels, R D; Schubauer-Berigan, M K

    2010-01-01

    Context More than 400 000 workers annually receive a measurable radiation dose and may be at increased risk of radiation-induced leukaemia. It is unclear whether leukaemia risk is elevated with protracted, low-dose exposure. Objective We conducted a meta-analysis examining the relationship between protracted low-dose ionising radiation exposure and leukaemia. Data sources Reviews by the National Academies and United Nations provided a summary of informative studies published before 2005. PubM...

  12. Reevaluation of a Radiation Risk Coefficient Based on a Review of the DDREF of Radiation Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Urabe, I.

    2004-07-01

    On the basis of the consideration of the dose rate effectiveness of radiation exposure a sigmoid curve was fitted to the solid cancer dose response by A-bomb survivors. Since the variation of the ERR of solid cancer mortality could be represented by the sigmoid function, the DDREF of 10 was obtained by using the ERR per Sv around the weighted dose of 0.9 Sv (inflection point of the sigmoid curve) and 0.1 Sv (dose limit per 5 year or emergency) of the curve fitted. Though this might be large than the present value, the DDREF obtained here could be supported by the results of the studies in experimental human cells and animals conducting over wide dose and dose rate range such as acute, protracted and chronic exposure, which gave dose rate effectiveness factors from about 1 to 10 or more. Furthermore, it was quite possible that the higher DDREF would be explained by the acquirement of abilities of reducing the effects by radiation exposures. Based on these discussion, it has become clear that applying the DDREF of 10 yields a nominal value of 1x 10''-2 Sv for the probability of induced fatal caner in a population. And the annual mortality risk of 1x10''-5/y corresponding to the exposure of 1 mSv/y, which was on the order of the external annual background doses, was considered to be reasonable because it was well known that incidences below the risk of 1x10''-5/y were the events that the people did not show much concern about protective actions for mitigating the detriment in the society. (Author) 15 refs.

  13. Assessment of balance and risk for falls in a sample of community-dwelling adults aged 65 and older

    Directory of Open Access Journals (Sweden)

    Colonvega Makasha

    2006-01-01

    Full Text Available Abstract Background Falls are a major health concern for older adults and their impact is a significant public health problem. The chief modifiable risk factors for falls in community-dwellers are psychotropic drugs, polypharmacy, environmental hazards, poor vision, lower extremity impairments, and balance impairments. This study focused on balance impairments. Its purpose was to assess the feasibility of recruiting older adults with possible balance problems for research conducted at a chiropractic research center, and to explore the utility of several widely used balance instruments for future studies of the effect of chiropractic care on balance in older adults. Methods This descriptive study was conducted from September through December 2004. Participants were recruited through a variety of outreach methods, and all were provided with an educational intervention. Data were collected at each of two visits through questionnaires, interviews, and physical examinations. Balance was assessed on both visits using the Activities-specific Balance Confidence Scale (ABCS, the Berg Balance Scale (BBS, and the One Leg Standing Test (OLST. Results A total of 101 participants enrolled in the study. Advertising in the local senior newspaper was the most effective method of recruitment (46%. The majority of our participants were white (86% females (67%. About one third (32% of participants had a baseline BBS score below 46, the cut-off point for predicting risk of falling. A mean improvement in BBS scores of 1.7 points was observed on the second visit. For the subgroup with baseline scores below 46, the mean change was 4.5 points, but the group mean remained below 46 (42.5. Conclusion Recruitment of community-dwelling seniors for fall-related research conducted at a chiropractic research center appears feasible, and the most successful recruitment strategies for this center appeared to be a combination of targeted newspaper ads and personal contact through

  14. Balancing Potency of Platelet Inhibition with Bleeding Risk in the Early Treatment of Acute Coronary Syndrome

    Directory of Open Access Journals (Sweden)

    Slattery, David E

    2009-08-01

    challenge in choosing appropriate therapy in the emergency department lies in balancing the need for potent platelet inhibition with the potential for increased risk of bleeding and future interventions the patient is likely to receive during the index hospitalization.[WestJEM. 2009;10:163-175.

  15. What is risk perception in general and in radiation protection?

    International Nuclear Information System (INIS)

    In view of the universal roll Risk Perception plays in our daily life, the author makes an effort to understand this notion better. For such a subtle task, it will be good to know something about the person, who undertakes such a challenge. Thus, he first makes a short description of himself in a number of relevant personal feature, emphasising rather what he is not: cadre of insurance company.... etc. He starts with a literal understanding of the idiom Risk Perception in English and in other languages (in Chinese). This formulation, still abstract, is framed with concrete objects, and materialised into touchable structures. He then puts life into these structures, and makes them accessible to emotion and experience. Now that this notion is animated, he follows it's way into life in the field of Radiation Protection, and find among others that the term Cost and Benefit correspond to the Chinese idiom, and that the system of Justification and Optimisation is as difficult to achieve objectively as an Upright Walk on the Confucian Path to-ward the Middle. One of the difficulties lies in the difference in the scale in estimating values. For instance, though the idea of Asian and Western Values are rather diffuse, their difference is never-the-less high enough to render it to be insurmountable, at least at present. These observation belong actually to common experience of Health physicists, and nothing new or spectacular is presented. The author emphasises only, again not a new idea of his own, only putting weight to, that perception depends on point of view, or rather on stand of viewing points, and rarely represent the whole story, the true situation. This leads, according to the author, to the well known and accepted term of Risk Residuum, in German, Rest Risiko. Despite of partialness of all perceptions, solid decisions are based on perception. We all know mournful consequences of unsound decision in our daily life. It is tragic, when this happens in history. The

  16. Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

    International Nuclear Information System (INIS)

    The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and MicrotoxR toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The MicrotoxR toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The MicrotoxR toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent

  17. Assessment of radiation risk as a part of ecological risk in the Republic of Belarus after the Chernobyl accident

    International Nuclear Information System (INIS)

    Full text: The purpose of the work: foundation for principles of planning protection measures, that provide safety for population activity on the territories, contaminated with radio-nuclides, by analysing radio-chemical situation, using risk assessment methods. Problems set in the work: -) Analyses of radiation risk in the structure of ecological risk in the territory of the Republic of Belarus after the Chernobyl accident; -) Investigation of chemical risk level, connected with air pollution from stationary objects exhausts, for the territories, contaminated with Chernobyl radio-nuclides; -) Modelling of the combined impact of ionising radiation and chemical carcinogen for the possible ecological risk assessment; -) Involving modern geo informational systems in the radio-ecological risk assessment process; -) Foundation for the assessment methodology of the complex influence of negative factors in the territories, contaminated with Chernobyl radio-nuclides. The problems are solved by carrying out specific experiments and by analysing published and own data on radioactive and chemical contamination of some regions of Belarus. Major findings: Radiation input to the really registered carcinogens is estimated to app. 10 %. In case of multiple factors influence of different contaminators of industrial and natural origin (i.e. radiation is not the only negative factor), ignorance of non-radiation origin factors may seriously distort estimation of radiation risk, when it is related to the registered effects. Radiation should be in no way treated as the major factor of real ecological risk in Belarus. Method for comparative analysis of territories' ecological risk level is developed and implemented. A GIS segment, that includes subsystem of the real and forecasted radio-ecological mapping, is created. The authors grounded the experimental model for study the complex influence of radioactive and non-radioactive (chemical carcinogen) factors. Revealed dependencies 'dose

  18. 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

    Science.gov (United States)

    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.

  19. Space Radiation Heart Disease Risk Estimates for Lunar and Mars Missions

    Science.gov (United States)

    Cucinotta, Francis A.; Chappell, Lori; Kim, Myung-Hee

    2010-01-01

    The NASA Space Radiation Program performs research on the risks of late effects from space radiation for cancer, neurological disorders, cataracts, and heart disease. For mortality risks, an aggregate over all risks should be considered as well as projection of the life loss per radiation induced death. We report on a triple detriment life-table approach to combine cancer and heart disease risks. Epidemiology results show extensive heterogeneity between populations for distinct components of the overall heart disease risks including hypertension, ischaemic heart disease, stroke, and cerebrovascular diseases. We report on an update to our previous heart disease estimates for Heart disease (ICD9 390-429) and Stroke (ICD9 430-438), and other sub-groups using recent meta-analysis results for various exposed radiation cohorts to low LET radiation. Results for multiplicative and additive risk transfer models are considered using baseline rates for US males and female. Uncertainty analysis indicated heart mortality risks as low as zero, assuming a threshold dose for deterministic effects, and projections approaching one-third of the overall cancer risk. Medan life-loss per death estimates were significantly less than that of solid cancer and leukemias. Critical research questions to improve risks estimates for heart disease are distinctions in mechanisms at high doses (>2 Gy) and low to moderate doses (basic understanding of radiation doserate and quality effects, and individual sensitivity.

  20. Space Radiation Heart Disease Risk Estimates for Lunar and Mars Missions

    Science.gov (United States)

    Cucinotta, Francis A.; Chappell, Lori; Kim, Myung-Hee

    2010-01-01

    The NASA Space Radiation Program performs research on the risks of late effects from space radiation for cancer, neurological disorders, cataracts, and heart disease. For mortality risks, an aggregate over all risks should be considered as well as projection of the life loss per radiation induced death. We report on a triple detriment life-table approach to combine cancer and heart disease risks. Epidemiology results show extensive heterogeneity between populations for distinct components of the overall heart disease risks including hypertension, ischaemic heart disease, stroke, and cerebrovascular diseases. We report on an update to our previous heart disease estimates for Heart disease (ICD9 390-429) and Stroke (ICD9 430-438), and other sub-groups using recent meta-analysis results for various exposed radiation cohorts to low LET radiation. Results for multiplicative and additive risk transfer models are considered using baseline rates for US males and female. Uncertainty analysis indicated heart mortality risks as low as zero, assuming a threshold dose for deterministic effects, and projections approaching one-third of the overall cancer risk. Medan life-loss per death estimates were significantly less than that of solid cancer and leukemias. Critical research questions to improve risks estimates for heart disease are distinctions in mechanisms at high doses (>2 Gy) and low to moderate doses (<2 Gy), and data and basic understanding of radiation doserate and quality effects, and individual sensitivity.

  1. The communication of the radiation risk from CT in relation to its clinical benefit in the era of personalized medicine. Pt. 1. The radiation risk from CT

    International Nuclear Information System (INIS)

    The theory of radiation carcinogenesis has been debated for decades. Most estimates of the radiation risks from CT have been based on extrapolations from the lifespan follow-up study of atomic bomb survivors and on follow-up studies after therapeutic radiation, using the linear no-threshold theory. Based on this, many population-based projections of induction of future cancers by CT have been published that should not be used to estimate the risk to an individual because of their large margin of error. This has changed recently with the publication of three large international cohort follow-up studies, which link observed cancers to CT scans received in childhood. A fourth ongoing multi-country study in Europe is expected to have enough statistical power to address the limitations of the prior studies. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report released in 2013 specifically addresses variability in response of the pediatric population exposed to ionizing radiation. Most authorities now conclude that there is enough evidence to link future cancers to the radiation exposure from a single CT scan in childhood but that cancer risk estimates for individuals must be based on the specifics of exposure, age at exposure and absorbed dose to certain tissues. Generalizations are not appropriate, and the communication of the CT risk to individuals should be conducted within the framework of personalized medicine. (orig.)

  2. The communication of the radiation risk from CT in relation to its clinical benefit in the era of personalized medicine. Pt. 1. The radiation risk from CT

    Energy Technology Data Exchange (ETDEWEB)

    Westra, Sjirk J. [Massachusetts General Hospital, Division of Pediatric Radiology, Boston, MA (United States)

    2014-10-15

    The theory of radiation carcinogenesis has been debated for decades. Most estimates of the radiation risks from CT have been based on extrapolations from the lifespan follow-up study of atomic bomb survivors and on follow-up studies after therapeutic radiation, using the linear no-threshold theory. Based on this, many population-based projections of induction of future cancers by CT have been published that should not be used to estimate the risk to an individual because of their large margin of error. This has changed recently with the publication of three large international cohort follow-up studies, which link observed cancers to CT scans received in childhood. A fourth ongoing multi-country study in Europe is expected to have enough statistical power to address the limitations of the prior studies. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report released in 2013 specifically addresses variability in response of the pediatric population exposed to ionizing radiation. Most authorities now conclude that there is enough evidence to link future cancers to the radiation exposure from a single CT scan in childhood but that cancer risk estimates for individuals must be based on the specifics of exposure, age at exposure and absorbed dose to certain tissues. Generalizations are not appropriate, and the communication of the CT risk to individuals should be conducted within the framework of personalized medicine. (orig.)

  3. Relevance of Fukushima Nuclear Accident to India: Nuclear Radiation Risk and Interventions to Mitigate Adverse Fallout

    Directory of Open Access Journals (Sweden)

    Yadav Kapil, Varshney Neha, Aslesh OP, Karmakar MG, Pandav Chandrakant S

    2012-09-01

    Full Text Available The environmental radiation release from Fukushima nuclear power following tsunami in Japan has once again highlighted the omnipotent risk of radiation injury in the today’s world. India is at a real risk from radiation fallout both due to nuclear power plant accidents and nuclear warfare threat. The risk from nuclear radiation accident in India is further increased by the region being endemic for iodine deficiency as adverse effects following nuclear radiation fallout like thyroid cancer is significantly higher in iodine deficient populations .There is need to institute disaster preparedness measures to mitigate the damage in case of a nuclear accident. Interventions to control adverse fallout of nuclear radiation include evacuation, sheltering and food controls as well as iodine prophylaxis

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

    International Nuclear Information System (INIS)

    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)

  5. End-To-End Risk Assesment: From Genes and Protein to Acceptable Radiation Risks for Mars Exploration

    Science.gov (United States)

    Cucinotta, Francis A.; Schimmerling, Walter

    2000-07-01

    The human exploration of Mars will impose unavoidable health risks from galactic cosmic rays (GCR) and possibly solar particle events (SPE). It is the goal of NASA's Space Radiation Health Program to develop the capability to predict health risks with significant accuracy to ensure that risks are well below acceptable levels and to allow for mitigation approaches to be effective at reasonable costs. End-to-End risk assessment is the approach being followed to understand proton and heavy ion damage at the molecular, cellular, and tissue levels in order to predict the probability of the major health risk including cancer, neurological disorders, hereditary effects, cataracts, and acute radiation sickness and to develop countermeasures for mitigating risks.

  6. Sensitivity of a distributed temperature-radiation index melt model based on AWS observations and surface energy balance fluxes, Hurd Peninsula glaciers, Livingston Island, Antarctica

    Directory of Open Access Journals (Sweden)

    U. Y. Jonsell

    2012-05-01

    Full Text Available We use an automatic weather station and surface mass balance dataset spanning four melt seasons collected on Hurd Peninsula Glaciers, South Shetland Islands, to investigate the point surface energy balance, to determine the absolute and relative contribution of the various energy fluxes acting on the glacier surface and to estimate the sensitivity of melt to ambient temperature changes. Long-wave incoming radiation is the main energy source for melt, while short-wave radiation is the most important flux controlling the variation of both seasonal and daily mean surface energy balance. Short-wave and long-wave radiation fluxes do, in general, balance each other, resulting in a high correspondence between daily mean net radiation flux and available melt energy flux. We calibrate a distributed melt model driven by air temperature and an expression for the incoming short-wave radiation. The model is calibrated with the data from one of the melt seasons and validated with the data of the three remaining seasons. The model results deviate at most 140 mm w.e. from the corresponding observations using the glaciological method. The model is very sensitive to changes in ambient temperature: a 0.5 °C increase results in 56 % higher melt rates.

  7. Radiation and other risk issues in Norwegian newspapers ten years after Chernobyl

    International Nuclear Information System (INIS)

    Content analysis of risk articles has been performed in 1996 for five Norwegian newspapers four weeks before and four weeks after the 10th anniversary of the Chernobyl accident in 1986. The main focus has been on radiation and/or nuclear risks. The report is part of an international project on risk perception and communication. 94 refs

  8. Radiation and other risk issues in Norwegian newspapers ten years after Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Aa.; Reitan, J.B.; Toennesen, A.; Waldahl, R.

    1997-09-01

    Content analysis of risk articles has been performed in 1996 for five Norwegian newspapers four weeks before and four weeks after the 10th anniversary of the Chernobyl accident in 1986. The main focus has been on radiation and/or nuclear risks. The report is part of an international project on risk perception and communication. 94 refs.

  9. Communication of radiation risk in nuclear medicine: Are we saying the right thing?

    International Nuclear Information System (INIS)

    The radiation risk arising from nuclear medicine investigations represents a small but manageable risk to patients and it needs to be effectively communicated to them. Frequently in the culture of “doctor knows best,” patients trust their doctors to do whatever is right and appropriate and leave it to them to worry about any attendant risks associated with any tests involving the use of radiation. The benefit to the patient of having a speedier diagnosis and a further guide to management may not be effectively communicated in a comprehensive, timely and professional manner. In this article, we address the issue of communication of radiation risk and benefits to patients and the basis for such information. While there are different ways of communicating radiation risk, we recognize that certain basic parameters are absolutely essential for patients to enable them to make an informed choice about undergoing a nuclear medicine investigation under the direction of a well-trained and qualified individual

  10. Communication of radiation risk in nuclear medicine: Are we saying the right thing?

    Science.gov (United States)

    Pandit, Manish; Vinjamuri, Sobhan

    2014-07-01

    The radiation risk arising from nuclear medicine investigations represents a small but manageable risk to patients and it needs to be effectively communicated to them. Frequently in the culture of "doctor knows best," patients trust their doctors to do whatever is right and appropriate and leave it to them to worry about any attendant risks associated with any tests involving the use of radiation. The benefit to the patient of having a speedier diagnosis and a further guide to management may not be effectively communicated in a comprehensive, timely and professional manner. In this article, we address the issue of communication of radiation risk and benefits to patients and the basis for such information. While there are different ways of communicating radiation risk, we recognize that certain basic parameters are absolutely essential for patients to enable them to make an informed choice about undergoing a nuclear medicine investigation under the direction of a well-trained and qualified individual. PMID:25210276

  11. Radiative Energy Balance in the Tropical Tropopause Layer: An Investigation with ARM Data

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Qiang

    2013-10-22

    The overall objective of this project is to use the ARM observational data to improve our understanding of cloud-radiation effects in the tropical tropopause layer (TTL), which is crucial for improving the simulation and prediction of climate and climate change. In last four and half years, we have been concentrating on (i) performing the comparison of the ice cloud properties from the ground-based lidar observations with those from the satellite CALIPSO lidar observations at the ARM TWP sites; (ii) analyzing TTL cirrus and its relation to the tropical planetary waves; (iii) calculating the radiative heating rates using retrieved cloud microphysical properties by combining the ground-based lidar and radar observations at the ARM TWP sites and comparing the results with those using cloud properties retrieved from CloudSat and CALIPSO observations; (iv) comparing macrophysical properties of tropical cirrus clouds from the CALIPSO satellite and from ground-based micropulse and Raman lidar observations; (v) improving the parameterization of optical properties of cirrus clouds with small effective ice particle sizes; and (vi) evaluating the enhanced maximum warming in the tropical upper troposphere simulated by the GCMs. The main results of our research efforts are reported in the 12 referred journal publications that acknowledge the DOE Grant No. DE-FG02-09ER64769.

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

    Science.gov (United States)

    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.

  13. Risk of cataract among medical staff in neurosurgical department occupationally exposed to radiation

    International Nuclear Information System (INIS)

    In this study we present the risk of cataract among medical staff in neurosurgical department occupationally exposed to radiation compared to those of non-radiation workers. Cataract is the most common degenerative opacity of the crystalline lens developing with aging. Other risk factors for cataract are: infrared and ultraviolet radiation, systemic diseases (diabetes, hypertonic disease), eye diseases (glaucoma, high myopia), drugs (steroids), etc. High risk of developing cataract we find among staff occupationally exposed to radiation during operations - interventional cardiologists and neurosurgeons. This study includes 30 people between 33 and 60 years of age working in neurosurgical department and control group (the same amount and age of people not exposed to radiation in their work). After visual acuity measurement, the lens was examined by retroillumination method (red reflex) and using a bio microscope. The patients were asked for presence of ocular and systemic diseases, eye trauma, drug, alcohol and tobacco abuse and for how many years they work in this department. There was one case with cataract among neurosurgeons. The doctor doesn't have eye or systemic diseases, doesn't take any drugs and is not alcohol or tobacco abuser. In the control group there were two persons with subcapsular cataract but they have diabetes. Radiation is one of the risk factors for cataract. Continuing of this epidemiological survey will provide further knowledge on the potential risk of occupational radiation-induced cataract among neurosurgical staff and will contribute for optimization of radiation protection. (authors)

  14. Balancing the risks of stillbirth and neonatal death in the early preterm small-for-gestational-age fetus

    Science.gov (United States)

    TRUDELL, Amanda S.; TUULI, Methodius G.; CAHILL, Alison G.; MACONES, George A.; ODIBO, Anthony O.

    2014-01-01

    Objective Timing of delivery for the early preterm small for gestational age (SGA) fetus remains unknown. Our aim was to estimate the risk of stillbirth in the early preterm SGA fetus compared to the risk of neonatal death. Study Design We performed a retrospective cohort study of singleton pregnancies undergoing second trimester anatomy ultrasound excluding fetal anomalies, aneuploidy and pregnancies with incomplete neonatal follow-up. SGA was defined as birthweight < 10th percentile by the Alexander standard. Life-table analysis was used to calculate the cumulative risks of stillbirth/10,000 ongoing SGA pregnancies and risk of neonatal death/10,000 SGA live births for 2 week GA strata in the early preterm period (24-33 and 6/7 weeks). We further examined the composite risk of expectant management and then compared the risk of expectant management with the risk of immediate delivery. Results Of 76,453 singleton pregnancies, 7,036 SGA pregnancies meeting inclusion criteria were ongoing at 24 weeks with 64 stillbirths, 226 live births and 18 neonatal deaths between 24-33 and 6/7 weeks. As the risk of stillbirth increases with advancing GA, the risk of neonatal death falls, until the 32-33 and 6/7 week GA stratum. The relative risk of expectant management compared with immediate delivery remains <1 for each gestational age strata. Conclusion Our findings suggest the balance between the competing risks of stillbirth and neonatal death for the early preterm SGA fetus occurs at 32-33 and 6/7 weeks. These data can be useful when delivery timing remains uncertain. PMID:24746999

  15. Library 2.0: Balancing the Risks and Benefits to Maximise the Dividends

    Science.gov (United States)

    Kelly, Brian; Bevan, Paul; Akerman, Richard; Alcock, Jo; Fraser, Josie

    2009-01-01

    Purpose: The purpose of this paper is to provide a number of examples of how Web 2.0 technologies and approaches (Library 2.0) are being used within the library sector. The paper acknowledges that there are a variety of risks associated with such approaches. The paper describes the different types of risks and outlines a risk assessment and risk…

  16. Radiation risk perception: a discrepancy between the experts and the general population

    International Nuclear Information System (INIS)

    Determining the differences in the perception of risks between experts who are regularly exposed to radiation, and lay people provides important insights into how potential hazards may be effectively communicated to the public. In the present study we examined lay people's (N = 1020) and experts' (N = 332) perception of five different radiological risks: nuclear waste, medical x-rays, natural radiation, an accident at a nuclear installation in general, and the Fukushima accident in particular. In order to link risk perception with risk communication, media reporting about radiation risks is analysed using quantitative and qualitative content analyses. The results showed that experts perceive radiological risks differently from the general public. Experts' perception of medical X-rays and natural radiation is significantly higher than in general population, while for nuclear waste and an accident at a nuclear installation, experts have lower risk perception than the general population. In-depth research is conducted for a group of workers that received an effective dose higher than 0.5 mSv in the year before the study; for this group we identify predictors of risk perception. The results clearly show that mass media don't use the same language as technical experts in addressing radiological risks. The study demonstrates that the discrepancy in risk perception and the communication gap between the experts and the general population presents a big challenge in understanding each other

  17. Solar radiation and energy balance in polyethylene covered greenhouse; Balancos de radiacao solar e de energia em estufa com cobertura de polietileno

    Energy Technology Data Exchange (ETDEWEB)

    Frisina, Valeria de Almeida; Escobedo, Joao Francisco [UNESP, Botucatu, SP (Brazil). Faculdade de Ciencias Agronomicas. Dept. de Ciencias Ambientais

    1998-07-01

    The objective of this paper is describe the radiation and energy balance, during the lettuce (Lactuca sativa, L, var Veronica) crop cycle inside a polyethylene greenhouse. The radiation and energy balance was made inside of a tunnel greenhouse with polyethylene cover (100 {mu} m) and in an external area, both area with 35 m{sup 2}. Global (R{sub G}), reflected (R{sub r}) and net radiation (SR), soil heat flux and air temperature (dry and humid) were measured during crop cycle, in this two environment. In the data acquisition it was utilized a DATALOGGER, which operated at 1 Hz frequency, storing 5 minutes averages. The global and reflected radiations (MJ/m{sup 2}) allowed the verification that the average transmission of global radiation (R-G{sub in}/R{sub Gex}) was almost constant, near 79,59% while the average ratio of reflected radiation (R{sub rin}/R{sub rex}) was 69,21% with 8,47% standard-deviation. The short-wave radiation average (SRoc) was bigger in the external area. The normalized relation (SR/R{sub G}) was bigger in the external area, about 12%, when the green culture covered (SRol) was bigger outside, about 50%. The energy balance, estimated in terms of vertical fluxes, showed that, for the external area, in average, 83,07% of total net radiation was converted in latent heat evaporation; 18% in soil heat flux and 9,96% in sensible heat, while, inside of the greenhouse, 58,71% of total net radiation was converted in latent heat evaporation:; 42,68% in sensible heat and 28,79% in soil heat flux. (author)

  18. Biologically motivated tumor-models used for risk estimates at low doses of radiation

    International Nuclear Information System (INIS)

    Biologically motivated tumour models are necessary for estimating the radiation risk at low doses, as epidemiological studies cannot give significant results for sufficiently small risks as a matter of principle. The tumour models combine knowledge about the mechanisms of tumour development with epidemiological data and results of animal experiments. The are usefuls for testing hypothesis on radiation carcinogenesis. In the framework of EU-projects European partners work on the difficult task of quantifying the relevant biological parameters, and the radiation risk at low doses. Various data sets are described well by assuming an initiating and a promoting action of radiation. As an example a new analysis of radon-induced lung tumours in the Colorado plateau miners is discussed. The estimated lifetime relative risk extrapolated to exposures as they hold in indoor situations is substantially lower than estimated in the BEIR VI report. (orig.)

  19. Perception of Radiation Risk by Japanese Radiation Specialists Evaluated as a Safe Dose Before the Fukushima Nuclear Accident.

    Science.gov (United States)

    Miura, Miwa; Ono, Koji; Yamauchi, Motohiro; Matsuda, Naoki

    2016-06-01

    From October to December 2010, just before the radiological accident at the Fukushima Daiichi nuclear power plant, 71 radiation professionals from radiation facilities in Japan were asked what they considered as a "safe dose" of radiation for themselves, their partners, parents, children, siblings, and friends. Although the 'safe dose' they noted varied widely, from less than 1 mSv y to more than 100 mSv y, the average dose was 35.6 mSv y, which is around the middle point between the legal exposure dose limits for the annual average and for any single year. Similar results were obtained from other surveys of members of the Japan Radioisotope Association (36.9 mSv y) and of the Oita Prefectural Hospital (36.8 mSv y). Among family members and friends, the minimum average "safe" dose was 8.5 mSv y for children, for whom 50% of the responders claimed a "safe dose" of less than 1 mSv. Gender, age and specialty of the radiation professional also affected their notion of a "safe dose." These findings suggest that the perception of radiation risk varies widely even for radiation professionals and that the legal exposure dose limits derived from regulatory science may act as an anchor of safety. The different levels of risk perception for different target groups among radiation professionals appear similar to those in the general population. The gap between these characteristics of radiation professionals and the generally accepted picture of radiation professionals might have played a role in the state of confusion after the radiological accident. PMID:27115222

  20. Possible application of fuzzy set theory to radiation protection and risk assessment

    International Nuclear Information System (INIS)

    In radiation protection and risk assessment human factors play an important role. Human reliability and performance would be affected by many factors: medical, physiological and psychological, etc.. The uncertainty involved in human factors may not necessarily be probabilistic, but fuzzy. Possible application of fuzzy set theory to radiation protection and risk assessment is discussed in this paper with the introduction of the concept of possibility. 5 refs. (Author)

  1. The relevance of animal experimental results for the assessment of radiation genetic risks in man

    International Nuclear Information System (INIS)

    No suitable data are available from man for the quantitative assessment of genetic radiation risk. Therefore, the results from experiments on animals must be utilized. Two hypotheses are presented here in drawing analogical conclusions from one species to another. Although the extrapolation of results from animal experiments remains an open question, the use of experimental results from mice seems to be justified for an assessment of the genetic radiation risk in man. (orig.)

  2. Radiation exposure and mortality risk from CT and PET imaging of patients with malignant lymphoma

    OpenAIRE

    Nievelstein, R. A. J.; Quarles van Ufford, H.M.E.; Kwee, T. C.; Bierings, M.B.; Ludwig, I.; Beek, F. J. A.; de Klerk, J. M. H.; Mali, W P Th M; de Bruin, P.W.; Geleijns, J.

    2012-01-01

    Objective To quantify radiation exposure and mortality risk from computed tomography (CT) and positron emission tomography (PET) imaging with 18F-fluorodeoxyglucose (18F-FDG) in patients with malignant lymphoma (Hodgkin’s disease [HD] or non-Hodgkin’s lymphoma [NHL]). Methods First, organ doses were assessed for a typical diagnostic work-up in children with HD and adults with NHL. Subsequently, life tables were constructed for assessment of radiation risks, also taking into account the diseas...

  3. Space radiation risks for astronauts on multiple International Space Station missions.

    Science.gov (United States)

    Cucinotta, Francis A

    2014-01-01

    Mortality and morbidity risks from space radiation exposure are an important concern for astronauts participating in International Space Station (ISS) missions. NASA's radiation limits set a 3% cancer fatality probability as the upper bound of acceptable risk and considers uncertainties in risk predictions using the upper 95% confidence level (CL) of the assessment. In addition to risk limitation, an important question arises as to the likelihood of a causal association between a crew-members' radiation exposure in the past and a diagnosis of cancer. For the first time, we report on predictions of age and sex specific cancer risks, expected years of life-loss for specific diseases, and probability of causation (PC) at different post-mission times for participants in 1-year or multiple ISS missions. Risk projections with uncertainty estimates are within NASA acceptable radiation standards for mission lengths of 1-year or less for likely crew demographics. However, for solar minimum conditions upper 95% CL exceed 3% risk of exposure induced death (REID) by 18 months or 24 months for females and males, respectively. Median PC and upper 95%-confidence intervals are found to exceed 50% for several cancers for participation in two or more ISS missions of 18 months or longer total duration near solar minimum, or for longer ISS missions at other phases of the solar cycle. However, current risk models only consider estimates of quantitative differences between high and low linear energy transfer (LET) radiation. We also make predictions of risk and uncertainties that would result from an increase in tumor lethality for highly ionizing radiation reported in animal studies, and the additional risks from circulatory diseases. These additional concerns could further reduce the maximum duration of ISS missions within acceptable risk levels, and will require new knowledge to properly evaluate.

  4. Radiation exposure and circulatory disease risk: Hiroshima and Nagasaki atomic bomb survivor data, 1950-2003

    OpenAIRE

    Shimizu, Yukiko; Kodama, Kazunori; Nishi, Nobuo; Kasagi, Fumiyoshi; Suyama, Akihiko; Soda, Midori; Grant, Eric J; Sugiyama, Hiromi; Sakata, Ritsu; Moriwaki, Hiroko; Hayashi, Mikiko; Konda, Manami; Shore, Roy E.

    2010-01-01

    Objective To investigate the degree to which ionising radiation confers risk of mortality from heart disease and stroke. Design Prospective cohort study with more than 50 years of follow-up. Setting Atomic bomb survivors in Hiroshima and Nagasaki, Japan. Participants 86 611 Life Span Study cohort members with individually estimated radiation doses from 0 to >3 Gy (86% received

  5. Component greenhouse gas fluxes and radiative balance from two deltaic marshes in Louisiana: Pairing chamber techniques and eddy covariance

    Science.gov (United States)

    Krauss, Ken W.; Holm, Guerry O.; Perez, Brian C.; McWhorter, David E.; Cormier, Nicole; Moss, Rebecca F.; Johnson, Darren J.; Neubauer, Scott C.; Raynie, Richard C.

    2016-06-01

    Coastal marshes take up atmospheric CO2 while emitting CO2, CH4, and N2O. This ability to sequester carbon (C) is much greater for wetlands on a per area basis than from most ecosystems, facilitating scientific, political, and economic interest in their value as greenhouse gas sinks. However, the greenhouse gas balance of Gulf of Mexico wetlands is particularly understudied. We describe the net ecosystem exchange (NEEc) of CO2 and CH4 using eddy covariance (EC) in comparison with fluxes of CO2, CH4, and N2O using chambers from brackish and freshwater marshes in Louisiana, USA. From EC, we found that 182 g C m-2 yr-1 was lost through NEEc from the brackish marsh. Of this, 11 g C m-2 yr-1 resulted from net CH4 emissions and the remaining 171 g C m-2 yr-1 resulted from net CO2 emissions. In contrast, -290 g C m2 yr-1 was taken up through NEEc by the freshwater marsh, with 47 g C m-2 yr-1 emitted as CH4 and -337 g C m-2 yr-1 taken up as CO2. From chambers, we discovered that neither site had large fluxes of N2O. Sustained-flux greenhouse gas accounting metrics indicated that both marshes had a positive (warming) radiative balance, with the brackish marsh having a substantially greater warming effect than the freshwater marsh. That net respiratory emissions of CO2 and CH4 as estimated through chamber techniques were 2-4 times different from emissions estimated through EC requires additional understanding of the artifacts created by different spatial and temporal sampling footprints between techniques.

  6. Was the Risk from Nursing-Home Evacuation after the Fukushima Accident Higher than the Radiation Risk?

    OpenAIRE

    Michio Murakami; Kyoko Ono; Masaharu Tsubokura; Shuhei Nomura; Tomoyoshi Oikawa; Tosihiro Oka; Masahiro Kami; Taikan Oki

    2015-01-01

    After the 2011 accident at the Fukushima Daiichi nuclear power plant, nursing-home residents and staff were evacuated voluntarily from damaged areas to avoid radiation exposure. Unfortunately, the evacuation resulted in increased mortalities among nursing home residents. We assessed the risk trade-off between evacuation and radiation for 191 residents and 184 staff at three nursing homes by using the same detriment indicator, namely loss of life expectancy (LLE), under four scenarios, i.e. "r...

  7. Proceedings of the fourth JAEA-US EPA workshop on radiation risk assessment

    International Nuclear Information System (INIS)

    This report is the proceedings of the fourth workshop jointly organized by the Japan Atomic Energy Agency (JAEA) and the United States Environmental Protection Agency (US EPA) under the terms of agreement for cooperation in the field of radiation protection. The workshop was sponsored by the Nuclear Science and Engineering Directorate and was held at the Nuclear Science Research Institute, the Tokai Research and Development Center, JAEA, on November 7-8, 2006. The objective of the workshop was to exchange and discuss recent information on radiation effects, radiation risk assessment, radiation dosimetry, emergency response, radiation protection standards, and waste management. Twenty-two papers were presented by experts from JAEA, US EPA, the National Academies, Oak Ridge National Laboratory, Washington State University and the US Nuclear Regulatory Commission. Three keynotes addressed research on radiation effects and radiation protection at JAEA, the latest report on health risks from exposure to low levels of ionizing radiation published by the National Research Council (BEIR VII Phase 2), and recent developments in Committee 2 for the forthcoming recommendations of the International Commission on Radiological Protection (ICRP). The workshop provided a good opportunity for identifying future research needed for radiation risk assessment. The 22 of the presented papers are indexed individually. (J.P.N.)

  8. Risk calculations for hereditary effects of ionizing radiation in humans.

    Science.gov (United States)

    Vogel, F

    1992-05-01

    A prediction of the extent to which an additional dose of ionizing radiation increases the natural germ cell mutation rate, and how much such an increase will affect the health status of future human populations is part of the service that human geneticists are expected to offer to human society. However, more detailed scrutiny of the difficulties involved reveals an extremely complex set of problems. A large number of questions arises before such a prediction can be given with confidence; many such questions cannot be answered at our present state of knowledge. However, such predictions have recently been attempted. The 1988 report of the United Nations Scientific Committee for the Effects of Atomic Radiation and the fifth report of the Committee on Biological Effects of Ionizing Radiation of the US National Research Council have presented a discussion of the human genetics problems involved. Empirical data from studies on children of highly radiation-exposed parents, e.g. parents exposed to the atomic bombs of Hiroshima and Nagasaki, or parents belonging to populations living on soil with high background radiation, have been mentioned in this context. Whereas precise predictions are impossible as yet because of deficiencies in our knowledge of medical genetics at various levels, the bulk of the existing evidence points to only small effects of low or moderate radiation doses, effects that will probably be buried in the "background noise" of changing patterns of human morbidity and mortality. PMID:1587523

  9. Ischemic heart disease in workers at Mayak PA: latency of incidence risk after radiation exposure.

    Directory of Open Access Journals (Sweden)

    Cristoforo Simonetto

    Full Text Available We present an updated analysis of incidence and mortality from atherosclerotic induced ischemic heart diseases in the cohort of workers at the Mayak Production Association (PA. This cohort constitutes one of the most important sources for the assessment of radiation risk. It is exceptional because it comprises information on several other risk factors. While most of the workers have been exposed to external gamma radiation, a large proportion has additionally been exposed to internal radiation from inhaled plutonium. Compared to a previous study by Azizova et al. 2012, the updated dosimetry system MWDS-2008 has been applied and methods of analysis have been revised. We extend the analysis of the significant incidence risk and observe that main detrimental effects of external radiation exposure occur after more than about 30 years. For mortality, significant risk was found in males with an excess relative risk per dose of 0.09 (95% CI: 0.02; 0.16 [Formula: see text] while risk was insignificant for females. With respect to internal radiation exposure no association to risk could be established.

  10. Thermoregulation of water foraging honeybees--balancing of endothermic activity with radiative heat gain and functional requirements.

    Science.gov (United States)

    Kovac, Helmut; Stabentheiner, Anton; Schmaranzer, Sigurd

    2010-12-01

    Foraging honeybees are subjected to considerable variations of microclimatic conditions challenging their thermoregulatory ability. Solar heat is a gain in the cold but may be a burden in the heat. We investigated the balancing of endothermic activity with radiative heat gain and physiological functions of water foraging Apis mellifera carnica honeybees in the whole range of ambient temperatures (T(a)) and solar radiation they are likely to be exposed in their natural environment in Middle Europe. The mean thorax temperature (T(th)) during foraging stays was regulated at a constantly high level (37.0-38.5 °C) in a broad range of T(a) (3-30 °C). At warmer conditions (T(a)=30-39 °C) T(th) increased to a maximal level of 45.3 °C. The endothermic temperature excess (difference of T(body)-T(a) of living and dead bees) was used to assess the endogenously generated temperature elevation as a correlate of energy turnover. Up to a T(a) of ∼30 °C bees used solar heat gain for a double purpose: to reduce energetic expenditure and to increase T(th) by about 1-3 °C to improve force production of flight muscles. At higher T(a) they exhibited cooling efforts to get rid of excess heat. A high T(th) also allowed regulation of the head temperature high enough to guarantee proper function of the bees' suction pump even at low T(a). This shortened the foraging stays and this way reduced energetic costs. With decreasing T(a) bees also reduced arrival body weight and crop loading to do both minimize costs and optimize flight performance. PMID:20705071

  11. 12 CFR 615.5211 - Risk categories-balance sheet assets.

    Science.gov (United States)

    2010-01-01

    ... AFFAIRS, LOAN POLICIES AND OPERATIONS, AND FUNDING OPERATIONS Capital Adequacy § 615.5211 Risk categories... not eligible for the ratings-based approach or subject to the dollar-for-dollar capital treatment. (2... similar capital, risk identification and control, and operational standards, or (ii) Carry an...

  12. Public health safety and transplant with increased-risk organs: striking the balance.

    Science.gov (United States)

    Batra, Ramesh; Katariya, Nitin; Hewitt, Winston; Mathur, Amit; Reddy, Sudhakar; Moss, Adyr; Segev, Dorry; Singer, Andrew

    2015-04-01

    There is significant variability amongst transplant centers, Organ Procurement Organizations (OPO), members of public, and patients about organs from Public Health Service increased risk donors. This has therefore required regulatory bodies like Centers for Disease Control and Prevention to formulate policies for transplant centers and OPOs to minimize risk of infectious transmission to recipients of solid-organ transplants from such donors.

  13. Cancer incidence after retinoblastoma - Radiation dose and sarcoma risk

    NARCIS (Netherlands)

    Wong, FL; Boice, JD; Abramson, DH; Tarone, RE; Kleinerman, RA; Stovall, M; Goldman, MB; Seddon, JM; Tarbell, N; Fraumeni, JF; Li, FP

    1997-01-01

    Context.-There is a substantial risk of a second cancer for persons with hereditary retinoblastoma, which is enhanced by radiotherapy. Objective.-To examine long-term risk of new primary cancers in survivors of childhood retinoblastoma and quantify the role of radiotherapy in sarcoma development. De

  14. How safe is safe enough? Radiation risk for a human mission to Mars.

    Directory of Open Access Journals (Sweden)

    Francis A Cucinotta

    Full Text Available Astronauts on a mission to Mars would be exposed for up to 3 years to galactic cosmic rays (GCR--made up of high-energy protons and high charge (Z and energy (E (HZE nuclei. GCR exposure rate increases about three times as spacecraft venture out of Earth orbit into deep space where protection of the Earth's magnetosphere and solid body are lost. NASA's radiation standard limits astronaut exposures to a 3% risk of exposure induced death (REID at the upper 95% confidence interval (CI of the risk estimate. Fatal cancer risk has been considered the dominant risk for GCR, however recent epidemiological analysis of radiation risks for circulatory diseases allow for predictions of REID for circulatory diseases to be included with cancer risk predictions for space missions. Using NASA's models of risks and uncertainties, we predicted that central estimates for radiation induced mortality and morbidity could exceed 5% and 10% with upper 95% CI near 10% and 20%, respectively for a Mars mission. Additional risks to the central nervous system (CNS and qualitative differences in the biological effects of GCR compared to terrestrial radiation may significantly increase these estimates, and will require new knowledge to evaluate.

  15. From 'Image Gently' to image intelligently: a personalized perspective on diagnostic radiation risk

    International Nuclear Information System (INIS)

    The risk of ionizing radiation from diagnostic imaging has been a popular topic in the radiology literature and lay press. Communicating the magnitude of risk to patients and caregivers is problematic because of the uncertainty in estimates derived principally from epidemiological studies of large populations, and alternative approaches are needed to provide a scientific basis for personalized risk estimates. The underlying patient disease and life expectancy greatly influence risk projections. Research into the biological mechanisms of radiation-induced DNA damage and repair challenges the linear no-threshold dose-response assumption and reveals that individuals vary in sensitivity to radiation. Studies of decision-making psychology show that individuals are highly susceptible to irrational biases when judging risks. Truly informed medical decision-making that respects patient autonomy requires appropriate framing of radiation risks in perspective with other risks and with the benefits of imaging. To follow the principles of personalized medicine and treat patients according to their specific phenotypic and personality profiles, diagnostic imaging should optimally be tailored not only to patient size, body region and clinical indication, but also to underlying disease conditions, radio-sensitivity and risk perception and preferences that vary among individuals. (orig.)

  16. How safe is safe enough? Radiation risk for a human mission to Mars.

    Science.gov (United States)

    Cucinotta, Francis A; Kim, Myung-Hee Y; Chappell, Lori J; Huff, Janice L

    2013-01-01

    Astronauts on a mission to Mars would be exposed for up to 3 years to galactic cosmic rays (GCR)--made up of high-energy protons and high charge (Z) and energy (E) (HZE) nuclei. GCR exposure rate increases about three times as spacecraft venture out of Earth orbit into deep space where protection of the Earth's magnetosphere and solid body are lost. NASA's radiation standard limits astronaut exposures to a 3% risk of exposure induced death (REID) at the upper 95% confidence interval (CI) of the risk estimate. Fatal cancer risk has been considered the dominant risk for GCR, however recent epidemiological analysis of radiation risks for circulatory diseases allow for predictions of REID for circulatory diseases to be included with cancer risk predictions for space missions. Using NASA's models of risks and uncertainties, we predicted that central estimates for radiation induced mortality and morbidity could exceed 5% and 10% with upper 95% CI near 10% and 20%, respectively for a Mars mission. Additional risks to the central nervous system (CNS) and qualitative differences in the biological effects of GCR compared to terrestrial radiation may significantly increase these estimates, and will require new knowledge to evaluate.

  17. How safe is safe enough? Radiation risk for a human mission to Mars.

    Science.gov (United States)

    Cucinotta, Francis A; Kim, Myung-Hee Y; Chappell, Lori J; Huff, Janice L

    2013-01-01

    Astronauts on a mission to Mars would be exposed for up to 3 years to galactic cosmic rays (GCR)--made up of high-energy protons and high charge (Z) and energy (E) (HZE) nuclei. GCR exposure rate increases about three times as spacecraft venture out of Earth orbit into deep space where protection of the Earth's magnetosphere and solid body are lost. NASA's radiation standard limits astronaut exposures to a 3% risk of exposure induced death (REID) at the upper 95% confidence interval (CI) of the risk estimate. Fatal cancer risk has been considered the dominant risk for GCR, however recent epidemiological analysis of radiation risks for circulatory diseases allow for predictions of REID for circulatory diseases to be included with cancer risk predictions for space missions. Using NASA's models of risks and uncertainties, we predicted that central estimates for radiation induced mortality and morbidity could exceed 5% and 10% with upper 95% CI near 10% and 20%, respectively for a Mars mission. Additional risks to the central nervous system (CNS) and qualitative differences in the biological effects of GCR compared to terrestrial radiation may significantly increase these estimates, and will require new knowledge to evaluate. PMID:24146746

  18. Assessing risks from occupational exposure to low-level radiation

    International Nuclear Information System (INIS)

    Currently, several epidemiological studies of workers who have been exposed occupationally to radiation are being conducted. These include workers in the United States, Great Britain, and Canada, involved in the production of both defense materials and nuclear power. A major reason for conducting these studies is to evaluate possible adverse health effects that may have resulted because of the radiation exposure received. The general subject of health effects resulting from low levels of radiation, including these worker studies, has attracted the attention of various news media, and has been the subject of considerable controversy. These studies provide a good illustration of certain other aspects of the statistician's role; namely, communication and adequate subject matter knowledge. A competent technical job is not sufficient if these other aspects are not fulfilled

  19. Risks associated with low level ionizing radiation (with special reference to nuclear power workers)

    International Nuclear Information System (INIS)

    This document describes a project to use epidemiological studies of workers in the nuclear industry to estimate the cancer risk associated with low-dose chronic exposure to ionizing radiation. The project aims both to improve the basis for radiation risk assessment and to test the validity of currently used models for the extrapolation of radiation risk. This report focusses on the former aim, and summarizes discussions at two meetings held in June 1988. One of these was a small working group consisting mainly of epidemiologists who had carried out studies of nuclear workers; the other included nominees of the nuclear industries of eleven countries as well as epidemiologists and radiation physicists and biologists. As a result of the meetings, efforts are underway to pool existing data and a feasibility study is addressing the possibility of an international collaborative study of unstudied groups of nuclear workers

  20. Risks of exposure to ionizing and millimeter-wave radiation from airport whole-body scanners.

    Science.gov (United States)

    Moulder, John E

    2012-06-01

    Considerable public concern has been expressed around the world about the radiation risks posed by the backscatter (ionizing radiation) and millimeter-wave (nonionizing radiation) whole-body scanners that have been deployed at many airports. The backscatter and millimeter-wave scanners currently deployed in the U.S. almost certainly pose negligible radiation risks if used as intended, but their safety is difficult-to-impossible to prove using publicly accessible data. The scanners are widely disliked and often feared, which is a problem made worse by what appears to be a veil of secrecy that covers their specifications and dosimetry. Therefore, for these and future similar technologies to gain wide acceptance, more openness is needed, as is independent review and regulation. Publicly accessible, and preferably peer-reviewed evidence is needed that the deployed units (not just the prototypes) meet widely-accepted safety standards. It is also critical that risk-perception issues be handled more competently. PMID:22494369

  1. Communication of radiation benefits and risks in decision making: some lessons learned.

    Science.gov (United States)

    Locke, Paul A

    2011-11-01

    This paper is focused on summarizing the "lessons learned" from discussions at the 2010 NCRP Annual Meeting on effective communications on the subject of radiation benefits and risks in public exposures. Five main lessons learned are discussed in regard to effective methods of public communication: the use of new social media communication tools such as Facebook and Twitter, emergency situations that require rapid societal and personal messaging, medical radiological procedures where benefits must be described in comparison to long-term health risks of radiation exposures, and information that should be provided to stakeholders in situations such as environmental radionuclide contamination to which members of the public may be exposed. It is concluded that effective communications in which radiation benefits are contrasted with health risks of exposure are an important aspect of making and implementing decisions on employing radiation health protection procedures. PMID:21979551

  2. Radiation risk to low fluences of alpha particles may be greater than we thought.

    Science.gov (United States)

    Zhou, H; Suzuki, M; Randers-Pehrson, G; Vannais, D; Chen, G; Trosko, J E; Waldren, C A; Hei, T K

    2001-12-01

    Based principally on the cancer incidence found in survivors of the atomic bombs dropped in Hiroshima and Nagasaki, the International Commission on Radiation Protection (ICRP) and the United States National Council on Radiation Protection and Measurements (NCRP) have recommended that estimates of cancer risk for low dose exposure be extrapolated from higher doses by using a linear, no-threshold model. This recommendation is based on the dogma that the DNA of the nucleus is the main target for radiation-induced genotoxicity and, as fewer cells are directly damaged, the deleterious effects of radiation proportionally decline. In this paper, we used a precision microbeam to target an exact fraction (either 100% or making risk estimates for low dose, high linear-energy-transfer (LET) radiation exposure. PMID:11734643

  3. Study warns of radiation risk in medical imaging

    Science.gov (United States)

    Gwynne, Peter

    2009-10-01

    A study of a million US patients suggests that some who undergo medical imaging could be exposed to more ionizing radiation than those who work with radioactive materials in nuclear power plants. The study, reported in The New England Journal of Medicine (361 849), implies that current exposure to radiation from conventional X-ray equipment as well as computed tomography (CT) and positron-emission tomography (PET) scanners could lead to tens of thousands of extra cases of cancer in the US alone.

  4. How Space Radiation Risk from Galactic Cosmic Rays at the International Space Station Relates to Nuclear Cross Sections

    Science.gov (United States)

    Lin, Zi-Wei; Adams, J. H., Jr.

    2005-01-01

    Space radiation risk to astronauts is a major obstacle for long term human space explorations. Space radiation transport codes have thus been developed to evaluate radiation effects at the International Space Station (ISS) and in missions to the Moon or Mars. We study how nuclear fragmentation processes in such radiation transport affect predictions on the radiation risk from galactic cosmic rays. Taking into account effects of the geomagnetic field on the cosmic ray spectra, we investigate the effects of fragmentation cross sections at different energies on the radiation risk (represented by dose-equivalent) from galactic cosmic rays behind typical spacecraft materials. These results tell us how the radiation risk at the ISS is related to nuclear cross sections at different energies, and consequently how to most efficiently reduce the physical uncertainty in our predictions on the radiation risk at the ISS.

  5. Do changes in biomarkers from space radiation reflect dose or risk?

    Science.gov (United States)

    Brooks, A.

    The space environment is made up of many different kinds of radiation so that the proper use of biomarkers is essential to estimate radiation risk. This presentation will evaluate differences between biomarkers of dose and risk and demonstrate why they should not be confused following radiation exposures in deep space. Dose is a physical quantity, while risk is a biological quantity. Many examples exist w ereh dose or changes in biomarkers of dose are inappropriately used as predictors of risk. Without information on the biology of the system, the biomarkers of dose provide little help in predicting risk in tissues or radiation exposure types where no excess risk can be demonstrated. Many of these biomarkers of dose only reflect changes in radiation dose or exposure. However, these markers are often incorrectly used to predict risk. For example, exposure of the trachea or of the deep lung to high-LET alpha particles results in similar changes in the biomarker chromosome damage in these two tissues. Such an observation would predict that the risk for cancer induction would be similar in these two tissues. It has been noted , however, that there has never been a tracheal tumor observed in rats that inhaled radon, but with the same exposure, large numbers of tumors were produced in the deep lung. The biology of the different tissues is the major determinant of the risk rather than the radiation dose. Recognition of this fact has resulted in the generation of tissue weighting factors for use in radiation protection. When tissue weighting factors are used the values derived are still called "dose". It is important to recognize that tissue specific observations have been corrected to reflect risk, and therefore should no longer be viewed as dose. The relative biological effectiveness (RBE) is also used to estimate radiation risk. The use of biomarkers to derive RBE is a difficult since it involves the use of a biological response to a standard low-LET reference radiation

  6. Radiation risks and work-up strategies of detected lesions

    International Nuclear Information System (INIS)

    Groups of women who received extremely high doses of radiation (100 to over 1000 rads) to the breast have shown as excess number breast cancers when compared with comparable groups on nonexposed women. These high-dose groups include Japanese survivors of the atomic bombings at Hiroshima and Nagasaki, women treated with radiation therapy in 1920s for benign breast conditions such as post partum mastitis or received multiple chest fluoroscopies after tuberculosis treated with artificial pneumothorax therapy. Not known is whether very low doses of radiation can also be carcinogenic. The low doses used in mammography techniques are all far below one rad. Mean breast dose for a two-view exposure is 0.1 rad and even using a grid, it is still less than 0.2 rad. It is slightly higher for Xeromammography, which is in fact in decreasing use in the USA. Only a minority of examinations, perhaps 20%, are still conducted on Xeromammography. The dose is about 0.5 rad for the Xeron negative mode technique and 0.25 rad for the new Xerox liquid toner system. In any event, all these doses are extremely low and several orders of magnitude lower than the doses at which radiation carcinogenesis has been demonstrated. (author). 7 refs., 1 fig., 3 tabs

  7. Attitudes of Kuwaiti public towards the radiation risks of nuclear medicine diagnositic procedures

    International Nuclear Information System (INIS)

    Public perception of radiation risks of diagnostic imaging procedures differs from that of professionals working in the field. The perception probably varies among societies and may vary within the same society. The objective of this study is to determine the public perception in Kuwait represented by patients referred for nuclear medicine diagnostic studies. With the assistance of Arabic speaking investigators, 239 patients (139 males and 100 females) with a mean age of 37 years (Range of 15 to 90 years) completed a questionnaire about their opinion of radiation fear from the nuclear medicine procedures as well as their education, income, ability to speak English and foreign travel experience. Radiation phobia was measured by asking the patient to to the statement 'Radiation from nuclear medicine examination is likely to harm my body' by one of 5 choices, 1 strongly agree, 2 somewhat agree, 3 uncertain, 4 somewhat disagree, 5 strongly disagree. Responses 1 and 2 were classified as radiation phobia. Pearson correlation coefficient and logistic regression analysis were used for data analysis. Forty four percent of patients had radiation phobia. Only education significantly correlated with radiation phobia. Income, ability to speak English, age, gender or travel experience did not show significant correlation. Our study indicates that radiation phobia is common and is probably widespread throughout the society. Patient education should emphasize radiation benefits and actual risks and include the entire community. (authors)

  8. Risk based or biased contaminated land management: conceptual clarifications for more comprehensive and balanced views and policies

    Energy Technology Data Exchange (ETDEWEB)

    Assmuth, T.W. [Finnish Environ Inst. (SYKE), Helsinki (Finland)

    2003-07-01

    I present a critical socio-psychological, communication-oriented, political and philosophical framework and analysis of some problematic aspects and statements in the professional discussion on the socalled Risk Based Land Management (RBLM) concept and of its contexts, foundations, limitations and implications. I put particular emphasis on a) questions and challenges in the broadened scope implicit in RBLM, from immediate hotspot contaminant control to long-term management of extensive areas and resources pressured by several risk agents not restricted to chemicals; b) multidimensionality of risks and uncertainties; and c) balancing the justified roles of RBLM with a critique of the vague and rigid uses of this and related concepts as an euphemism and a disguise to distort risks and associated uncertainties and also to influence management goals and principles. I address specifically the use of RBLM as an idealized (and idolized) panacea and as an alleged or implied herald of greater realism and scientific basis in comparison with other approaches. Throughout the work, I investigate the modes of perceiving risks and uncertainties, and reasoning and communicating about them and their management, as intertwined elements based on both facts and values in a knowledge-related but also otherwise conditioned social process. In the general conceptual analysis, I outline important contexts, parts and relationships between R, M and L (and contamination) in this particular case, focusing on possibilities for introduction (and avoidance) of narrow and biased views, and illuminating especially the connections between risks and benefits in assessment and management. I then proceed to a general exposition of confusing and controversial notions of 'Risk Based' in this and closely related areas of (environmental, health and chemicals) management. (orig.)

  9. Risk-Informed Balancing Of Safety, Nonproliferation, And Economics For The SFR

    International Nuclear Information System (INIS)

    A substantial barrier to the implementation of Sodium-cooled Fast Reactor (SFR) technology in the short term is the perception that they would not be economically competitive with advanced light water reactors. With increased acceptance of risk-informed regulation, the opportunity exists to reduce the costs of a nuclear power plant at the design stage without applying excessive conservatism that is not needed in treating low risk events. In the report, NUREG-1860, the U.S. Nuclear Regulatory Commission describes developmental activities associated with a risk-informed, scenario-based technology neutral framework (TNF) for regulation. It provides quantitative yardsticks against which the adequacy of safety risks can be judged. We extend these concepts to treatment of proliferation risks. The objective of our project is to develop a risk-informed design process for minimizing the cost of electricity generation within constraints of adequate safety and proliferation risks. This report describes the design and use of this design optimization process within the context of reducing the capital cost and levelized cost of electricity production for a small (possibly modular) SFR. Our project provides not only an evaluation of the feasibility of a risk-informed design process but also a practical test of the applicability of the TNF to an actual advanced, non-LWR design. The report provides results of five safety related and one proliferation related case studies of innovative design alternatives. Applied to previously proposed SFR nuclear energy system concepts We find that the TNF provides a feasible initial basis for licensing new reactors. However, it is incomplete. We recommend improvements in terms of requiring acceptance standards for total safety risks, and we propose a framework for regulation of proliferation risks. We also demonstrate methods for evaluation of proliferation risks. We also suggest revisions to scenario-specific safety risk acceptance standards

  10. RISK-INFORMED BALANCING OF SAFETY, NONPROLIFERATION, AND ECONOMICS FOR THE SFR

    Energy Technology Data Exchange (ETDEWEB)

    Apostolakis, George; Driscoll, Michael; Golay, Michael; Kadak, Andrew; Todreas, Neil; Aldmir, Tunc; Denning, Richard; Lineberry, Michael

    2011-10-20

    A substantial barrier to the implementation of Sodium-cooled Fast Reactor (SFR) technology in the short term is the perception that they would not be economically competitive with advanced light water reactors. With increased acceptance of risk-informed regulation, the opportunity exists to reduce the costs of a nuclear power plant at the design stage without applying excessive conservatism that is not needed in treating low risk events. In the report, NUREG-1860, the U.S. Nuclear Regulatory Commission describes developmental activities associated with a risk-informed, scenario-based technology neutral framework (TNF) for regulation. It provides quantitative yardsticks against which the adequacy of safety risks can be judged. We extend these concepts to treatment of proliferation risks. The objective of our project is to develop a risk-informed design process for minimizing the cost of electricity generation within constraints of adequate safety and proliferation risks. This report describes the design and use of this design optimization process within the context of reducing the capital cost and levelized cost of electricity production for a small (possibly modular) SFR. Our project provides not only an evaluation of the feasibility of a risk-informed design process but also a practical test of the applicability of the TNF to an actual advanced, non-LWR design. The report provides results of five safety related and one proliferation related case studies of innovative design alternatives. Applied to previously proposed SFR nuclear energy system concepts We find that the TNF provides a feasible initial basis for licensing new reactors. However, it is incomplete. We recommend improvements in terms of requiring acceptance standards for total safety risks, and we propose a framework for regulation of proliferation risks. We also demonstrate methods for evaluation of proliferation risks. We also suggest revisions to scenario-specific safety risk acceptance standards

  11. Risk Analysis of the Romanian Banking System – an Aggregated Balance Sheet Approach

    Directory of Open Access Journals (Sweden)

    Eugen MITRICA

    2010-12-01

    Full Text Available The paper presents a risk analysis for the current Romanian banking system. The analysis is conducted from the point of view of prudential rules and also from the point of view of Romanian banking system’s exposure to foreign funds, considering the consequences of these features, concerning the soundness and reliability of the banking system. The analysis found a manageable risk level, apparently, although during 2009 and 2010 the expansion of risk indicators was accelerated, but finally, in the late 2010, there are some signs of stabilization. The exposure of Romanian banking system to foreign funds was another important risk source. The exposure to foreign funds had an important decrease during 2009, but in 2010 it seems to stabilize.

  12. The Risks of Off-Balance Sheet Derivatives in U.S. Commercial Banks

    OpenAIRE

    M Kabir Hassan; Ahmad Khasawneh

    2009-01-01

    This study employs both contingent and non-contingent claim models to test for the existence of market discipline hypothesis for derivative contracts in U.S. banking industry. In addition to the Capital Asset Pricing Model (CAPM) measure of systematic risk and standard deviation of a bank’s equity return, we apply Ronn-Verma option pricing model to assess whether market participants incorporate derivatives positions when they price banks’ market risk. The benefit of using the contingent claim...

  13. Safety and radiation risks in the labelling of blood cells

    International Nuclear Information System (INIS)

    Risk in the management of radioactive material and biological exposition to infectious agents. Protocols and normative to observe GOOD RADIOPHARMACY Practices. Main infectious agents that may be transmitted during preparation of a blood cell radiopharmaceutical. Problems of contamination

  14. Space Radiation Cancer Risks and Uncertainities for Different Mission Time Periods

    Science.gov (United States)

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

    2012-01-01

    Space radiation consists of solar particle events (SPEs), comprised largely of medium energy protons (less than several hundred MeV); and galactic cosmic ray (GCR), which includes high energy protons and high charge and energy (HZE) nuclei. For long duration missions, space radiation presents significant health risks including cancer mortality. Probabilistic risk assessment (PRA) is essential for radiation protection of crews on long term space missions outside of the protection of the Earth s magnetic field and for optimization of mission planning and costs. For the assessment of organ dosimetric quantities and cancer risks, the particle spectra at each critical body organs must be characterized. In implementing a PRA approach, a statistical model of SPE fluence was developed, because the individual SPE occurrences themselves are random in nature while the frequency distribution of SPEs depends strongly upon the phase within the solar activity cycle. Spectral variability of SPEs was also examined, because the detailed energy spectra of protons are important especially at high energy levels for assessing the cancer risk associated with energetic particles for large events. An overall cumulative probability of a GCR environment for a specified mission period was estimated for the temporal characterization of the GCR environment represented by the deceleration potential (theta). Finally, this probabilistic approach to space radiation cancer risk was coupled with a model of the radiobiological factors and uncertainties in projecting cancer risks. Probabilities of fatal cancer risk and 95% confidence intervals will be reported for various periods of space missions.

  15. Cancer risk in diagnostic radiation workers in Korea from 1996–2002.

    Science.gov (United States)

    Choi, Kyung-Hwa; Ha, Mina; Lee, Won Jin; Hwang, Seung-Sik; Jeong, Meeseon; Jin, Young-Woo; Kim, Hyeog Ju; Lee, Kwang-Yong; Lee, Jung-Eun; Kang, Jong-Won; Kim, Heon

    2013-01-14

    This study was aimed to examine the association between the effective radiation dose of diagnostic radiation workers in Korea and their risk for cancer. A total of 36,394 diagnostic radiation workers (159,189 person-years) were included in this study; the effective dose and cancer incidence were analyzed between the period 1996 and 2002. Median (range) follow-up time was 5.5 (0.04-7) years in males and 3.75 (0.04-7) years in females. Cancer risk related to the average annual effective dose and exposure to more than 5 mSv of annual radiation dose were calculated by the Cox proportional hazard model adjusted for occupation and age at the last follow-up. The standardized incidence ratio of cancer in radiation workers showed strong healthy worker effects in both male and female workers. The relative risk of all cancers from exposure of the average annual effective dose in the highest quartile (upper 75% or more of radiation dose) was 2.14 in male workers (95% CI: 1.48-3.10, p-trend: <0.0001) and 4.43 in female workers (95% CI: 2.17-9.04, p-trend: <0.0001), compared to those in the lower three quartiles of radiation exposure dose (less than upper 75% of radiation dose). Cancer risks of the brain (HR: 17.38, 95% CI: 1.05-287.8, p-trend: 0.04) and thyroid (HR: 3.88, 95% CI: 1.09-13.75, p-trend: 0.01) in female workers were significantly higher in the highest quartile group of radiation exposure compared to those in the lower three quartiles, and the risk of colon and rectum cancers in male workers showed a significantly increasing trend according to the increase of the average annual radiation dose (HR: 2.37, 95% CI: 0.99-5.67, p-trend: 0.02). The relative risk of leukemia in male workers and that of brain cancer in female workers were significantly higher in the group of people who had been exposed to more than 5 mSv/year than those exposed to less than 5 mSv/year (HR: 11.75, 95% CI: 1.08-128.20; HR: 63.11, 95% CI: 3.70-1,075.00, respectively). Although the present study

  16. Component greenhouse gas fluxes and radiative balance from two deltaic marshes in Louisiana: Pairing chamber techniques and eddy covariance

    Science.gov (United States)

    Krauss, Ken W.; Holm, Guerry O.; Perez, Brian C.; McWhorter, David E.; Cormier, Nicole; Moss, Rebecca; Johnson, Darren; Neubauer, Scott C; Raynie, Richard C

    2016-01-01

    Coastal marshes take up atmospheric CO2 while emitting CO2, CH4, and N2O. This ability to sequester carbon (C) is much greater for wetlands on a per-area basis than from most ecosystems, facilitating scientific, political, and economic interest in their value as greenhouse gas sinks. However, the greenhouse gas balance of Gulf of Mexico wetlands is particularly understudied. We describe the net ecosystem exchange (NEEc) of CO2 and CH4 using eddy covariance (EC) in comparison with fluxes of CO2, CH4, and N2O using chambers from brackish and freshwater marshes in Louisiana, USA. From EC, we found that 182 g C m-2 y-1 was lost through NEEc from the brackish marsh. Of this, 11 g C m-2 y-1 resulted from net CH4 emissions and the remaining 171 g C m-2 y-1 resulted from net CO2 emissions. In contrast, -290 g C m2 y-1 was taken up through NEEc by the freshwater marsh, with 47 g C m-2 y-1 emitted as CH4 and -337 g C m-2 y-1 taken up as CO2. From chambers, we discovered that neither site had large fluxes of N2O. Sustained-flux greenhouse gas accounting metrics indicated that both marshes had a positive (warming) radiative balance, with the brackish marsh having a substantially greater warming effect than the freshwater marsh. That net respiratory emissions of CO2 and CH4 as estimated through chamber techniques were 2-4 times different from emissions estimated through EC requires additional understanding of the artifacts created by different spatial and temporal sampling footprints between techniques.

  17. Comparison of radiation exposure and associated radiation-induced cancer risks from mammography and molecular imaging of the breast

    International Nuclear Information System (INIS)

    Purpose: Recent studies have raised concerns about exposure to low-dose ionizing radiation from medical imaging procedures. Little has been published regarding the relative exposure and risks associated with breast imaging techniques such as breast specific gamma imaging (BSGI), molecular breast imaging (MBI), or positron emission mammography (PEM). The purpose of this article was to estimate and compare the risks of radiation-induced cancer from mammography and techniques such as PEM, BSGI, and MBI in a screening environment. Methods: The authors used a common scheme for all estimates of cancer incidence and mortality based on the excess absolute risk model from the BEIR VII report. The lifetime attributable risk model was used to estimate the lifetime risk of radiation-induced breast cancer incidence and mortality. All estimates of cancer incidence and mortality were based on a population of 100 000 females followed from birth to age 80 and adjusted for the fraction that survives to various ages between 0 and 80. Assuming annual screening from ages 40 to 80 and from ages 50 to 80, the cumulative cancer incidence and mortality attributed to digital mammography, screen-film mammography, MBI, BSGI, and PEM was calculated. The corresponding cancer incidence and mortality from natural background radiation was calculated as a useful reference. Assuming a 15%-32% reduction in mortality from screening, the benefit/risk ratio for the different imaging modalities was evaluated. Results: Using conventional doses of 925 MBq Tc-99m sestamibi for MBI and BSGI and 370 MBq F-18 FDG for PEM, the cumulative cancer incidence and mortality were found to be 15-30 times higher than digital mammography. The benefit/risk ratio for annual digital mammography was >50:1 for both the 40-80 and 50-80 screening groups, but dropped to 3:1 for the 40-49 age group. If the primary use of MBI, BSGI, and PEM is in women with dense breast tissue, then the administered doses need to be in the range

  18. Technologically enhanced natural radiation and the significance of related risks

    International Nuclear Information System (INIS)

    Technologically enhanced natural radiation (TENR) is the result of a wide range of industrial activities, such as: non-nuclear energy production, manufacturing, and ore extraction and refining. In addition, recycling of industrial wastes (e.g. phosphogypsum, fly-ash) as construction material, special architectural characteristics (e.g. energy-efficient solar homes) and specific used (e.g. mineral storage by collectors) can cause an increased radiation exposure to workers and members of the public. The total collective effective dose equivalent commitment (CDEC) from the TENR on a global scale in about 400,000 man Sv per year of practice, predominantly due to the impact of the phosphate fertilizer industry. This is equivalent to about 140-times the CDEC resulting from the present complete nuclear fuel cycle worldwide. (author). 43 refs, 5 figs, 5 tabs

  19. Radiation and society: Comprehending radiation risk. V. 1. A report to the IAEA with collected papers. Proceedings of an international conference

    International Nuclear Information System (INIS)

    The report includes 10 papers prepared by the Swedish Risk Academy for the IAEA Conference on Radiation and Society: Comprehending Radiation Risk, held in Paris between 24-28 October 1994. A separate abstract was prepared for each paper. Refs, figs and tabs

  20. Evidence Report: Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure

    Science.gov (United States)

    Patel, Zarana; Huff, Janice; Saha, Janapriya; Wang, Minli; Blattnig, Steve; Wu, Honglu; Cucinotta, Francis

    2015-01-01

    Occupational radiation exposure from the space environment may result in non-cancer or non-CNS degenerative tissue diseases, such as cardiovascular disease, cataracts, and respiratory or digestive diseases. However, the magnitude of influence and mechanisms of action of radiation leading to these diseases are not well characterized. Radiation and synergistic effects of radiation cause DNA damage, persistent oxidative stress, chronic inflammation, and accelerated tissue aging and degeneration, which may lead to acute or chronic disease of susceptible organ tissues. In particular, cardiovascular pathologies such as atherosclerosis are of major concern following gamma-ray exposure. This provides evidence for possible degenerative tissue effects following exposures to ionizing radiation in the form of the GCR or SPEs expected during long-duration spaceflight. However, the existence of low dose thresholds and dose-rate and radiation quality effects, as well as mechanisms and major risk pathways, are not well-characterized. Degenerative disease risks are difficult to assess because multiple factors, including radiation, are believed to play a role in the etiology of the diseases. As additional evidence is pointing to lower, space-relevant thresholds for these degenerative effects, particularly for cardiovascular disease, additional research with cell and animal studies is required to quantify the magnitude of this risk, understand mechanisms, and determine if additional protection strategies are required.The NASA PEL (Permissive Exposure Limit)s for cataract and cardiovascular risks are based on existing human epidemiology data. Although animal and clinical astronaut data show a significant increase in cataracts following exposure and a reassessment of atomic bomb (A-bomb) data suggests an increase in cardiovascular disease from radiation exposure, additional research is required to fully understand and quantify these adverse outcomes at lower doses (less than 0.5 gray

  1. Radiation-related risks of non-cancer outcomes in the atomic bomb survivors.

    Science.gov (United States)

    Ozasa, K; Takahashi, I; Grant, E J

    2016-06-01

    Risks of non-cancer outcomes after exposure to atomic bomb (A-bomb) radiation have been evaluated among the Life Span Study (LSS) cohort and its subcohort, the Adult Health Study (AHS). Information regarding non-cancer outcomes in the LSS is obtained from death certificates. In the AHS, members undergo clinical examinations biennially to determine their health status. Many AHS studies have been limited to participants attending the clinic over a limited period, and therefore have varying degrees of inferential utility; as such, care is required for comparison with the LSS results. Disease structure of non-cancer diseases in Japan has changed over the long follow-up period since the end of World War II. The health status of the A-bomb survivors may be associated with the hardships of living in a devastated city and impoverished country following the prolonged war effort, in addition to the direct effects of radiation exposure. Radiation-related risk of cardiovascular disease may have increased due to radiation-related increased risk of hypertension and other secondary associations, and the risk of atherosclerotic disorders has also been reported recently. These results should be interpreted with caution because of changes in disease definitions over the follow-up period. The radiation-related risk of non-cancer respiratory diseases also appears to have increased over the follow-up period, but the shapes of the dose-response curves have shown little consistency. PMID:26956675

  2. Radiation balance of coffee hedgerows Balanço de radiação de renques de cafeeiros

    Directory of Open Access Journals (Sweden)

    Luiz R. Angelocci

    2008-06-01

    Full Text Available The radiation balance of hedgerows is an important variable in studies of mass and energy exchanges between parcial ground cover crops and the atmosphere. This paper describes a device with eight net radiometers encompassing the plants of a hedgerow. The radiometers were moved along a length of hedgerow, in a continuous and reversible movement. The canopy net radiation in this length (Rnc was found by integration of the measurements over the notional cylinder formed. The device showed good performance and provided reliable measurements of Rnc of coffee hedgerows, showing itselfto be an useful technique of measurement in field conditions. Good correlations between Rnc and global solar radiation, turfgrass and coffee crop net radiation were found in 15-min, daytime and 24-hr periods, allowing the possibility of estimating Rnc from these simple measurements. Beer’s law was also used to have an independent estimation of Rnc. A good agreement was found between values of Rnc estimated by this law of attenuation and those integrated by the device in periods of 15 min, with overestimation of 10%, whereas for values integrated over daytime periods the agreement was not satisfactory.A radiação, tanto de ondas curtas como de ondas longas, absorvida por um renque de plantas de uma cultura que cobre de forma descontínua o solo, é uma variável importante para os estudos das trocas de massa e de energia com a atmosfera. Este trabalho apresenta um dispositivo que movimenta oito saldo-radiômetros dispostos em torno de um renque. O movimento de ida e volta ao longo de um trecho de um renque, permite a integração do saldo de radiação na superfície de um cilindro nocional de medidas, representando o balanço de radiação (Rnc do trecho amostrado. O equipamento apresentou um bom desempenho quando empregado em dois cafezais, mostrando potencial para a realização de medidas de campo, com valores medidos confiáveis. Foram obtidas boas correla

  3. Perception and acceptance of risk from radiation exposure in space flight

    International Nuclear Information System (INIS)

    There are a number of factors that influence how a person views a particular risk. These include whether the risk is judged to be voluntary and/or controllable, whether the effects are immediate or delayed, and the magnitude of the benefits that are to be gained as a result of being exposed to the risk. An important aspect of the last factor is whether those who suffer the risks are also those who stand to reap the benefits. The manner in which risk is viewed is also significantly influenced by the manner in which it is framed and presented. In short, risk does not exist in the world independent of our minds and cultures, waiting to be measured. Assessments of risk are based on models whose structure is subjective and associated evaluations are laden with assumptions whose inputs are dependent on judgments. In fact, subjectivity permeates every aspect of risk assessment. The assessment of radiation risks in space is no exception. The structuring of the problem includes judgments related to the probability, magnitude, and effects of the various types of radiation likely to be encountered and assumptions related to the quantitative relationship between dose and a range of specific effects, all of which have associated uncertainties. For these reasons, there is no magic formula that will lead us to a precise level of acceptable risk from exposure to radiation in space. Acceptable risk levels must evolve through a process of negotiation that integrates a large number of social, technical, and economic factors. In the end, a risk that is deemed to be acceptable will be the outgrowth of the weighing of risks and benefits and the selection of the option that appears to be best

  4. Perception and acceptance of risk from radiation exposure in space flight

    Energy Technology Data Exchange (ETDEWEB)

    Slovic, P.

    1997-04-30

    There are a number of factors that influence how a person views a particular risk. These include whether the risk is judged to be voluntary and/or controllable, whether the effects are immediate or delayed, and the magnitude of the benefits that are to be gained as a result of being exposed to the risk. An important aspect of the last factor is whether those who suffer the risks are also those who stand to reap the benefits. The manner in which risk is viewed is also significantly influenced by the manner in which it is framed and presented. In short, risk does not exist in the world independent of our minds and cultures, waiting to be measured. Assessments of risk are based on models whose structure is subjective and associated evaluations are laden with assumptions whose inputs are dependent on judgments. In fact, subjectivity permeates every aspect of risk assessment. The assessment of radiation risks in space is no exception. The structuring of the problem includes judgments related to the probability, magnitude, and effects of the various types of radiation likely to be encountered and assumptions related to the quantitative relationship between dose and a range of specific effects, all of which have associated uncertainties. For these reasons, there is no magic formula that will lead us to a precise level of acceptable risk from exposure to radiation in space. Acceptable risk levels must evolve through a process of negotiation that integrates a large number of social, technical, and economic factors. In the end, a risk that is deemed to be acceptable will be the outgrowth of the weighing of risks and benefits and the selection of the option that appears to be best.

  5. Radiation in the workplace-a review of studies of the risks of occupational exposure to ionising radiation

    Energy Technology Data Exchange (ETDEWEB)

    Wakeford, Richard [Dalton Nuclear Institute, The University of Manchester, Pariser Building-G Floor, PO Box 88, Sackville Street, Manchester M60 1QD (United Kingdom)], E-mail: Richard.Wakeford@manchester.ac.uk

    2009-06-01

    Many individuals are, or have been, exposed to ionising radiation in the course of their work and the epidemiological study of occupationally irradiated groups offers an important opportunity to complement the estimates of risks to health resulting from exposure to radiation that are obtained from other populations, such as the Japanese survivors of the atomic bombings of Hiroshima and Nagasaki in 1945. Moreover, workplace exposure to radiation usually involves irradiation conditions that are of direct relevance to the principal concern of radiological protection: protracted exposure to low level radiation. Further, some workers have been exposed to radioactive material that has been inadvertently taken into the body, and the study of these groups leads to risk estimates derived directly from the experience of those irradiated by these 'internal emitters', intakes of {alpha}-particle-emitters being of particular interest. Workforces that have been the subject of epidemiological study include medical staff, aircrews, radium dial luminisers, underground hard-rock miners, Chernobyl clean-up workers, nuclear weapons test participants and nuclear industry workers. The first solid epidemiological evidence of the stochastic effects of irradiation came from a study of occupational exposure to medical x-rays that was reported in 1944, which demonstrated a large excess risk of leukaemia among US radiologists; but the general lack of dose records for early medical staff who tended to experience the highest exposures hampers the derivation of risks per unit dose received by medical workers. The instrument dial luminisers who inadvertently ingested large amounts of radium-based paint and underground hard-rock miners who inhaled large quantities of radon and its decay products suffered markedly raised excess risks of, respectively, bone and lung cancers; the miner studies have provided standard risk estimates for radon-induced lung cancer. The large numbers of nuclear

  6. Radiation in the workplace-a review of studies of the risks of occupational exposure to ionising radiation.

    Science.gov (United States)

    Wakeford, Richard

    2009-06-01

    Many individuals are, or have been, exposed to ionising radiation in the course of their work and the epidemiological study of occupationally irradiated groups offers an important opportunity to complement the estimates of risks to health resulting from exposure to radiation that are obtained from other populations, such as the Japanese survivors of the atomic bombings of Hiroshima and Nagasaki in 1945. Moreover, workplace exposure to radiation usually involves irradiation conditions that are of direct relevance to the principal concern of radiological protection: protracted exposure to low level radiation. Further, some workers have been exposed to radioactive material that has been inadvertently taken into the body, and the study of these groups leads to risk estimates derived directly from the experience of those irradiated by these 'internal emitters', intakes of alpha-particle-emitters being of particular interest. Workforces that have been the subject of epidemiological study include medical staff, aircrews, radium dial luminisers, underground hard-rock miners, Chernobyl clean-up workers, nuclear weapons test participants and nuclear industry workers. The first solid epidemiological evidence of the stochastic effects of irradiation came from a study of occupational exposure to medical x-rays that was reported in 1944, which demonstrated a large excess risk of leukaemia among US radiologists; but the general lack of dose records for early medical staff who tended to experience the highest exposures hampers the derivation of risks per unit dose received by medical workers. The instrument dial luminisers who inadvertently ingested large amounts of radium-based paint and underground hard-rock miners who inhaled large quantities of radon and its decay products suffered markedly raised excess risks of, respectively, bone and lung cancers; the miner studies have provided standard risk estimates for radon-induced lung cancer. The large numbers of nuclear industry

  7. Computer-aided methods for evaluating cancer risk in miners due to radiation exposure

    International Nuclear Information System (INIS)

    The paper presents some aspects of radiation hazard which occurs in a non-nuclear sector of industry, namely radiation hazard in non-uranium underground mines. The radiation hazard is caused in each type of underground mine by the naturally occurring noble radioactive gas-radon (222Rn) and radioactive products of its decay 218Po, 214Pb, 214Bi/214Po the so-called 'radon daughters' occurring in the mines' air. The paper presents the concept of how to provide a reliable system of assessment of miners' exposure by application of representative individual dosimetry, and also presents principles of computer-aided methods for interpretation of the results of miner's dosimetry useful for conversion of dosimetry data to the term of expected risk of cancer caused by exposure at miner's workplaces. The representative Individual Dosimetry system strengthened by computer-aided methods of analysis of results provided essential information on radiation cancer risk for miners employed in coal mines, metal-ore mines, chemical raw material mines in Poland. The coefficient of annual cancer risk induction is 1.5 x 10-4 year-1 for coal mines, 1.40 x 10-4 year-1 for metal ore mines and 1.5 x 10-4 year-1 for chemical raw material mines. The radiation risk appears to be of the same magnitude as the conventional risk of life loss at work-related accidents. The average Lost Life Expectancy coefficient for both the radiation risk and conventional risk are 0.5 and 0.3 year per each miner, respectively. (author)

  8. Computer-aided methods for evaluating cancer risk in miners due to radiation exposure.

    Science.gov (United States)

    Domański, T; Kluszczyński, D; Chruścielewski, W; Olszewski, J

    1993-01-01

    The paper presents some aspects of radiation hazard which occurs in a non-nuclear sector of industry, namely radiation hazard in non-uranium underground mines. The radiation hazard is caused in each type of underground mine by the naturally occurring noble radioactive gas-radon (222Rn) and radioactive products of its decay 218Po, 214Pb, 214Bi/214Po the so-called 'radon daughters' occurring in the mines' air. The paper presents the concept of how to provide a reliable system of assessment of miners' exposure by application of representative individual dosimetry, and also presents principles of computer-aided methods for interpretation of the results of miner's dosimetry useful for conversion of dosimetry data to the term of expected risk of cancer caused by exposure at miner's workplaces. The representative Individual Dosimetry system strengthened by computer-aided methods of analysis of results provided essential information on radiation cancer risk for miners employed in coal mines, metal-ore mines, chemical raw material mines in Poland. The coefficient of annual cancer risk induction is 1.5 x 10(-4) year-1 for coal mines, 1.40 x 10(-4) year-1 for metal ore mines and 1.5 x 10(-4) year-1 for chemical raw material mines. The radiation risk appears to be of the same magnitude as the conventional risk of life loss at work-related accidents. The average Lost Life Expectancy coefficient for both the radiation risk and conventional risk are 0.5 and 0.3 year per each miner, respectively. PMID:8019199

  9. [Risk analysis in radiation therapy: state of the art].

    Science.gov (United States)

    Mazeron, R; Aguini, N; Deutsch, É

    2013-01-01

    Five radiotherapy accidents, from which two serial, occurred in France from 2003 to 2007, led the authorities to establish a roadmap for securing radiotherapy. By analogy with industrial processes, a technical decision form the French Nuclear Safety Authority in 2008 requires radiotherapy professionals to conduct analyzes of risks to patients. The process of risk analysis had been tested in three pilot centers, before the occurrence of accidents, with the creation of cells feedback. The regulation now requires all radiotherapy services to have similar structures to collect precursor events, incidents and accidents, to perform analyzes following rigorous methods and to initiate corrective actions. At the same time, it is also required to conduct analyzes a priori, less intuitive, and usually require the help of a quality engineer, with the aim of reducing risk. The progressive implementation of these devices is part of an overall policy to improve the quality of radiotherapy. Since 2007, no radiotherapy accident was reported. PMID:23787020

  10. Balancing Caution and Greed: Neurometric Responses to Decision-Making under Escalating Risk

    DEFF Research Database (Denmark)

    Meder, David; Haagensen, Brian Numelin; Morville, Tobias;

    Introduction: Across a diversity of environments from foraging to financial investment, agents face escalating potential reward and risk (the first being the motivation for accepting the second) and need to retrieve relevant information from the environment in order to update which action to take...... seen in left inferior temporal gyrus, left and right superior frontal gyri, and left putamen. Conclusions: The above analysis afforded opportunity to distinguish three variables, pertaining to the sequential trade-off of risk and reward produced by consecutive outcomes when repeatedly throwing a die...

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Uncertainties due to soil data in Flood Risk Forecasts with the Water Balance Model LARSIM

    Science.gov (United States)

    Mitterer, Johannes

    2016-04-01

    Reliable flood forecasts with quantitative statements about contained uncertainties are essential for far reaching decisions in disaster management. In this paper uncertainties resulting from soil data are analysed for the in the German-speaking world widely used water balance model LARSIM and quantified as far as possible. At the beginning a structural and statistical analysis about the wittingly simple designed soil module is performed. It consists of a storage volume with four separate runoff components only defined by the storage size. Additionally, the model structure is examined with regard to effects of uncertain soil data using a soil map from the Bavarian State Institute for Forestry which already contains estimated minimum and maximum values for important soil parameters. For further analysis, two German catchments in Upper Franconia located at the White Main with a size of 250 km² each, covering a huge variety of soil types are used as case examples. Skeleton is identified as an important source of uncertainty in soil data comparing the quantifiable information of available soil maps and using field and laboratory analysis. Furthermore, surface runoff and fast interflow fluxes show up to be sensitive for peaks of flood events, whereas slow interflow and base flow fluxes have smaller and more long term effects on discharges and the water balance. A reduction of the soil storage basically leads to a more intensified reaction of discharges than an enlargement. The calculation of two extreme scenarios within the statistical analysis result in simulated gage measurements varying from -42 % till +218 % compared to the scenario with the main value of the map. A percental variation of the soil storage shows a doubling of the flood discharges, if the storage size is halved and a reduction up to 20% using a doubled one. Finally, a Monte Carlo Simulation is performed using the statistical data of the soil map combined with a normal distribution, whereby the

  13. The carcinogenic risks of low-LET and high-LET ionizing radiations

    International Nuclear Information System (INIS)

    This report presents a discussion on risk from ionizing radiations to human populations. Important new information on human beings has come mainly from further follow-up of existing epidemiological studies, notably the Japanese atomic bomb survivors and the ankylosing spondylitis patients; from new epidemiological surveys, such as the patients treated for cancer of the uterine cervix; and from combined surveys, including workers exposed in underground mines. Since the numerous and complex differences among the different study populations introduce factors that influence the risk estimates derived in ways that are not completely understood, it is not clear how to combine the different risk estimates obtained. These factors involve complex biological and physical variables distributed over time. Because such carcinogenic effects occur too infrequently to be demonstrated at low doses, the risks of low-dose radiation can be estimated only by interpolation from observations at high doses on the basis of theoretical concepts, mathematical models and available empirical evidence, primarily the epidemiological surveys of large populations exposed to ionizing radiation. In spite of a considerable amount of research, only recently has there has been efforts to apply the extensive laboratory data in animals to define the dose-incidence relationship in the low dose region. There simply are insufficient data in the epidemiological studies of large human populations to estimate risk coefficients directly from exposure to low doses. The risk estimates for the carcinogenic effects of radiation have been, in the past, somewhat low and reassessment of the numerical values is now necessary

  14. The carcinogenic risks of low-LET and high-LET ionizing radiations. Revision

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I. [Lawrence Berkeley Lab., CA (United States)]|[California Univ., San Francisco, CA (United States)

    1991-08-01

    This report presents a discussion on risk from ionizing radiations to human populations. Important new information on human beings has come mainly from further follow-up of existing epidemiological studies, notably the Japanese atomic bomb survivors and the ankylosing spondylitis patients; from new epidemiological surveys, such as the patients treated for cancer of the uterine cervix; and from combined surveys, including workers exposed in underground mines. Since the numerous and complex differences among the different study populations introduce factors that influence the risk estimates derived in ways that are not completely understood, it is not clear how to combine the different risk estimates obtained. These factors involve complex biological and physical variables distributed over time. Because such carcinogenic effects occur too infrequently to be demonstrated at low doses, the risks of low-dose radiation can be estimated only by interpolation from observations at high doses on the basis of theoretical concepts, mathematical models and available empirical evidence, primarily the epidemiological surveys of large populations exposed to ionizing radiation. In spite of a considerable amount of research, only recently has there has been efforts to apply the extensive laboratory data in animals to define the dose-incidence relationship in the low dose region. There simply are insufficient data in the epidemiological studies of large human populations to estimate risk coefficients directly from exposure to low doses. The risk estimates for the carcinogenic effects of radiation have been, in the past, somewhat low and reassessment of the numerical values is now necessary.

  15. The carcinogenic risks of low-LET and high-LET ionizing radiations

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I. (Lawrence Berkeley Lab., CA (United States) California Univ., San Francisco, CA (United States))

    1991-08-01

    This report presents a discussion on risk from ionizing radiations to human populations. Important new information on human beings has come mainly from further follow-up of existing epidemiological studies, notably the Japanese atomic bomb survivors and the ankylosing spondylitis patients; from new epidemiological surveys, such as the patients treated for cancer of the uterine cervix; and from combined surveys, including workers exposed in underground mines. Since the numerous and complex differences among the different study populations introduce factors that influence the risk estimates derived in ways that are not completely understood, it is not clear how to combine the different risk estimates obtained. These factors involve complex biological and physical variables distributed over time. Because such carcinogenic effects occur too infrequently to be demonstrated at low doses, the risks of low-dose radiation can be estimated only by interpolation from observations at high doses on the basis of theoretical concepts, mathematical models and available empirical evidence, primarily the epidemiological surveys of large populations exposed to ionizing radiation. In spite of a considerable amount of research, only recently has there has been efforts to apply the extensive laboratory data in animals to define the dose-incidence relationship in the low dose region. There simply are insufficient data in the epidemiological studies of large human populations to estimate risk coefficients directly from exposure to low doses. The risk estimates for the carcinogenic effects of radiation have been, in the past, somewhat low and reassessment of the numerical values is now necessary.

  16. SU-E-T-208: Incidence Cancer Risk From the Radiation Treatment for Acoustic Neuroma Patient

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D [Kyung Hee University International Med. Serv., Seoul (Korea, Republic of); Chung, W [Kyung Hee University Hospital at Gangdong, Seoul, Seoul (Korea, Republic of); Shin, D [Kyung Hee University Hospital, Seoul, Seoul (Korea, Republic of); Yoon, M [Korea University, Seoul (Korea, Republic of)

    2014-06-01

    Purpose: The present study aimed to compare the incidence risk of a secondary cancer from therapeutic doses in patients receiving intensitymodulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic radiosurgery (SRS). Methods: Four acoustic neuroma patients were treated with IMRT, VMAT, or SRS. Their incidnece excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) were estimated using the corresponding therapeutic doses measured at various organs by radio-photoluminescence glass dosimeters (RPLGD) placed inside a humanoid phantom. Results: When a prescription dose was delivered in the planning target volume of the 4 patients, the average organ equivalent doses (OED) at the thyroid, lung, normal liver, colon, bladder, prostate (or ovary), and rectum were measured. The OED decreased as the distance from the primary beam increased. The thyroid received the highest OED compared to other organs. A LAR were estimated that more than 0.03% of AN patients would get radiation-induced cancer. Conclusion: The tyroid was highest radiation-induced cancer risk after radiation treatment for AN. We found that LAR can be increased by the transmitted dose from the primary beam. No modality-specific difference in radiation-induced cancer risk was observed in our study.

  17. Balancing Type I Risk and Loss of Power in Ordered Bonferroni Procedures.

    Science.gov (United States)

    de Cani, John S.

    1984-01-01

    While Bonferroni procedures control the risk of Type I errors, their cost is loss of power. Ordered Bonferroni procedures conserve power for more important tests while sacrificing power for less important tests. Both costs and benefits should be considered when choosing weights for individual tests and the overall level of Type I error protection.…

  18. Balancing Cost and Risk: The Treatment of Renewable Energy in Western Utility Resource Plans

    Energy Technology Data Exchange (ETDEWEB)

    Bolinger, Mark; Wiser, Ryan

    2005-08-10

    Markets for renewable energy have historically been motivated primarily by policy efforts, but a less widely recognized driver is poised to also play a major role in the coming years: utility integrated resource planning (IRP). Resource planning has re-emerged in recent years as an important tool for utilities and regulators, particularly in regions where retail competition has failed to take root. In the western United States, the most recent resource plans contemplate a significant amount of renewable energy additions. These planned additions--primarily coming from wind power--are motivated by the improved economics of wind power, a growing acceptance of wind by electric utilities, and an increasing recognition of the inherent risks (e.g., natural gas price risk, environmental compliance risk) in fossil-based generation portfolios. This report examines how twelve western utilities treat renewable energy in their recent resource plans. In aggregate, these utilities supply approximately half of all electricity demand in the western United States. Our purpose is twofold: (1) to highlight the growing importance of utility IRP as a current and future driver of renewable energy, and (2) to identify methodological/modeling issues, and suggest possible improvements to methods used to evaluate renewable energy as a resource option. Here we summarize the key findings of the report, beginning with a discussion of the planned renewable energy additions called for by the twelve utilities, an overview of how these plans incorporated renewables into candidate portfolios, and a review of the specific technology cost and performance assumptions they made, primarily for wind power. We then turn to the utilities' analysis of natural gas price and environmental compliance risks, and examine how the utilities traded off portfolio cost and risk in selecting a preferred portfolio.

  19. Risk of Radiation Retinopathy in Patients With Orbital and Ocular Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Kaushik, Megha; Pulido, Jose S. [Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota (United States); Schild, Steven E. [Division of Radiation Oncology, Mayo Clinic, Scottsdale, Arizona (United States); Stafford, Scott, E-mail: stafford.scott@mayo.edu [Division of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2012-12-01

    Purpose: Radiation retinopathy is a potential long-term complication of radiation therapy to the orbit. The risk of developing this adverse effect is dose dependent; however, the threshold is unclear. The aim of this study was to identify the risk of developing radiation retinopathy at increasing radiation doses. Methods and Materials: A 40-year retrospective review was performed of patients who received external beam radiation therapy for ocular/orbital non-Hodgkin lymphoma (NHL). Results: Sixty-seven patients who had at least one ophthalmic follow-up examination were included in this study. Most patients (52%) were diagnosed with NHL involving the orbit. Patients received external beam radiation therapy at doses between 1886 and 5400 cGy (mean, 3033 {+-} 782 cGy). Radiation retinopathy developed in 12% of patients, and the median time to diagnosis was 27 months (range, 15-241months). The mean prescribed radiation dose in patients with retinopathy was 3309 {+-} 585 cGy, and the estimated retinal dose (derived by reviewing the dosimetry) was 3087 {+-} 1030 cGy. The incidence of retinopathy increased with dose. The average prescribed daily fractionated dose was higher in patients who developed retinopathy than in patients who did not (mean, 202 cGy vs 180 cGy, respectively; P = .04). More patients with radiation retinopathy had comorbid diabetes mellitus type 2 than patients without retinopathy (P = .015). In our study, the mean visual acuity of the eyes that received radiation was worse than that of the eyes that did not (P = .027). Other postradiotherapy ocular findings included keratitis (6%), dry eyes (39%), and cataract (33%). Conclusions: Radiation retinopathy, a known complication of radiotherapy for orbital tumors, relates to vascular comorbidities and dose. Higher total doses and larger daily fractions (>180 cGy) appear to be related to higher rates of retinopathy. Future larger studies are required to identify a statistically significant threshold for the

  20. Risk of Radiation Retinopathy in Patients With Orbital and Ocular Lymphoma

    International Nuclear Information System (INIS)

    Purpose: Radiation retinopathy is a potential long-term complication of radiation therapy to the orbit. The risk of developing this adverse effect is dose dependent; however, the threshold is unclear. The aim of this study was to identify the risk of developing radiation retinopathy at increasing radiation doses. Methods and Materials: A 40-year retrospective review was performed of patients who received external beam radiation therapy for ocular/orbital non-Hodgkin lymphoma (NHL). Results: Sixty-seven patients who had at least one ophthalmic follow-up examination were included in this study. Most patients (52%) were diagnosed with NHL involving the orbit. Patients received external beam radiation therapy at doses between 1886 and 5400 cGy (mean, 3033 ± 782 cGy). Radiation retinopathy developed in 12% of patients, and the median time to diagnosis was 27 months (range, 15-241months). The mean prescribed radiation dose in patients with retinopathy was 3309 ± 585 cGy, and the estimated retinal dose (derived by reviewing the dosimetry) was 3087 ± 1030 cGy. The incidence of retinopathy increased with dose. The average prescribed daily fractionated dose was higher in patients who developed retinopathy than in patients who did not (mean, 202 cGy vs 180 cGy, respectively; P = .04). More patients with radiation retinopathy had comorbid diabetes mellitus type 2 than patients without retinopathy (P = .015). In our study, the mean visual acuity of the eyes that received radiation was worse than that of the eyes that did not (P = .027). Other postradiotherapy ocular findings included keratitis (6%), dry eyes (39%), and cataract (33%). Conclusions: Radiation retinopathy, a known complication of radiotherapy for orbital tumors, relates to vascular comorbidities and dose. Higher total doses and larger daily fractions (>180 cGy) appear to be related to higher rates of retinopathy. Future larger studies are required to identify a statistically significant threshold for the

  1. Mars Radiation Risk Assessment and Shielding Design for Long-term Exposure to Ionizing Space Radiation

    Science.gov (United States)

    Tripathi, Ram K.; Nealy, John E.

    2007-01-01

    NASA is now focused on the agency's vision for space exploration encompassing a broad range of human and robotic missions including missions to Moon, Mars and beyond. As a result, there is a focus on long duration space missions. NASA is committed to the safety of the missions and the crew, and there is an overwhelming emphasis on the reliability issues for space missions and the habitat. The cost-effective design of the spacecraft demands a very stringent requirement on the optimization process. Exposure from the hazards of severe space radiation in deep space and/or long duration missions is a critical design constraint and a potential 'show stopper'. Thus, protection from the hazards of severe space radiation is of paramount importance to the agency's vision. It is envisioned to have long duration human presence on the Moon for deep space exploration. The exposures from ionizing radiation - galactic cosmic radiation and solar particle events - and optimized shield design for a swing-by and a long duration Mars mission have been investigated. It is found that the technology of today is inadequate for safe human missions to Mars, and revolutionary technologies need to be developed for long duration and/or deep space missions. The study will provide a guideline for radiation exposure and protection for long duration missions and career astronauts and their safety.

  2. A novel tool for user-friendly estimation of natural, diagnostic and professional radiation risk: Radio-Risk software

    Energy Technology Data Exchange (ETDEWEB)

    Carpeggiani, Clara; Paterni, Marco [CNR, Institute of Clinical Physiology (Italy); Caramella, Davide [Radiology Department, Pisa University, Pisa (Italy); Vano, Eliseo [San Carlos Hospital, Radiology Department, Complutense University, Madrid (Spain); Semelka, Richard C. [University of North Carolina, Chapel Hill, NC (United States); Picano, Eugenio, E-mail: picano@ifc.cnr.it [CNR, Institute of Clinical Physiology (Italy)

    2012-11-15

    Background: Awareness of radiological risk is low among doctors and patients. An educational/decision tool that considers each patient' s cumulative lifetime radiation exposure would facilitate provider-patient communication. Aim: The purpose of this work was to develop user-friendly software for simple estimation and communication of radiological risk to patients and doctors as a part of the SUIT-Heart (Stop Useless Imaging Testing in Heart disease) Project of the Tuscany Region. Methods: We developed a novel software program (PC-platform, Windows OS fully downloadable at (http://suit-heart.ifc.cnr.it)) considering reference dose estimates from American Heart Association Radiological Imaging 2009 guidelines and UK Royal College of Radiology 2007 guidelines. Cancer age and gender-weighted risk were derived from Biological Effects of Ionising Radiation VII Committee, 2006. Results: With simple input functions (demographics, age, gender) the user selects from a predetermined menu variables relating to natural (e.g., airplane flights and geo-tracked background exposure), professional (e.g., cath lab workers) and medical (e.g., CT, cardiac scintigraphy, coronary stenting) sources. The program provides a simple numeric (cumulative effective dose in milliSievert, mSv, and equivalent number of chest X-rays) and graphic (cumulative temporal trends of exposure, cancer cases out of 100 exposed persons) display. Conclusions: A simple software program allows straightforward estimation of cumulative dose (in multiples of chest X-rays) and risk (in extra % lifetime cancer risk), with simple numbers quantifying lifetime extra cancer risk. Pictorial display of radiation risk may be valuable for increasing radiological awareness in cardiologists.

  3. Does ionizing radiation influence Alzheimer's disease risk?

    International Nuclear Information System (INIS)

    Alzheimer's disease (AD) is a human neurodegenerative disease, and its global prevalence is predicted to increase dramatically in the following decades. There is mounting evidence describing the effects of ionizing radiation (IR) on the brain, suggesting that exposure to IR might ultimately favor the development of AD. Therefore better understanding the possible connections between exposure to IR and AD pathogenesis is of utmost importance. In this review, recent developments in the research on the biological and cognitive effects of IR in the brain will be explored. Because AD is largely an age-related pathology, the effects of IR on ageing will be investigated

  4. Two- and Three-Dimensional Models for Risk Assessment of Radiation-Enhanced Colorectal Tumorigenesis

    OpenAIRE

    Roig, Andres I.; Hight, Suzie K.; Jerry W Shay

    2009-01-01

    Astronauts may be at an increased risk for developing colorectal cancer after a prolonged interplanetary mission given the potential for greater carcinogenic effects of radiation to the colon. In addition, with an increase in age, there is a greater incidence of premalignant colon adenomas with age. In the present study, we have compared the effects of radiation on human colon epithelial cells in two-dimensional (2D) monolayer culture, in three-dimensional (3D) culture, and in intact human co...

  5. Cancer risk at low doses of ionizing radiation: artificial neural networks inference from atomic bomb survivors

    OpenAIRE

    Sasaki, Masao S.; Tachibana, Akira; Takeda, Shunichi

    2013-01-01

    Cancer risk at low doses of ionizing radiation remains poorly defined because of ambiguity in the quantitative link to doses below 0.2 Sv in atomic bomb survivors in Hiroshima and Nagasaki arising from limitations in the statistical power and information available on overall radiation dose. To deal with these difficulties, a novel nonparametric statistics based on the ‘integrate-and-fire’ algorithm of artificial neural networks was developed and tested in cancer databases established by the R...

  6. Cancer risk at low doses of ionizing radiation: artificial neural networks inference from atomic bomb survivors.

    OpenAIRE

    Sasaki, Masao S.; Tachibana, Akira; Takeda, Shunichi

    2014-01-01

    Cancer risk at low doses of ionizing radiation remains poorly defined because of ambiguity in the quantitative link to doses below 0.2 Sv in atomic bomb survivors in Hiroshima and Nagasaki arising from limitations in the statistical power and information available on overall radiation dose. To deal with these difficulties, a novel nonparametric statistics based on the 'integrate-and-fire' algorithm of artificial neural networks was developed and tested in cancer databases established by the R...

  7. Genetic radiation risks: a neglected topic in the low dose debate

    OpenAIRE

    Schmitz-Feuerhake, Inge; Busby, Christopher; Pflugbeil, Sebastian

    2016-01-01

    Objectives To investigate the accuracy and scientific validity of the current very low risk factor for hereditary diseases in humans following exposures to ionizing radiation adopted by the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Commission on Radiological Protection. The value is based on experiments on mice due to reportedly absent effects in the Japanese atomic bomb (Abomb) survivors. Methods To review the published evidence for heritabl...

  8. Prevention of risks in relation with occupational exposure to ionizing radiation

    International Nuclear Information System (INIS)

    After remind the base notions in the field of ionizing radiation, this file evaluates the situation on the natural and occupational exposures: modes, sources, and exposure level, risk for health. It presents the principles of prevention allowing in a professional area (out of nuclear industry) to reduce and control these exposures. Some practical cases illustrate the radiation protection approach. references are given: regulatory benchmarks, useful links, books to consult. (N.C.)

  9. Communication as a tool to modify the negative perception of radiation risk

    International Nuclear Information System (INIS)

    The radiation risks are probably for historical reasons related to their military origin, the paradigm of subjectivity and its perception by the population has become increasingly of interest to those responsible for management and management of any applications of ionizing radiation. This interest is positive because the more you know, the better will the conditions to try to change attitudes and approaches to the problem, particularly from the point of view of communication with society.

  10. Mobile phone radiation health risk controversy: the reliability and sufficiency of science behind the safety standards

    OpenAIRE

    Leszczynski Dariusz; Xu Zhengping

    2010-01-01

    Abstract There is ongoing discussion whether the mobile phone radiation causes any health effects. The International Commission on Non-Ionizing Radiation Protection, the International Committee on Electromagnetic Safety and the World Health Organization are assuring that there is no proven health risk and that the present safety limits protect all mobile phone users. However, based on the available scientific evidence, the situation is not as clear. The majority of the evidence comes from in ...

  11. Risk of second bone sarcoma following childhood cancer: role of radiation therapy treatment.

    Science.gov (United States)

    Schwartz, Boris; Benadjaoud, Mohamed Amine; Cléro, Enora; Haddy, Nadia; El-Fayech, Chiraz; Guibout, Catherine; Teinturier, Cécile; Oberlin, Odile; Veres, Cristina; Pacquement, Hélène; Munzer, Martine; N'guyen, Tan Dat; Bondiau, Pierre-Yves; Berchery, Delphine; Laprie, Anne; Hawkins, Mike; Winter, David; Lefkopoulos, Dimitri; Chavaudra, Jean; Rubino, Carole; Diallo, Ibrahima; Bénichou, Jacques; de Vathaire, Florent

    2014-05-01

    Bone sarcoma as a second malignancy is rare but highly fatal. The present knowledge about radiation-absorbed organ dose-response is insufficient to predict the risks induced by radiation therapy techniques. The objective of the present study was to assess the treatment-induced risk for bone sarcoma following a childhood cancer and particularly the related risk of radiotherapy. Therefore, a retrospective cohort of 4,171 survivors of a solid childhood cancer treated between 1942 and 1986 in France and Britain has been followed prospectively. We collected detailed information on treatments received during childhood cancer. Additionally, an innovative methodology has been developed to evaluate the dose-response relationship between bone sarcoma and radiation dose throughout this cohort. The median follow-up was 26 years, and 39 patients had developed bone sarcoma. It was found that the overall incidence was 45-fold higher [standardized incidence ratio 44.8, 95 % confidence interval (CI) 31.0-59.8] than expected from the general population, and the absolute excess risk was 35.1 per 100,000 person-years (95 % CI 24.0-47.1). The risk of bone sarcoma increased slowly up to a cumulative radiation organ absorbed dose of 15 Gy [hazard ratio (HR) = 8.2, 95 % CI 1.6-42.9] and then strongly increased for higher radiation doses (HR for 30 Gy or more 117.9, 95 % CI 36.5-380.6), compared with patients not treated with radiotherapy. A linear model with an excess relative risk per Gy of 1.77 (95 % CI 0.6213-5.935) provided a close fit to the data. These findings have important therapeutic implications: Lowering the radiation dose to the bones should reduce the incidence of secondary bone sarcomas. Other therapeutic solutions should be preferred to radiotherapy in bone sarcoma-sensitive areas.

  12. Mobile phone radiation health risk controversy: the reliability and sufficiency of science behind the safety standards

    Directory of Open Access Journals (Sweden)

    Leszczynski Dariusz

    2010-01-01

    Full Text Available Abstract There is ongoing discussion whether the mobile phone radiation causes any health effects. The International Commission on Non-Ionizing Radiation Protection, the International Committee on Electromagnetic Safety and the World Health Organization are assuring that there is no proven health risk and that the present safety limits protect all mobile phone users. However, based on the available scientific evidence, the situation is not as clear. The majority of the evidence comes from in vitro laboratory studies and is of very limited use for determining health risk. Animal toxicology studies are inadequate because it is not possible to "overdose" microwave radiation, as it is done with chemical agents, due to simultaneous induction of heating side-effects. There is a lack of human volunteer studies that would, in unbiased way, demonstrate whether human body responds at all to mobile phone radiation. Finally, the epidemiological evidence is insufficient due to, among others, selection and misclassification bias and the low sensitivity of this approach in detection of health risk within the population. This indicates that the presently available scientific evidence is insufficient to prove reliability of the current safety standards. Therefore, we recommend to use precaution when dealing with mobile phones and, whenever possible and feasible, to limit body exposure to this radiation. Continuation of the research on mobile phone radiation effects is needed in order to improve the basis and the reliability of the safety standards.

  13. Getting ready for the manned mission to Mars: the astronauts' risk from space radiation.

    Science.gov (United States)

    Hellweg, Christine E; Baumstark-Khan, Christa

    2007-07-01

    Space programmes are shifting towards planetary exploration and, in particular, towards missions by human beings to the Moon and to Mars. Radiation is considered to be one of the major hazards for personnel in space and has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. The two cosmic sources of radiation that could impact a mission outside the Earth's magnetic field are solar particle events (SPE) and galactic cosmic rays (GCR). Exposure to the types of ionizing radiation encountered during space travel may cause a number of health-related problems, but the primary concern is related to the increased risk of cancer induction in astronauts. Predictions of cancer risk and acceptable radiation exposure in space are extrapolated from minimal data and are subject to many uncertainties. The paper describes present-day estimates of equivalent doses from GCR and solar cosmic radiation behind various shields and radiation risks for astronauts on a mission to Mars.

  14. Getting ready for the manned mission to Mars: the astronauts' risk from space radiation.

    Science.gov (United States)

    Hellweg, Christine E; Baumstark-Khan, Christa

    2007-07-01

    Space programmes are shifting towards planetary exploration and, in particular, towards missions by human beings to the Moon and to Mars. Radiation is considered to be one of the major hazards for personnel in space and has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. The two cosmic sources of radiation that could impact a mission outside the Earth's magnetic field are solar particle events (SPE) and galactic cosmic rays (GCR). Exposure to the types of ionizing radiation encountered during space travel may cause a number of health-related problems, but the primary concern is related to the increased risk of cancer induction in astronauts. Predictions of cancer risk and acceptable radiation exposure in space are extrapolated from minimal data and are subject to many uncertainties. The paper describes present-day estimates of equivalent doses from GCR and solar cosmic radiation behind various shields and radiation risks for astronauts on a mission to Mars. PMID:17235598

  15. NCRP Program Area Committee 7: Radiation Education, Risk Communication, Outreach, and Policy.

    Science.gov (United States)

    Becker, S M; Locke, P A

    2016-02-01

    Recognizing the central importance of effective communication, education, and policy across all of the domains of radiation safety and radiation protection, the National Council on Radiation Protection and Measurements (NCRP) established a new committee in 2013. Program Area Committee 7 (PAC 7) was created to develop projects and provide guidance on "Radiation Education, Risk Communication, Outreach, and Policy." After identifying individuals with relevant expertise who were willing to serve, the Committee held its inaugural meeting in 2014. In 2015, the Committee increased its membership and began carrying out an expanded program of activities. One area of activity has involved providing input and feedback on risk communication issues to NCRP and other agencies. Another area of work has involved liaising with other NCRP committees (e.g., Council Committee 1 and PAC 3) to help incorporate psychosocial and risk communication issues into projects. Future efforts of NCRP's newest PAC are expected to include the development of authoritative reports and commentaries dealing with critical issues and challenges in radiation risk communication, education, and policy.

  16. Evaluation of risk from space radiation with high-energy heavy ion beams

    Science.gov (United States)

    Schimmerling, W.; Wilson, J. W.; Cucinotta, F.; Kim, M. H.

    1998-01-01

    The most challenging radiation in space consists of fully ionized atomic elements with high energy for which only the few lowest energy ions can be stopped in shielding materials. The health risk from exposure to these ions and their secondary radiations generated in shield materials is poorly understood since there are few human data and a systematic study in relevant animal model systems has not been made. The accuracy of risk prediction is described as the major limiting factor in the management of space radiation risk. The expected impact of systematic studies is examined using the limited available biological data and models. Given the limitations of current predictions, models must be developed that are able to incorporate the required fundamental scientific data into accurate risk estimates. The important radiation components that can be provided for laboratory testing are identified. The use of ground-based accelerator beams to simulate space radiation is explained and quantitative scientific constraints on such facilities are derived. Three facilities, one each in the United States, in Germany and in Japan, currently have the partial capability to satisfy these constraints. A facility has been proposed using the Brookhaven National Laboratory Booster Synchrotron in the United States; in conjuction with other on-site accelerators, it will be able to provide the full range of heavy ion beams and energies required.

  17. NCRP Program Area Committee 7: Radiation Education, Risk Communication, Outreach, and Policy.

    Science.gov (United States)

    Becker, S M; Locke, P A

    2016-02-01

    Recognizing the central importance of effective communication, education, and policy across all of the domains of radiation safety and radiation protection, the National Council on Radiation Protection and Measurements (NCRP) established a new committee in 2013. Program Area Committee 7 (PAC 7) was created to develop projects and provide guidance on "Radiation Education, Risk Communication, Outreach, and Policy." After identifying individuals with relevant expertise who were willing to serve, the Committee held its inaugural meeting in 2014. In 2015, the Committee increased its membership and began carrying out an expanded program of activities. One area of activity has involved providing input and feedback on risk communication issues to NCRP and other agencies. Another area of work has involved liaising with other NCRP committees (e.g., Council Committee 1 and PAC 3) to help incorporate psychosocial and risk communication issues into projects. Future efforts of NCRP's newest PAC are expected to include the development of authoritative reports and commentaries dealing with critical issues and challenges in radiation risk communication, education, and policy. PMID:26717162

  18. Appraisal of individual radiation risk in the context of probabilistic exposures

    International Nuclear Information System (INIS)

    There exists a growing desire to base safety criteria in different fields on the same principles. The current approach by the international Commission on Radiological Protection (ICRP) to control radiation exposure touches many aspects such as social, psychological, or economic factors that are important for such principles. This paper attempts to further explore possible ways of defining a common basis for dealing with radiation risks and other safety problems. Specifically, it introduces the following issues: different types of risk are judged differently. To account for this, the concept of risk categories is introduced. The dimension of time may play an important role. There is a difference between an immediate death and a death occurring 20 years after exposure to radiation. Effects such as reduced quality of life after exposure and reduction of lifetime expectancy are discussed. The paper suggests to introduce an individual risk equivalent which allows to compare risks as defined in various fields. Furthermore, it suggests the use of risk acceptance criteria which depend on the different categories of risk

  19. Cancer risk among atomic bomb survivors. The RERF Life Span Study. Radiation Effects Research Foundation.

    Science.gov (United States)

    Shimizu, Y; Schull, W J; Kato, H

    1990-08-01

    This article summarizes the risk of cancer among the survivors of the atomic bombing of Hiroshima and Nagasaki. We focus primarily on the risk of death from cancer among individuals in the Life Span Study sample of the Radiation Effects Research Foundation from 1950 through 1985 based on recently revised dosimetry procedures. We report the risk of cancer other than leukemia among the atomic bomb survivors. We note that the number of excess deaths of radiation-induced malignant tumors other than leukemia increases with age. Survivors who were exposed in the first or second decade of life have just entered the cancer-prone age and have so far exhibited a high relative risk in association with radiation dose. Whether the elevated risk will continue or will fall with time is not yet clear, although some evidence suggests that the risk may be declining. It is important to continue long-term follow-up of this cohort to document the changes with time since exposure and to provide direct rather than projected risks over the lifetime of an exposed individual. PMID:2366300

  20. Cancer and non-cancer risk at low doses of radiation: biological basis of radiation-environment interplay

    International Nuclear Information System (INIS)

    Cancer and non-cancer risk at low doses of ionizing radiation remains poorly defined due to ambiguity at low doses caused by limitations in statistical power and information available on interplay with environment. To deal with these problems, a novel non-parametric statistics was developed based on artificial neural networks theorem and applied to cancer and non-cancer risk in A-bomb survivors. The analysis revealed several unique features at low doses that could not be accounted for by nominal radiation dose alone. They include (1) threshold that varies with organ, gender and age, including cardiovascular diseases, (2) prevalence of infectious diseases, and (3) suppression of pathogenesis of HTLV1. The threshold is unique as it is manifested as negative excess relative risk, a reduction of spontaneous rate at low doses. The response is consistent with currently emerging laboratory data on DNA double-strand break (DSB) repair pathway choice and its sustainability as epigenetic memory in accordance with histone code theory. In response to DSB, of radiation or DNA replication arrest origin, distinct and competitively operating repair pathways are instigated. Activation by low doses of restitution-directed canonical non-homologous end-joining (C-NHEJ) suppresses both error-prone alternative end-joining (Alt-NHEJ) and homologous recombination (HR). The latter two present major pathways to mutagenesis at stalled replication folk associated with endogenous and exogenous genotoxin such as tobacco smoke metabolites and AID-associated somatic hypermutation and class switch recombination in Ig gene. Suppression of these error-prone pathways by low doses of low LET radiation is consistent with the reduction of cancer occurrence by environmental genotoxin, immunodiversity and stable integration of retrovirus DNA, providing a significant modulator of dose linearity at low doses. Whole picture may bring about a new landscape of cancer and non-cancer molecular epidemiology which

  1. Ultraviolet radiation emitted by lamps, TVs, tablets and computers: are there risks for the population?

    Science.gov (United States)

    Duarte, Ida Alzira Gomes; Hafner, Mariana de Figueiredo Silva; Malvestiti, Andrey Augusto

    2015-01-01

    The frequent human exposure to various types of indoor lamps, as well as other light sources (television monitors, tablets and computers), raises a question: are there risks for the population? In the present study the emission of UVA and UVB radiation by lamps and screens of electronic devices were measured in order to determine the safe distance between the emitting source and the individual. We concluded that the lamps and electronic devices do not emit ultraviolet radiation; so they pose no health risk for the population.

  2. Theoretical epidemiology applied to health physics: estimation of the risk of radiation-induced breast cancer

    International Nuclear Information System (INIS)

    Indirect estimation of low-dose radiation hazards is possible using the multihit model of carcinogenesis. This model is based on cancer incidence data collected over many decades on tens of millions of people. Available data on human radiation effects can be introduced into the modeling process without the requirement that these data precisely define the model to be used. This reduction in the information demanded from the limited data on human radiation effects allows a more rational approach to estimation of low-dose radiation hazards and helps to focus attention on research directed towards understanding the process of carcinogenesis, rather than on repeating human or animal experiments that cannot provide sufficient data to resolve the low-dose estimation problem. Assessment of the risk of radiation-induced breast cancer provides an excellent example of the utility of multihit modeling procedures

  3. PROBLEMS OF PERCEPTION AND SUBJECTIVE ASSESSMENT OF RISK FROM IONIZING RADIATION

    Directory of Open Access Journals (Sweden)

    G. M. Rumyantseva

    2009-01-01

    Full Text Available Perception of risk from ionizing radiation is the basis ofpsychic traumatizing during radiological accidents and incidents. Various approaches to the evaluation of this phenomenon and the results ofresearch done during the last twenty years are analyzed in the article. It is shown that cognitive representations ofrisk, emotional value attitude to the radiation hazard, motivation andpersonal attitudes, strategies and social and psychological resources of radiation threat processing and overcoming are presented and are in the complex interaction at the same time in this multi-component composition.

  4. Radiation risk and nuclear medicine: An interview with a Nobel Prize winner

    Energy Technology Data Exchange (ETDEWEB)

    Yalow, R.S.

    1995-12-01

    In a speech given years ago at the Veterans Administration Medical Center, Bronx, NY, Rosalyn S. Yalow, 1977 Nobel Prize recipient for her invention of radioimmunoassay, made several salient points on the perception of fear or hazards from exposure to low-level radiation and low-level radioactive wastes. For the past three years, Yalow has been concerned with the general fear of radiation. In this interview, Newsline solicited Yalow`s views on public perceptions on radiation risk and what the nuclear medicine community can do to emphasize the fact that, if properly managed, the use of isotopes in medicine and other cases is not dangerous.

  5. Radiation risk and nuclear medicine: An interview with a Nobel Prize winner

    International Nuclear Information System (INIS)

    In a speech given years ago at the Veterans Administration Medical Center, Bronx, NY, Rosalyn S. Yalow, 1977 Nobel Prize recipient for her invention of radioimmunoassay, made several salient points on the perception of fear or hazards from exposure to low-level radiation and low-level radioactive wastes. For the past three years, Yalow has been concerned with the general fear of radiation. In this interview, Newsline solicited Yalow's views on public perceptions on radiation risk and what the nuclear medicine community can do to emphasize the fact that, if properly managed, the use of isotopes in medicine and other cases is not dangerous

  6. Response to Out of Balance: The risk of irreversible climate change

    International Nuclear Information System (INIS)

    The Standing Committee on Environment of the Canadian House of Commons tabled a report entitled Out of Balance, which was an investigation of issues related to the increasing concentrations of greenhouse gases in the atmosphere and possible responses to impending climatic change. The government's response to the recommendations made in that report are presented. The framework to the government's response is first introduced, which includes the National Action Strategy on Global Warming (NASGW) that provides a strategy for Canadian initiatives to reduce greenhouse gas emissions. The strategy is based on the fundamental principles of comprehensiveness, the importance of international agreements, and flexibility. The Standing Committee's recommendations focused on policies to limit Canadian emissions of carbon dioxide, one of the major greenhouse gases. Canadian policies to achieve this goal are being implemented in the Green Plan and the NASGW. Other recommendations and responses involve environmental education, greenhouse gas data collection, phasing out of chlorofluorocarbons, natural gas leakage, energy conservation and demand management, regulatory systems, fuel efficiency standards, forest management, greenhouse gas emissions from federal departments and agencies, and encouragement of environmentally acceptable technologies

  7. Risk of a second cancer from scattered radiation in acoustic neuroma treatment

    Science.gov (United States)

    Yoon, Myonggeun; Lee, Hyunho; Sung, Jiwon; Shin, Dongoh; Park, Sungho; Chung, Weon Kuu; Jahng, Geon-Ho; Kim, Dong Wook

    2014-06-01

    The present study aimed to compare the risk of a secondary cancer from scattered and leakage doses in patients receiving intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic radiosurgery (SRS). Four acoustic neuroma patients were treated with IMRT, VMAT, or SRS. Their excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) of a secondary cancer were estimated using the corresponding secondary doses measured at various organs by using radio-photoluminescence glass dosimeters (RPLGD) placed inside a humanoid phantom. When a prescription dose was delivered in the planning target volume of the 4 patients, the average organ equivalent doses (OED) at the thyroid, lung, liver, bowel, bladder, prostate (or ovary), and rectum were 14.6, 1.7, 0.9, 0.8, 0.6, 0.6, and 0.6 cGy, respectively, for IMRT whereas they were 19.1, 1.8, 2.0, 0.6, 0.4, 0.4, and 0.4 cGy, respectively, for VMAT, and 22.8, 4.6, 1.4, 0.7, 0.5, 0.5, and 0.5 cGy, respectively, for SRS. The OED decreased as the distance from the primary beam increased. The thyroid received the highest OED compared to other organs. A lifetime attributable risk evaluation estimated that more than 0.03% of acoustic neuroma (AN) patients would get radiation-induced cancer within 20 years of receiving radiation therapy. The organ with the highest radiation-induced cancer risk after radiation treatment for AN was the thyroid. We found that the LAR could be increased by the transmitted dose from the primary beam. No modality-specific difference in radiation-induced cancer risk was observed in our study.

  8. Risk of a second cancer from scattered radiation in acoustic neuroma treatment

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Myonggeun; Lee, Hyunho; Sung, Jiwon [Korea University, Seoul (Korea, Republic of); Shin, Dongoh [Kyung Hee University Medical Center, Seoul (Korea, Republic of); Park, Sungho [Ulsan University Hospital, Ulsan (Korea, Republic of); Chung, Weonkuu; Jahng, Geonho; Kim, Dongwook [Kyung Hee University Hospital at Gangdong, Seoul (Korea, Republic of)

    2014-06-15

    The present study aimed to compare the risk of a secondary cancer from scattered and leakage doses in patients receiving intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), and stereotactic radiosurgery (SRS). Four acoustic neuroma patients were treated with IMRT, VMAT, or SRS. Their excess relative risk (ERR), excess absolute risk (EAR), and lifetime attributable risk (LAR) of a secondary cancer were estimated using the corresponding secondary doses measured at various organs by using radio-photoluminescence glass dosimeters (RPLGD) placed inside a humanoid phantom. When a prescription dose was delivered in the planning target volume of the 4 patients, the average organ equivalent doses (OED) at the thyroid, lung, liver, bowel, bladder, prostate (or ovary), and rectum were 14.6, 1.7, 0.9, 0.8, 0.6, 0.6, and 0.6 cGy, respectively, for IMRT whereas they were 19.1, 1.8, 2.0, 0.6, 0.4, 0.4, and 0.4 cGy, respectively, for VMAT, and 22.8, 4.6, 1.4, 0.7, 0.5, 0.5, and 0.5 cGy, respectively, for SRS. The OED decreased as the distance from the primary beam increased. The thyroid received the highest OED compared to other organs. A lifetime attributable risk evaluation estimated that more than 0.03% of acoustic neuroma (AN) patients would get radiation-induced cancer within 20 years of receiving radiation therapy. The organ with the highest radiation-induced cancer risk after radiation treatment for AN was the thyroid. We found that the LAR could be increased by the transmitted dose from the primary beam. No modality-specific difference in radiation-induced cancer risk was observed in our study.

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

    Science.gov (United States)

    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.

  10. Fluid and electrolyte balance during the first week of life and risk of bronchopulmonary dysplasia in the preterm neonate

    Directory of Open Access Journals (Sweden)

    Gustavo Rocha

    2010-01-01

    Full Text Available BACKGROUND: Early fluid and electrolyte imbalances may be associated with an increased risk of bronchopulmonary dysplasia. OBJECTIVE: We sought to establish an association between fluid and electrolyte balance in the first week of life and the risk of bronchopulmonary dysplasia. METHODS: Clinical charts of 205 neonates <32 weeks gestational age and/or <1,250 g birth weight (admitted to our NICU between 1997 and 2008 were analyzed. Clinical features, fluid and electrolyte balance were analyzed for the first 7 days of life using multivariate models of generalized estimation equations. A p value <0.05 was considered significant in all of the hypothesis tests. RESULTS: The prevalence of bronchopulmonary dysplasia was 22%. Lower gestational age and birth weight, male gender, less frequent use of antenatal steroids, respiratory distress syndrome, use of surfactant, patent ductus arteriosus, duration of invasive ventilation and NICU stay were significantly associated with bronchopulmonary dysplasia. The variation in serum values of potassium, phosphorus and creatinine during the first week of life also revealed an association with bronchopulmonary dysplasia. Higher mean plasma calcium values were associated with spontaneous closure of the patent ductus arteriosus. The use of indomethacin to induce patent ductus arteriosus closure was significantly higher in bronchopulmonary dysplasia patients. CONCLUSIONS: Differences in renal function and tubular handling of potassium and phosphorus are present during the first week of life among preterm neonates who will develop bronchopulmonary dysplasia. The higher rate of patent ductus arteriosus and indomethacin use may influence these differences. Serum levels of calcium also appear to play a role in spontaneous ductus arteriosus closure.

  11. Public Health Concern on Fukushima Radiation Risks in Korea and Response Strategies

    International Nuclear Information System (INIS)

    This paper reviews the characteristics of public perception on radiation risks by Fukushima Daiichi nuclear power plant accident and aims to suggest the appropriate strategies for minimizing social anxiety and managing the risk effectively on the basis of those features. In South Korea, the nearest country to Japan, fishery sales decreased 20% in 2013 due to consumers' fears over radiation contaminated seafood products. Public health concern is also increasing. The characteristics of public perception on the risk are the key factors of social anxiety, which are 'ongoing hazard' and 'uncertainty'. They can be translated same as the concepts of 'fear' and 'unknown risk', the psychometric factors of risk perception described in Slovic (1989)'s qualitative characteristics. News on a series of hazardous situations such as radioactive water leaks or radioactive steam at Fukushima is continually reported. Noting no expectation of accident settlement in near future, media coverage which has the expression of 'the maximum permissible level of radiation' without any translation of the measured dosimetric quantity causes the public's phobic fear. Uncertainties on health risks of low dose ionizing radiation in humans are not only the causes of fear but the challenges in building trust in risk communications. Rumours appear under ambiguous and uncertain situation with a lack of information. The communications among public authorities, related institutes, experts and the public become very important since the public health concern on radiation contamination turns into attention to the system of inspection, distribution, and regulation of imported food. The public shows deep interest in the safety standard of guidelines used in regulatory policy and safety management, which leads to a desire for participation in policy making process. Situational crisis communication theory can be applied to the situation quoted and offers a guidance on effective strategies. This study suggests

  12. Public Health Concern on Fukushima Radiation Risks in Korea and Response Strategies

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chaewon [Korea Institute of Radiological and Medical Sciences, 75 Nowon-Ro, Seoul 139-781 (Korea, Republic of)

    2014-07-01

    This paper reviews the characteristics of public perception on radiation risks by Fukushima Daiichi nuclear power plant accident and aims to suggest the appropriate strategies for minimizing social anxiety and managing the risk effectively on the basis of those features. In South Korea, the nearest country to Japan, fishery sales decreased 20% in 2013 due to consumers' fears over radiation contaminated seafood products. Public health concern is also increasing. The characteristics of public perception on the risk are the key factors of social anxiety, which are 'ongoing hazard' and 'uncertainty'. They can be translated same as the concepts of 'fear' and 'unknown risk', the psychometric factors of risk perception described in Slovic (1989)'s qualitative characteristics. News on a series of hazardous situations such as radioactive water leaks or radioactive steam at Fukushima is continually reported. Noting no expectation of accident settlement in near future, media coverage which has the expression of 'the maximum permissible level of radiation' without any translation of the measured dosimetric quantity causes the public's phobic fear. Uncertainties on health risks of low dose ionizing radiation in humans are not only the causes of fear but the challenges in building trust in risk communications. Rumours appear under ambiguous and uncertain situation with a lack of information. The communications among public authorities, related institutes, experts and the public become very important since the public health concern on radiation contamination turns into attention to the system of inspection, distribution, and regulation of imported food. The public shows deep interest in the safety standard of guidelines used in regulatory policy and safety management, which leads to a desire for participation in policy making process. Situational crisis communication theory can be applied to the situation quoted and

  13. Improvement of quantification of somatic radiation risks at low doses

    International Nuclear Information System (INIS)

    In this research contract several selected topics of basic relevancy for assessment models of radiological consequences of hypothetical reactor accidents have been considered. The investigations focussed on the following areas: 1) Age dependent dose conversion factors for members of the public and their variability for radioisotopes of iodine, strontium, and caesium, - improvement of the accuracy of dose calculations for external gamma irradiation from cloud- and ground-shine; 2) analysis of data and models relevant for the assessment of exposure-time-effect relationships for lethal somatic late effects of lung and breast cancer and of leukemia; 3) analysis of various health status indices (e.g. ''loss of healthy life span'') with respect to their usefulness in addition to incidence, mortality, etc. for the evaluation of the magnitude of a health detriment due to a previous radiation exposure. (orig./HP)

  14. Assessment of risks from occupational exposure to ionizing radiation

    International Nuclear Information System (INIS)

    The assessment of health effects from occupational exposure to radiation presents a variety of problems resulting from the time dependent nature of the exposure data, the more favorable health frequently experienced by working populations, and limits imposed by the size of the populations and the magnitudes of the exposures received. A proportional hazards model is used to derive tests for determining if statistically significant effects are present and is also considered for point estimation. Because effects of the size expected from current estimates are unlikely to be detected in occupationally exposed groups, methods of calculating upper confidence limits are considered. Data from the Hanford plant are used to illustrate many of the problems and procedures

  15. Contribution to the study of ionizing radiation ecological risks

    International Nuclear Information System (INIS)

    The amount of artificial irradiation delivered to man and the contribution due to medical applications are determined. The running of nuclear power stations is then analyzed, with special reference to problems concerning the reliability of different types of reactor, and an attempt made to implicate the irradiation attributed to nuclear industry as a whole and the effects produced on the environment. Lastly the effects of these ionizing radiations at low doses is examined. In the artificial radioactivity to which man is subjected (122 millirems a year) the contribution of X-rays is 103 millirems a year as against 3 millirems a year for nuclear industry, though it should be remembered that the majority of medical irradiation is the lot of a minority. According to the C.R.E.D.O.C., 75% of the radiological consumption is due to 20% of the population. These values lie below the M.A.D. values determined by the I.C.R.P. Irradiation from nuclear industry is still slight, but some reserves are expressed. No account is taken of the increasing build-up of certain very long-lived radioelements (plutonium 25000 years). Measurements provided on the contamination of the environment are inaccurate. Imprecision of the measurement methods and lack of knowledge of the concentration factor lead to neglect of this type of internal contamination through the food chain in spite of its apparent importance. For low-dose effects the arguments put forward are contradictory, optimistic on one side and pessimistic on the other. The proofs supplied by aggressive opponents of the improper use of ionizing radiations are disturbing: carcinogenesis, genetic damage etc.

  16. Information bias and lifetime mortality risks of radiation-induced cancer: Low LET radiation

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, L.E.; Schull, W.J.; Davis, B.R. [Texas Univ., Houston, TX (United States). Health Science Center; Buffler, P.A. [California Univ., Berkeley, CA (United States). School of Public Health

    1994-04-01

    Additive and multiplicative models of relative risk were used to measure the effect of cancer misclassification and DS86 random errors on lifetime risk projections in the Life Span Study (LSS) of Hiroshima and Nagasaki atomic bomb survivors. The true number of cancer deaths in each stratum of the cancer mortality cross-classification was estimated using sufficient statistics from the EM algorithm. Average survivor doses in the strata were corrected for DS86 random error ({sigma}=0.45) by use of reduction factors. Poisson regression was used to model the corrected and uncorrected mortality rates with risks in RERF Report 11 (Part 2) and the BEIR-V Report. Bias due to DS86 random error typically ranged from {minus}15% to {minus}30% for both sexes, and all sites and models. The total bias, including diagnostic misclassification, of excess risk of nonleukemia for exposure to 1 Sv from age 18 to 65 under the non-constant relative project model was {minus}37.1% for males and {minus}23.3% for females. Total excess risks of leukemia under the relative projection model were biased {minus}27.1% for males and {minus}43.4% for females. Thus, nonleukemia risks for 1 Sv from ages 18 to 65 (DRREF=2) increased from 1.91%/Sv to 2.68%/Sv among males and from 3.23%/Sv to 4.92%/Sv among females. Leukemia excess risk increased from 0.87%/Sv to 1.10/Sv among males and from 0.73%/Sv to 1.04/Sv among females. Bias was dependent on the gender, site, correction method, exposure profile and projection model considered. Future studies that use LSS data for US nuclear workers may be downwardly biased if lifetime risk projections are not adjusted for random and systematic errors.

  17. Information bias and lifetime mortality risks of radiation-induced cancer: Low LET radiation

    International Nuclear Information System (INIS)

    Additive and multiplicative models of relative risk were used to measure the effect of cancer misclassification and DS86 random errors on lifetime risk projections in the Life Span Study (LSS) of Hiroshima and Nagasaki atomic bomb survivors. The true number of cancer deaths in each stratum of the cancer mortality cross-classification was estimated using sufficient statistics from the EM algorithm. Average survivor doses in the strata were corrected for DS86 random error (σ=0.45) by use of reduction factors. Poisson regression was used to model the corrected and uncorrected mortality rates with risks in RERF Report 11 (Part 2) and the BEIR-V Report. Bias due to DS86 random error typically ranged from -15% to -30% for both sexes, and all sites and models. The total bias, including diagnostic misclassification, of excess risk of nonleukemia for exposure to 1 Sv from age 18 to 65 under the non-constant relative project model was -37.1% for males and -23.3% for females. Total excess risks of leukemia under the relative projection model were biased -27.1% for males and -43.4% for females. Thus, nonleukemia risks for 1 Sv from ages 18 to 65 (DRREF=2) increased from 1.91%/Sv to 2.68%/Sv among males and from 3.23%/Sv to 4.92%/Sv among females. Leukemia excess risk increased from 0.87%/Sv to 1.10/Sv among males and from 0.73%/Sv to 1.04/Sv among females. Bias was dependent on the gender, site, correction method, exposure profile and projection model considered. Future studies that use LSS data for US nuclear workers may be downwardly biased if lifetime risk projections are not adjusted for random and systematic errors

  18. Balancing the Trade-off Between Learning Prospects and Spillover Risks

    DEFF Research Database (Denmark)

    Perri, Alessandra; Andersson, Ulf; Nell, Phillip Christopher;

    2013-01-01

    This paper investigates local vertical linkages of foreign subsidiaries and the dual role of such linkages as conduits for learning as well as potential channels for spillovers to competitors. On the basis of data from 97 subsidiaries, we analyze the quality of such linkages under varying levels ...... find a curvilinear relationship between the extent of competitive pressure and the quality of local linkages confirming our argument of a trade-off between learning prospects and spillover risks. Furthermore, the level of subsidiary capabilities moderates this relationship....

  19. Low Dose Radiation Cancer Risks: Epidemiological and Toxicological Models

    Energy Technology Data Exchange (ETDEWEB)

    David G. Hoel, PhD

    2012-04-19

    The basic purpose of this one year research grant was to extend the two stage clonal expansion model (TSCE) of carcinogenesis to exposures other than the usual single acute exposure. The two-stage clonal expansion model of carcinogenesis incorporates the biological process of carcinogenesis, which involves two mutations and the clonal proliferation of the intermediate cells, in a stochastic, mathematical way. The current TSCE model serves a general purpose of acute exposure models but requires numerical computation of both the survival and hazard functions. The primary objective of this research project was to develop the analytical expressions for the survival function and the hazard function of the occurrence of the first cancer cell for acute, continuous and multiple exposure cases within the framework of the piece-wise constant parameter two-stage clonal expansion model of carcinogenesis. For acute exposure and multiple exposures of acute series, it is either only allowed to have the first mutation rate vary with the dose, or to have all the parameters be dose dependent; for multiple exposures of continuous exposures, all the parameters are allowed to vary with the dose. With these analytical functions, it becomes easy to evaluate the risks of cancer and allows one to deal with the various exposure patterns in cancer risk assessment. A second objective was to apply the TSCE model with varing continuous exposures from the cancer studies of inhaled plutonium in beagle dogs. Using step functions to estimate the retention functions of the pulmonary exposure of plutonium the multiple exposure versions of the TSCE model was to be used to estimate the beagle dog lung cancer risks. The mathematical equations of the multiple exposure versions of the TSCE model were developed. A draft manuscript which is attached provides the results of this mathematical work. The application work using the beagle dog data from plutonium exposure has not been completed due to the fact

  20. Effects of IL-10 haplotype and atomic bomb radiation exposure on gastric cancer risk.

    Science.gov (United States)

    Hayashi, Tomonori; Ito, Reiko; Cologne, John; Maki, Mayumi; Morishita, Yukari; Nagamura, Hiroko; Sasaki, Keiko; Hayashi, Ikue; Imai, Kazue; Yoshida, Kengo; Kajimura, Junko; Kyoizumi, Seishi; Kusunoki, Yoichiro; Ohishi, Waka; Fujiwara, Saeko; Akahoshi, Masazumi; Nakachi, Kei

    2013-07-01

    Gastric cancer (GC) is one of the cancers that reveal increased risk of mortality and incidence in atomic bomb survivors. The incidence of gastric cancer in the Life Span Study cohort of the Radiation Effects Research Foundation (RERF) increased with radiation dose (gender-averaged excess relative risk per Gy = 0.28) and remains high more than 65 years after exposure. To assess a possible role of gene-environment interaction, we examined the dose response for gastric cancer incidence based on immunosuppression-related IL-10 genotype, in a cohort study with 200 cancer cases (93 intestinal, 96 diffuse and 11 other types) among 4,690 atomic bomb survivors participating in an immunological substudy. Using a single haplotype block composed of four haplotype-tagging SNPs (comprising the major haplotype allele IL-10-ATTA and the minor haplotype allele IL-10-GGCG, which are categorized by IL-10 polymorphisms at -819A>G and -592T>G, +1177T>C and +1589A>G), multiplicative and additive models for joint effects of radiation and this IL-10 haplotyping were examined. The IL-10 minor haplotype allele(s) was a risk factor for intestinal type gastric cancer but not for diffuse type gastric cancer. Radiation was not associated with intestinal type gastric cancer. In diffuse type gastric cancer, the haplotype-specific excess relative risk (ERR) for radiation was statistically significant only in the major homozygote category of IL-10 (ERR = 0.46/Gy, P = 0.037), whereas estimated ERR for radiation with the minor IL-10 homozygotes was close to 0 and nonsignificant. Thus, the minor IL-10 haplotype might act to reduce the radiation related risk of diffuse-type gastric cancer. The results suggest that this IL-10 haplotyping might be involved in development of radiation-associated gastric cancer of the diffuse type, and that IL-10 haplotypes may explain individual differences in the radiation-related risk of gastric cancer. PMID:23772925

  1. Modeling of the radiative energy balance within a crop canopy for estimating evapotranspiration: Studies on a row planted soybean canopy

    International Nuclear Information System (INIS)

    The spatial distribution and density of the leaf area within a crop canopy were used to estimate the radiational environment and evapotranspiration. Morphological measurements were pursued on the soybean stands in the early stage of growth when the two-dimensional foliage distribution pattern existed. The rectangular tube model was used to calculate the light absorption by parallel row of crops both short-wave radiation (direct and diffuse solar radiation, and scattered radiation by plant elements) and long-wave radiation (emanated radiation from the sky, ground and leaves). The simulated profiles are in close agreement with the experimentally measured short-wave and net radiation data. The evapotranspiration of a row was calcuated using a simulated net radiation. The model calculation also agreed well with the evapotranspiration estimated by the Bowen ratio method

  2. Radiation dose, reproductive history, and breast cancer risk among Japanese A-bomb survivors

    International Nuclear Information System (INIS)

    Excess risk of female breast cancer is among the most comprehensively documented late effects of exposure to substantial doses of ionizing radiation, based on studies of medically irradiated populations and the survivors of the A-bombings of Hiroshima and Nagasaki. This study looks at the interaction of dose with epidemiological factors like age at first full-term pregnancy and family history of breast cancer, most closely associated with risk in epidemiological studies of non-irradiatied populations. 1 fig., 2 tabs

  3. What Becomes of Nuclear Risk Assessment in Light of Radiation Hormesis?

    OpenAIRE

    Cuttler, Jerry M.

    2006-01-01

    A nuclear probabilistic risk or safety assessment (PRA or PSA) is a scientific calculation that uses assumptions and models to determine the likelihood of plant or fuel repository failures and the corresponding releases of radioactivity. Estimated radiation doses to the surrounding population are linked inappropriately to risks of cancer death and congenital malformations. Even though PRAs use very pessimistic assumptions, they demonstrate that nuclear power plants and fuel repositories are v...

  4. Radiation dose, reproductive history, and breast cancer risk among Japanese A-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Land, C.E. [National Cancer Institute, Bethesda, MD (United States)

    1992-06-01

    Excess risk of female breast cancer is among the most comprehensively documented late effects of exposure to substantial doses of ionizing radiation, based on studies of medically irradiated populations and the survivors of the A-bombings of Hiroshima and Nagasaki. This study looks at the interaction of dose with epidemiological factors like age at first full-term pregnancy and family history of breast cancer, most closely associated with risk in epidemiological studies of non-irradiatied populations. 1 fig., 2 tabs.

  5. Perception of radiation dose and potential risks of computed tomography in emergency department medical personnel

    Science.gov (United States)

    Lee, Jin Hee; Kim, Kyuseok; Lee, Kyoung Ho; Kim, Kwang Pyo; Kim, Yu Jin; Park, Chanjong; Kang, Changwoo; Lee, Soo Hoon; Jeong, Jin Hee; Rhee, Joong Eui

    2015-01-01

    Objective Use of computed tomography (CT) continues to increase, but the relatively high radiation doses associated with CT have raised health concerns such as future risk of cancer. We investigated the level of awareness regarding radiation doses and possible risks associated with CT in medical personnel (MP). Methods This study was conducted from April to May 2012 and included physicians and nurses who worked in the emergency department of 17 training hospitals. The questionnaire included measurement of the effect of CT or radiography on health using a 10-point numerical rating scale, estimation of the radiation dose of one abdominal CT scan compared with one chest radiograph, and perception of the increased lifetime risk of cancer associated with CT. Results A total of 354 MP participated in this study: 142 nurses, 87 interns, 86 residents, and 39 specialists. Interns were less aware of the effects of CT or radiography on health than other physicians or nurses (mean±SD of 4.8±2.7, 5.9±2.7, 6.1±2.7, and 6.0±2.2 for interns, residents, specialists, and nurses, respectively; P<0.05). There was a significant difference in knowledge about the relative radiation dose of one abdominal CT scan compared with one chest radiograph between physicians and nurses (48.6% vs. 28.9% for physicians vs. nurses, P<0.05). MP perceived an increased risk of cancer from radiation associated with CT. Conclusion MP perceive the risk of radiation associated with CT, but their level of knowledge seems to be insufficient.

  6. Fluoride concentrations in the water of Maringá, Brazil, considering the benefit/risk balance of caries and fluorosis

    Directory of Open Access Journals (Sweden)

    Edmara Tatiely Pedroso BERGAMO

    2015-01-01

    Full Text Available Current Brazilian law regarding water fluoridation classification is dichotomous with respect to the risks of and benefits for oral diseases, and fluoride (F concentrations less than 0.6 or above 0.8 mg F/L are considered outside the normal limits. Thus, the law does not consider that both caries and fluorosis are dependent on the dosage and duration of fluoride exposure because they are both chronic diseases. Therefore, this study evaluated the quality of water fluoridation in Maringá, PR, Brazil, considering a new classification for the concentration of F in water the supply, based on the anticaries benefit and risk of fluorosis (CECOL/USP, 2011. Water samples (n = 325 were collected monthly over one year from 28 distribution water networks: 20 from treatment plants and 8 from artesian wells. F concentrations were determined using a specific ion electrode. The average F concentration was 0.77 mg F/L (ppm F, ranging from 0.44 to 1.22 mg F/L. Considering all of the water samples analyzed, 83.7% of them presented from 0.55 to 0.84 mg F/L, and according to the new classification used, they would provide maximum anticaries benefit with a low risk of fluorosis. This percentage was lower (75.4% in the water samples supplied from artesian wells than from those distributed by the treatment plant (86%. In conclusion, based on the new classification of water F concentrations, the quality of water fluoridation in Maringá is adequate and is within the range of the best balance between risk and benefit.

  7. Practical guidance for using rivaroxaban in patients with atrial fibrillation: balancing benefit and risk

    Directory of Open Access Journals (Sweden)

    Haas S

    2014-03-01

    Full Text Available Sylvia Haas,1 Christoph Bode,2 Bo Norrving,3 Alexander GG Turpie4 1Technical University Munich, Munich, Germany; 2Department of Cardiology and Angiology, University of Freiburg, Freiburg, Germany; 3Department of Clinical Neuroscience, Lund University Hospital, Lund, Sweden; 4Department of Medicine, McMaster University, Hamilton, Ontario, Canada Abstract: Rivaroxaban is a direct factor Xa inhibitor that is widely available to reduce the risk of stroke or systemic embolism in patients with nonvalvular atrial fibrillation and one or more risk factors for stroke. Rivaroxaban provides practical advantages compared with warfarin and other vitamin K antagonists, including a rapid onset of action, few drug interactions, no dietary interactions, a predictable anticoagulant effect, and no requirement for routine coagulation monitoring. However, questions have emerged relating to the responsible use of rivaroxaban in day-to-day clinical practice, including patient selection, dosing, treatment of patients with renal impairment, conversion from use of vitamin K antagonists to rivaroxaban and vice versa, coagulation tests, and management of patients requiring invasive procedures or experiencing bleeding or an ischemic event. This article provides practical recommendations relating to the use of rivaroxaban in patients with nonvalvular atrial fibrillation, based on clinical trial evidence, relevant guidelines, prescribing information, and the authors' clinical experience. Keywords: novel oral anticoagulants, direct factor Xa inhibitor, peri-interventional management, practical guidance, rivaroxaban, stroke prevention

  8. Balancing research and funding using value of information and portfolio tools for nanomaterial risk classification

    Science.gov (United States)

    Bates, Matthew E.; Keisler, Jeffrey M.; Zussblatt, Niels P.; Plourde, Kenton J.; Wender, Ben A.; Linkov, Igor

    2016-02-01

    Risk research for nanomaterials is currently prioritized by means of expert workshops and other deliberative processes. However, analytical techniques that quantify and compare alternative research investments are increasingly recommended. Here, we apply value of information and portfolio decision analysis—methods commonly applied in financial and operations management—to prioritize risk research for multiwalled carbon nanotubes and nanoparticulate silver and titanium dioxide. We modify the widely accepted CB Nanotool hazard evaluation framework, which combines nano- and bulk-material properties into a hazard score, to operate probabilistically with uncertain inputs. Literature is reviewed to develop uncertain estimates for each input parameter, and a Monte Carlo simulation is applied to assess how different research strategies can improve hazard classification. The relative cost of each research experiment is elicited from experts, which enables identification of efficient research portfolios—combinations of experiments that lead to the greatest improvement in hazard classification at the lowest cost. Nanoparticle shape, diameter, solubility and surface reactivity were most frequently identified within efficient portfolios in our results.

  9. Ultraviolet Radiation and Melanoma: AN Interdisciplinary Risk Assessment

    Science.gov (United States)

    Charache, Darryl H.

    1995-01-01

    A multidisciplinary study involving atmospheric, demographic, and epidemiologic disciplines has been conducted to investigate the relation between ultraviolet (UV) dose and melanoma incidence rate on a global scale. A multiple scattering radiative transfer model has been developed to estimate spectral irradiance and integrated biologically effective dose amounts in the UV-B and UV-A wavelength regime. Global maps of seasonally averaged and peak biologically effective dose on a 1^circ x 1^circ resolution have been created for significant land areas using satellite- and surface-derived atmospheric and topographic data sets. These maps have been coupled with worldwide melanoma incidence rates obtained from the International Agency for Research on Cancer (IARC) database and an ethnically-derived skin type classification system to estimate a "global" biological amplification factor (BAF) for males and females. With these BAFs, future estimates of incidence rates and number of additional melanoma cases that may be expected based on simulated increases in UV dose between the years 1980 -2000 can be estimated under simplifying atmospheric and demographic assumptions. Using worldwide melanoma rates and corresponding UV doses, BAFs of 1.67 and 1.26 were derived for white males and females, respectively. No significant relation was found for non-white skin types. Despite relatively low current incidence rates, projections indicate greater percentage changes in incidence rates at higher latitudes where downward trends in ozone are highest. Greater increases in total number of cases appear in countries having high white skin populations; the increase in total cases in these countries is due primarily to population size rather than estimated increases in UV dose. The integration of atmospheric, epidemiological, and demographic models in this study has established a framework that can be used to improve assessments when more data become available, and can be adapted to analyze

  10. Towards individualized dose constraints: Adjusting the QUANTEC radiation pneumonitis model for clinical risk factors

    DEFF Research Database (Denmark)

    Appelt, Ane L; Vogelius, Ivan R.; Farr, Katherina P.;

    2014-01-01

    factors, in order to enable individual risk prediction. The approach is validated in an independent dataset. Material and methods. The prevalence of risk factors in the patient populations underlying the QUANTEC analysis was estimated, and a previously published method to adjust dose......-response relationships for clinical risk factors was employed. Effect size estimates (odds ratios) for risk factors were drawn from a recently published meta-analysis. Baseline values for D50 and γ50 were found. The method was tested in an independent dataset (103 patients), comparing the predictive power of the dose......Background. Understanding the dose-response of the lung in order to minimize the risk of radiation pneumonitis (RP) is critical for optimization of lung cancer radiotherapy. We propose a method to combine the dose-response relationship for RP in the landmark QUANTEC paper with known clinical risk...

  11. Technical Evaluation of the NASA Model for Cancer Risk to Astronauts Due to Space Radiation

    Science.gov (United States)

    2012-01-01

    At the request of NASA, the National Research Council's (NRC's) Committee for Evaluation of Space Radiation Cancer Risk Model reviewed a number of changes that NASA proposes to make to its model for estimating the risk of radiation-induced cancer in astronauts. The NASA model in current use was last updated in 2005, and the proposed model would incorporate recent research directed at improving the quantification and understanding of the health risks posed by the space radiation environment. NASA's proposed model is defined by the 2011 NASA report Space Radiation Cancer Risk Projections and Uncertainties 2010 (Cucinotta et al., 2011). The committee's evaluation is based primarily on this source, which is referred to hereafter as the 2011 NASA report, with mention of specific sections or tables cited more formally as Cucinotta et al. (2011). The overall process for estimating cancer risks due to low linear energy transfer (LET) radiation exposure has been fully described in reports by a number of organizations. They include, more recently: (1) The "BEIR VII Phase 2" report from the NRC's Committee on Biological Effects of Ionizing Radiation (BEIR) (NRC, 2006); (2) Studies of Radiation and Cancer from the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, 2006), (3) The 2007 Recommendations of the International Commission on Radiological Protection (ICRP), ICRP Publication 103 (ICRP, 2007); and (4) The Environmental Protection Agency s (EPA s) report EPA Radiogenic Cancer Risk Models and Projections for the U.S. Population (EPA, 2011). The approaches described in the reports from all of these expert groups are quite similar. NASA's proposed space radiation cancer risk assessment model calculates, as its main output, age- and gender-specific risk of exposure-induced death (REID) for use in the estimation of mission and astronaut-specific cancer risk. The model also calculates the associated uncertainties in REID. The general approach for

  12. Balancing the health benefits and environmental risks of pharmaceuticals: Diclofenac as an example.

    Science.gov (United States)

    Acuña, V; Ginebreda, A; Mor, J R; Petrovic, M; Sabater, S; Sumpter, J; Barceló, D

    2015-12-01

    Pharmaceuticals are designed to improve human and animal health, but even the most beneficial pharmaceuticals might raise some questions concerning the consequences of exposure to non-target organisms. To illustrate this situation and using diclofenac as a case-study, we analyze global consumption and occurrence data to identify hot spots of consumption without occurrence data, review the scientific literature on the harmful environmental effects to determine whether the observed concentrations in freshwater are of environmental concern, summarize the current pharmaceutical and environmental policies to highlight policy gaps, and suggest a series of research and policy recommendations, which can be summarized as follows: we need to improve the current knowledge on occurrence in freshwaters to properly implement environmental policies (i), diclofenac might pose a risk to non-target organisms in freshwater (ii); the harmful effects that some pharmaceuticals may have on the environment are not always addressed by environmental policies (iii).

  13. The Swift Project Contamination Control Program: A Case Study of Balancing Cost, Schedule and Risk

    Science.gov (United States)

    Hansen, Patricia A.; Day, Diane T.; Secunda, Mark S.; Rosecrans, Glenn P.

    2004-01-01

    The Swift Observatory will be launched in early 2004 to examine the dynamic process of gamma ray burst (GRB) events. The multi-wavelength Observatory will study the GRB afterglow characteristics, which will help to answer fundamental questions about both the structure and the evolution of the universe. The Swift Observatory Contamination Control Program has been developed to aid in ensuring the success of the on-orbit performance of two of the primary instruments: the Ultraviolet and Optical Telescope (UVOT) and the X-Ray Telescope (XRT). During the design phase of the Observatory, the contamination control program evolved and trade studies were performed to assess the risk of contaminating the sensitive UVOT and XRT optics during both pre-launch testing and on-orbit operations, within the constraints of the overall program cost and schedule.

  14. Mitigating the risk of opioid abuse through a balanced undergraduate pain medicine curriculum

    Directory of Open Access Journals (Sweden)

    Morley-Forster PK

    2013-12-01

    Full Text Available Patricia K Morley-Forster,1,2 Joseph V Pergolizzi,3–5 Robert Taylor Jr,5 Robert A Axford-Gatley,6 Edward M Sellers71Department of Anesthesia and Perioperative Medicine, University of Western Ontario, London, ON, Canada; 2Outpatient Pain Clinic, St Joseph’s Hospital, London, ON, Canada; 3Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; 4Department of Pharmacology, Temple University School of Medicine, Philadelphia, PA, USA; 5NEMA Research Inc, Naples, FL, USA; 6Clinical Content and Editorial Services, Complete Healthcare Communications, Inc, Chadds Ford, PA, USA; 7DL Global Partners Inc, Toronto, ON, CanadaAbstract: Chronic pain is highly prevalent in the United States and Canada, occurring in an estimated 30% of the adult population. Despite its high prevalence, US and Canadian medical schools provide very little training in pain management, including training in the safe and effective use of potent analgesics, most notably opioids. In 2005, the International Association for the Study of Pain published recommendations for a core undergraduate pain management curriculum, and several universities have implemented pilot programs based on this curriculum. However, when outcomes have been formally assessed, these initiatives have resulted in only modest improvements in physician knowledge about chronic pain and its treatment. This article discusses strategies to improve undergraduate pain management curricula and proposes areas in which those efforts can be augmented. Emphasis is placed on opioids, which have great potency as analgesics but also substantial risks in terms of adverse events and the risk of abuse and addiction. The authors conclude that the most important element of an undergraduate pain curriculum is clinical experience under mentors who are capable of reinforcing didactic learning by modeling best practices.Keywords: chronic pain, curricular content, medical education, opioids, pain

  15. Balancing precision and risk: should multiple detection methods be analyzed separately in N-mixture models?

    Directory of Open Access Journals (Sweden)

    Tabitha A Graves

    Full Text Available Using multiple detection methods can increase the number, kind, and distribution of individuals sampled, which may increase accuracy and precision and reduce cost of population abundance estimates. However, when variables influencing abundance are of interest, if individuals detected via different methods are influenced by the landscape differently, separate analysis of multiple detection methods may be more appropriate. We evaluated the effects of combining two detection methods on the identification of variables important to local abundance using detections of grizzly bears with hair traps (systematic and bear rubs (opportunistic. We used hierarchical abundance models (N-mixture models with separate model components for each detection method. If both methods sample the same population, the use of either data set alone should (1 lead to the selection of the same variables as important and (2 provide similar estimates of relative local abundance. We hypothesized that the inclusion of 2 detection methods versus either method alone should (3 yield more support for variables identified in single method analyses (i.e. fewer variables and models with greater weight, and (4 improve precision of covariate estimates for variables selected in both separate and combined analyses because sample size is larger. As expected, joint analysis of both methods increased precision as well as certainty in variable and model selection. However, the single-method analyses identified different variables and the resulting predicted abundances had different spatial distributions. We recommend comparing single-method and jointly modeled results to identify the presence of individual heterogeneity between detection methods in N-mixture models, along with consideration of detection probabilities, correlations among variables, and tolerance to risk of failing to identify variables important to a subset of the population. The benefits of increased precision should be weighed

  16. Cancer risk at low doses of ionizing radiation: artificial neural networks inference from atomic bomb survivors.

    Science.gov (United States)

    Sasaki, Masao S; Tachibana, Akira; Takeda, Shunichi

    2014-05-01

    Cancer risk at low doses of ionizing radiation remains poorly defined because of ambiguity in the quantitative link to doses below 0.2 Sv in atomic bomb survivors in Hiroshima and Nagasaki arising from limitations in the statistical power and information available on overall radiation dose. To deal with these difficulties, a novel nonparametric statistics based on the 'integrate-and-fire' algorithm of artificial neural networks was developed and tested in cancer databases established by the Radiation Effects Research Foundation. The analysis revealed unique features at low doses that could not be accounted for by nominal exposure dose, including (i) the presence of a threshold that varied with organ, gender and age at exposure, and (ii) a small but significant bumping increase in cancer risk at low doses in Nagasaki that probably reflects internal exposure to (239)Pu. The threshold was distinct from the canonical definition of zero effect in that it was manifested as negative excess relative risk, or suppression of background cancer rates. Such a unique tissue response at low doses of radiation exposure has been implicated in the context of the molecular basis of radiation-environment interplay in favor of recently emerging experimental evidence on DNA double-strand break repair pathway choice and its epigenetic memory by histone marking. PMID:24366315

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

    DEFF Research Database (Denmark)

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

    2007-01-01

    A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow-up. A sign......A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow......-up. A significant association was seen between radiation dose and all-cause mortality [excess relative risk (ERR) 0.42 per Sv, 90% CI 0.07, 0.79; 18,993 deaths]. This was mainly attributable to a dose-related increase in all cancer mortality (ERR/Sv 0.97, 90% CI 0.28, 1.77; 5233 deaths). Among 31 specific types...... of malignancies studied, a significant association was found for lung cancer (ERR/Sv 1.86, 90% CI 0.49, 3.63; 1457 deaths) and a borderline significant (P = 0.06) association for multiple myeloma (ERR/Sv 6.15, 90% CI cancers (ERR/Sv 1.96, 90% CI -0.26, 5.90; 328...

  18. Radiation exposure and mortality risk from CT and PET imaging of patients with malignant lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Nievelstein, R.A.J.; Kwee, T.C.; Beek, F.J.A.; Mali, W.P.T.M. [University Medical Center, Department of Radiology (E 01.132), Utrecht (Netherlands); Quarles van Ufford, H.M.E. [Medical Center Haaglanden, Department of Radiology, The Hague (Netherlands); Bierings, M.B. [University Medical Center, Department of Pediatric Hematology, Utrecht (Netherlands); Ludwig, I. [University Medical Center, Department of Hematology, Utrecht (Netherlands); Klerk, J.M.H. de [Meander Medical Center, Department of Nuclear Medicine, Amersfoort (Netherlands); Bruin, P.W. de; Geleijns, J. [University Medical Center, Department of Radiology, Leiden (Netherlands)

    2012-09-15

    To quantify radiation exposure and mortality risk from computed tomography (CT) and positron emission tomography (PET) imaging with {sup 18}F-fluorodeoxyglucose ({sup 18}F-FDG) in patients with malignant lymphoma (Hodgkin's disease [HD] or non-Hodgkin's lymphoma [NHL]). First, organ doses were assessed for a typical diagnostic work-up in children with HD and adults with NHL. Subsequently, life tables were constructed for assessment of radiation risks, also taking into account the disease-related mortality. In children with HD, cumulative effective dose from medical imaging ranged from 66 mSv (newborn) to 113 mSv (15 years old). In adults with NHL the cumulative effective dose from medical imaging was 97 mSv. Average fractions of radiation-induced deaths for children with HD [without correction for disease-related mortality in brackets] were 0.4% [0.6%] for boys and 0.7% [1.1%] for girls, and for adults with NHL 0.07% [0.28%] for men and 0.09% [0.37%] for women. Taking into account the disease-related reduction in life expectancy of patients with malignant lymphoma results in a higher overall mortality but substantial lower incidence of radiation induced deaths. The modest radiation risk that results from imaging with CT and {sup 18}F-FDG PET can be considered as justified, but imaging should be performed with care, especially in children. (orig.)

  19. Radiation exposure and mortality risk from CT and PET imaging of patients with malignant lymphoma

    International Nuclear Information System (INIS)

    To quantify radiation exposure and mortality risk from computed tomography (CT) and positron emission tomography (PET) imaging with 18F-fluorodeoxyglucose (18F-FDG) in patients with malignant lymphoma (Hodgkin's disease [HD] or non-Hodgkin's lymphoma [NHL]). First, organ doses were assessed for a typical diagnostic work-up in children with HD and adults with NHL. Subsequently, life tables were constructed for assessment of radiation risks, also taking into account the disease-related mortality. In children with HD, cumulative effective dose from medical imaging ranged from 66 mSv (newborn) to 113 mSv (15 years old). In adults with NHL the cumulative effective dose from medical imaging was 97 mSv. Average fractions of radiation-induced deaths for children with HD [without correction for disease-related mortality in brackets] were 0.4% [0.6%] for boys and 0.7% [1.1%] for girls, and for adults with NHL 0.07% [0.28%] for men and 0.09% [0.37%] for women. Taking into account the disease-related reduction in life expectancy of patients with malignant lymphoma results in a higher overall mortality but substantial lower incidence of radiation induced deaths. The modest radiation risk that results from imaging with CT and 18F-FDG PET can be considered as justified, but imaging should be performed with care, especially in children. (orig.)

  20. A comparative study of space radiation organ doses and associated cancer risks using PHITS and HZETRN

    Science.gov (United States)

    Bahadori, Amir A.; Sato, Tatsuhiko; Slaba, Tony C.; Shavers, Mark R.; Semones, Edward J.; Van Baalen, Mary; Bolch, Wesley E.

    2013-10-01

    NASA currently uses one-dimensional deterministic transport to generate values of the organ dose equivalent needed to calculate stochastic radiation risk following crew space exposures. In this study, organ absorbed doses and dose equivalents are calculated for 50th percentile male and female astronaut phantoms using both the NASA High Charge and Energy Transport Code to perform one-dimensional deterministic transport and the Particle and Heavy Ion Transport Code System to perform three-dimensional Monte Carlo transport. Two measures of radiation risk, effective dose and risk of exposure-induced death (REID) are calculated using the organ dose equivalents resulting from the two methods of radiation transport. For the space radiation environments and simplified shielding configurations considered, small differences (cosmic ray (GCR) boundary condition, compensating errors are observed, indicating that comparisons between the integral measurements of complex radiation environments and code calculations can be misleading. Code-to-code benchmarks allow for the comparison of differential quantities, such as secondary particle differential fluence, to provide insight into differences observed in integral quantities for particular components of the GCR spectrum.

  1. Development of radiation risk assessment simulator using system dynamics methodology

    International Nuclear Information System (INIS)

    The potential magnitudes of radionuclide releases under severe accident loadings and offsite consequences as well as the overall risk (the product of accident frequencies and consequences) are analyzed and evaluated quantitatively in this study. The system dynamics methodology has been applied to predict the time-dependent behaviors such as feedback and dependency as well as to model uncertain behavior of complex physical system. It is used to construct the transfer mechanisms of time dependent radioactivity concentration and to evaluate them. Dynamic variations of radio activities are simulated by considering several effects such as deposition, weathering, washout, re-suspension, root uptake, translocation, leaching, senescence, intake, and excretion of soil. The time-dependent radio-ecological model applicable to Korean specific environment has been developed in order to assess the radiological consequences following the short-term deposition of radio-nuclides during severe accidents nuclear power plant. An ingestion food chain model can estimate time dependent radioactivity concentrations in foodstuffs. And it is also shown that the system dynamics approach is useful for analyzing the phenomenon of the complex system as well as the behavior of structure values with respect to time. The output of this model (Bq ingested per Bq m-2 deposited) may be multiplied by the deposition and a dose conversion factor (Gy Bq-1) to yield organ-specific doses. The model may be run deterministically to yield a single estimate or stochastic distributions by 'Monte-Carlo' calculation that reflects uncertainty of parameter and model uncertainties. The results of this study may contribute to identifying the relative importance of various parameters occurred in consequence analysis, as well as to assessing risk reduction effects in accident management. (author)

  2. Space Radiation Cancer Risk Projections for Exploration Missions: Uncertainty Reduction and Mitigation

    Science.gov (United States)

    Cucinotta, Francis; Badhwar, Gautam; Saganti, Premkumar; Schimmerling, Walter; Wilson, John; Peterson, Leif; Dicello, John

    2002-01-01

    In this paper we discuss expected lifetime excess cancer risks for astronauts returning from exploration class missions. For the first time we make a quantitative assessment of uncertainties in cancer risk projections for space radiation exposures. Late effects from the high charge and energy (HZE) ions present in the galactic cosmic rays including cancer and the poorly understood risks to the central nervous system constitute the major risks. Methods used to project risk in low Earth orbit are seen as highly uncertain for projecting risks on exploration missions because of the limited radiobiology data available for estimating HZE ion risks. Cancer risk projections are described as a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Monte-Carlo sampling from subjective error distributions represents the lack of knowledge in each factor to quantify risk projection overall uncertainty. Cancer risk analysis is applied to several exploration mission scenarios. At solar minimum, the number of days in space where career risk of less than the limiting 3% excess cancer mortality can be assured at a 95% confidence level is found to be only of the order of 100 days.

  3. Nutrients and Chemical Pollutants in Fish and Shellfish. Balancing Health Benefits and Risks of Regular Fish Consumption.

    Science.gov (United States)

    Domingo, José L

    2016-01-01

    Dietary patterns and lifestyle factors are clearly associated with at least five of the ten leading causes of death, including coronary heart disease, certain types of cancer, stroke, non-insulin insulin-dependent diabetes mellitus, and atherosclerosis. Concerning specifically fish and seafood consumption, its beneficial health effects in humans are clearly supported by an important number of studies performed in the last 30 years. These studies have repeatedly linked fish consumption, especially those species whose contents in omega-3 fatty acids are high, with healthier hearts in the aging population. The nutritional benefits of fish and seafood are also due to the content of high-quality protein, vitamins, as well as other essential nutrients. However, a number of studies, particularly investigations performed in recent years, have shown that the unavoidable presence of environmental contaminants in fish and shellfish can also mean a certain risk for the health of some consumers. While prestigious international associations as the American Heart Association have recommended eating fish at least two times (two servings a week), based on our own experimental results, as well as in results from other laboratories, we cannot be in total agreement with that recommendation. Although a regular consumption of most fish and shellfish species should not mean adverse health effects for the consumers, the specific fish and shellfish species consumed, the frequency of consumption, as well as the meal size, are essential issues for adequately balancing the health benefits and risks of regular fish consumption. PMID:25486051

  4. Risk factors for radiation-induced hypothyroidism: A Literature-Based Meta-Analysis

    DEFF Research Database (Denmark)

    Vogelius, Ivan R; Bentzen, Søren; Petersen, Peter M;

    2011-01-01

    BACKGROUND: A systematic overview and meta-analysis of studies reporting data on hypothyroidism (HT) after radiation therapy was conducted to identify risk factors for development of HT. METHODS: Published studies were identified from the PubMed and Embase databases and by hand-searching published...

  5. Extrapolating ecological risks of ionizing radiation from individuals to populations to ecosystems

    International Nuclear Information System (INIS)

    Approaches for protecting ecosystems from ionizing radiation are quite different from those used for protecting ecosystems from adverse effects of toxic chemicals. The methods used for chemicals are conceptually similar to those used to assess risks of chemicals to human health in that they focus on the protection of the most sensitive or most highly exposed individuals. The assumption is that if sensitive or maximally exposed species and life stages are protected, then ecosystems will be protected. Radiological protection standards, on the other hand, are explicitly premised on the assumption that organisms, populations and ecosystems all possess compensatory capabilities to allow them to survive in the face of unpredictable natural variation in their environments. These capabilities are assumed to persist in the face of at least some exposure to ionizing radiation. The prevailing approach to radiological protection was developed more than 30 years ago, at a time when the terms risk assessment and risk management were rarely used. The expert review approach used to derive radiological protection standards is widely perceived to be inconsistent with the open, participatory approach that prevails today for the regulation of toxic chemicals. The available data for environmental radionuclides vastly exceeds that available for any chemical. Therefore, given an understanding of dose-response relationships for radiation effects and exposures for individual organisms, it should be possible to develop methods for quantifying effects of radiation on populations. A tiered assessment scheme as well as available population models that could be used for the ecological risk assessment of radionuclides is presented. (author)

  6. Radiation exposure and mortality risk from CT and PET imaging of patients with malignant lymphoma

    NARCIS (Netherlands)

    Nievelstein, R. A. J.; van Ufford, H. M. E. Quarles; Kwee, T. C.; Bierings, M. B.; Ludwig, I.; Beek, F. J. A.; de Klerk, J. M. H.; Mali, W. P. Th. M.; de Bruin, P. W.; Geleijns, J.

    2012-01-01

    Objective To quantify radiation exposure and mortality risk from computed tomography (CT) and positron emission tomography (PET) imaging with F-18-fluorodeoxyglucose (F-18-FDG) in patients with malignant lymphoma (Hodgkin's disease [HD] or non-Hodgkin's lymphoma [NHL]). Methods First, organ doses we

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

    Science.gov (United States)

    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.

  8. Overview of epidemiologic studies of radiation and cancer risk based on medical series

    International Nuclear Information System (INIS)

    Epidemiologic studies of individuals exposed to ionizing radiation for medical reasons have made important contributions to understanding of the relationship between such radiation and subsequent cancer risk. In this paper the strengths and limitations of medical studies are considered and their future potential usefulness is discussed. Studies may be broadly classified into two types, namely, those of individuals exposed for therapeutic purposes such as the study of ankylosing spondylytics and those of individuals exposed for diagnostic or examination purposes such as those of tuberculosis patients routinely examined by chest fluoroscopy. In general, studies of therapeutic exposures tend to involve high doses of radiation given at high dose rates and in a relatively small number of fractions, whereas studies of diagnostic exposures tend to involve relatively low doses, low dose rates and many fractions. However, these generalizations are not always true: for example, in the fluoroscopy studies some patients received doses to organs such as breast and lung which were substantially higher than those experienced in the atomic bomb survivors study and in a study of Israeli children treated with radiation for tinea capitis the average thyroid dose was reported to be low, and only about 0.09 gray. These studies illustrate one of the most important advantages of medical series, namely the variety of such studies in terms of the characteristics of the radiation involved (linear energy transfer characteristics, dose range, dose rate, and fractionation), the organs exposed and hence potentially at risk, and the characteristics of those exposed to such radiation

  9. Improved aerosol radiative properties as a foundation for solar geoengineering risk assessment

    Science.gov (United States)

    Dykema, J. A.; Keith, D. W.; Keutsch, F. N.

    2016-07-01

    Side effects resulting from the deliberate injection of sulfate aerosols intended to partially offset climate change have motivated the investigation of alternatives, including solid aerosol materials. Sulfate aerosols warm the tropical tropopause layer, increasing the flux of water vapor into the stratosphere, accelerating ozone loss, and increasing radiative forcing. The high refractive index of some solid materials may lead to reduction in these risks. We present a new analysis of the scattering efficiency and absorption of a range of candidate solid aerosols. We utilize a comprehensive radiative transfer model driven by updated, physically consistent estimates of optical properties. We compute the potential increase in stratospheric water vapor and associated longwave radiative forcing. We find that the stratospheric heating calculated in this analysis indicates some materials to be substantially riskier than previous work. We also find that there are Earth-abundant materials that may reduce some principal known risks relative to sulfate aerosols.

  10. Comparison of risks due to bisphenol A and radiation with trad-MCN assay

    International Nuclear Information System (INIS)

    Many kinds of synthetic chemicals have been being used for various purposes. Some of them are called 'environmental hormones' because they can disturb the endocrine system of organisms. Presently no technique is established for the quantitative assessment of biological risk of the environmental hormones. The pollen mother cells (PMC) of Tradescantia are very sensitive to chemical toxicants or ionizing radiation, and thus can be used as a biological end-point assessing their effect. Micronucleus frequencies in PMC showed a good dose- and concentration-response relationship for radiation and bisphenol A. From the dose-response relationship, it is possible to estimate the equivalent bisphenol A concentration, or vice versa. One μM/ml of bisphenol A is equivalent to 1.8 cGy of radiation in the induction of micronuclei. It is known from the result that Trad-MCN assay can be an excellent tool for detection of biological risk due to environmental toxicants or synthetic chemicals

  11. Risk of stillbirth in offspring of men exposed to ionising radiation

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamson, Seymour [Department of Zoology, University of Wisconsin, Madison, WI (United States). E-mail: sabraha2@facstaff.wisc.edu; Tawn, E.J. [Westlakes Research Institute, Moor Row, Cumbria (United Kingdom). E-mail: ejt@westlakes.ac.uk

    2001-06-01

    Radiation genetic risk models are employed to predict the frequency of radiation-related stillbirths to partners of occupationally exposed male workers, using the incidence data recently reported by Parker et al from an epidemiological study of Cumbrian births. Expanding on previously developed conservative risk estimates suggests that, of the 130 observed stillbirths to partners of male radiation workers, 0.3 cases would be attributable to paternal preconceptional irradiation, in contrast to the 17.5 (95% confidence interval: 3.1 to 31.9) cases predicted by Parker et al from their preferred dose-response model. The incompatibility of the results reported by Parker et al with those from other investigations, both epidemiological and experimental, and the inability of the study to consider a number of factors which might affect stillbirth rates, particularly those relating to the mother, make it difficult to accept that paternal irradiation received occupationally could have contributed to a detectable increase in stillbirths. (author)

  12. Impact of rocket propulsion technology on the radiation risk in missions to Mars

    Science.gov (United States)

    Durante, M.; Bruno, C.

    2010-10-01

    Exposure to cosmic radiation is today acknowledged as a major obstacle to human missions to Mars. In fact, in addition to the poor knowledge on the late effects of heavy ions in the cosmic rays, simple countermeasures are apparently not available. Shielding is indeed very problematic in space, because of mass problems and the high-energy of the cosmic rays, and radio-protective drugs or dietary supplements are not effective. However, the simplest countermeasure for reducing radiation risk is to shorten the duration time, particularly the transit time to Mars, where the dose rate is higher than on the planet surface. Here we show that using nuclear electric propulsion (NEP) rockets, the transit time could be substantially reduced to a point where radiation risk could be considered acceptable even with the current uncertainty on late effects.

  13. Multistage Carcinogenesis Modelling of Low and Protracted Radiation Exposure for Risk Assessment

    Science.gov (United States)

    Brugmans, M. J. P.; Bijwaard, H.

    Exposure to cosmic radiation in space poses an increased risk for radiation-induced cancer later in life. Modelling is essential to quantify these excess risks from low and protracted exposures to a mixture of radiation types, since they cannot be determined directly in epidemiological studies. Multistage carcinogenesis models provide a mechanistic basis for the extrapolation of epidemiological data to the regime that is relevant for radiation protection. In recent years, we have exploited the well-known two-mutation carcinogenesis model to bridge the gap between radiobiology and epidemiology. We have fitted this model to a number of animal and epidemiological data sets, using dose-response relationships for the mutational steps that are well established in cellular radiobiology. The methodology and implications for radiation risks are illustrated with analyses of two radiation-induced tumours: bone cancer from internal (high-LET and low-LET) emitters and lung cancer after radon exposure. For the risks of bone-seeking radionuclides (Ra-226, Sr-90, Pu-239), model fits to beagle data show that the dose-effect relationship for bone cancer at low intakes is linear-quadratic. This is due to a combination of equally strong linear dose-effects in the two subsequent mutational steps in the model. This supra-linear dose-effect relationship is also found in a model analysis of bone cancer in radium dial painters. This implies that at low intakes the risks from bone seekers are significantly lower than estimated from a linear extrapolation from high doses. Model analyses of radon-exposed rats and uranium miners show that lung-cancer induction is dominated by a linear radiation effect in the first mutational step. For two miner cohorts with significantly different lung cancer baselines a uniform description of the effect of radon is obtained in a joint analysis. This demonstrates the possibility to model risk transfer across populations. In addition to biologically based risk

  14. Transport calculations and accelerator experiments needed for radiation risk assessment in space

    International Nuclear Information System (INIS)

    The major uncertainties on space radiation risk estimates in humans are associated to the poor knowledge of the biological effects of low and high LET radiation, with a smaller contribution coming from the characterization of space radiation field and its primary interactions with the shielding and the human body. However, to decrease the uncertainties on the biological effects and increase the accuracy of the risk coefficients for charged particles radiation, the initial charged-particle spectra from the Galactic Cosmic Rays (GCRs) and the Solar Particle Events (SPEs), and the radiation transport through the shielding material of the space vehicle and the human body, must be belter estimated. Since it is practically impossible to measure all primary and secondary particles from all possible position-projectile-target-energy combinations needed for a correct risk assessment in space, accurate particle and heavy ion transport codes must be used. These codes are also needed when estimating the risk for radiation induced failures in advanced microelectronics, such as single-event effects, etc., and the efficiency of different shielding materials. It is therefore important that the models and transport codes will be carefully benchmarked and validated to make sure they fulfill preset accuracy criteria, e.g. to be able to predict particle fluence, dose and energy distributions within a certain accuracy. When validating the accuracy of the transport codes, both space and ground based accelerator experiments are needed. The efficiency of passive shielding and protection of electronic devices should also be tested in accelerator experiments and compared to simulations using different transport codes. In this paper different multipurpose particle and heavy ion transport codes will be presented, different concepts of shielding and protection discussed, as well as future accelerator experiments needed for testing and validating codes and shielding materials. (orig.)

  15. Single particle effects, Biostack, and risk evaluation - Studies on the radiation risk from Galactic cosmic rays

    Science.gov (United States)

    Curtis, Stanley B.

    1993-01-01

    The possible health risks posed by Galactic cosmic rays, especially the possible heightened cancer risk, are examined. The results of the Biostack studies of the biological effects of high-energy cosmic rays are discussed. The biological mechanisms involved in possible harm due to cosmic rays are considered.

  16. Radiation risk associated with mammography screening examinations for women younger than 50 years of age

    International Nuclear Information System (INIS)

    The target group of the German mammography screening program, conducted according to the European guidelines, is clearly defined: all women aged 50 to 69 years without evidence of breast cancer are invited to screening mammography every two years. In the present study the question was raised whether breast cancer screening by means of mammography is - from the point of view of radiation hygiene - justified also for women under 50 years of age. Based on current radio-epidemiological breast cancer studies, the excess lifetime risk (ELR) to incur or die from breast cancer of a 40, 45 and 50 year old woman was assessed. Different risk models were used to estimate the radiation risk, e.g. models given for the 'Life Span Study' of the atomic bomb survivors and the risk model given in the recent Biological Effects of Ionizing Radiation (BEIR) VII report. The benefit risk ratio was defined as the ratio of the number of 'saved lives' due to screening to the number of deaths due to 'radiation induced breast cancer'. All estimations were based on the assumption that screening is taking place up to the age of 69 years, with screening examinations being performed annually up to the age of 50 and every two years from the age of 50 onwards. The glandular dose per two-view mammography investigation was assumed to be 4 mGy. The benefit due to mammography screening was assumed to be 25% for all age groups. Assuming screening from the age of 40 or 45 years, the ELR of breast cancer is on average about 3.5 or 2 times as high compared to the ELR associated with screening starting from the age of 50 years. In comparison to the benefit risk ratio, which results for women participating in a mammography screening from the age of 50 years, the benefit risk ratio for women starting with screening already from the age of 40 or 45 years is reduced by a factor of 3 or 2. With the present data - with regard to both, the benefit and the radiation risk - it appears not to be justified to expose

  17. Radiation release and health effects lessons from the Three Mile Island incident: assessment of objective risks for emergency preparedness planning

    International Nuclear Information System (INIS)

    The accepted theories of radiation health effects are briefly discussed so that the Three Mile Island health effects estimations can be better understood. The author recommends that emergency response planners weigh the objective risks rather than the perceived risks of low-level radiation against those associated with evacuation of large population zones before a final plan is put into effect

  18. Problems and solutions in the estimation of genetic risks from radiation and chemicals

    International Nuclear Information System (INIS)

    Extensive investigations with mice on the effects of various physical and biological factors, such as dose rate, sex and cell stage, on radiation-induced mutation have provided an evaluation of the genetics hazards of radiation in man. The mutational results obtained in both sexes with progressive lowering of the radiation dose rate have permitted estimation of the mutation frequency expected under the low-level radiation conditions of most human exposure. Supplementing the studies on mutation frequency are investigations on the phenotypic effects of mutations in mice, particularly anatomical disorders of the skeleton, which allow an estimation of the degree of human handicap associated with the occurrence of parallel defects in man. Estimation of the genetic risk from chemical mutagens is much more difficult, and the research is much less advanced. Results on transmitted mutations in mice indicate a poor correlation with mutation induction in non-mammalian organisms

  19. The risks of leukaemia and other cancers in Seascale from radiation exposure

    International Nuclear Information System (INIS)

    Including new data in the radiation dose calculations for the Seascale study population of 1225 children and young persons, followed to 20 years of age or 1980, has, with modifications to dosimetric models, increased the predicted number of radiation-induced leukaemia resulting from Sallafield discharges from 0.01 to 0.016. Risk to the average child in the study, from the discharges, is now calculated as about 1 in 75,000 with a maximum risk of about 1 in 30,000 for children born in the mid-1950s. For the four fatal leukemias to be attributed to the Sellafield operations, the calculated average risk for all the children would have to be increased about 250 times. Estimate of the overall risk of radiation-induced leukaemia in the study population, from combined sources, has increased by less than 10% of the previous estimate and the total number of cases is still rounded to 0.1, as in R171. Risk to the average child is now calculated as about 1 in 12,250, about two thirds from natural background, 16% from Sellafield discharges, and 9% each from weapons fallout and medical exposure. (U.K.)

  20. Some statistical considerations related to the estimation of cancer risk following exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Statistical theory and methodology provide the logical structure for scientific inference about the cancer risk associated with exposure to ionizing radiation. Although much is known about radiation carcinogenesis, the risk associated with low-level exposures is difficult to assess because it is too small to measure directly. Estimation must therefore depend upon mathematical models which relate observed risks at high exposure levels to risks at lower exposure levels. Extrapolated risk estimates obtained using such models are heavily dependent upon assumptions about the shape of the dose-response relationship, the temporal distribution of risk following exposure, and variation of risk according to variables such as age at exposure, sex, and underlying population cancer rates. Expanded statistical models, which make explicit certain assumed relationships between different data sets, can be used to strengthen inferences by incorporating relevant information from diverse sources. They also allow the uncertainties inherent in information from related data sets to be expressed in estimates which partially depend upon that information. To the extent that informed opinion is based upon a valid assessment of scientific data, the larger context of decision theory, which includes statistical theory, provides a logical framework for the incorporation into public policy decisions of the informational content of expert opinion

  1. Organs at risk and target volumes: Definition for conformal radiation therapy in breast cancer

    International Nuclear Information System (INIS)

    Adjuvant radiotherapy is a standard component of breast cancer treatment. The addition of radiotherapy after breast conserving surgery has been shown to reduce local recurrence rate and improve long-term survival. Accurate delineation of target volumes and organs at risk is crucial to the quality of treatment planning and delivered accomplished with innovate technologies in radiation therapy. This allows the radiation beam to be shaped specifically to each individual patient's anatomy. Target volumes include the mammary gland and surgical bed in case of breast conserving surgery, the chest wall in case of mastectomy, and if indicated, regional lymph nodes (axillary, supra- and infra-clavicular and internal mammary). Organs at risk include lungs, thyroid, brachial plexus, heart, spinal cord and oesophagus. The aim of this article is to encourage the use of conformal treatment and delineation of target volumes and organs at risk and to describe specifically the definition of these volumes. (authors)

  2. Radiation-induced noncancer risks in interventional cardiology: optimisation of procedures and staff and patient dose reduction.

    Science.gov (United States)

    Sun, Zhonghua; AbAziz, Aini; Yusof, Ahmad Khairuddin Md

    2013-01-01

    Concerns about ionizing radiation during interventional cardiology have been increased in recent years as a result of rapid growth in interventional procedure volumes and the high radiation doses associated with some procedures. Noncancer radiation risks to cardiologists and medical staff in terms of radiation-induced cataracts and skin injuries for patients appear clear potential consequences of interventional cardiology procedures, while radiation-induced potential risk of developing cardiovascular effects remains less clear. This paper provides an overview of the evidence-based reviews of concerns about noncancer risks of radiation exposure in interventional cardiology. Strategies commonly undertaken to reduce radiation doses to both medical staff and patients during interventional cardiology procedures are discussed; optimisation of interventional cardiology procedures is highlighted.

  3. The impact on radiation risk estimates of effect modifiers and confounders

    International Nuclear Information System (INIS)

    We have conducted studies of the joint effects of radiation with other risk factors for liver, lung, and breast cancer in the cohort of Japanese survivors of the 1945 atomic bombings. Based on follow-up of 45,113 subjects from 1958 through 1994, of whom 592 developed lung cancer, we found the effects of smoking and radiation to be significantly non-multiplicative and consistent with additivity. Adjustment for smoking reduced the female:male ratio of radiation risk estimates for lung cancer in this cohort from 5.8 to 1.6, a ratio more similar to that for all solid cancers. We conducted cross sectional and case control studies within the A-bomb survivor cohort to assess the joint effects of radiation with hepatitis B virus (HBV) and C virus (HCV) infections on the etiology of liver cirrhosis and hepatocellular carcinoma (HCC). Our study of 268 pathologist-confirmed cirrhosis cases and 843 subjects without cirrhosis, found no relationship between A-bomb radiation and cirrhosis after adjustment for viral hepatitis. In terms of HCC, our study of 238 pathologist-confirmed cases and 894 controls showed super-multiplicative interaction between radiation and HCV infections. Our results suggest that while chronic radiation exposure acts as a complete carcinogen for HCC, acute irradiation may act in concert with an agent such as HCV that is associated with liver cell proliferation. Studies in progress of the joint effects of radiation with insulin-like growth factor 1 (IGF-1) and IGF Binding Protein 3 (IGFBP-3), and total estradiol on the etiology of breast cancer, a particularly radiogenic tumor, will also be discussed

  4. Predicting the Risk of Secondary Lung Malignancies Associated With Whole-Breast Radiation Therapy

    International Nuclear Information System (INIS)

    Purpose: The risk of secondary lung malignancy (SLM) is a significant concern for women treated with whole-breast radiation therapy after breast-conserving surgery for early-stage breast cancer. In this study, a biologically based secondary malignancy model was used to quantify the risk of secondary lung malignancies (SLMs) associated with several common methods of delivering whole-breast radiation therapy (RT). Methods and Materials: Both supine and prone computed tomography simulations of 15 women with early breast cancer were used to generate standard fractionated and hypofractionated whole-breast RT treatment plans for each patient. Dose–volume histograms (DVHs) of the ipsilateral breast and lung were calculated for each patient on each plan. A model of spontaneous and radiation-induced carcinogenesis was used to determine the relative risks of SLMs for the different treatment techniques. Results: A higher risk of SLMs was predicted for supine breast irradiation when compared with prone breast irradiation for both the standard fractionation and hypofractionation schedules (relative risk [RR] = 2.59, 95% confidence interval (CI) = 2.30–2.88, and RR = 2.68, 95% CI = 2.39–2.98, respectively). No difference in risk of SLMs was noted between standard fractionation and hypofractionation schedules in either the supine position (RR = 1.05, 95% CI = 0.97–1.14) or the prone position (RR = 1.01, 95% CI = 0.88–1.15). Conclusions: Compared with supine whole-breast irradiation, prone breast irradiation is associated with a significantly lower predicted risk of secondary lung malignancy. In this modeling study, fractionation schedule did not have an impact on the risk of SLMs in women treated with whole-breast RT for early breast cancer.

  5. The functional assessment Berg Balance Scale is better capable of estimating fall risk in the elderly than the posturographic Balance Stability System A avaliação funcional Berg Balance Scale é capaz de estimar melhor o risco de quedas em idosos do que a posturografia Balance Stability System

    Directory of Open Access Journals (Sweden)

    Vanessa Vieira Pereira

    2013-01-01

    Full Text Available The purpose of this study was to verify which instrument better identifies recurrent falls in the elderly. Ninety-eight old people, with an average age of 80±4 years, were submitted to an assessment of balance and fall risk by means of the Berg Balance Scale (BBS and the posturographic Balance Stability System (BSS. The BBS was correlated with the BSS (r=-0.27; p=0.008, age (r=-0.38; pA proposta do estudo foi verificar o instrumento que melhor identifica o risco de quedas recorrentes em idosos. O estudo incluiu 98 idosos, com média de idade de 80±4 anos, submetidos à avaliação do equilíbrio e risco de quedas por meio da Berg Balance Scale (BBS e da posturografia Balance Stability System (BSS. A BBS foi correlacionada com a BSS (r=-0,27; p=0,008, com a idade (r=-0,38; p<0,001 e com o número de quedas (r=-0,25; p=0,013. A análise de regressão logística mostrou que idosos classificados com risco de quedas na BBS apresentaram 2,5 (95%IC 1,08-5,78 mais chances de identificar quem teve duas quedas ou mais no último ano. A BBS identificou que quanto maior a idade pior é o equilíbrio funcional e demonstrou maior capacidade de identificar o risco de quedas sofridas no último ano quando comparada a BSS.

  6. Testicular cancer risk associated with occupational radiation exposure: a systematic literature review

    Energy Technology Data Exchange (ETDEWEB)

    Yousif, Lamya; Blettner, Maria; Hammer, Gael P; Zeeb, Hajo, E-mail: yousif@imbei.uni-mainz.d [Department of Epidemiology, Institute of Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center, Johannes Gutenberg-University Mainz, Obere Zahlbacher Strasse 69, 55131 Mainz (Germany)

    2010-09-15

    Testicular cancer is a rare disease, affecting mainly young men aged 15-49. There have been some recent reports that it might be associated with radiation exposure. We have systematically reviewed this topic. English-language articles published between 1990 and 2008 studying the relationship between occupational radiation exposure and testicular cancer were included. Risk of bias was assessed using a modified version of the EPHPP checklist. For ionising radiation we subdivided study populations into occupational groups. No pooled analysis was performed due to the heterogeneity of studies. Seven case-control and 30 cohort studies were included in the review. For radiation workers, one incidence study showed a significant increase and four showed no effect. Eight mortality studies did not indicate an effect while four showed a non-significant increase. Incidence among persons with military exposure was not increased in two studies and non-significantly increased in another two. Among aircrew studies, one showed no effect against five with slight increases. Medical exposure studies showed no increases. For EMF exposure, three studies showed no effect, two reported a significant and four a non-significant increase in incidence. Overall, there was very limited evidence for associations between occupational ionising radiation and testicular cancer, while there were some positive associations for EMF. Testicular cancer mortality is generally low and was not associated with radiation. New incidence studies are recommended to investigate the association between radiation exposure and testicular cancer where exposure is better specified and individually estimated. (review)

  7. Testicular cancer risk associated with occupational radiation exposure: a systematic literature review

    International Nuclear Information System (INIS)

    Testicular cancer is a rare disease, affecting mainly young men aged 15-49. There have been some recent reports that it might be associated with radiation exposure. We have systematically reviewed this topic. English-language articles published between 1990 and 2008 studying the relationship between occupational radiation exposure and testicular cancer were included. Risk of bias was assessed using a modified version of the EPHPP checklist. For ionising radiation we subdivided study populations into occupational groups. No pooled analysis was performed due to the heterogeneity of studies. Seven case-control and 30 cohort studies were included in the review. For radiation workers, one incidence study showed a significant increase and four showed no effect. Eight mortality studies did not indicate an effect while four showed a non-significant increase. Incidence among persons with military exposure was not increased in two studies and non-significantly increased in another two. Among aircrew studies, one showed no effect against five with slight increases. Medical exposure studies showed no increases. For EMF exposure, three studies showed no effect, two reported a significant and four a non-significant increase in incidence. Overall, there was very limited evidence for associations between occupational ionising radiation and testicular cancer, while there were some positive associations for EMF. Testicular cancer mortality is generally low and was not associated with radiation. New incidence studies are recommended to investigate the association between radiation exposure and testicular cancer where exposure is better specified and individually estimated. (review)

  8. Scatter radiation from chest radiographs: is there a risk to infants in a typical NICU?

    International Nuclear Information System (INIS)

    To evaluate the dose of scatter radiation to infants in a NICU in order to determine the minimal safe distance between isolettes. Dose secondary to scattered radiation from an acrylic phantom exposed to vertical and horizontal beam exposures at 56 kVp was measured at 93 cm and 125 cm from the center of the phantom. This corresponds to 2 and 3 ft between standard isolettes, respectively. For horizontal exposures, the dosimeter was placed directly behind a CR plate and scatter dose at 90-degrees and 135-degrees from the incident beam was also measured. Exposures were obtained at 160 mAs and the results were extrapolated to correspond to 2.5 mAs. Four measurements were taken at each point and averaged. At 125 cm and 93 cm there was minimal scatter compared to daily natural background radiation dose (8.493 μGy). Greatest scatter dose obtained from a horizontal beam exposure at 135 from the incident beam was still far below background radiation. Scatter radiation dose from a single exposure as well as cumulative scatter dose from numerous exposures is significantly below natural background radiation. Infants in neighboring isolettes are not at added risk from radiation scatter as long as the isolettes are separated by at least 2 ft. (orig.)

  9. Scatter radiation from chest radiographs: is there a risk to infants in a typical NICU?

    Energy Technology Data Exchange (ETDEWEB)

    Trinh, Angela M. [Albert Einstein/Yeshiva University, College of Medicine, Bronx, NY (United States); Schoenfeld, Alan H.; Levin, Terry L. [Montefiore Medical Center, Department of Radiology, Bronx, NY (United States)

    2010-05-15

    To evaluate the dose of scatter radiation to infants in a NICU in order to determine the minimal safe distance between isolettes. Dose secondary to scattered radiation from an acrylic phantom exposed to vertical and horizontal beam exposures at 56 kVp was measured at 93 cm and 125 cm from the center of the phantom. This corresponds to 2 and 3 ft between standard isolettes, respectively. For horizontal exposures, the dosimeter was placed directly behind a CR plate and scatter dose at 90-degrees and 135-degrees from the incident beam was also measured. Exposures were obtained at 160 mAs and the results were extrapolated to correspond to 2.5 mAs. Four measurements were taken at each point and averaged. At 125 cm and 93 cm there was minimal scatter compared to daily natural background radiation dose (8.493 {mu}Gy). Greatest scatter dose obtained from a horizontal beam exposure at 135 from the incident beam was still far below background radiation. Scatter radiation dose from a single exposure as well as cumulative scatter dose from numerous exposures is significantly below natural background radiation. Infants in neighboring isolettes are not at added risk from radiation scatter as long as the isolettes are separated by at least 2 ft. (orig.)

  10. Risk Factors for Cataract After Palladium-103 Ophthalmic Plaque Radiation Therapy

    International Nuclear Information System (INIS)

    Purpose: To examine how tumor characteristics and dose affect cataract development after plaque radiation therapy. Methods and Materials: Three hundred and eighty-four patients were diagnosed with uveal melanoma and treated with palladium-103 (103Pd) plaque radiation therapy. Of these, 282 (74%) inclusion met exclusion criteria for follow-up time, tumor location, and phakic status. Then patient-, ophthalmic-, and radiation-specific factors (patient age, diabetes, hypertension, tumor location, tumor dimensions, and lens dose) were examined (by a Cox proportional regression model) as predictors for the development of radiation-related cataract. Results: Radiation cataract developed in 76 (24%) of patients at a mean follow-up of 39.8 months (range, 1-192). Patients with anteriorly located tumors were noted to have a higher incidence of cataract at 43.0% (43 of 100 patients) vs. 18.1% (33 cataracts per 182 patients) for posteriorly located tumors (p <0.0001). However, multivariate Cox proportional modeling showed that increasing patient age at time of treatment (p for trend = 0.0003) and higher lens dose (p for trend = 0.001) were the best predictors (biomarkers) for radiation cataract. Conclusions: Although anterior tumor location, greater tumor height, and increased patient age (at treatment) were associated with significantly greater risk for radiation cataract, dose to lens was the most significant factor.

  11. An Integrated Approach to Risk-Based Post-Closure Safety Evaluation of Complex Radiation Exposure Situations in Radioactive Waste Disposal

    International Nuclear Information System (INIS)

    Embodying the safety of radioactive waste disposal requires the relevant safety criteria and the corresponding stylized methods to demonstrate its compliance with the criteria. This paper proposes a conceptual model of risk-based safety evaluation for integrating complex potential radiation exposure situations in radioactive waste disposal. For demonstrating compliance with a risk constraint, the approach deals with important exposure scenarios from the viewpoint of the receptor to estimate the resulting risk. For respective exposure situations, it considers the occurrence probabilities of the relevant exposure scenarios as their probability of giving rise to doses to estimate the total risk to a representative person by aggregating the respective risks. In this model, an exposure scenario is simply constructed with three components: radionuclide release, radionuclide migration and environment contamination, and interaction between the contaminated media and the receptor. A set of exposure scenarios and the representative person are established from reasonable combinations of the components, based on a balance of their occurrence probabilities and the consequences. In addition, the probability of an exposure scenario is estimated on the assumption that the initiating external factors influence release mechanisms and transport pathways, and its effect on the interaction between the environment and the receptor may be covered in terms of the representative person. This integrated approach enables a systematic risk assessment for complex exposure situations of radioactive waste disposal and facilitates the evaluation of compliance with risk constraints

  12. Relative risk analysis in regulating the use of radiation-emitting medical devices. A preliminary application

    Energy Technology Data Exchange (ETDEWEB)

    Jones, E.D.; Banks, W.W.; Altenbach, T.J.; Fischer, L.E. [Lawrence Livermore National Lab., CA (United States)

    1995-09-01

    This report describes a preliminary application of an analysis approach for assessing relative risks in the use of radiation- emitting medical devices. Results are presented on human-initiated actions and failure modes that are most likely to occur in the use of the Gamma Knife, a gamma irradiation therapy device. This effort represents an initial step in a US Nuclear Regulatory Commission (NRC) plan to evaluate the potential role of risk analysis in regulating the use of nuclear medical devices. For this preliminary application of risk assessment, the focus was to develop a basic process using existing techniques for identifying the most likely risk contributors and their relative importance. The approach taken developed relative risk rankings and profiles that incorporated the type and quality of data available and could present results in an easily understood form. This work was performed by the Lawrence Livermore National Laboratory for the NRC.

  13. Relative risk analysis in regulating the use of radiation-emitting medical devices. A preliminary application

    International Nuclear Information System (INIS)

    This report describes a preliminary application of an analysis approach for assessing relative risks in the use of radiation- emitting medical devices. Results are presented on human-initiated actions and failure modes that are most likely to occur in the use of the Gamma Knife, a gamma irradiation therapy device. This effort represents an initial step in a US Nuclear Regulatory Commission (NRC) plan to evaluate the potential role of risk analysis in regulating the use of nuclear medical devices. For this preliminary application of risk assessment, the focus was to develop a basic process using existing techniques for identifying the most likely risk contributors and their relative importance. The approach taken developed relative risk rankings and profiles that incorporated the type and quality of data available and could present results in an easily understood form. This work was performed by the Lawrence Livermore National Laboratory for the NRC

  14. Uncertainties in Estimates of the Risks of Late Effects from Space Radiation

    Science.gov (United States)

    Cucinotta, F. A.; Schimmerling, W.; Wilson, J. W.; Peterson, L. E.; Saganti, P.; Dicelli, J. F.

    2002-01-01

    The health risks faced by astronauts from space radiation include cancer, cataracts, hereditary effects, and non-cancer morbidity and mortality risks related to the diseases of the old age. Methods used to project risks in low-Earth orbit are of questionable merit for exploration missions because of the limited radiobiology data and knowledge of galactic cosmic ray (GCR) heavy ions, which causes estimates of the risk of late effects to be highly uncertain. Risk projections involve a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Within the linear-additivity model, we use Monte-Carlo sampling from subjective uncertainty distributions in each factor to obtain a Maximum Likelihood estimate of the overall uncertainty in risk projections. The resulting methodology is applied to several human space exploration mission scenarios including ISS, lunar station, deep space outpost, and Mar's missions of duration of 360, 660, and 1000 days. The major results are the quantification of the uncertainties in current risk estimates, the identification of factors that dominate risk projection uncertainties, and the development of a method to quantify candidate approaches to reduce uncertainties or mitigate risks. The large uncertainties in GCR risk projections lead to probability distributions of risk that mask any potential risk reduction using the "optimization" of shielding materials or configurations. In contrast, the design of shielding optimization approaches for solar particle events and trapped protons can be made at this time, and promising technologies can be shown to have merit using our approach. The methods used also make it possible to express risk management objectives in terms of quantitative objective's, i.e., the number of days in space without exceeding a given risk level within well defined confidence limits.

  15. Assessment of uncertainties in radiation-induced cancer risk predictions at clinically relevant doses

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, J. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts 02114 and Department of Physics, Ruprecht-Karls-Universität Heidelberg, Heidelberg 69117 (Germany); Moteabbed, M.; Paganetti, H., E-mail: hpaganetti@mgh.harvard.edu [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts 02114 and Harvard Medical School, Boston, Massachusetts 02114 (United States)

    2015-01-15

    Purpose: Theoretical dose–response models offer the possibility to assess second cancer induction risks after external beam therapy. The parameters used in these models are determined with limited data from epidemiological studies. Risk estimations are thus associated with considerable uncertainties. This study aims at illustrating uncertainties when predicting the risk for organ-specific second cancers in the primary radiation field illustrated by choosing selected treatment plans for brain cancer patients. Methods: A widely used risk model was considered in this study. The uncertainties of the model parameters were estimated with reported data of second cancer incidences for various organs. Standard error propagation was then subsequently applied to assess the uncertainty in the risk model. Next, second cancer risks of five pediatric patients treated for cancer in the head and neck regions were calculated. For each case, treatment plans for proton and photon therapy were designed to estimate the uncertainties (a) in the lifetime attributable risk (LAR) for a given treatment modality and (b) when comparing risks of two different treatment modalities. Results: Uncertainties in excess of 100% of the risk were found for almost all organs considered. When applied to treatment plans, the calculated LAR values have uncertainties of the same magnitude. A comparison between cancer risks of different treatment modalities, however, does allow statistically significant conclusions. In the studied cases, the patient averaged LAR ratio of proton and photon treatments was 0.35, 0.56, and 0.59 for brain carcinoma, brain sarcoma, and bone sarcoma, respectively. Their corresponding uncertainties were estimated to be potentially below 5%, depending on uncertainties in dosimetry. Conclusions: The uncertainty in the dose–response curve in cancer risk models makes it currently impractical to predict the risk for an individual external beam treatment. On the other hand, the ratio

  16. Enhanced Intestinal Tumor Multiplicity and Grade in vivo after HZE Exposure: Mouse Models for Space Radiation Risk Estimates

    OpenAIRE

    Trani, Daniela; Datta, Kamal; Doiron, Kathryn; Kallakury, Bhaskar; Fornace, Albert J., Jr.

    2010-01-01

    Carcinogenesis induced by space radiation is considered a major risk factor in manned interplanetary and other extended missions. The models presently used to estimate the risk for cancer induction following deep space radiation exposure are based on data from A-bomb survivor cohorts and do not account for important biological differences existing between high-linear energy transfer (LET) and low-LET-induced DNA damage. High-energy and charge (HZE) radiation, the main component of galactic co...

  17. SRP meeting: social and political implications of communicating radiation risk, Daresbury, Warrington, 20 June 2001

    International Nuclear Information System (INIS)

    The SRP held a very interesting meeting in June at the Daresbury Laboratory in Warrington on the social and political implications of communicating radiation risk. In today's risk-aware society, effective communication is just as important as the control measures introduced to prevent or restrict exposure. In relation to radiation protection, risk communicators had a hard job because of: Public dread Likelihood of risk intensification Perceived inequitable distribution of risks. The higher the uncertainty, the more wary people were likely to be. Julie cited the International Nuclear Events Scale (INES) as a possible tool for promoting a consistent message across all publics. This was because it aimed to put events into proper perspective and provide a common understanding amongst the nuclear community, the media and the public. Julie summed up by saying that the risk communication was not just any form of communication and the issue of communicating radiation risks involved special consideration. Further research established that the more information given to the local population, the more likely that they would deny that there was a problem. Denial could moderate beliefs or emotional reactions to a situation. This then affected their dose as they were more likely to adopt risky behaviour by eating contaminated food and entering contaminated areas. Avoiding the need to undertake safe behaviour reduced stress levels. Furthermore, people adopted beliefs to suit their situation. For example, some inhabitants of the affected areas became adapted to the radiation and actually felt worse outside the contaminated area. There was strong pressure for the maintenance of a situation which actually prevented appropriate precautions being taken. Peter concluded that there was often confusion over the details of technical information that sometimes might not help to prevent a course of action being taken. However on a positive note the research did find credence and positive

  18. Effects of exercise and nutrition on postural balance and risk of falling in elderly people with decreased bone mineral density : randomized controlled trial pilot study

    NARCIS (Netherlands)

    Swanenburg, Jaap; de Bruin, Eling Douwe; Stauffacher, Marguerite; Mulder, Theo; Uebelhart, Daniel

    2007-01-01

    Objective: To compare the effect of calcium/vitamin D supplements with a combination of calcium/vitamin D supplements and exercise/protein on risk of failing and postural balance. Design: Randomized clinical trial. Setting: University hospital physiotherapy department. Subjects: Twenty-four independ

  19. Case report: a balance training program using the Nintendo Wii Fit to reduce fall risk in an older adult with bilateral peripheral neuropathy.

    Science.gov (United States)

    Hakim, Renée Marie; Salvo, Charles J; Balent, Anthony; Keyasko, Michael; McGlynn, Deidre

    2015-02-01

    A recent systematic review supported the use of strength and balance training for older adults at risk for falls, and provided preliminary evidence for those with peripheral neuropathy (PN). However, the role of gaming systems in fall risk reduction was not explored. The purpose of this case report was to describe the use of the Nintendo® Wii™ Fit gaming system to train standing balance in a community-dwelling older adult with PN and a history of recurrent near falls. A 76-year-old patient with bilateral PN participated in 1 h of Nintendo® Wii™ Fit balance training, two times a week for 6 weeks. Examination was conducted using a Computerized Dynamic Posturography system (i.e. Sensory Organization Test (SOT), Limits of Stability (LOS), Adaptation Test (ADT) and Motor Control Test (MCT) and clinical testing with the Berg Balance Scale (BBS), Timed Up and Go (TUG), Activities-specific Balance Confidence (ABC) scale and 30-s Chair Stand. Following training, sensory integration scores on the SOT were unchanged. Maximum excursion abilities improved by a range of 37-86% on the LOS test. MCT scores improved for amplitude with forward translations and ADT scores improved for downward platform rotations. Clinical scores improved on the BBS (28/56-34/56), ABC (57.5-70.6%) and TUG (14.9-10.9 s) which indicated reduced fall risk. Balance training with a gaming system showed promise as a feasible, objective and enjoyable method to improve physical performance and reduce fall risk in an individual with PN. PMID:25515202

  20. The Australasian radiation protection society's position statement on risks from low levels of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Don, Higson; Ches, Mason; Andrew, McEwan; Peter, Burns; Riaz, Akber; Ron, Cameron; Pamela, Sykes; Joe, Young [Australasian Radiation Protection Society (Australia)

    2006-07-01

    At its Annual General Meeting in 2004, the Australasian Radiation Protection Society (A.R.P.S.) set up a working group to draft a statement of the Society's position on risks from low levels of exposure to ionizing radiation. The resulting position statement was adopted by the Society at its Annual General Meeting in 2005. Its salient features are as follows: First, there is insufficient evidence to establish a dose-effect relationship for doses that are less than a few tens of milli sieverts in a year. A linear extrapolation from higher dose levels should be assumed only for the purpose of applying regulatory controls. Secondly, estimates of collective dose arising from individual doses that are less than some tens of milli sieverts in a year should not be used to predict numbers of fatal cancers. Thirdly, the risk to an individual of doses significantly less than 100 micro sieverts in a year is so small, if it exists at all, that regulatory requirements to control exposure at this level are not warranted. (authors)

  1. Cancer Risk in Diagnostic Radiation Workers in Korea from 1996–2002

    Directory of Open Access Journals (Sweden)

    Jong-Won Kang

    2013-01-01

    Full Text Available This study was aimed to examine the association between the effective radiation dose of diagnostic radiation workers in Korea and their risk for cancer. A total of 36,394 diagnostic radiation workers (159,189 person-years were included in this study; the effective dose and cancer incidence were analyzed between the period 1996 and 2002. Median (range follow-up time was 5.5 (0.04–7 years in males and 3.75 (0.04–7 years in females. Cancer risk related to the average annual effective dose and exposure to more than 5 mSv of annual radiation dose were calculated by the Cox proportional hazard model adjusted for occupation and age at the last follow-up. The standardized incidence ratio of cancer in radiation workers showed strong healthy worker effects in both male and female workers. The relative risk of all cancers from exposure of the average annual effective dose in the highest quartile (upper 75% or more of radiation dose was 2.14 in male workers (95% CI: 1.48–3.10, p-trend: <0.0001 and 4.43 in female workers (95% CI: 2.17–9.04, p-trend: <0.0001, compared to those in the lower three quartiles of radiation exposure dose (less than upper 75% of radiation dose. Cancer risks of the brain (HR: 17.38, 95% CI: 1.05–287.8, p-trend: 0.04 and thyroid (HR: 3.88, 95% CI: 1.09–13.75, p-trend: 0.01 in female workers were significantly higher in the highest quartile group of radiation exposure compared to those in the lower three quartiles, and the risk of colon and rectum cancers in male workers showed a significantly increasing trend according to the increase of the average annual radiation dose (HR: 2.37, 95% CI: 0.99–5.67, p-trend: 0.02. The relative risk of leukemia in male workers and that of brain cancer in female workers were significantly higher in the group of people who had been exposed to more than 5 mSv/year than those exposed to less than 5 mSv/year (HR: 11.75, 95% CI: 1.08–128.20; HR: 63.11, 95% CI: 3.70–1,075.00, respectively

  2. Determining the value of reductions in radiation risk using the contingent valuation method

    International Nuclear Information System (INIS)

    A study was conducted to develop feasible methodology to obtain Won per man-rem conversion factor that can be used in regulatory analysis in Korea. A comparative analysis of the value placed on reductions in risks from occupational radiation exposure and car accidents was conducted to the employees in nuclear power plants and nuclear institutes in Korea. The double bounded dichotomous choice approach was used in the context of the contingent valuation method (CVM). A web-based on-line survey questionnaire was used to elicit willingness-to-pay(WTP) values for predefined 20% reductions of the risks. WTP for safety goods to reduce the risks were estimated and values of a statistical life were calculated from the mean WTPs. The mean value of statistical life was 2.41 billion Won for car accidents and 3.93 billion Won for radiation exposure. Conversion factor for radiation dose was calculated as 2.03 million Won per man-rem, which is not different from $2000/man-rem used in US NRC. CVM could be one of the efficient ways to value radiation exposure reduction in monetary term

  3. Peri-operative radiation exposure: Are overweight patients at increased risks?

    Science.gov (United States)

    Dalgleish, S; Hince, A; Finlayson, D F

    2015-12-01

    The aim of this study was to identify if there was a correlation between body mass index (BMI) and intra-operative radiation exposure. A retrospective review of 81 patients who had sliding hip screw fixation for femoral neck fractures in one year was completed, recording body mass index (BMI), screening time, dose area product (DAP), American Society of Anesthesiologists (ASA) grade, seniority of operating surgeon and complexity of the fracture configuration. There was a statistically significant correlation between dose area product and BMI. There was no statistically significant relationship between screening time and BMI. There was no statistical difference between ASA grade, seniority of surgeon, or complexity of fracture configuration and dose area product. Simulated stochastic risks were increased for overweight patients. Overweight patients are exposed to increased doses of radiation regardless of length of screening time. Surgeons and theatre staff should be aware of the increased radiation exposure during fixation of fractures in overweight patients and, along with radiographers, ensure steps are taken to minimise these risks. Whilst such radiation dosages may have little adverse effect for individual patients, these findings may be of more relevance and concern to staff that will be exposed to increased radiation. PMID:26492884

  4. Radiation exposure and radiation risk due to inhalation or ingestion of actinides

    International Nuclear Information System (INIS)

    On the basis of the lung model following the ICRP recommendations (ICRP 19) dose commitments and dose factors have been calculated for the lung, lymphatic tissue, bone and liver due to single uptake of radioactive nuclides by inhalation or ingestion. These calculations have been performed for the most important isotopes of thorium, uranium, neptunium, plutonium, americium, curium and for mixtures of plutonium. Analogies between dose and dose rate due to single and continuous intake of radioactive nuclides are discussed. Finally estimations of the collective and individual risk are made. (orig.)

  5. Uncertainties in estimates of the risks of late effects from space radiation

    Science.gov (United States)

    Cucinotta, F. A.; Schimmerling, W.; Wilson, J. W.; Peterson, L. E.; Saganti, P. B.; Dicello, J. F.

    2004-01-01

    Methods used to project risks in low-Earth orbit are of questionable merit for exploration missions because of the limited radiobiology data and knowledge of galactic cosmic ray (GCR) heavy ions, which causes estimates of the risk of late effects to be highly uncertain. Risk projections involve a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. Using the linear-additivity model for radiation risks, we use Monte-Carlo sampling from subjective uncertainty distributions in each factor to obtain an estimate of the overall uncertainty in risk projections. The resulting methodology is applied to several human space exploration mission scenarios including a deep space outpost and Mars missions of duration of 360, 660, and 1000 days. The major results are the quantification of the uncertainties in current risk estimates, the identification of factors that dominate risk projection uncertainties, and the development of a method to quantify candidate approaches to reduce uncertainties or mitigate risks. The large uncertainties in GCR risk projections lead to probability distributions of risk that mask any potential risk reduction using the "optimization" of shielding materials or configurations. In contrast, the design of shielding optimization approaches for solar particle events and trapped protons can be made at this time and promising technologies can be shown to have merit using our approach. The methods used also make it possible to express risk management objectives in terms of quantitative metrics, e.g., the number of days in space without exceeding a given risk level within well-defined confidence limits. Published by Elsevier Ltd on behalf of COSPAR.

  6. Retroperitoneal Sarcoma Target Volume and Organ at Risk Contour Delineation Agreement Among NRG Sarcoma Radiation Oncologists

    Energy Technology Data Exchange (ETDEWEB)

    Baldini, Elizabeth H., E-mail: ebaldini@partners.org [Department of Radiation Oncology, Dana-Farber Cancer Institute, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Abrams, Ross A. [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States); Bosch, Walter [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Roberge, David [Department of Radiation Oncology, Centre Hospitalier de l' Universite de Montreal, Montreal, Quebec (Canada); Haas, Rick L.M. [Department of Radiotherapy, Netherlands Cancer Institute, Amsterdam (Netherlands); Catton, Charles N. [Department of Radiation Oncology, Princess Margaret Cancer Centre, Toronto, Ontario (Canada); Indelicato, Daniel J. [Department of Radiation Oncology, University of Florida Medical Center, Jacksonville, Florida (United States); Olsen, Jeffrey R. [Department of Radiation Oncology, Washington University, St. Louis, Missouri (United States); Deville, Curtiland [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Chen, Yen-Lin [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Finkelstein, Steven E. [Translational Research Consortium, 21st Century Oncology, Scottsdale, Arizona (United States); DeLaney, Thomas F. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Wang, Dian [Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States)

    2015-08-01

    Purpose: The purpose of this study was to evaluate the variability in target volume and organ at risk (OAR) contour delineation for retroperitoneal sarcoma (RPS) among 12 sarcoma radiation oncologists. Methods and Materials: Radiation planning computed tomography (CT) scans for 2 cases of RPS were distributed among 12 sarcoma radiation oncologists with instructions for contouring gross tumor volume (GTV), clinical target volume (CTV), high-risk CTV (HR CTV: area judged to be at high risk of resulting in positive margins after resection), and OARs: bowel bag, small bowel, colon, stomach, and duodenum. Analysis of contour agreement was performed using the simultaneous truth and performance level estimation (STAPLE) algorithm and kappa statistics. Results: Ten radiation oncologists contoured both RPS cases, 1 contoured only RPS1, and 1 contoured only RPS2 such that each case was contoured by 11 radiation oncologists. The first case (RPS 1) was a patient with a de-differentiated (DD) liposarcoma (LPS) with a predominant well-differentiated (WD) component, and the second case (RPS 2) was a patient with DD LPS made up almost entirely of a DD component. Contouring agreement for GTV and CTV contours was high. However, the agreement for HR CTVs was only moderate. For OARs, agreement for stomach, bowel bag, small bowel, and colon was high, but agreement for duodenum (distorted by tumor in one of these cases) was fair to moderate. Conclusions: For preoperative treatment of RPS, sarcoma radiation oncologists contoured GTV, CTV, and most OARs with a high level of agreement. HR CTV contours were more variable. Further clarification of this volume with the help of sarcoma surgical oncologists is necessary to reach consensus. More attention to delineation of the duodenum is also needed.

  7. Radiation dose measurement and risk estimation for paediatric patients undergoing micturating cystourethrography.

    Science.gov (United States)

    Sulieman, A; Theodorou, K; Vlychou, M; Topaltzikis, T; Kanavou, D; Fezoulidis, I; Kappas, C

    2007-09-01

    Micturating cystourethrography (MCU) is considered to be the gold-standard method used to detect and grade vesicoureteric reflux (VUR) and show urethral and bladder abnormalities. It accounts for 30-50% of all fluoroscopic examinations in children. Therefore, it is crucial to define and optimize the radiation dose received by a child during MCU examination, taking into account that children have a higher risk of developing radiation-induced cancer than adults. This study aims to quantify and evaluate, by means of thermoluminescence dosimetry (TLD), the radiation dose to the newborn and paediatric populations undergoing MCU using fluoroscopic imaging. Evaluation of entrance surface dose (ESD), organ and surface dose to specific radiosensitive organs was carried out. Furthermore, the surface dose to the co-patient, i.e. individuals helping in the support, care and comfort of the children during the examination, was evaluated in order to estimate the level of risk. 52 patients with mean age of 0.36 years who had undergone MCU using digital fluoroscopy were studied. ESD, surface doses to thyroid, testes/ovaries and co-patients were measured with TLDs. MCU with digital equipment and fluoroscopy-captured image technique can reduce the radiation dose by approximately 50% while still obtaining the necessary diagnostic information. Radiographic exposures were made in cases of the presence of reflux or of the difficulty in evaluating a finding. The radiation surface doses to the thyroid and testes are relatively low, whereas the radiation dose to the co-patient is negligible. The risks associated with MCU for patients and co-patients are negligible. The results of this study provide baseline data to establish reference dose levels for MCU examination in very young patients.

  8. Estimated risk of radiation-induced cancer from paediatric chest CT: two-year cohort study

    Energy Technology Data Exchange (ETDEWEB)

    Niemann, Tilo [Cantonal Hospital Baden, Department of Radiology, Baden (Switzerland); University Lille Nord de France, Department of Thoracic Imaging, Hospital Calmette, Lille (France); Colas, Lucie; Santangelo, Teresa; Faivre, Jean Baptiste; Remy, Jacques; Remy-Jardin, Martine [University Lille Nord de France, Department of Thoracic Imaging, Hospital Calmette, Lille (France); Roser, Hans W.; Bremerich, Jens [University of Basel Hospital, Clinic of Radiology and Nuclear Medicine, Medical Physics, Basel (Switzerland)

    2015-03-01

    The increasing absolute number of paediatric CT scans raises concern about the safety and efficacy and the effects of consecutive diagnostic ionising radiation. To demonstrate a method to evaluate the lifetime attributable risk of cancer incidence/mortality due to a single low-dose helical chest CT in a two-year patient cohort. A two-year cohort of 522 paediatric helical chest CT scans acquired using a dedicated low-dose protocol were analysed retrospectively. Patient-specific estimations of radiation doses were modelled using three different mathematical phantoms. Per-organ attributable cancer risk was then estimated using epidemiological models. Additional comparison was provided for naturally occurring risks. Total lifetime attributable risk of cancer incidence remains low for all age and sex categories, being highest in female neonates (0.34%). Summation of all cancer sites analysed raised the relative lifetime attributable risk of organ cancer incidence up to 3.6% in female neonates and 2.1% in male neonates. Using dedicated scan protocols, total lifetime attributable risk of cancer incidence and mortality for chest CT is estimated low for paediatric chest CT, being highest for female neonates. (orig.)

  9. Magnitude estimate of occupational risks located in a radiative facility and its main health impacts

    International Nuclear Information System (INIS)

    The work routine of Radiopharmacy Center (CR) personnel of the Institute of Energy Research and Nuclear (IPEN / CNEN-SP) includes singularities not exist in other professions. Relevant examples to this study can be cited: exposure to physical, chemical, biological hazards, to accidents and ergonomic risks. The objective of this study is to conduct a quantitative and qualitative evaluation of occupational exposure existing in the workplace and its impact on the health of occupationally exposed individuals (IOE's). The proposed methodology was based on systematic observation and a questionnaire to the managers of each practice held at CR. The evaluation process involved three steps: a) characterization of exposure; b) identification of the main points of exposure and possible routes of exposure; c) quantifying of exposure. Seventeen occupational agents related to the tasks of different groups of IOE's were identified. Ionizing radiation (physical risk) and the situations that cause stress (ergonomic risk) had the highest frequencies. According to the applied methodology risks was considered mostly acceptable. Quantification of exposure was basically referring to physical risk agent (Ionizing radiation), because it is a radioactive installation. Based on the records analyzed, not was observed health risks to workers arising from the activities undertaken

  10. Radiation-Induced Rib Fractures After Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors and Dose-Volume Relationship

    Energy Technology Data Exchange (ETDEWEB)

    Asai, Kaori [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Shioyama, Yoshiyuki, E-mail: shioyama@radiol.med.kyushu-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Nonoshita, Takeshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yoshitake, Tadamasa [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Ohnishi, Kayoko [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan); Terashima, Kotaro; Matsumoto, Keiji [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Hirata, Hideki [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)

    2012-11-01

    Purpose: The purpose of this study was to clarify the incidence, the clinical risk factors, and the dose-volume relationship of radiation-induced rib fracture (RIRF) after hypofractionated stereotactic body radiation therapy (SBRT). Methods and Materials: One hundred sixteen patients treated with SBRT for primary or metastatic lung cancer at our institution, with at least 6 months of follow-up and no previous overlapping radiation exposure, were included in this study. To determine the clinical risk factors associated with RIRF, correlations between the incidence of RIRF and the variables, including age, sex, diagnosis, gross tumor volume diameter, rib-tumor distance, and use of steroid administration, were analyzed. Dose-volume histogram analysis was also conducted. Regarding the maximum dose, V10, V20, V30, and V40 of the rib, and the incidences of RIRF were compared between the two groups divided by the cutoff value determined by the receiver operating characteristic curves. Results: One hundred sixteen patients and 374 ribs met the inclusion criteria. Among the 116 patients, 28 patients (46 ribs) experienced RIRF. The estimated incidence of rib fracture was 37.7% at 3 years. Limited distance from the rib to the tumor (<2.0 cm) was the only significant risk factor for RIRF (p = 0.0001). Among the dosimetric parameters used for receiver operating characteristic analysis, the maximum dose showed the highest area under the curve. The 3-year estimated risk of RIRF and the determined cutoff value were 45.8% vs. 1.4% (maximum dose, {>=}42.4 Gy or less), 51.6% vs. 2.0% (V40, {>=}0.29 cm{sup 3} or less), 45.8% vs. 2.2% (V30, {>=}1.35 cm{sup 3} or less), 42.0% vs. 8.5% (V20, {>=}3.62 cm{sup 3} or less), or 25.9% vs. 10.5% (V10, {>=}5.03 cm{sup 3} or less). Conclusions: The incidence of RIRF after hypofractionated SBRT is relatively high. The maximum dose and high-dose volume are strongly correlated with RIRF.

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

    DEFF Research Database (Denmark)

    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...... describes the design, methods and results of descriptive analyses of the study. The main analyses included 407,391 nuclear industry workers employed for at least 1 year in a participating facility who were monitored individually for external radiation exposure and whose doses resulted predominantly from...

  12. Risks of low-LET radiation as given in BEIR-III and previous reports

    International Nuclear Information System (INIS)

    This report presents the conclusions of a review of the report ΣThe Effects on Populations of Exposure to Low Levels of Ionizing RadiationΣ, BEIR-III, published by the U.S. National Academy of Sciences in 1980 and other related reports. The committee concludes that, in as far as the estimates of risk from low-LET radiation are concerned, the BEIR-III report does not provide any new data that might suggest that the present dose limits promulgated by the AECB should be changed

  13. Radiation. A buzz word for excessive fears

    International Nuclear Information System (INIS)

    The necessity of accepting that risk is an inherent part of daily life and also of acquiring a sense of perspective with respect to such risks, especially with respect to radiation, is discussed. Estimations of radiation risks are examined and compared to other risk factors such as overweight and cigarette smoking. It is stated that public perception of radiation has a direct bearing on the use of nuclear power, that balancing risks and benefits must become a standard approach to evaluating environmental matters and that the present crisis in confidence over energy requires this approach. (UK)

  14. Decreased Risk of Radiation Pneumonitis With Incidental Concurrent Use of Angiotensin-Converting Enzyme Inhibitors and Thoracic Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kharofa, Jordan [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Cohen, Eric P. [Department of Medicine, Division of Nephrology, Medical College of Wisconsin, Milwaukee, WI (United States); Tomic, Rade [Department of Medicine, Division of Pulmonology, Medical College of Wisconsin, Milwaukee, WI (United States); Xiang Qun [Division of Biostatistics, Medical College of Wisconsin, Milwaukee, WI (United States); Gore, Elizabeth, E-mail: Egore@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2012-09-01

    Purpose: Angiotensin-converting enzyme (ACE) inhibitors have been shown to mitigate radiation-induced lung injury in preclinical models. The aim of this study was to evaluate whether ACE inhibitors decrease the risk of radiation pneumonitis in lung cancer patients receiving thoracic irradiation. Methods and Materials: Patients with Stage I through III small-cell and non-small-cell lung cancer treated definitively with radiation from 2004-2009 at the Clement J. Zablocki Veterans Affairs Medical Center were retrospectively reviewed. Acute pulmonary toxicity was quantified within 6 months of completion of treatment according to the Common Terminology Criteria for Adverse Events version 4. The use of ACE inhibitors, nonsteroidal anti-inflammatory drugs, inhaled glucocorticosteroids, statins, and angiotensin receptor blockers; dose-volume histogram parameters; and patient factors were assessed for association with Grade 2 or higher pneumonitis. Results: A total of 162 patients met the criteria for inclusion. The majority of patients had Stage III disease (64%) and received concurrent chemotherapy (61%). Sixty-two patients were identified as ACE inhibitor users (38%). All patients had acceptable radiation plans based on dose-volume histogram constraints (V20 [volume of lung receiving at least 20 Gy] {<=}37% and mean lung dose {<=}20 Gy) with the exception of 2 patients who did not meet both criteria. Grade 2 or higher pulmonary toxicity occurred in 12 patients (7.4%). The rate of Grade 2 or higher pneumonitis was lower in ACE inhibitor users vs. nonusers (2% vs. 11%, p = 0.032). Rates of Grade 2 or higher pneumonitis were significantly increased in patients aged greater than 70 years (16% vs. 2%, p = 0.005) or in whom V5 (volume of lung receiving at least 5 Gy) was 50% or greater (13% vs. 4%, p = 0.04). V10 (volume of lung receiving at least 10 Gy), V20, V30 (volume of lung receiving at least 30 Gy), and mean lung dose were not independently associated with Grade 2 or

  15. The radiation risks for patients undergoing electrophysiology treatment of atrial fibrillation

    International Nuclear Information System (INIS)

    Full text: Atrial Fibrillation (AF) Ablations are complex electrophysiology (EP) procedures that have the potential to deliver significant radiation risk to the patient. The nature of AF is such that many patients require more than one procedure before a 'successful' outcome is achieved. This analysis aims to provide a better understanding of the radiation risks involved in EP treatment of AF. Methods Records for imaging procedures performed between January 1997 and May 2011 were reviewed. Analysis identified 439 AF ablation procedures on 293 patients (71 % male, median age 58, range 21-85). In total, these patients underwent 866 separate cardiac diagnostic, interventional, electrophysiology and device implant procedures. Effective Dose (E) estimates were derived for all procedures. 35% of patients had> I AF procedure (I patient undergoing 5). Actuarial analysis suggests freedom from return for follow-up AF ablation at 5 years of 65%. Reviewing all cardiac imaging histories for the 293 patients shows 60% had> I procedure (5% having >4) and 44% underwent cardiac procedures other than AF ablations. E for individual procedures ranged to 28 mSv with cumulative E for AF and all cardiac procedures ranging to 38 mSv and 80 mSv respectively. Many patients also underwent CT procedures to acquire 3D datasets for use in AF ablations (risk not assessed here). These findings suggest that the true radiation risk associated with AF ablation treatment is greater than that reported for an individual procedure. Every effort must therefore be taken to pursue techniques and technologies that limit radiation risk in these procedures.

  16. Overview of Graphical User Interface for ARRBOD (Acute Radiation Risk and BRYNTRN Organ Dose Projection)

    Science.gov (United States)

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

    Solar particle events (SPEs) pose the risk of acute radiation sickness (ARS) to astronauts be-cause organ doses from large SPEs may reach critical levels during extra vehicular activities (EVAs) or lightly shielded spacecraft. NASA has developed an organ dose projection model of Baryon transport code (BRYNTRN) with an output data processing module of SUMDOSE, and a probabilistic model of acute radiation risk (ARR). BRYNTRN code operation requires extensive input preparation, and the risk projection models of organ doses and ARR take the output from BRYNTRN as an input to their calculations. With a graphical user interface (GUI) to handle input and output for BRYNTRN, these response models can be connected easily and correctly to BRYNTRN in a user-friendly way. The GUI for the Acute Radiation Risk and BRYNTRN Organ Dose (ARRBOD) projection code provides seamless integration of input and output manipulations required for operations of the ARRBOD modules: BRYNTRN, SUMDOSE, and the ARR probabilistic response model. The ARRBOD GUI is intended for mission planners, radiation shield designers, space operations in the mission operations direc-torate (MOD), and space biophysics researchers. Assessment of astronauts' organ doses and ARS from the exposure to historically large SPEs is in support of mission design and opera-tion planning to avoid ARS and stay within the current NASA short-term dose limits. The ARRBOD GUI will serve as a proof-of-concept for future integration of other risk projection models for human space applications. We present an overview of the ARRBOD GUI prod-uct, which is a new self-contained product, for the major components of the overall system, subsystem interconnections, and external interfaces.

  17. Uncertainties in estimating health risks associated with exposure to ionising radiation

    International Nuclear Information System (INIS)

    The information for the present discussion on the uncertainties associated with estimation of radiation risks and probability of disease causation was assembled for the recently published NCRP Report No. 171 on this topic. This memorandum provides a timely overview of the topic, given that quantitative uncertainty analysis is the state of the art in health risk assessment and given its potential importance to developments in radiation protection. Over the past decade the increasing volume of epidemiology data and the supporting radiobiology findings have aided in the reduction of uncertainty in the risk estimates derived. However, it is equally apparent that there remain significant uncertainties related to dose assessment, low dose and low dose-rate extrapolation approaches (e.g. the selection of an appropriate dose and dose-rate effectiveness factor), the biological effectiveness where considerations of the health effects of high-LET and lower-energy low-LET radiations are required and the transfer of risks from a population for which health effects data are available to one for which such data are not available. The impact of radiation on human health has focused in recent years on cancer, although there has been a decided increase in the data for noncancer effects together with more reliable estimates of the risk following radiation exposure, even at relatively low doses (notably for cataracts and cardiovascular disease). New approaches for the estimation of hereditary risk have been developed with the use of human data whenever feasible, although the current estimates of heritable radiation effects still are based on mouse data because of an absence of effects in human studies. Uncertainties associated with estimation of these different types of health effects are discussed in a qualitative and semi-quantitative manner as appropriate. The way forward would seem to require additional epidemiological studies, especially studies of low dose and low dose

  18. Estimating the risks of cancer mortality and genetic defects resulting from exposures to low levels of ionizing radiation

    International Nuclear Information System (INIS)

    Estimators for calculating the risk of cancer and genetic disorders induced by exposure to ionizing radiation have been recommended by the US National Academy of Sciences Committee on the Biological Effects of Ionizing Radiations, the UN Scientific Committee on the Effects of Atomic Radiation, and the International Committee on Radiological Protection. These groups have also considered the risks of somatic effects other than cancer. The US National Council on Radiation Protection and Measurements has discussed risk estimate procedures for radiation-induced health effects. The recommendations of these national and international advisory committees are summarized and compared in this report. Based on this review, two procedures for risk estimation are presented for use in radiological assessments performed by the US Department of Energy under the National Environmental Policy Act of 1969 (NEPA). In the first procedure, age- and sex-averaged risk estimators calculated with US average demographic statistics would be used with estimates of radiation dose to calculate the projected risk of cancer and genetic disorders that would result from the operation being reviewed under NEPA. If more site-specific risk estimators are needed, and the demographic information is available, a second procedure is described that would involve direct calculation of the risk estimators using recommended risk-rate factors. The computer program REPCAL has been written to perform this calculation and is described in this report. 25 references, 16 tables

  19. Technical Evaluation of the NASA Model for Cancer Risk to Astronauts Due to Space Radiation

    Science.gov (United States)

    2012-01-01

    At the request of NASA, the National Research Council's (NRC's) Committee for Evaluation of Space Radiation Cancer Risk Model1 reviewed a number of changes that NASA proposes to make to its model for estimating the risk of radiation-induced cancer in astronauts. The NASA model in current use was last updated in 2005, and the proposed model would incorporate recent research directed at improving the quantification and understanding of the health risks posed by the space radiation environment. NASA's proposed model is defined by the 2011 NASA report Space Radiation Cancer Risk Projections and Uncertainties--2010 . The committee's evaluation is based primarily on this source, which is referred to hereafter as the 2011 NASA report, with mention of specific sections or tables. The overall process for estimating cancer risks due to low linear energy transfer (LET) radiation exposure has been fully described in reports by a number of organizations. The approaches described in the reports from all of these expert groups are quite similar. NASA's proposed space radiation cancer risk assessment model calculates, as its main output, age- and gender-specific risk of exposure-induced death (REID) for use in the estimation of mission and astronaut-specific cancer risk. The model also calculates the associated uncertainties in REID. The general approach for estimating risk and uncertainty in the proposed model is broadly similar to that used for the current (2005) NASA model and is based on recommendations by the National Council on Radiation Protection and Measurements. However, NASA's proposed model has significant changes with respect to the following: the integration of new findings and methods into its components by taking into account newer epidemiological data and analyses, new radiobiological data indicating that quality factors differ for leukemia and solid cancers, an improved method for specifying quality factors in terms of radiation track structure concepts as

  20. Sensitivity of the Tropical Atmosphere Energy Balance to ENSO-Related SST Changes: How Well Can We Quantify Hydrologic and Radiative Responses?

    Science.gov (United States)

    Robertson, Franklin R.; Fitzjarrald, Dan; Sohn, Byung-Ju; Arnold, James E. (Technical Monitor)

    2001-01-01

    The continuing debate over feedback mechanisms governing tropical sea surface temperatures (SSTs) and tropical climate in general has highlighted the diversity of potential checks and balances within the climate system. Competing feedbacks due to changes in surface evaporation, water vapor, and cloud long- and shortwave radiative properties each may serve critical roles in stabilizing or destabilizing the climate system. It is also intriguing that even those climate variations having origins internal to the climate system-- changes in ocean heat transport for example, apparently require complementary equilibrating effects by changes in atmospheric energy fluxes. Perhaps the best observational evidence of this is the relatively invariant nature of tropically averaged net radiation exiting the top-of-atmosphere (TOA) as measured by broadband satellite sensors over the past two decades. Thus, analyzing how these feedback mechanisms are operating within the context of current interannual variability may offer considerable insight for anticipating future climate change. In this paper we focus on how fresh water and radiative fluxes over the tropical oceans change during ENSO warm and cold events and how these changes affect the tropical energy balance. At present, ENSO remains the most prominent known mode of natural variability at interannual time scales. Although great advances have been made in understanding this phenomenon and realizing prediction skill over the past decade, our ability to document the coupled water and energy changes observationally and to represent them in climate models seems far from settled (Soden, 2000 J Climate). Our analysis makes use a number of data bases, principally those derived from space-based measurements, to explore systematic changes in rainfall, evaporation, and surface and top-of-atmosphere (TOA) radiative fluxes, A reexamination of the Langley 8-Year Surface Radiation Budget data set reveals errors in the surface longwave

  1. Health Risks From Low Doses and Low Dose-Rates of Ionizing Radiation. Session 5: Future of Radiation Protection Regulations.

    Science.gov (United States)

    Cool, Donald A

    2016-03-01

    The system of radiological protection is a prospective approach to protection of individuals in all exposure situations. It must be applied equitably across all age groups and all populations. This is a very different circumstance from dose assessment for a particular individual where the unique characteristics of the individual and the exposure can be taken into account. Notwithstanding the ongoing discussions on the possible shape of the dose response at low doses and dose rates, the prospective system of protection has therefore historically used a linear assumption as a pragmatic, prudent and protective approach. These radiation protection criteria are not intended to be a demarcation between "safe" and "unsafe" and are the product of a risk-informed judgement that includes inputs from science, ethics, and experience. There are significant implications for different dose response relationships. A linear model allows for equal treatment of an exposure, irrespective of the previously accumulated exposure. In contrast, other models would predict different implications. Great care is therefore needed in separating the thinking around risk assessment from risk management, and prospective protection for all age groups and genders from retrospective assessment for a particular individual. In the United States, the prospective regulatory structure functions effectively because of assumptions that facilitate independent treatment of different types of exposures, and which provide pragmatic and prudent protection. While the a linear assumption may, in fact, not be consistent with the biological reality, the implications of a different regulatory model must be considered carefully. PMID:26808877

  2. Health risks associated with residential exposure to extremely low frequency electromagnetic radiation.

    Science.gov (United States)

    Lamarine, R J; Narad, R A

    1992-10-01

    Extremely low frequency electromagnetic radiation has received considerable attention recently as a possible threat to the health of persons living near high tension electric power lines, distribution substations, and even in close proximity to common household electric appliances. Results of epidemiological and laboratory research are examined to assess risks associated with magnetic fields generated by extremely low frequency electromagnetic sources. Health risks associated with such fields include a wide variety of ills ranging from disruption of normal circadian rhythms to childhood cancers. Risk assessment has been particularly difficult to determine in light of an ostensible lack of a dose-response relationship. Current media sensation fueled in part by an equivocal position adopted by the United States Environmental Protection Agency has contributed to the controversy. Recommendations for prudent avoidance of possible dangers are presented along with policy implications concerning health risks associated with magnetic fields.

  3. The Brazilian Cardioprotective Nutritional Program to reduce events and risk factors in secondary prevention for cardiovascular disease: study protocol (The BALANCE Program Trial).

    Science.gov (United States)

    Weber, Bernardete; Bersch-Ferreira, Ângela Cristine; Torreglosa, Camila Ragne; Ross-Fernandes, Maria Beatriz; da Silva, Jacqueline Tereza; Galante, Andrea Polo; Lara, Enilda de Sousa; Costa, Rosana Perim; Soares, Rafael Marques; Cavalcanti, Alexandre Biasi; Moriguchi, Emilio H; Bruscato, Neide M; Kesties; Vivian, Lilian; Schumacher, Marina; de Carli, Waldemar; Backes, Luciano M; Reolão, Bruna R; Rodrigues, Milena P; Baldissera, Dúnnia M B; Tres, Glaucia S; Lisbôa, Hugo R K; Bem, João B J; Reolão, Jose B C; Deucher, Keyla L A L; Cantarelli, Maiara; Lucion, Aline; Rampazzo, Daniela; Bertoni, Vanessa; Torres, Rosileide S; Verríssimo, Adriana O L; Guterres, Aldair S; Cardos, Andrea F R; Coutinho, Dalva B S; Negrão, Mayara G; Alencar, Mônica F A; Pinho, Priscila M; Barbosa, Socorro N A A; Carvalho, Ana P P F; Taboada, Maria I S; Pereira, Sheila A; Heyde, Raul V; Nagano, Francisca E Z; Baumgartner, Rebecca; Resende, Fernanda P; Tabalipa, Ranata; Zanini, Ana C; Machado, Michael J R; Araujo, Hevila; Teixeira, Maria L V; Souza, Gabriela C; Zuchinali, Priccila; Fracasso, Bianca M; Ulliam, Karen; Schumacher, Marina; Pierotto, Moara; Hilário, Thamires; Carlos, Daniele M O; Cordeiro, Cintia G N C; Carvalho, Daniele A; Gonçalves, Marília S; Vasconcelos, Valdiana B; Bosquetti, Rosa; Pagano, Raira; Romano, Marcelo L P; Jardim, César A; de Abreu, Bernardo N A; Marcadenti, Aline; Schmitt, Alessandra R; Tavares, Angela M V; Faria, Christiane C; Silva, Flávia M; Fink, Jaqueline S; El Kik, Raquel M; Prates, Clarice F; Vieira, Cristiane S; Adorne, Elaine F; Magedanz, Ellen H; Chieza, Fernanda L; Silva, Ingrid S; Teixeira, Joise M; Trescastro, Eduardo P; Pellegrini, Lívia A; Pinto, Jéssika C; Telles, Cristina T; Sousa, Antonio C S; Almeida, Andreza S; Costa, Ariane A; Carmo, José A C; Silva, Juliana T; Alves, Luciana V S; Sales, Saulo O C; Ramos, Maria E M; Lucas, Marilia C S; Damiani, Monica; Cardoso, Patricia C; Ramos, Salvador S; Dantas, Clenise F; Lopes, Amanda G; Cabral, Ana M P; Lucena, Ana C A; Medeiros, Auriene L; Terceiro, Bernardino B; Leda, Neuma M F S; Baía, Sandra R D; Pinheiro, Josilene M F; Cassiano, Alexandra N; Melo, Andressa N L; Cavalcanti, Anny K O; Souza, Camila V S; Queiroz, Dayanna J M; Farias, Hercilla N C F; Souza, Larissa C F; Santos, Letícia S; Lima, Luana R M; Hoffmann, Meg S; Ribeiro, Átala S Silva; Vasconcelos, Daniel F; Dutra, Eliane S; Ito, Marina K; Neto, José A F; Santos, Alexsandro F; Sousa, Rosângela M L; Dias, Luciana Pereira P; Lima, Maria T M A; Modanesi, Victor G; Teixeira, Adriana F; Estrada, Luciana C N C D; Modanesi, Paulo V G; Gomes, Adriana B L; Rocha, Bárbara R S; Teti, Cristina; David, Marta M; Palácio, Bruna M; Junior, Délcio G S; Faria, Érica H S; Oliveira, Michelle C F; Uehara, Rose M; Sasso, Sandramara; Moreira, Annie S B; Cadinha, Ana C A H; Pinto, Carla W M; Castilhos, Mariana P; Costa, Mariana; Kovacs, Cristiane; Magnoni, Daniel; Silva, Quênia; Germini, Michele F C A; da Silva, Renata A; Monteiro, Aline S; dos Santos, Karina G; Moreira, Priscila; Amparo, Fernanda C; Paiva, Catharina C J; Poloni, Soraia; Russo, Diana S; Silveira, Izabele V; Moraes, Maria A; Boklis, Mirena; Cardoso, Quinto I; Moreira, Annie S B; Damaceno, Aline M S; Santos, Elisa M; Dias, Glauber M; Pinho, Cláudia P S; Cavalcanti, Adrilene C; Bezerra, Amanda S; Queiroga, Andrey V; Rodrigues, Isa G; Leal, Tallita V; Sahade, Viviane; Amaral, Daniele A; Souza, Diana S; Araújo, Givaldo A; Curvello, Karine; Heine, Manuella; Barretto, Marília M S; Reis, Nailson A; Vasconcelos, Sandra M L; Vieira, Danielly C; Costa, Francisco A; Fontes, Jessica M S; Neto, Juvenal G C; Navarro, Laís N P; Ferreira, Raphaela C; Marinho, Patrícia M; Abib, Renata Torres; Longo, Aline; Bertoldi, Eduardo G; Ferreira, Lauren S; Borges, Lúcia R; Azevedo, Norlai A; Martins, Celma M; Kato, Juliana T; Izar, Maria C O; Asoo, Marina T; de Capitani, Mariana D; Machado, Valéria A; Fonzar, Waléria T; Pinto, Sônia L; Silva, Kellen C; Gratão, Lúcia H A; Machado, Sheila D; de Oliveira, Susane R U; Bressan, Josefina; Caldas, Ana P S; Lima, Hatanne C F M; Hermsdorff, Helen H M; Saldanha, Tânia M; Priore, Sílvia E; Feres, Naoel H; Neves, Adila de Queiroz; Cheim, Loanda M G; Silva, Nilma F; Reis, Silvia R L; Penafort, Andreza M; de Queirós, Ana Paula O; Farias, Geysa M N; de los Santos, Mônica L P; Ambrozio, Cíntia L; Camejo, Cirília N; dos Santos, Cristiano P; Schirmann, Gabriela S; Boemo, Jorge L; Oliveira, Rosane E C; Lima, Súsi M B; Bortolini, Vera M S; Matos, Cristina H; Barretta, Claiza; Specht, Clarice M; de Souza, Simone R; Arruda, Cristina S; Rodrigues, Priscila A; Berwanger, Otávio

    2016-01-01

    This article reports the rationale for the Brazilian Cardioprotective Nutritional Program (BALANCE Program) Trial. This pragmatic, multicenter, nationwide, randomized, concealed, controlled trial was designed to investigate the effects of the BALANCE Program in reducing cardiovascular events. The BALANCE Program consists of a prescribed diet guided by nutritional content recommendations from Brazilian national guidelines using a unique nutritional education strategy, which includes suggestions of affordable foods. In addition, the Program focuses on intensive follow-up through one-on-one visits, group sessions, and phone calls. In this trial, participants 45 years or older with any evidence of established cardiovascular disease will be randomized to the BALANCE or control groups. Those in the BALANCE group will receive the afore mentioned program interventions, while controls will be given generic advice on how to follow a low-fat, low-energy, low-sodium, and low-cholesterol diet, with a view to achieving Brazilian nutritional guideline recommendations. The primary outcome is a composite of death (any cause), cardiac arrest, acute myocardial infarction, stroke, myocardial revascularization, amputation for peripheral arterial disease, or hospitalization for unstable angina. A total of 2468 patients will be enrolled in 34 sites and followed up for up to 48 months. If the BALANCE Program is found to decrease cardiovascular events and reduce risk factors, this may represent an advance in the care of patients with cardiovascular disease.

  4. The impact of radiation dose and fractionation on the risk factor of radiation pneumonitis on four radiation therapy oncology group (RTOG) lung cancer trials

    International Nuclear Information System (INIS)

    Purpose/Objective: To assess the relationship between total dose of radiation delivered, the fractionation scheme used, age, and Karnofsky Performance Status (KPS) on the risk of moderate to severe (≥ Grade 2) radiation pneumonitis in patients treated with radiotherapy alone for lung cancer on four RTOG Trials. Materials and Methods: Between February of 1984 and April of 1989, 1701 patients with clinically localized (I-IIIb) lung cancer were entered on clinical trials employing radiotherapy alone. Twelve hundred and forty-seven patients were entered on RTOG 8311 or 8407 (phase I/II trials) and 454 patients were entered on RTOG 8321 or 8403 (phase III trials). RTOG 8403 and 8321 patients received once-a-day irradiation to 60 Gy. Patients treated on RTOG 8407 were treated with a concomitant boost technique in a non-randomized fashion to 64.8, 69.6, 74.4 or 79.2 Gy. Patients treated on RTOG 8407 were treated with a concomitant boost technique in a non-randomized fashion to 63 Gy or 70.2 Gy. All patients were assessed for the incidence of Grade 2-5, radiation pneumonitis. One hundred and seven (6%) of patients were either ineligible or canceled (n=60), or were excluded because of incomplete data (n=47). The factors evaluated included total dose of radiation, the fractionation scheme, age and pre-treatment KPS. Patients treated to doses ≥ 72 Gy were considered to have received high doses (72.0 - 81.6 Gy), while the remaining patients treated to doses < 72 Gy (57.6 - 71.9 Gy) were considered to have received standard dose radiation. For the this analysis, information regarding field size and baseline pulmonary function was not available. Results: Age, sex, stage distribution, and the percentage of patients with a KPS ≥90 were similar among the patients treated on these four studies. Patients receiving hyperfractionated radiotherapy to doses ≥ 72 Gy experienced a higher incidence of radiation pneumonitis ≥ Grade 2, than patients treated with standard doses < 72

  5. Applying radiation approaches to the control of public risks from chemical agents

    International Nuclear Information System (INIS)

    IF a hazardous agent has a threshold, prevention is the obvious measure of success. To the eyes of this author, success is also achieveable for a hazardous agent that may have no threshold and that causes its effects in a probabilistic manner. First, the technical people responsible for protection must be given a reasonable, well defined risk objective by governmental authorities. To the extent that they meet that objective (1) without unnecessarily increasing operational costs, (2) without interfering unnecessarily with operational activities, and (3) without diverting resources away from greater risks, they are successful. Considering these three qualifications, radiation protection for members of the public can hardly be presented as the panacea for other hazardous agents. It would be an error to dismiss the improvement opportunities discussed above as being of acdemic interest only. Decades of experience with radiation have demonstrated that these problems are both real adn significant. In the US the axioms discussed above are accepted as scientific fact for radiation by many policy makers, the news media and the public. For any operation the collective dose is calculated using zero dose as the lower limit of integration, the results are converted to cancer deaths using the risk coefficients, and decisions are made as though these deaths would actually occur without governmental intervention. As a result, billions of dollars and a very large number of highly skilled persons are being expended to protect against radiation doses far smaller than geographical variations in the natural radiation background. These expenditures are demanded by, and required for well-meaning, nontechnical people who have been misled. It is often stated by knowledgeable people that if the degree of protection required for radiation were also to be requested for the other hazards, human progress would come to a halt. If the radiation approaches are to be used in the control of public

  6. Breast cancer risk among Swedish hemangioma patients and possible consequences of radiation-induced genomic instability

    Energy Technology Data Exchange (ETDEWEB)

    Eidemueller, Markus, E-mail: markus.eidemueller@helmholtz-muenchen.de [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, 85764 Neuherberg (Germany); Holmberg, Erik [Department of Oncology, Sahlgrenska University Hospital, SE-413 45 Goeteborg (Sweden); Jacob, Peter [Helmholtz Zentrum Muenchen, Institute of Radiation Protection, 85764 Neuherberg (Germany); Lundell, Marie [Department of Medical Physics, Radiumhemmet, Karolinska University Hospital, SE-171 76 Stockholm (Sweden); Karlsson, Per [Department of Oncology, Sahlgrenska University Hospital, SE-413 45 Goeteborg (Sweden)

    2009-10-02

    Breast cancer incidence among 17,158 female Swedish hemangioma patients was analyzed with empirical excess relative risk models and with a biologically-based model of carcinogenesis. The patients were treated in infancy mainly by external application of radium-226. The mean and median absorbed doses to the breast were 0.29 and 0.04 Gy, and a total of 678 breast cancer cases have been observed. Both models agree very well in the risk estimates with an excess relative risk and excess absolute risk at the age of 50 years, about the mean age of breast cancer incidence, of 0.25 Gy{sup -1}(95% CI 0.14; 0.37) and 30.7 (10{sup 5}BYRGy){sup -1} (95% CI 16.9; 42.8), respectively. Models incorporating effects of radiation-induced genomic instability were developed and applied to the hemangioma cohort. The biologically-based description of the radiation risk was significantly improved with a model of genomic instability at an early stage of carcinogenesis.

  7. Long-term risk of secondary skin cancers after radiation therapy for Hodgkin’s lymphoma

    International Nuclear Information System (INIS)

    Purpose: Survivors of Hodgkin’s lymphoma (HL) are at risk of secondary tumors. We investigated the risk of secondary skin cancers after radiotherapy compared to treatment without radiation and to an age-matched population. Material and methods: