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Sample records for low-dose-rate radiation exposures

  1. Injury of the blood-testies barrier after low-dose-rate chronic radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Young Hoon; Bae Min Ji; Lee, Chang Geun; Yang, Kwang Mo; Jur, Kyu; Kim, Jong Sun [Dongnam Institute of Radiological and Medical Science, Busan (Korea, Republic of)

    2014-04-15

    The systemic effect of radiation increases in proportionally with the dose and dose rate. Little is known concerning the relationships between harmful effects and accumulated dose, which is derived from continuous low-dose rate radiation exposure. Recent our studies show that low-dose-rate chronic radiation exposure (3.49 mGy/h) causes adverse effects in the testis at a dose of 2 Gy (6 mGy/h). However, the mechanism of the low-dose-rate 2 Gy irradiation induced testicular injury remains unclear. The present results indicate that low-dose rate chronic radiation might affect the BTB permeability, possibly by decreasing levels of ZO-1, Occludin-1, and NPC-2. Furthermore, our results suggest that there is a risk of male infertility through BTB impairment even with low-dose-rate radiation if exposure is continuous.

  2. Radiation Leukemogenesis at Low Dose Rates

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    Weil, Michael; Ullrich, Robert

    2013-09-25

    The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an 'inverse dose rate effect' for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

  3. Biological effects of long-term exposure to low dose-rate radiation -- Comparisons of WAM model and LQ model

    CERN Document Server

    Wada, Takahiro; Nakamura, Issei; Tsunoyama, Yuichi; Nakajima, Hiroo; Bando, Masako

    2015-01-01

    Newly proposed Whack-A-Mole (WAM) model which is to be used to estimate the biological effects of artificial radiations is compared with conventionally used Linear-Quadratic model. Basic properties of WAM model are discussed emphasizing on the dose-rate dependence. By adopting the parameters that are determined to fit the mega mouse experiments, biological effects of long-term exposure to extremely low dose-rate radiation are discussed. In WAM model, the effects of the long-term exposure show a saturation property, which makes a clear distinction from the LNT hypothesis which predicts a linear increase of the effects with time.

  4. Fukushima simulation experiment: assessing the effects of chronic low-dose-rate internal 137Cs radiation exposure on litter size, sex ratio, and biokinetics in mice

    Science.gov (United States)

    Nakajima, Hiroo; Yamaguchi, Yoshiaki; Yoshimura, Takashi; Fukumoto, Manabu; Todo, Takeshi

    2015-01-01

    To investigate the transgenerational effects of chronic low-dose-rate internal radiation exposure after the Fukushima Daiichi Nuclear Power Plant accident in Japan, 18 generations of mice were maintained in a radioisotope facility, with free access to drinking water containing 137CsCl (0 and 100 Bq/ml). The 137Cs distribution in the organs of the mice was measured after long-term ad libitum intake of the 137CsCl water. The litter size and the sex ratio of the group ingesting the 137Cs water were compared with those of the control group, for all 18 generations of mice. No significant difference was noted in the litter size or the sex ratio between the mice in the control group and those in the group ingesting the 137Cs water. The fixed internal exposure doses were ∼160 Bq/g and 80 Bq/g in the muscles and other organs, respectively. PMID:26825299

  5. Chronic Low Dose Rate Ionizing Radiation Exposure Induces Premature Senescence in Human Fibroblasts that Correlates with Up Regulation of Proteins Involved in Protection against Oxidative Stress

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    Olga Loseva

    2014-07-01

    Full Text Available The risks of non-cancerous diseases associated with exposure to low doses of radiation are at present not validated by epidemiological data, and pose a great challenge to the scientific community of radiation protection research. Here, we show that premature senescence is induced in human fibroblasts when exposed to chronic low dose rate (LDR exposure (5 or 15 mGy/h of gamma rays from a 137Cs source. Using a proteomic approach we determined differentially expressed proteins in cells after chronic LDR radiation compared to control cells. We identified numerous proteins involved in protection against oxidative stress, suggesting that these pathways protect against premature senescence. In order to further study the role of oxidative stress for radiation induced premature senescence, we also used human fibroblasts, isolated from a patient with a congenital deficiency in glutathione synthetase (GS. We found that these GS deficient cells entered premature senescence after a significantly shorter time of chronic LDR exposure as compared to the GS proficient cells. In conclusion, we show that chronic LDR exposure induces premature senescence in human fibroblasts, and propose that a stress induced increase in reactive oxygen species (ROS is mechanistically involved.

  6. γ-H2AX responds to DNA damage induced by long-term exposure to combined low-dose-rate neutron and γ-ray radiation.

    Science.gov (United States)

    Zhang, Junlin; He, Ying; Shen, Xianrong; Jiang, Dingwen; Wang, Qingrong; Liu, Qiong; Fang, Wen

    2016-01-01

    Risk estimates for low-dose radiation (LDR) remain controversial. The possible involvement of DNA repair-related genes in long-term low-dose-rate neutron-gamma radiation exposure is poorly understood. In this study, 60 rats were divided into control groups and irradiated groups, which were exposed to low-dose-rate n-γ combined radiation (LDCR) for 15, 30, or 60 days. The effects of different cumulative radiation doses on peripheral blood cell (PBC), subsets of T cells of peripheral blood lymphocytes (PBL) and DNA damage repair were investigated. Real-time PCR and immunoblot analyses were used to detect expression of DNA DSB-repair-related genes involved in the NHEJ pathway, such as Ku70 and Ku80, in PBL. The mRNA level of H2AX and the expression level of γ-H2AX were detected by real-time PCR, immunoblot, and flow cytometry. White blood cells (WBC) and platelets (PLT) of all ionizing radiation (IR) groups decreased significantly, while no difference was seen between the 30 day and 60 day exposure groups. The numbers of CD3(+), CD4(+) T cells and CD4(+)/CD8(+) in the PBL of IR groups were lower than in the control group. In the 30 day and 60 day exposure groups, CD8(+) T cells decreased significantly. Real-time PCR and immunoblot results showed no significant difference in the mRNA and protein expression of Ku70 and Ku80 between the control groups and IR groups. However, the mRNA of H2AX increased significantly, and there was a positive correlation with dose. There was no difference in the protein expression of γ-H2AX between 30 day and 60 day groups, which may help to explain the damage to PBL. In conclusion, PBL damage increased with cumulative dose, suggesting that γ-H2AX, but neither Ku70 nor Ku80, plays an important role in PBL impairment induced by LDCR. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Radiation Risk from Chronic Low Dose-Rate Radiation Exposures: The Role of Life-Time Animal Studies - Workshop October 2005

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    Gayle Woloschak

    2009-12-16

    As a part of Radiation research conference, a workshop was held on life-long exposure studies conducted in the course of irradiation experiements done at Argonne National Laboratory between 1952-1992. A recent review article documents many of the issues discussed at that workshop.

  8. Toxicity bioassay in mice exposed to low dose-rate radiation

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    Kim, Joog Sun; Gong, Eun Ji; Heo, Kyu; Yang, Kwang Mo [Research Center, Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of)

    2013-04-15

    The systemic effect of radiation increases in proportion to the dose amount and rate. The association between accumulated radiation dose and adverse effects, which is derived according to continuous low dose-rate radiation exposure, is not clearly elucidated. Our previous study showed that low dose-rate radiation exposure did not cause adverse effects in BALB/c mice at dose levels of ≤2 Gy, but the testis weight decreased at a dose of 2 Gy. In this study, we studied the effects of irradiation at the low dose rate (3.49 mGy/h) in the testes of C57BL/6 mice. Mice exposed to a total dose of 0.02, 0.2, and 2 Gy were found to be healthy and did not show any significant changes in body weight and peripheral blood components. However, mice irradiated with a dose of 2 Gy had significantly decreased testis weight. Further, histological studies and sperm evaluation also demonstrated changes consistent with the findings of decreased testis weight. In fertile patients found to have arrest of sperm maturation, the seminiferous tubules lack the DNMT1 and HDAC1 protein. The decrease of DNMT1 and HDAC1 in irradiated testis may be the part of the mechanism via which low dose-rate irradiation results in teticular injury. In conclusion, despite a low dose-rate radiation, our study found that when mice testis were irradiated with 2 Gy at 3.49 mGy/h dose rate, there was significant testicular and sperm damage with decreased DNMT1 and HDAC1 expression.

  9. Multi-Level Effects of Low Dose Rate Ionizing Radiation on Southern Toad, Anaxyrus [Bufo] terrestris.

    Directory of Open Access Journals (Sweden)

    Karolina Stark

    Full Text Available Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris during its pre-terrestrial stages of development -embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later, to four low dose rates of 137Cs at 0.13, 2.4, 21, and 222 mGy d-1, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay in red blood cells at a dose rate of 21 mGy d-1 and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.

  10. Chronic low-dose-rate ionising radiation affects the hippocampal phosphoproteome in the ApoE−/− Alzheimer mouse model

    DEFF Research Database (Denmark)

    Kempf, Stefan; Janik, Dirk; Barjaktarovic, Zarko

    2017-01-01

    Accruing data indicate that radiation-induced consequences resemble pathologies of neurodegenerative diseases such as Alzheimer´s. The aim of this study was to elucidate the effect on hippocampus of chronic low-dose-rate radiation exposure (1 mGy/day or 20 mGy/day) given over 300 days with cumula...

  11. Low-dose or low-dose-rate ionizing radiation-induced bioeffects in animal models.

    Science.gov (United States)

    Tang, Feng Ru; Loke, Weng Keong; Khoo, Boo Cheong

    2017-03-01

    Animal experimental studies indicate that acute or chronic low-dose ionizing radiation (LDIR) (≤100 mSv) or low-dose-rate ionizing radiation (LDRIR) (radiation exposure (i.e. acute, fractionated or chronic radiation exposure), type of radiation, combination of radiation with other toxic agents (such as smoking, pesticides or other chemical toxins) or animal experimental designs. In this review paper, we aimed to update radiation researchers and radiologists on the current progress achieved in understanding the LDIR/LDRIR-induced bionegative and biopositive effects reported in the various animal models. The roles played by a variety of molecules that are implicated in LDIR/LDRIR-induced health effects will be elaborated. The review will help in future investigations of LDIR/LDRIR-induced health effects by providing clues for designing improved animal research models in order to clarify the current controversial/contradictory findings from existing studies. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  12. Gamma radiation at a human relevant low dose rate is genotoxic in mice

    Science.gov (United States)

    Graupner, Anne; Eide, Dag M.; Instanes, Christine; Andersen, Jill M.; Brede, Dag A.; Dertinger, Stephen D.; Lind, Ole C.; Brandt-Kjelsen, Anicke; Bjerke, Hans; Salbu, Brit; Oughton, Deborah; Brunborg, Gunnar; Olsen, Ann K.

    2016-09-01

    Even today, 70 years after Hiroshima and accidents like in Chernobyl and Fukushima, we still have limited knowledge about the health effects of low dose rate (LDR) radiation. Despite their human relevance after occupational and accidental exposure, only few animal studies on the genotoxic effects of chronic LDR radiation have been performed. Selenium (Se) is involved in oxidative stress defence, protecting DNA and other biomolecules from reactive oxygen species (ROS). It is hypothesised that Se deficiency, as it occurs in several parts of the world, may aggravate harmful effects of ROS-inducing stressors such as ionising radiation. We performed a study in the newly established LDR-facility Figaro on the combined effects of Se deprivation and LDR γ exposure in DNA repair knockout mice (Ogg1-/-) and control animals (Ogg1+/-). Genotoxic effects were seen after continuous radiation (1.4 mGy/h) for 45 days. Chromosomal damage (micronucleus), phenotypic mutations (Pig-a gene mutation of RBCCD24-) and DNA lesions (single strand breaks/alkali labile sites) were significantly increased in blood cells of irradiated animals, covering three types of genotoxic activity. This study demonstrates that chronic LDR γ radiation is genotoxic in an exposure scenario realistic for humans, supporting the hypothesis that even LDR γ radiation may induce cancer.

  13. Chronic low-dose-rate ionising radiation affects the hippocampal phosphoproteome in the ApoE-/- Alzheimer's mouse model

    DEFF Research Database (Denmark)

    Kempf, S. J.; Janik, Dirk; Barjaktarovic, Zarko

    2016-01-01

    Accruing data indicate that radiation-induced consequences resemble pathologies of neurodegenerative diseases such as Alzheimer's. The aim of this study was to elucidate the effect on hippocampus of chronic low-dose-rate radiation exposure (1 mGy/day or 20 mGy/day) given over 300 days...... that several molecular targets induced by chronic low-dose-rate radiation overlap with those of Alzheimer's pathology. It may suggest that ionising radiation functions as a contributing risk factor to this neurodegenerative disease....... with cumulative doses of 0.3 Gy and 6.0 Gy, respectively. ApoE deficient mutant C57Bl/6 mouse was used as an Alzheimer's model. Using mass spectrometry, a marked alteration in the phosphoproteome was found at both dose rates. The radiation-induced changes in the phosphoproteome were associated with the control...

  14. The effect of low dose rate on metabolomic response to radiation in mice

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    Goudarzi, Maryam [Georgetown University, Biochemistry and Molecular and Cellular Biology, Washington, DC (United States); Mak, Tytus D. [Georgetown University, Lombardi Comprehensive Cancer Center, Washington, DC (United States); Chen, Congju; Smilenov, Lubomir B.; Brenner, David J. [Columbia University, Center for High-Throughput Minimally-Invasive Radiation Biodosimetry, New York, NY (United States); Fornace, Albert J. [Georgetown University, Biochemistry and Molecular and Cellular Biology, Washington, DC (United States); Georgetown University, Lombardi Comprehensive Cancer Center, Washington, DC (United States)

    2014-11-15

    Metabolomics has been shown to have utility in assessing responses to exposure by ionizing radiation (IR) in easily accessible biofluids such as urine. Most studies to date from our laboratory and others have employed γ-irradiation at relatively high dose rates (HDR), but many environmental exposure scenarios will probably be at relatively low dose rates (LDR). There are well-documented differences in the biologic responses to LDR compared to HDR, so an important question is to assess LDR effects at the metabolomics level. Our study took advantage of a modern mass spectrometry approach in exploring the effects of dose rate on the urinary excretion levels of metabolites 2 days after IR in mice. A wide variety of statistical tools were employed to further focus on metabolites, which showed responses to LDR IR exposure (0.00309 Gy/min) distinguishable from those of HDR. From a total of 709 detected spectral features, more than 100 were determined to be statistically significant when comparing urine from mice irradiated with 1.1 or 4.45 Gy to that of sham-irradiated mice 2 days post-exposure. The results of this study show that LDR and HDR exposures perturb many of the same pathways such as TCA cycle and fatty acid metabolism, which also have been implicated in our previous IR studies. However, it is important to note that dose rate did affect the levels of particular metabolites. Differences in urinary excretion levels of such metabolites could potentially be used to assess an individual's exposure in a radiobiological event and thus would have utility for both triage and injury assessment. (orig.)

  15. PRE-EXPOSURE OF MICE TO LOW DOSE OR LOW DOSE RATE IONIZING RADIATION REDUCES CHROMOSOME ABERRATIONS INDUCED BY SUBSEQUENT EXPOSURE TO HIGH DOSE OF RADIATION OR MITOMYCIN C

    Institute of Scientific and Technical Information of China (English)

    于文儒; 王明东; 蔡露; 金玉珂

    1995-01-01

    The phenomenon of cytogenetic adaptive and cross-adaptive response induced by low dose irradiation and chemical mutagen in mice is described. We found, firstly, that adapration can be induced by acute low dose X-irracliation (0—100 mGy). Secondly, a cross-adaptation can occur between X-irradiatlon and rrdto-mycin C (MMC). And finally, mice pre-exposed to chronic low dose rate 60Co-Gamma irradiation (0-226. 0 mGy/day) are less susceptible to chromosome aberration induced by subsequent acute higher X-irradiation. Therefore, our data suggest that radioadaptlve respotrse depends on dose, dose rate and time interval. Possible mechanisms are also discussed.

  16. Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures

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    Scott, Bobby, R., Ph.D.

    2003-06-27

    applications of NEOTRANS2, indicate that nonlinear threshold-type, dose-response relationships for excess stochastic effects (problematic nonlethal mutations, neoplastic transformation) should be expected after exposure to low linear energy transfer (LET) gamma rays or gamma rays in combination with high-LET alpha radiation. Similar thresholds are expected for low-dose-rate low-LET beta irradiation. We attribute the thresholds to low-dose, low-LET radiation induced protection against spontaneous mutations and neoplastic transformations. The protection is presumed mainly to involve selective elimination of problematic cells via apoptosis. Low-dose, low-LET radiation is presumed to trigger wide-area cell signaling, which in turn leads to problematic bystander cells (e.g., mutants, neoplastically transformed cells) selectively undergoing apoptosis. Thus, this protective bystander effect leads to selective elimination of problematic cells (a tissue cleansing process in vivo). However, this protective bystander effects is a different process from low-dose stimulation of the immune system. Low-dose, low-LET radiation stimulation of the immune system may explain why thresholds for inducing excess cancer appear much larger (possibly more than 100-fold larger) than thresholds for inducing excess mutations and neoplastic transformations, when the dose rate is low. For ionizing radiation, the current risk assessment paradigm is such that the relative risk (RR) is always ¡Ý 1, no matter how small the dose. Our research results indicate that for low-dose or low-dose-rate, low-LET irradiation, RR < 1 may be more the rule than the exception. Directly tied to the current RR paradigm are the billion-dollar cleanup costs for radionuclide-contaminated DOE sites. Our research results suggest that continued use of the current RR paradigm for which RR ¡Ý 1 could cause more harm than benefit to society (e.g., by spreading unwarranted fear about phantom excess risks associated with low-dose low

  17. Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Bobby, R., Ph.D.

    2003-06-27

    applications of NEOTRANS2, indicate that nonlinear threshold-type, dose-response relationships for excess stochastic effects (problematic nonlethal mutations, neoplastic transformation) should be expected after exposure to low linear energy transfer (LET) gamma rays or gamma rays in combination with high-LET alpha radiation. Similar thresholds are expected for low-dose-rate low-LET beta irradiation. We attribute the thresholds to low-dose, low-LET radiation induced protection against spontaneous mutations and neoplastic transformations. The protection is presumed mainly to involve selective elimination of problematic cells via apoptosis. Low-dose, low-LET radiation is presumed to trigger wide-area cell signaling, which in turn leads to problematic bystander cells (e.g., mutants, neoplastically transformed cells) selectively undergoing apoptosis. Thus, this protective bystander effect leads to selective elimination of problematic cells (a tissue cleansing process in vivo). However, this protective bystander effects is a different process from low-dose stimulation of the immune system. Low-dose, low-LET radiation stimulation of the immune system may explain why thresholds for inducing excess cancer appear much larger (possibly more than 100-fold larger) than thresholds for inducing excess mutations and neoplastic transformations, when the dose rate is low. For ionizing radiation, the current risk assessment paradigm is such that the relative risk (RR) is always ¡Ý 1, no matter how small the dose. Our research results indicate that for low-dose or low-dose-rate, low-LET irradiation, RR < 1 may be more the rule than the exception. Directly tied to the current RR paradigm are the billion-dollar cleanup costs for radionuclide-contaminated DOE sites. Our research results suggest that continued use of the current RR paradigm for which RR ¡Ý 1 could cause more harm than benefit to society (e.g., by spreading unwarranted fear about phantom excess risks associated with low-dose low

  18. Chloroquine Improves Survival and Hematopoietic Recovery After Lethal Low-Dose-Rate Radiation

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    Lim Yiting [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hedayati, Mohammad; Merchant, Akil A.; Zhang Yonggang; Yu, Hsiang-Hsuan M. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Kastan, Michael B. [Department of Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina (United States); Matsui, William, E-mail: matsuwi@jhmi.edu [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); DeWeese, Theodore L., E-mail: deweete@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)

    2012-11-01

    Purpose: We have previously shown that the antimalarial agent chloroquine can abrogate the lethal cellular effects of low-dose-rate (LDR) radiation in vitro, most likely by activating the ataxia-telangiectasia mutated (ATM) protein. Here, we demonstrate that chloroquine treatment also protects against lethal doses of LDR radiation in vivo. Methods and Materials: C57BL/6 mice were irradiated with a total of 12.8 Gy delivered at 9.4 cGy/hour. ATM null mice from the same background were used to determine the influence of ATM. Chloroquine was administered by two intraperitoneal injections of 59.4 {mu}g per 17 g of body weight, 24 hours and 4 hours before irradiation. Bone marrow cells isolated from tibia, fibula, and vertebral bones were transplanted into lethally irradiated CD45 congenic recipient mice by retroorbital injection. Chimerism was assessed by flow cytometry. In vitro methylcellulose colony-forming assay of whole bone marrow cells and fluorescence activated cell sorting analysis of lineage depleted cells were used to assess the effect of chloroquine on progenitor cells. Results: Mice pretreated with chloroquine before radiation exhibited a significantly higher survival rate than did mice treated with radiation alone (80% vs. 31%, p = 0.0026). Chloroquine administration before radiation did not affect the survival of ATM null mice (p = 0.86). Chloroquine also had a significant effect on the early engraftment of bone marrow cells from the irradiated donor mice 6 weeks after transplantation (4.2% vs. 0.4%, p = 0.015). Conclusion: Chloroquine administration before radiation had a significant effect on the survival of normal but not ATM null mice, strongly suggesting that the in vivo effect, like the in vitro effect, is also ATM dependent. Chloroquine improved the early engraftment of bone marrow cells from LDR-irradiated mice, presumably by protecting the progenitor cells from radiation injury. Chloroquine thus could serve as a very useful drug for protection

  19. Risk of solid cancer in low dose-rate radiation epidemiological studies and the dose-rate effectiveness factor.

    Science.gov (United States)

    Shore, Roy; Walsh, Linda; Azizova, Tamara; Rühm, Werner

    2017-10-01

    Estimated radiation risks used for radiation protection purposes have been based primarily on the Life Span Study (LSS) of atomic bomb survivors who received brief exposures at high dose rates, many with high doses. Information is needed regarding radiation risks from low dose-rate (LDR) exposures to low linear-energy-transfer (low-LET) radiation. We conducted a meta-analysis of LDR epidemiologic studies that provide dose-response estimates of total solid cancer risk in adulthood in comparison to corresponding LSS risks, in order to estimate a dose rate effectiveness factor (DREF). We identified 22 LDR studies with dose-response risk estimates for solid cancer after minimizing information overlap. For each study, a parallel risk estimate was derived from the LSS risk model using matching values for sex, mean ages at first exposure and attained age, targeted cancer types, and accounting for type of dosimetric assessment. For each LDR study, a ratio of the excess relative risk per Gy (ERR Gy(-1)) to the matching LSS ERR risk estimate (LDR/LSS) was calculated, and a meta-analysis of the risk ratios was conducted. The reciprocal of the resultant risk ratio provided an estimate of the DREF. The meta-analysis showed a LDR/LSS risk ratio of 0.36 (95% confidence interval [CI] 0.14, 0.57) for the 19 studies of solid cancer mortality and 0.33 (95% CI 0.13, 0.54) when three cohorts with only incidence data also were added, implying a DREF with values around 3, but statistically compatible with 2. However, the analyses were highly dominated by the Mayak worker study. When the Mayak study was excluded the LDR/LSS risk ratios increased: 1.12 (95% CI 0.40, 1.84) for mortality and 0.54 (95% CI 0.09, 0.99) for mortality + incidence, implying a lower DREF in the range of 1-2. Meta-analyses that included only cohorts in which the mean dose was radiation exposure. The LDR data provide direct evidence regarding risk from exposures at low dose rates as an important complement to the

  20. Characteristics of changes in the number of yH2AX and Rad51 protein foci in human skin fibroblasts after prolonged exposure to low-dose rate X-ray radiation

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    Ozerov I.V.

    2014-12-01

    Full Text Available Aim: to compare the repair process of DNA double-strand breaks in mammalian cells after acute versus prolonged exposure to X-ray irradiation with different dose rates. Material and methods. Studies were performed on primary human fibroblasts isolated from skin biopsies of healthy volunteers (women, 29 and 30 years. Cells were irradiated using an X-ray machine RUB RUST-M1 (JSC "Ruselectronics", Moscow, Russia at 37°C temperature with a dose rate of 400 mGy/min (200 kV, 2*2.4 mA, a filter of 1.5mm AI or 4 mGy/min (50 kV, 2*0.4 mA, a filter of 1.5 mm AI. Immuno-cytochemical protein staining was utilized for yH2AX and Rad51 foci analysis. Results. Phosphorylated histone H2AX (yH2AX and the key protein of homologous recombination Rad51 foci formation and disappearance kinetics were investigated simultaneously in primary human dermal fibroblasts after acute and prolonged exposure to X-ray radiation at a same dose. It was shown that the relative yield of yH2AX foci per dose reduces with decrease in dose rate, while the relative yield of Rad51 foci conversely increases. Conclusion. Our findings suggest the fundamental differences in the ratio of non-homologous end joining and homologous recombination DNA repair in acute versus prolonged irradiated cells.

  1. Genetic Factors Affecting Susceptibility to Low Dose & Low Dose-Rate Radiation

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    Bedford, Joel

    2014-04-18

    Our laboratory has, among other things, developed and used the gamma H2AX focus assay and other chromosomal and cell killing assays to show that differences in this DNA double strand break (dsb) related response can be clearly and distinctly demonstrated for cells which are mildly hyper-radiosensitive such as those associated with A-T heterozygosity. We have found this level of mild hypersensitivity for cells from some 20 to 30 % of apparently normal individuals and from apparently normal parents of Retinoblastoma patients. We found significant differences in gene expression in somatic cells from unaffected parents of Rb patients as compared with normal controls, suggesting that these parents may harbor some as yet unidentified genetic abnormality. In other experiments we sought to determine the extent of differences in normal human cellular reaponses to radiation depending on their irradiation in 2D monolayer vs 3D organized acinar growth conditions. We exmined cell reproductive death, chromosomal aberration induction, and the levels of γ-H2AX foci in cells after single acute gamma-ray doses and immediately after 20 hours of irradiation at a dose rate of 0.0017 Gy/min. We found no significant differences in the dose-responses of these cells under the 2D or 3D growth conditions. While this does not mean such differences cannot occur in other situations, it does mean that they do not generally or necessarily occur. In another series of studies in collaboration with Dr Chuan Li, with supprt from this current grant. We reported a role for apoptotic cell death in promoting wound healing and tissue regeneration in mice. Apoptotic cells released growth signals that stimulated the proliferation of progenitor or stem cells. In yet another collaboration with Dr, B. Chen with funds from this grant, the relative radiosensitivity to cell killing as well as chromosomal instability of 13 DNA-PKcs site-directed mutant cell lines (defective at phosphorylation sites or kinase

  2. Enhancement of viability of radiosensitive (PBMC) and resistant (MDA-MB-231) clones in low-dose-rate cobalt-60 radiation therapy

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    Falcao, Patricia Lima, E-mail: patricialfalcao@gmail.com [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil); Motta, Barbara Miranda; Lima, Fernanda Castro de; Lima, Celso Vieira; Campos, Tarcisio Passos Ribeiro [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2015-05-15

    Objective: in the present study, the authors investigated the in vitro behavior of radio-resistant breast adenocarcinoma (MDA-MB-231) cells line and radiosensitive peripheral blood mononuclear cells (PBMC), as a function of different radiation doses, dose rates and postirradiation time kinetics, with a view to the interest of clinical radiotherapy. Materials and methods: the cells were irradiated with Co-60, at 2 and 10 Gy and two different exposure rates, 339.56 cGy.min{sup -1} and the other corresponding to one fourth of the standard dose rates, present over a 10-year period of cobalt therapy. Post-irradiation sampling was performed at pre-established kinetics of 24, 48 and 72 hours. The optical density response in viability assay was evaluated and a morphological analysis was performed. Results: radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates. MDAMB-231 cells presented viability decrease only at higher dose and dose rate. The results showed MDA-MB-231 clone expansion at low dose rate after 48-72 hours post-radiation. Conclusion: low dose rate shows a possible potential clinical impact involving decrease in management of radio-resistant and radiosensitive tumor cell lines in cobalt therapy for breast cancer. (author)

  3. Enhancement of viability of radiosensitive (PBMC and resistant (MDA-MB-231 clones in low-dose-rate cobalt-60 radiation therapy

    Directory of Open Access Journals (Sweden)

    Patrícia Lima Falcão

    2015-06-01

    Full Text Available Abstract Objective: In the present study, the authors investigated the in vitro behavior of radio-resistant breast adenocarcinoma (MDA-MB-231 cells line and radiosensitive peripheral blood mononuclear cells (PBMC, as a function of different radiation doses, dose rates and postirradiation time kinetics, with a view to the interest of clinical radiotherapy. Materials and Methods: The cells were irradiated with Co-60, at 2 and 10 Gy and two different exposure rates, 339.56 cGy.min–1 and the other corresponding to one fourth of the standard dose rates, present over a 10-year period of cobalt therapy. Post-irradiation sampling was performed at pre-established kinetics of 24, 48 and 72 hours. The optical density response in viability assay was evaluated and a morphological analysis was performed. Results: Radiosensitive PBMC showed decrease in viability at 2 Gy, and a more significant decrease at 10 Gy for both dose rates. MDAMB- 231 cells presented viability decrease only at higher dose and dose rate. The results showed MDA-MB-231 clone expansion at low dose rate after 48–72 hours post-radiation. Conclusion: Low dose rate shows a possible potential clinical impact involving decrease in management of radio-resistant and radiosensitive tumor cell lines in cobalt therapy for breast cancer.

  4. Low-dose-rate high-let radiation cytogenetic effects on mice in vivo as model of space radiation action on mammalian

    Science.gov (United States)

    Sorokina, Svetlana; Zaichkina, Svetlana; Rozanova, Olga; Aptikaeva, Gella; Romanchenko, Sergei; Smirnova, Helene; Dyukina, Alsu; Peleshko, Vladimir

    At present time little is known concerning the biological effects of low-dose-rate high-LET radiation exposure in space. The currently available experimental data on the biological effect of low doses of chronic radiation with high-LET values, which occur under the conditions of aircraft and space flights, have been primarily obtained in the examinations of pilots and astronauts after flights. Another way of obtaining this kind of evidence is the simulation of irradiation conditions during aircraft and space flights on high-energy accelerators and the conduction of large-scale experiments on animals under these conditions on Earth. In the present work, we investigated the cytogenetic effects of low-dose-rate high-LET radiation in the dose ranges of 0.2-30 cGy (1 cGy/day) and 0.5-16 cGy (0.43 cGy/day) in the radiation field behind the concrete shield of the Serpukhov accelerator of 70 GeV protons that simulates the spectral and component composition of radiation fields formed in the conditions of high-altitude flights on SHK mice in vivo. The dose dependence, adaptive response (AR) and the growth of solid tumor were examined. For induction of AR, two groups of mice were exposed to adapting doses of 0.2-30 cGy and the doses of 0.5-16 cGy of high-LET radiation. For comparison, third group of mice from unirradiated males was chronically irradiated with X-rays at adapting doses of 10 cGy (1 cGy/day). After a day, the mice of all groups were exposed to a challenging dose of 1.5 Gy of X-rays (1 Gy/min). After 28 h, the animals of all groups were killed by the method of cervical dislocation. Bone marrow specimens for calculating micronuclei (MN) in polychromatic erythrocytes (PCE) were prepared by a conventional method with minor modifications. The influence of adapting dose of 16 cGy on the growth of solid tumor of Ehrlich ascite carcinoma was estimated by measuring the size of the tumor at different times after the inoculation of ascitic cells s.c. into the femur. It was

  5. Macroarray analysis of gene expression in hematopoietic tissues from mice continuously irradiated by low dose-rate ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Saitou, Mikio; Nakamura, Shingo; Shirata, Katsutoshi; Yanai, Takanori; Izumi, Jun; Sugihara, Takashi; Tanaka, Satoshi; Tanaka, Kimio; Otsu, Hiroshi; Sato, Fumiaki [Inst. for Environmental Sciences, Rokkasho, Aomori (Japan)

    2002-07-01

    We found that the number of hematopoietic progenitor cells in bone marrow and spleen from 4 - 8 Gy-irradiated mice decreased about 50%, in spite of no change in the number of peripheral blood cells. To evaluate the effects of chronic irradiation by low dose-rate ionizing radiation on the gene expression in mice hematopoietic cells from bone marrow and spleen, the RNA expressions of more than 500 genes such as cytokine genes and oncogenes were measured on the membranes by the RNA macroarray analysis method at accumulated doses at 4.7 and 8 Gy in specific-pathogen-free (SPF) C3H/HeN female mice irradiated by {sup 137}Cs {gamma}-rays with the dose rate of 20 mGy/day. The RNA macroarray analysis in spleens from 8 Gy-irradiated mice showed that the expressions in 16 genes including noggin were more than 1.5 times larger than that of control, while those in 64 genes including shh (sonic hedgehog) and BMP-4 (bone morphogenesis protein 4) were more than 1.5 times smaller than that of control. (author)

  6. Low doses effects and gamma radiations low dose rates; Les effets des faibles doses et des faibles debits de doses de rayons gamma

    Energy Technology Data Exchange (ETDEWEB)

    Averbeck, D. [Institut Curie, CNRS UMR 2027, 75 - Paris (France)

    1999-07-01

    This expose wishes for bringing some definitions and base facts relative to the problematics of low doses effects and low dose rates effects. It shows some already used methods and some actual experimental approaches by focusing on the effects of ionizing radiations with a low linear energy transfer. (N.C.)

  7. [Searching Radiation Countermeasures using the Model of Prolonged Irradiation of Mice with Low Dose Rate and Evaluation of Their Influence on Heat Shock Protein Genes Expression].

    Science.gov (United States)

    Rozhdestvensky, L M; Mikhailov, V F; Schlyakova, T G; Shagirova, J M; Shchegoleva, R A; Raeva, N F; Lisina, N I; Shulenina, L V; Zorin, V V; Pchelka, A V; Trubitsina, K Y

    2015-01-01

    Different radiomodificators (cytokine betaleukine, antioxidant phenoxan, antigipoksant limontar and nucleoside riboxin) were investigated on mice for evaluating their radiation protective capacity against prolonged (21 h) exposure at a dose of 12.6 Gy at a low dose rate of 10 mGy/min. Bone marrow cellularity and endogenic CFUs were used as evaluation criteria 9 days after exposure. Simultaneously, expression of the heat shock proteins of 25, 70 and 90 kDa in unexposed mice bone marrow was studied 2, 24 and 48 h after injections. Betaleukine only had a positive significant effect in both tests in the variants of 50 mcg/kg and 3 mcg/kg when administered 2 h and 22 h before exposure, correspondingly. Effects of betaleukine HSPs on expression were both stimulating and inhibiting, that was in contradiction with a constant positive effect in 5 experiments on exposed mice for each betaleukine variant. It argues against the vital role of HSPs in the betaleukine antiradiation effect. In 2 experiments with high temperatures betaleukine administered at a dose of 50 mcg/kg evoked a very high HSP-70 gene expression after 24 h, and mice exposed to irradiation at that time in a parallel experiment showed an increased radiation effect. It corresponds to the idea that HSPs serve a stress indicator.

  8. Evidence That Lifelong Low Dose Rates of Ionizing Radiation Increase Lifespan in Long- and Short-Lived Dogs.

    Science.gov (United States)

    Cuttler, Jerry M; Feinendegen, Ludwig E; Socol, Yehoshua

    2017-01-01

    After the 1956 radiation scare to stop weapons testing, studies focused on cancer induction by low-level radiation. Concern has shifted to protecting "radiation-sensitive individuals." Since longevity is a measure of health impact, this analysis reexamined data to compare the effect of dose rate on the lifespans of short-lived (5% and 10% mortality) dogs and on the lifespans of dogs at 50% mortality. The data came from 2 large-scale studies. One exposed 10 groups to different γ dose rates; the other exposed 8 groups to different lung burdens of plutonium. Reexamination indicated that normalized lifespans increased more for short-lived dogs than for average dogs, when radiation was moderately above background. This was apparent by interpolating between the lifespans of nonirradiated dogs and exposed dogs. The optimum lifespan increase appeared at 50 mGy/y. The threshold for harm (decreased lifespan) was 700 mGy/y for 50% mortality dogs and 1100 mGy/y for short-lived dogs. For inhaled α-emitting particulates, longevity was remarkably increased for short-lived dogs below the threshold for harm. Short-lived dogs seem more radiosensitive than average dogs and they benefit more from low radiation. If dogs model humans, this evidence would support a change to radiation protection policy. Maintaining exposures "as low as reasonably achievable" (ALARA) appears questionable.

  9. Evidence That Lifelong Low Dose Rates of Ionizing Radiation Increase Lifespan in Long- and Short-Lived Dogs

    Science.gov (United States)

    Feinendegen, Ludwig E.; Socol, Yehoshua

    2017-01-01

    After the 1956 radiation scare to stop weapons testing, studies focused on cancer induction by low-level radiation. Concern has shifted to protecting “radiation-sensitive individuals.” Since longevity is a measure of health impact, this analysis reexamined data to compare the effect of dose rate on the lifespans of short-lived (5% and 10% mortality) dogs and on the lifespans of dogs at 50% mortality. The data came from 2 large-scale studies. One exposed 10 groups to different γ dose rates; the other exposed 8 groups to different lung burdens of plutonium. Reexamination indicated that normalized lifespans increased more for short-lived dogs than for average dogs, when radiation was moderately above background. This was apparent by interpolating between the lifespans of nonirradiated dogs and exposed dogs. The optimum lifespan increase appeared at 50 mGy/y. The threshold for harm (decreased lifespan) was 700 mGy/y for 50% mortality dogs and 1100 mGy/y for short-lived dogs. For inhaled α-emitting particulates, longevity was remarkably increased for short-lived dogs below the threshold for harm. Short-lived dogs seem more radiosensitive than average dogs and they benefit more from low radiation. If dogs model humans, this evidence would support a change to radiation protection policy. Maintaining exposures “as low as reasonably achievable” (ALARA) appears questionable.

  10. The Effects of Low Dose-Rate Ionizing Radiation on the Shapes of Transients in the LM124 Operational Amplifier

    Science.gov (United States)

    Buchner, Stephen; McMorrow, Dale; Roche, Nicholas; Dusseau, Laurent; Pease, Ron L.

    2008-01-01

    Shapes of single event transients (SETs) in a linear bipolar circuit (LM124) change with exposure to total ionizing dose (TID) radiation. SETs shape changes are a direct consequence of TID-induced degradation of bipolar transistor gain. A reduction in transistor gain causes a reduction in the drive current of the current sources in the circuit, and it is the lower drive current that most affects the shapes of large amplitude SETs.

  11. PARP inhibition sensitizes to low dose-rate radiation TMPRSS2-ERG fusion gene-expressing and PTEN-deficient prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Payel Chatterjee

    Full Text Available Exposure to genotoxic agents, such as irradiation produces DNA damage, the toxicity of which is augmented when the DNA repair is impaired. Poly (ADP-ribose polymerase (PARP inhibitors were found to be "synthetic lethal" in cells deficient in BRCA1 and BRCA2 that impair homologous recombination. However, since many tumors, including prostate cancer (PCa rarely have on such mutations, there is considerable interest in finding alternative determinants of PARP inhibitor sensitivity. We evaluated the effectiveness of radiation in combination with the PARP inhibitor, rucaparib in PCa cells. The combination index for clonogenic survival following radiation and rucaparib treatments revealed synergistic interactions in a panel of PCa cell lines, being strongest for LNCaP and VCaP cells that express ETS gene fusion proteins. These findings correlated with synergistic interactions for senescence activation, as indicated by β--galactosidase staining. Absence of PTEN and presence of ETS gene fusion thus facilitated activation of senescence, which contributed to decreased clonogenic survival. Increased radiosensitivity in the presence of rucaparib was associated with persistent DNA breaks, as determined by χ-H2AX, p53BP1, and Rad51 foci. VCaP cells, which harbor the TMPRSS2-ERG gene fusion and PC3 cells that stably express a similar construct (fusion III showed enhanced sensitivity towards rucaparib, which, in turn, increased the radiation response to a similar extent as the DNA-PKcs inhibitor NU7441. Rucaparib radiosensitized PCa cells, with a clear benefit of low dose-rate radiation (LDR administered over a longer period of time that caused enhanced DNA damage. LDR mimicking brachytherapy, which is used successfully in the clinic, was most effective when combined with rucaparib by inducing persistent DNA damage and senescence, leading to decreased clonogenic survival. This combination was most effective in the presence of the TMPRSS2-ERG and in the

  12. PARP inhibition sensitizes to low dose-rate radiation TMPRSS2-ERG fusion gene-expressing and PTEN-deficient prostate cancer cells.

    Science.gov (United States)

    Chatterjee, Payel; Choudhary, Gaurav S; Sharma, Arishya; Singh, Kamini; Heston, Warren D; Ciezki, Jay; Klein, Eric A; Almasan, Alexandru

    2013-01-01

    Exposure to genotoxic agents, such as irradiation produces DNA damage, the toxicity of which is augmented when the DNA repair is impaired. Poly (ADP-ribose) polymerase (PARP) inhibitors were found to be "synthetic lethal" in cells deficient in BRCA1 and BRCA2 that impair homologous recombination. However, since many tumors, including prostate cancer (PCa) rarely have on such mutations, there is considerable interest in finding alternative determinants of PARP inhibitor sensitivity. We evaluated the effectiveness of radiation in combination with the PARP inhibitor, rucaparib in PCa cells. The combination index for clonogenic survival following radiation and rucaparib treatments revealed synergistic interactions in a panel of PCa cell lines, being strongest for LNCaP and VCaP cells that express ETS gene fusion proteins. These findings correlated with synergistic interactions for senescence activation, as indicated by β--galactosidase staining. Absence of PTEN and presence of ETS gene fusion thus facilitated activation of senescence, which contributed to decreased clonogenic survival. Increased radiosensitivity in the presence of rucaparib was associated with persistent DNA breaks, as determined by χ-H2AX, p53BP1, and Rad51 foci. VCaP cells, which harbor the TMPRSS2-ERG gene fusion and PC3 cells that stably express a similar construct (fusion III) showed enhanced sensitivity towards rucaparib, which, in turn, increased the radiation response to a similar extent as the DNA-PKcs inhibitor NU7441. Rucaparib radiosensitized PCa cells, with a clear benefit of low dose-rate radiation (LDR) administered over a longer period of time that caused enhanced DNA damage. LDR mimicking brachytherapy, which is used successfully in the clinic, was most effective when combined with rucaparib by inducing persistent DNA damage and senescence, leading to decreased clonogenic survival. This combination was most effective in the presence of the TMPRSS2-ERG and in the absence of PTEN

  13. Evaluation of the detriment associated with exposure at low doses and low dose rates in the radiation protection system; Evaluation du detriment associe a l'exposition aux faibles doses et faibles debits de dose dans le systeme de radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Vaillant, Ludovic; Schneider, Thierry [CEPN, 28, rue de la Redoute, 92260 Fontenay-aux-Roses (France)

    2012-03-15

    Questions about quantifying the radiological risk associated with exposure to ionising radiation have been debated repeatedly for a variety of exposure situations, including, among others, medical irradiation, discharges from nuclear facilities, transportation of radioactive waste, and potential nuclear accidents. This paper aims to shed light on the link between exposure and risk, focusing on the items that constitute the detriment associated with this exposure. The management of the risk associated with it relies on a cautious hypothesis of a linear no-threshold relation between exposure and risk of death or detriment. The International Commission on Radiological Protection (ICRP) published General Recommendations in 1966 that recognised this relation, but did not publish a quantification of the risk until 1977. The Commission introduced the concept of effective dose as a risk indicator that makes it possible to determine dose limits according to the risk associated with them. In 1990, the Commission proposed a revision of the quantification and construction of detriment. New limits, based on risk quantification and, for the first time, risk tolerability, were proposed. The optimisation of radiation protection - keeping radiation exposure as low as reasonably achievable in light of the economic and social context - became the key principle of the radiation protection system. The use of detriment makes it possible to use economic tools to guide the decision process for this optimisation - by assessing the monetary value of human life. This concept, widely used in health economics during the 1980's, has been criticised by many and must be used cautiously. ICRP published the latest quantifications of detriment in 2007. Detriment is thus an indicator that assesses the risk of death associated with exposure to ionising radiation for an average individual. Its construction relies on simplifying assumptions that are needed to implement a robust and effective

  14. Animal Studies of Residual Hematopoietic and Immune System Injury from Low Dose/Low Dose Rate Radiation and Heavy Metals.

    Science.gov (United States)

    1998-09-01

    exposed to background over, LDR radiation causes activation of the DNA repair amounts of electromagnetic (e.g., ionizing) radiation as system, thus...decrease in the subpopulations of rhythm, which formed the basic wave of proliferation, but granulocytes or on a regular increase in the subpopulations also...fission products as other common genotoxic factors present in the environ- ment (e.g., cancerogenic chemicals, toxic metal ions). " Nuclear fuel operators

  15. Molecular biological study-effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors in murine bone marrow cells

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Mikio; Yamada, Yutaka; Nakamura, Shingo [Inst. for Environmental Sciences, Dept. of Radiobiology, Rokkasho, Aomori (JP)] [and others

    2001-07-01

    To evaluate effects of prolonged irradiation by low dose-rate ionizing radiation on the production of growth factors of cells, the gene expression of five cytokines, interleukin-1{alpha} (IL-1{alpha}), IL-6, IL-11 stem cell factor (SCF) and granulocyte-macrophage colony stimulating factor (GM-CSF), of mice was measured at accumulated doses between 1 and 8 Gy, with the dose interval of 1 Gy. Ten specific-pathogen-free (SPF) C3H/HeN female mice (8 w.o.) per experimental group were irradiated with {sup 137}Cs {gamma}-rays with the doses of 5 - 8 Gy at the dose rate of 20 mGy/(22 h-day), and the gene expression of five cytokines (IL-1{alpha}, IL-6, IL-11, SCF and GM-CSF) in bone marrow and two cytokines (IL-6 and GM-CSF) in spleen cells from the mice was measured semiquantitatively by both the reverse transcriptase-polymerase chain reaction (RT-PCR) and TaqMan Real-Time PCR method. (author)

  16. External beam radiation therapy and a low-dose-rate brachytherapy boost without or with androgen deprivation therapy for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Tobin J.; Hutchinson, Sean Z.; Shrinath, Kushagra; Cruz, Alex A.; Figura, Nicholas B.; Nethers, Kevin; Biagioli, Matthew C.; Fernandez, Daniel C.; Heysek, Randy V.; Wilder, Richard B., E-mail: richard.wilder@moffitt.org [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States)

    2014-07-15

    Purpose: To assess outcomes with external beam radiation therapy (EBRT) and a low-dose-rate (LDR) brachytherapy boost without or with androgen deprivation therapy (ADT) for prostate cancer. Materials and Methods: From January 2001 through August 2011, 120 intermediate-risk or high-risk prostate cancer patients were treated with EBRT to a total dose of 4,500 cGy in 25 daily fractions and a palladium-103 LDR brachytherapy boost of 10,000 cGy (n = 90) or an iodine-125 LDR brachytherapy boost of 11,000 cGy (n = 30). ADT, consisting of a gonadotropin-releasing hormone agonist ± an anti-androgen, was administered to 29/92 (32%) intermediate-risk patients for a median duration of 4 months and 26/28 (93%) high-risk patients for a median duration of 28 months. Results: Median follow-up was 5.2 years (range, 1.1-12.8 years). There was no statistically-significant difference in biochemical disease-free survival (bDFS), distant metastasis-free survival (DMFS), or overall survival (OS) without or with ADT. Also, there was no statistically-significant difference in bDFS, DMFS, or OS with a palladium-103 vs. an iodine-125 LDR brachytherapy boost. Conclusions: There was no statistically-significant difference in outcomes with the addition of ADT, though the power of the current study was limited. The Radiation Therapy Oncology Group 0815 and 0924 phase III trials, which have accrual targets of more than 1,500 men, will help to clarify the role ADT in locally-advanced prostate cancer patients treated with EBRT and a brachytherapy boost. Palladium-103 and iodine-125 provide similar bDFS, DMFS, and OS. (author)

  17. [{sup 131}I]Iodoazomycin arabinoside for low-dose-rate isotope radiotherapy: radiolabeling, stability, long-term whole-body clearance and radiation dosimetry estimates in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Piyush [Department of Oncologic Imaging, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); McQuarrie, Steven A. [Department of Oncologic Imaging, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Zhou, Aihya [Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); McEwan, Alexander J.B. [Department of Oncologic Imaging, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); Wiebe, Leonard I. [Department of Oncologic Imaging, Cross Cancer Institute, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada) and Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada)]. E-mail: leonard.wiebe@ualberta.ca

    2005-08-01

    activities. Based on measured radioactivity burdens during the week following injection and on published animal ([{sup 125}I]IAZA) and clinical ([{sup 123}I]IAZA) dosimetry data, the current dose estimates point to selective tumor irradiation at low dose rates.

  18. Effects of very low dose-rate (90)Sr/(90)Y exposure on the acute moist desquamation response of pig skin.

    Science.gov (United States)

    Millar, W T; Hopewell, J W

    2007-05-01

    Previous data, predominantly involving high dose-rate fractionated irradiation with incomplete repair intervals, had indicated that the kinetics of repair of sublethal damage for acute radiation reactions in pig skin could best be defined by a biphasic repair model with half-times for repair of 0.2 and 5.4 h, partition coefficient 0.5. To further test the validity of this finding and obtain a better estimate of the repair rate of the slow component of repair, the acute response of pig skin to very low dose-rates (VLDR), originally estimated to be 0.0067-0.0244 Gy/min, was investigated as part of a 4 fraction irradiation protocol involving an overall treatment time of VLDR fraction. The total doses administered were originally planned to represent the dose associated with the predicted ED(20), ED(50) and ED(80) (75% of total biological dose given at high dose-rate and 25% at VLDR) calculated on the basis of the repair kinetic parameters obtained from earlier studies. However, during the analysis a revision to the physical dosimetry was identified; this had been overlooked prior to the start of the study. Following completion of irradiation the irradiated sites were examined weekly and the presence or absence of moist desquamation recorded. The incidence of moist desquamation was slightly higher than expected on the basis of the parameters used to calculate iso-effective doses, at least in part as a consequence of the change to the dosimetry. Using likelihood methods and the original dose estimates, the best model based estimate of the dose-rate correction factor for the LDR and VLDR plaques was 1.29. This was comparable with the physical calibration factor, median value 1.23. The VLDR fraction associated with a 50% incidence of moist desquamation, based on experimental observation, was 23.2+/-0.84, 27+/-2.6 and 30.1+/-3.2 Gy, for corrected VLDRs of 0.0247, 0.0093 and 0.0068 Gy/min, respectively. A biphasic model, which incorporated a dose-rate correction factor

  19. Relationship of HepG2 cell sensitivity to continuous low dose-rate irradiation with ATM phosphorylation

    Institute of Scientific and Technical Information of China (English)

    Quelin Mei; Jianyong Yang; Duanming Du; Zaizhong Cheng; Pengcheng liu

    2008-01-01

    Objective: To investigate the change of ATM phosphorylation in HepG2 cells and its effect on HepG2 cell survival under a continuous low dose-rate irradiation.Methods: HepG2 cells were exposed to equivalent doses of irradiation delivered at either a continuous low dose-rate (7.76 cGy/h) or a high dose-rate (4500 cGy/h).The ATM phosphorylated proteins and surviving fraction of HepG2 cell after low dose-rate irradiation were compared with that after equivalent doses of high dose-rate irradiation.Results: The phosphorylation of ATM protein was maximal at 0.5 Gy irradiation delivered at either a high dose-rate or a continuous low dose-rate.As the radiation dose increased, the phosphorylation of ATM protein decreased under continuous low dose-rate irradiation.However, the phosphorylation of ATM protein was remained stable under high dose-rate irradiation.When the phosphorylation of ATM protein under continuous low dose-rate irradiation was equal to that under high dose-rate irradiation, there was no significant difference in the surviving fraction of HepG2 cells between two ir-radiation methods (P>0.05).When the phosphorylation of ATM protein significantly decreased after continuous low dose-rate irradiation compared with that after high dose-rate irradiation, increased amounts of cell killing was found in low dose-rate irradiation (P<0.01).Conclusion: Continuous low dose-rate irradiation increases HepG2 cells radiosensitivity compared with high dose-rate irradiation.The increased amounts of cell killing following continuous low dose-rate exposures are associated with reduced ATM phosphorylated protein.

  20. Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, William F.; von Borstel, Robert C.; Brenner,; Redpath, J. Leslie; Erickson, Barbra E.; Brooks,

    2009-11-12

    The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects.

  1. Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium Annual Meeting of the Environmental Mutagen Society: Agenda and Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Veigl, Martina L. [Environmental Mutagen Society (EMS), Reston, VA (United States); Case Western Reserve Univ., Cleveland, OH (United States). Case Comprehensive Cancer Center; Morgan, William F. [Univ. of Maryland, College Park, MD (United States); Schwartz, Jeffrey L. [Univ. of Washington, Seattle, WA (United States)

    2009-11-11

    The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects. This report shows the agenda and abstracts for this symposium.

  2. Study of the radiation levels in low dose rate brachytherapy zones of the National Institute of Neoplastic Illnesses; Estudio de los Niveles de Radiacion en Zonas de Braquiterapia de Baja Tasa de Dosis del Instituto Nacional de Enfermedades Neoplasicas

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa J, N.; Mora Y, B. [Instituto Nacional de Enfermedades Neoplasicas, Lima (Peru)]. e-mail: navorf01@yahoo.es

    2006-07-01

    The present study has as objective to evaluate the radiation levels of the Brachytherapy work areas of low dose rate (Gammateque, nurses station and of hospitalization rooms of patients RIC of 4th, 5th Floor-East) and to estimate the effective dose of the occupationally exposed personnel and the public in general. The measurements of the dose rate in these areas, were registered with a radiations monitor Inspector trademark, during a period of 60 days, without altering the routinary work conditions. The more high levels of environmental dose equivalent rate registered in the different work areas its are of 1.41 and 47.78 {mu}Sv/h rooms 1 and 2 in the Gammateque environments, in the hospitalization rooms of the 4th and 5th floor in the point 1 are of 40.77 and 23.67, {mu}Sv/h respectively and in the point 2 are of 129.19 and 39.93, {mu}Sv/h respectively, and in the nurses station of the 4th and 5th floor its are respectively of 7.62 u Sv/h and 0.45 u Sv/h. According to the carried out measurements and the permanency in the work place is possible to estimate the effective dose involved to the occupationally exposed personnel. The personnel that works in Gammateque could be receiving respectively as maximum dose 0.61 mSv/month, and the personnel that works in the nurses station of 13.17 and 0.78 mSv/year in the 4th and 5th floor. These registered differences among the two floors are due to that the 5th floor counts with the shielding systems (screen) contrary to the 4th, another of the factors is the distribution form of the patient beds RIC. We should have present that the radiation levels although in some cases it is very high, however, they are below of the permissible limits according to standards, but it is still possible to reduce even more, the radiation levels in the critical points fulfilling with the ALARA principle. (Author)

  3. Effects of low-dose rate γ-irradiation combined with simulated microgravity on markers of oxidative stress, DNA methylation potential, and remodeling in the mouse heart.

    Science.gov (United States)

    Seawright, John W; Samman, Yusra; Sridharan, Vijayalakshmi; Mao, Xiao Wen; Cao, Maohua; Singh, Preeti; Melnyk, Stepan; Koturbash, Igor; Nelson, Gregory A; Hauer-Jensen, Martin; Boerma, Marjan

    2017-01-01

    Space travel is associated with an exposure to low-dose rate ionizing radiation and the microgravity environment, both of which may lead to impairments in cardiac function. We used a mouse model to determine short- and long-term cardiac effects to simulated microgravity (hindlimb unloading; HU), continuous low-dose rate γ-irradiation, or a combination of HU and low-dose rate γ-irradiation. Cardiac tissue was obtained from female, C57BL/6J mice 7 days, 1 month, 4 months, and 9 months following the completion of a 21 day exposure to HU or a 21 day exposure to low-dose rate γ-irradiation (average dose rate of 0.01 cGy/h to a total of 0.04 Gy), or a 21 day simultaneous exposure to HU and low-dose rate γ-irradiation. Immunoblot analysis, rt-PCR, high-performance liquid chromatography, and histology were used to assess inflammatory cell infiltration, cardiac remodeling, oxidative stress, and the methylation potential of cardiac tissue in 3 to 6 animals per group. The combination of HU and γ-irradiation demonstrated the strongest increase in reduced to oxidized glutathione ratios 7 days and 1 month after treatment, but a difference was no longer apparent after 9 months. On the other hand, no significant changes in 4-hydroxynonenal adducts was seen in any of the groups, at the measured endpoints. While manganese superoxide dismutase protein levels decreased 9 months after low-dose γ-radiation, no changes were observed in expression of catalase or Nrf2, a transcription factor that determines the expression of several antioxidant enzymes, at the measured endpoints. Inflammatory marker, CD-2 protein content was significantly decreased in all groups 4 months after treatment. No significant differences were observed in α-smooth muscle cell actin protein content, collagen type III protein content or % total collagen. This study has provided the first and relatively broad analysis of small molecule and protein markers of oxidative stress, T-lymphocyte infiltration, and

  4. DNA repair and damage pathway related cancer suppressor genes in low-dose-rate irradiated AKR/J an IR mice

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Hyun Soon; Bong, Jin Jong; Kang, Yumi; Choi, Moo Hyun; Lee, Hae Un; Yoo, Jae Young; Choi, Seung Jin; Kim, Hee Sun [Radiation Health Research Institute, Korea Hydro and Nuclear Power Co., Ltd, Gyeongju (Korea, Republic of); Lee, Kyung Mi [Global Research Lab, BAERI Institute, Dept. of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul (Korea, Republic of)

    2012-11-15

    It has been reported that low-dose-rate radiation stimulates the immune response, prolongs life span and inhibits carcinogenesis. The high dose-rate radiation influences the expression of DNA repair and damage-related genes. In contrast, DNA repair and damage signaling triggered by low-dose-rate irradiation remain unclear. In the present study, we investigated the differential expression of DNA repair and damage pathway related genes in the thymus of AKR/J and ICR mice after 100th day low-dose-rate irradiation. Our findings demonstrated that low-dose-rate γ -radiation suppressed tumorigenesis.

  5. Patient release criteria for low dose rate brachytherapy implants.

    Science.gov (United States)

    Boyce, Dale E; Sheetz, Michael A

    2013-04-01

    A lack of consensus regarding a model governing the release of patients following sealed source brachytherapy has led to a set of patient release policies that vary from institution to institution. The U.S. Nuclear Regulatory Commission has issued regulatory guidance on patient release in NUREG 1556, Volume 9, Rev. 2, Appendix U, which allows calculation of release limits following implant brachytherapy. While the formalism presented in NUREG is meaningful for the calculation of release limits in the context of relatively high energy gamma emitters, it does not estimate accurately the effective dose equivalent for the common low dose rate brachytherapy sources Cs, I, and Pd. NUREG 1556 states that patient release may be based on patient-specific calculations as long as the calculation is documented. This work is intended to provide a format for patient-specific calculations to be used for the consideration of patients' release following the implantation of certain low dose rate brachytherapy isotopes.

  6. Chromosome aberrations and micronucleus in continuously irradiated mice for a low dose rate of {sup 137}Cs {gamma}-rays

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, Jun; Yanai, Takanori; Shirata, Katsutoshi; Tanaka, Kimio; Sato, Fumiaki [Inst. for Environmental Sciences, Rokkasho, Aomori (Japan)

    2002-07-01

    Delayed chromosomal instability is developed by radiation after several cell divisions in cultured rodent and human cells. The genetic instability might be related to cancer development and it has been mainly found in cultured rodent and human cells irradiated at high dose rate. It has not been well studied whether the genetic instability is induced by prolonged irradiation with low dose rate in vivo or not. Mice irradiated with 20 mGy/day for 5-8 Gy were analyzed by FISH to estimate the chromosome aberration rate and micronucleus incidence in spleen and bone marrow cells. Spleen cells in mice exposed to 8 Gy have higher incidence of monosomy and trisomy than non-exposed mice. The number of cells with 2-4 micronuclei in 10,000 scored spleen cells is also higher in 5-8 Gy exposed mice. These numerical chromosome aberrations are not induced directly by radiation exposure. These results indicate that prolonged {sup 137}Cs {gamma} ray-irradiation with low dose rates of 20 mGy/day induces delayed chromosome instability in mice. (author)

  7. Current topics in the treatment of prostate cancer with low-dose-rate brachytherapy.

    Science.gov (United States)

    Stock, Richard G; Stone, Nelson N

    2010-02-01

    The treatment of prostate cancer with low dose rate prostate brachytherapy has grown rapidly in the last 20 years. Outcome analyses performed in this period have enriched understanding of this modality. This article focuses on the development of a real-time ultrasound-guided implant technique, the importance of radiation dose, trimodality treatment of high-risk disease, long-term treatment outcomes, and treatment-associated morbidity.

  8. The enhanced low dose rate sensitivity of a linear voltage regulator with different biases

    Institute of Scientific and Technical Information of China (English)

    Wang Yiyuan; Lu Wu; Ren Diyuan; Guo Qi; Yu Xuefeng; Gao Bo

    2011-01-01

    A linear voltage regulator was irradiated by 60Co γ at high and low dose rates with two bias conditions to investigate the dose rate effect.The devices exhibit enhanced low dose rate sensitivity (ELDRS) under both biases.Comparing the enhancement factors between zero and working biases,it was found that the ELDRS is more severe under zero bias conditions.This confirms that the ELDRS is related to the low electric field in a bipolar structure.The reasons for the change in the line regulation and the maximum drive current were analyzed by combining the principle of linear voltage regulator with irradiation response of the transistors and error amplifier in the regulator.This may be helpful for designing radiation hardened devices.

  9. Effects of orientation of substrate on the enhanced low-dose-rate sensitivity (ELDRS) in NPN transistors

    Institute of Scientific and Technical Information of China (English)

    LU Wu; ZHENG Yu-Zhan; WANG Yi-Yuan; REN Di-Yuan; GUO Qi; WANG Zhi-Kuan; WANG Jian-An

    2011-01-01

    The radiation effects and annealing characteristics of two types of domestic NPN bipolar junction transistors, fabricated with different orientations, were investigated under different dose-rate irradiation. The experimental results show that both types of the NPN transistors exhibit remarkable Enhanced Low-Dose-Rate Sensitivity (ELDRS). After irradiation at high or low dose rate, the excess base current of NPN transistors obviously increased, and the current gain would degrade rapidly. Moreover, the decrease of collector current was also observed. The NPN transistor with (111) orientation was more sensitive to ionizing radiation than that with (100) orientation. The underlying mechanisms of various experimental phenomena are discussed in detail in this paper.

  10. Effects of orientation of substrate on the enhanced low-dose-rate sensitivity (ELDRS) in NPN transistors

    Science.gov (United States)

    Lu, Wu; Zheng, Yu-Zhan; Wang, Yi-Yuan; Ren, Di-Yuan; Guo, Qi; Wang, Zhi-Kuan; Wang, Jian-An

    2011-02-01

    The radiation effects and annealing characteristics of two types of domestic NPN bipolar junction transistors, fabricated with different orientations, were investigated under different dose-rate irradiation. The experimental results show that both types of the NPN transistors exhibit remarkable Enhanced Low-Dose-Rate Sensitivity (ELDRS). After irradiation at high or low dose rate, the excess base current of NPN transistors obviously increased, and the current gain would degrade rapidly. Moreover, the decrease of collector current was also observed. The NPN transistor with orientation was more sensitive to ionizing radiation than that with orientation. The underlying mechanisms of various experimental phenomena are discussed in detail in this paper.

  11. Radiation Exposure

    Science.gov (United States)

    ... on to any children you have after the exposure. A lot of radiation over a short period, ... skin burns and reduced organ function. If the exposure is large enough, it can cause premature aging ...

  12. Dosimetry Modeling for Focal Low-Dose-Rate Prostate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Al-Qaisieh, Bashar [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Mason, Josh, E-mail: joshua.mason@nhs.net [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Bownes, Peter; Henry, Ann [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Dickinson, Louise [Division of Surgery and Interventional Science, University College London, London (United Kingdom); Department of Radiology, Northwick Park Hospital, London North West NHS Trust, London (United Kingdom); Ahmed, Hashim U. [Division of Surgery and Interventional Science, University College London, London (United Kingdom); University College London Hospital, London (United Kingdom); Emberton, Mark [University College London Hospital, London (United Kingdom); Langley, Stephen [St Luke' s Cancer Centre, Guildford (United Kingdom)

    2015-07-15

    Purpose: Focal brachytherapy targeted to an individual lesion(s) within the prostate may reduce side effects experienced with whole-gland brachytherapy. The outcomes of a consensus meeting on focal prostate brachytherapy were used to investigate optimal dosimetry of focal low-dose-rate (LDR) prostate brachytherapy targeted using multiparametric magnetic resonance imaging (mp-MRI) and transperineal template prostate mapping (TPM) biopsy, including the effects of random and systematic seed displacements and interseed attenuation (ISA). Methods and Materials: Nine patients were selected according to clinical characteristics and concordance of TPM and mp-MRI. Retrospectively, 3 treatment plans were analyzed for each case: whole-gland (WG), hemi-gland (hemi), and ultra-focal (UF) plans, with 145-Gy prescription dose and identical dose constraints for each plan. Plan robustness to seed displacement and ISA were assessed using Monte Carlo simulations. Results: WG plans used a mean 28 needles and 81 seeds, hemi plans used 17 needles and 56 seeds, and UF plans used 12 needles and 25 seeds. Mean D90 (minimum dose received by 90% of the target) and V100 (percentage of the target that receives 100% dose) values were 181.3 Gy and 99.8% for the prostate in WG plans, 195.7 Gy and 97.8% for the hemi-prostate in hemi plans, and 218.3 Gy and 99.8% for the focal target in UF plans. Mean urethra D10 was 205.9 Gy, 191.4 Gy, and 92.4 Gy in WG, hemi, and UF plans, respectively. Mean rectum D2 cm{sup 3} was 107.5 Gy, 77.0 Gy, and 42.7 Gy in WG, hemi, and UF plans, respectively. Focal plans were more sensitive to seed displacement errors: random shifts with a standard deviation of 4 mm reduced mean target D90 by 14.0%, 20.5%, and 32.0% for WG, hemi, and UF plans, respectively. ISA has a similar impact on dose-volume histogram parameters for all plan types. Conclusions: Treatment planning for focal LDR brachytherapy is feasible. Dose constraints are easily met with a notable

  13. Regeneration of Murine Hair Follicles is Inhibited by Low-Dose-Rate Gamma Irradiation.

    Science.gov (United States)

    Sugaya, Kimihiko; Hirobe, Tomohisa; Ishihara, Yoshie; Inoue, Sonoe

    2016-10-01

    To determine whether the effects of low-dose-rate gamma (γ) irradiation are identifiable in the regeneration of murine hair follicles, we irradiated whole bodies of C57BL/10JHir mice in the first telogen phase of the hair cycle with (137)Cs γ-rays. The mice were examined for effects on hair follicles, including number, morphology, and pigmentation in the second anagen phase. Effects of γ-radiation on melanocyte stem cells were also investigated by the indirect immunolabeling of tyrosinase-related protein 2 (TRP2). Irradiated skin showed a decrease in hair follicle density and the induction of curved hair follicles along with the presence of white hairs and hypopigmented hair bulbs. There was a small, but not significant, change in the number of TRP2-positive melanocyte stem cells in the hair bulge region of the irradiated skin. These results suggest that low-dose rate γ-irradiation does not deplete melanocyte stem cells, but can damage stem cells and progenitors for both keratinocytes and melanocytes, thereby affecting the structure and pigmentation of regenerated hair follicles in the 2(nd) anagen phase.

  14. Modeling low-dose-rate effects in irradiated bipolar-base oxides

    Energy Technology Data Exchange (ETDEWEB)

    Graves, R.J.; Cirba, C.R.; Schrimpf, R.D.; Milanowski, R.J.; Saigne, F. [Vanderbilt Univ., Nashville, TN (United States); Michez, A. [Univ. Montpellier 2 (France); Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States); Witczak, S.C. [Aerospace Corp., Los Angeles, CA (United States)

    1997-02-01

    A physical model is developed to quantify the contribution of oxide-trapped charge to enhanced low-dose-rate gain degradation in BJTs. Simulations show that space charge limited transport is partially responsible for the low-dose-rate enhancement.

  15. Modeling Low-Dose-Rate Effects in Irradiated Bipolar-Base Oxides

    Energy Technology Data Exchange (ETDEWEB)

    Cirba, C.R.; Fleetwood, D.M.; Graves, R.J.; Michez, A.; Milanowski, R.J.; Saigne, F.; Schrimpf, R.D.; Witczak, S.C.

    1998-10-26

    A physical model is developed to quantify the contribution of oxide-trapped charge to enhanced low-dose-rate gain degradation in bipolar junction transistors. Multiple-trapping simulations show that space charge limited transport is partially responsible for low-dose-rate enhancement. At low dose rates, more holes are trapped near the silicon-oxide interface than at high dose rates, resulting in larger midgap voltage shifts at lower dose rates. The additional trapped charge near the interface may cause an exponential increase in excess base current, and a resultant decrease in current gain for some NPN bipolar technologies.

  16. Enhanced charge trapping in bipolar spacer oxides during low-dose-rate irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fleetwood, D.M.; Reber, R.A. Jr.; Winokur, P.S. [Sandia National Labs., Albuquerque, NM (United States); Kosier, S.L.; Schrimpf, R.D. [Arizona Univ., Tucson, AZ (United States). Dept. of Electrical and Computer Engineering; Nowlin, R.N. [Air Force Phillips Laboratory, Albuquerque, NM (United States); Pease, R.L. [RLP Research, Inc., Albuquerque, NM (United States); DeLaus, M. [Analog Devices, Wilmington, MA (United States)

    1994-03-01

    Thermally-stimulated-current and capacitance-voltage measurements reveal enhanced hole trapping in bipolar spacer-oxide capacitors irradiated at 0 V at low dose rates. Possible mechanisms and implications for bipolar low-rate response are discussed.

  17. Thermal-stress effects on enhanced low-dose-rate sensitivity of linear bipolar circuits

    Energy Technology Data Exchange (ETDEWEB)

    SHANEYFELT,MARTY R.; SCHWANK,JAMES R.; WITCZAK,STEVEN C.; RIEWE,LEONARD CHARLES; WINOKUR,PETER S.; HASH,GERALD L.; PEASE,R.L.; FLEETWOOD,D.M.

    2000-02-17

    Thermal-stress effects are shown to have a significant impact on the enhanced low-dose-rate sensitivity of linear bipolar circuits. Implications of these results on hardness assurance testing and mechanisms are discussed.

  18. Health effects of prolonged low-dose rate gamma-irradiation of a human population in Taiwan, 1983-2003

    Energy Technology Data Exchange (ETDEWEB)

    Chang, W. P.; Hsieh, W. A.; Lin, Y. P.; Huang, S.; Hwang, B. F.; Lee, S. D.; Chen, J. C.; Tsai, M.; Yen, N. P.

    2004-07-01

    Health effects of low dose-rate , low LET irradiation on large numbers of human population have been rare and less well known and studied. However, the standards for safety and health regulation for radiation exposure depend on solid observations of related studies. during 1983 to mid 1990s, an unusual contamination occurred that was derived from several lost Co-60 orphan sources and un-intentionally recycled into thousands tons construction steels, eventually employed for construction in several cities in Taiwan. Continuous studies on the immediate and prolonged health effects of these 7,000 subjects, with more than 60% have been exposed during prenatal, childhood, and adolescents periods, have been able to form a stron scientific avenue to provide evidences for unusual observation on a human population in natural environments. Moreover, an exposure reconstruction program, co-joined with scientists in National Institute of Occupational Safety and Health and Oregan State University in the U. S.; were initiated and continued throughout the study program that critically provided dose response analysis feasible. These studies include bone marrow/hematological changes, lens opacities, thyroid function and thyroid glands abnormalities, growth and development in physical parameters, helper and suppressor T cell populations, serum p53 protein levels, and cancer incidences and risks. Moreover, several cytogenetic markers have been employed to analyze the subtle changes in the somatic tissues. These include frequencies of micronuclei formation, chromosomal aberrations and chromosomal translocations on circulating T-lymphocytes. Functional studies including IQ testing on prenatally exposed children and the reproductive potential as time-to-pregnancy, TTP, were also observed in married couples with offspring. The observations, published in more than 20 manuscripts, will be summarized and presented for future collaborative studies, based on the established database, case

  19. Measurement bias dependence of enhanced bipolar gain degradation at low dose rates

    Energy Technology Data Exchange (ETDEWEB)

    Witczak, S.C.; Lacoe, R.C.; Mayer, D.C. [Aerospace Corp., Los Angeles, CA (United States). Electronics Technology Center; Schrimpf, R.D.; Barnaby, H.J.; Galloway, K.F. [Vanderbilt Univ., Nashville, TN (United States). Dept. of Electrical and Computer Engineering; Pease, R.L. [RLP Research, Inc., Albuquerque, NM (United States); Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States)

    1998-03-01

    Oxide trapped charge, field effects from emitter metallization, and high level injection phenomena moderate enhanced gain degradation of lateral pnp transistors at low dose rates. Hardness assurance tests at elevated irradiation temperatures require larger design margins for low power measurement biases.

  20. Pregnancy and Radiation Exposure

    Science.gov (United States)

    ... RadiationAnswers.org Ask the Experts Pregnancy and Radiation Exposure Robert Brent, MD, PhD The following information pertains to reproductive risks of radiation exposures to women who are pregnant and have questions ...

  1. Method of simulation of low dose rate for total dose effect in 0.18 {mu}m CMOS technology

    Energy Technology Data Exchange (ETDEWEB)

    He Baoping; Yao Zhibin; Guo Hongxia; Luo Yinhong; Zhang Fengqi; Wang Yuanming; Zhang Keying, E-mail: baopinghe@126.co [Northwest Institute of Nuclear Technology, Xi' an 710613 (China)

    2009-07-15

    Three methods for simulating low dose rate irradiation are presented and experimentally verified by using 0.18 {mu}m CMOS transistors. The results show that it is the best way to use a series of high dose rate irradiations, with 100 {sup 0}C annealing steps in-between irradiation steps, to simulate a continuous low dose rate irradiation. This approach can reduce the low dose rate testing time by as much as a factor of 45 with respect to the actual 0.5 rad (Si)/s dose rate irradiation. The procedure also provides detailed information on the behavior of the test devices in a low dose rate environment.

  2. Investigation of bias dependence on enhanced low dose rate sensitivity in SiGe HBTs for space application

    Science.gov (United States)

    Sun, Yabin; Fu, Jun; Xu, Jun; Wang, Yudong; Zhou, Wei; Zhang, Wei; Cui, Jie; Li, Gaoqing; Liu, Zhihong

    2014-02-01

    NPN silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) were exposed to 60Co gamma source at different dose rates under two bias conditions. Excess base currents and normalized current gains are used to quantify performance degradation. Experiment results demonstrate that the lower the dose rate, the more the irradiation damage, and some enhanced low dose rate sensitivity (ELDRS) exists in SiGe HBTs. The ELDRS effect is found to depend highly on the bias condition during exposure, and the transistors with forward active mode exhibit a more serious ELDRS effect compared to the floating case. The performance degradation at different dose rates and bias conditions is compared and discussed, and furthermore the underlying physical mechanisms are analyzed and investigated in detail.

  3. mBAND analysis of chromosome aberrations in human epithelial cells induced by gamma-rays and secondary neutrons of low dose rate.

    Science.gov (United States)

    Hada, M; Gersey, B; Saganti, P B; Wilkins, R; Cucinotta, F A; Wu, H

    2010-08-14

    Human risks from chronic exposures to both low- and high-LET radiation are of intensive research interest in recent years. In the present study, human epithelial cells were exposed in vitro to gamma-rays at a dose rate of 17 mGy/h or secondary neutrons of 25 mGy/h. The secondary neutrons have a broad energy spectrum that simulates the Earth's atmosphere at high altitude, as well as the environment inside spacecrafts like the Russian MIR station and the International Space Station (ISS). Chromosome aberrations in the exposed cells were analyzed using the multicolor banding in situ hybridization (mBAND) technique with chromosome 3 painted in 23 colored bands that allows identification of both inter- and intrachromosome exchanges including inversions. Comparison of present dose responses between gamma-rays and neutron irradiations for the fraction of cells with damaged chromosome 3 yielded a relative biological effectiveness (RBE) value of 26+/-4 for the secondary neutrons. Our results also revealed that secondary neutrons of low dose rate induced a higher fraction of intrachromosome exchanges than gamma-rays, but the fractions of inversions observed between these two radiation types were indistinguishable. Similar to the previous findings after acute radiation exposures, most of the inversions observed in the present study were accompanied by other aberrations. The fractions of complex type aberrations and of unrejoined chromosomal breakages were also found to be higher in the neutron-exposed cells than after gamma-rays. We further analyzed the location of the breaks involved in chromosome aberrations along chromosome 3, and observed hot spots after gamma-ray, but not neutron, exposures.

  4. Low-Dose-Rate Californium-252 Neutron Intracavitary Afterloading Radiotherapy Combined With Conformal Radiotherapy for Treatment of Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Min [Department of Oncology, Armed Police Hospital of Hangzhou, Hangzhou, Zhejiang Province (China); Xu Hongde [Cancer Center, Armed Police Hospital of Hangzhou, Hangzhou, Zhejiang Province (China); Pan Songdan; Lin Shan; Yue Jianhua [Department of Oncology, Armed Police Hospital of Hangzhou, Hangzhou, Zhejiang Province (China); Liu Jianren, E-mail: liujianren0571@hotmail.com [Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang Province (China)

    2012-07-01

    Purpose: To study the efficacy of low-dose-rate californium-252 ({sup 252}Cf) neutron intracavitary afterloading radiotherapy (RT) combined with external pelvic RT for treatment of cervical cancer. Methods and Materials: The records of 96 patients treated for cervical cancer from 2006 to 2010 were retrospectively reviewed. For patients with tumors {<=}4 cm in diameter, external beam radiation was performed (1.8 Gy/day, five times/week) until the dose reached 20 Gy, and then {sup 252}Cf neutron intracavitary afterloading RT (once/week) was begun, and the frequency of external beam radiation was changed to four times/week. For patients with tumors >4 cm, {sup 252}Cf RT was performed one to two times before whole-pelvis external beam radiation. The tumor-eliminating dose was determined by using the depth limit of 5 mm below the mucosa as the reference point. In all patients, the total dose of the external beam radiation ranged from 46.8 to 50 Gy. For {sup 252}Cf RT, the dose delivered to point A was 6 Gy/fraction, once per week, for a total of seven times, and the total dose was 42 Gy. Results: The mean {+-} SD patient age was 54.7 {+-} 13.7 years. Six patients had disease assessed at stage IB, 13 patients had stage IIA, 49 patients had stage IIB, 3 patients had stage IIIA, 24 patients had stage IIIB, and 1 patient had stage IVA. All patients obtained complete tumor regression (CR). The mean {+-} SD time to CR was 23.5 {+-} 3.4 days. Vaginal bleeding was fully controlled in 80 patients within 1 to 8 days. The mean {+-} SD follow-up period was 27.6 {+-} 12.7 months (range, 6-48 months). Five patients died due to recurrence or metastasis. The 3-year survival and disease-free recurrence rates were 89.6% and 87.5 %, respectively. Nine patients experienced mild radiation proctitis, and 4 patients developed radiocystitis. Conclusions: Low-dose-rate {sup 252}Cf neutron RT combined with external pelvic RT is effective for treating cervical cancer, with a low incidence of

  5. Monitoring of radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-01

    The guide specifies the requirements for the monitoring of radiation exposure in instances where radiation is used. In addition to workers, the guide covers students, apprentices and visitors. The guide shall also apply to exposure from natural radiation. However, the monitoring of radiation exposure in nuclear power plants is dealt with in YVL Guide 7.10 and 7.11. The guide defines the concepts relevant to the monitoring of radiation exposure and provides guidelines for determining the necessity of monitoring and subsequently arranging such in different operations. In addition, the guide specifies the criteria for the approval and regulatory control of the dosimetric service.

  6. Monitoring of radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-01

    The guide specifies the requirements for the monitoring of radiation exposure in instances where radiation is used. In addition to workers, the guide covers students, apprentices and visitors. The guide shall also apply to exposure from natural radiation. However, the monitoring of radiation exposure in nuclear power plants is dealt with in YVL Guide 7.10 and 7.11. The guide defines the concepts relevant to the monitoring of radiation exposure and provides guidelines for determining the necessity of monitoring and subsequently arranging such in different operations. In addition, the guide specifies the criteria for the approval and regulatory control of the dosimetric service.

  7. Measurement uncertainty analysis of low-dose-rate prostate seed brachytherapy: post-implant dosimetry.

    Science.gov (United States)

    Gregory, Kent J; Pattison, John E; Bibbo, Giovanni

    2015-03-01

    The minimal dose covering 90 % of the prostate volume--D 90--is arguably the most important dosimetric parameter in low-dose-rate prostate seed brachytherapy. In this study an analysis of the measurement uncertainties in D 90 from low-dose-rate prostate seed brachytherapy was conducted for two common treatment procedures with two different post-implant dosimetry methods. The analysis was undertaken in order to determine the magnitude of D 90 uncertainty, how the magnitude of the uncertainty varied when D 90 was calculated using different dosimetry methods, and which factors were the major contributors to the uncertainty. The analysis considered the prostate as being homogeneous and tissue equivalent and made use of published data, as well as original data collected specifically for this analysis, and was performed according to the Guide to the expression of uncertainty in measurement (GUM). It was found that when prostate imaging and seed implantation were conducted in two separate sessions using only CT images for post-implant analysis, the expanded uncertainty in D 90 values were about 25 % at the 95 % confidence interval. When prostate imaging and seed implantation were conducted during a single session using CT and ultrasound images for post-implant analysis, the expanded uncertainty in D 90 values were about 33 %. Methods for reducing these uncertainty levels are discussed. It was found that variations in contouring the target tissue made the largest contribution to D 90 uncertainty, while the uncertainty in seed source strength made only a small contribution. It is important that clinicians appreciate the overall magnitude of D 90 uncertainty and understand the factors that affect it so that clinical decisions are soundly based, and resources are appropriately allocated.

  8. Low-dose-rate brachytherapy for patients with transurethral resection before implantation in prostate cancer: long-term results

    Energy Technology Data Exchange (ETDEWEB)

    Prada, Pedro J.; Anchuelo, Javier; Blanco, Ana Garcia; Paya, Gema; Cardenal, Juan; Acuña, Enrique; Ferri, Maria [Department of Radiation Oncology, Hospital Universitario Marqués de Valdecilla, Santander, Cantabria (Spain); Vazquez, Andres; Pacheco, Maite; Sanchez, Jesica [Department of Radiation Physics, Hospital Universitario Marqués de Valdecilla, Santander, Cantabria (Spain)

    2016-01-15

    Objectives: We analyzed the long-term oncologic outcome for patients with prostate cancer and transurethral resection who were treated using low-dose-rate (LDR) prostate brachytherapy. Methods and Materials: From January 2001 to December 2005, 57 consecutive patients were treated with clinically localized prostate cancer. No patients received external beam radiation. All of them underwent LDR prostate brachytherapy. Biochemical failure was defined according to the 'Phoenix consensus'. Patients were stratified as low and intermediate risk based on The Memorial Sloan Kettering group definition. Results: The median follow-up time for these 57 patients was 104 months. The overall survival according to Kaplan-Meier estimates was 88% (±6%) at 5 years and 77% (±6%) at 12 years. The 5 and 10 years for failure in tumour-free survival (TFS) was 96% and respectively (±2%), whereas for biochemical control was 94% and respectively (±3%) at 5 and 10 years, 98% (±1%) of patients being free of local recurrence. A patient reported incontinence after treatment (1.7%). The chronic genitourinary complains grade I were 7% and grade II, 10%. At six months 94% of patients reported no change in bowel function. Conclusions: The excellent long-term results and low morbidity presented, as well as the many advantages of prostate brachytherapy over other treatments, demonstrates that brachytherapy is an effective treatment for patients with transurethral resection and clinical organ-confined prostate cancer. (author)

  9. The effects of low dose rate irradiation and thermal aging on reactor structural alloys

    Science.gov (United States)

    Allen, T. R.; Trybus, C. L.; Cole, J. I.

    As part of the EBR-II reactor materials surveillance program, test samples of fifteen different alloys were placed into EBR-II in 1965. The surveillance (SURV) program was intended to determine property changes in reactor structural materials caused by irradiation and thermal aging. In this work, the effect of low dose rate (approximately 2 × 10 -8 dpa/s) irradiation at 380-410°C and long term thermal aging at 371°C on the properties of 20% cold worked 304 stainless steel, 420 stainless steel, Inconel X750, 304/308 stainless weld material, and 17-4 PH steel are evaluated. Doses of up to 6.8 dpa and thermal aging to 2994 days did not significantly affect the density of these alloys. The strength of 304 SS, X750, 17-4 PH, and 304/308 weld material increased with irradiation. In contrast, the strength of 420 stainless steel decreased with irradiation. Irradiation decreased the impact energy in both Inconel X750 and 17-4 PH steel. Thermal aging decreased the impact energy in 17-4 PH steel and increased the impact energy in Inconel X750. Tensile property comparisons of 304 SURV samples with 304 samples irradiated in EBR-II at a higher dose rate show that the higher dose rate samples had greater increases in strength and greater losses in ductility.

  10. Brachytherapy for early oral tongue cancer. Low dose rate to high dose rate

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Hideya [Toyonaka Municipal Hospital, Osaka (Japan); Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Inoue, Toshihiko [Osaka Univ., Suita (Japan). Graduate School of Medicine; Furukawa, Souhei; Kakimoto, Naoya [Osaka Univ., Suita (Japan). Graduate School of Dentistry

    2003-03-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n=341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer. (author)

  11. Brachytherapy for early oral tongue cancer: low dose rate to high dose rate.

    Science.gov (United States)

    Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Furukawa, Souhei; Kakimoto, Naoya; Shimizutani, Kimishige; Inoue, Toshihiko

    2003-03-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n = 341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer.

  12. COMPROMISING EFFECT OF LOW DOSE-RATE TOTAL-BODY IRRADIATION ON ALLOGENEIC BONE-MARROW ENGRAFTMENT

    NARCIS (Netherlands)

    VANOS, R; KONINGS, AWT; DOWN, JD

    1993-01-01

    The protraction of total body irradiation (TBI) to a continuous low dose-rate has been investigated for its effect on donor marrow engraftment in murine bone marrow transplant (BMT) models of varying histocompatibility. Three different BMT combinations were used: syngeneic [B6-Gpi-1a --> B6-Gpi-1b],

  13. COMPROMISING EFFECT OF LOW DOSE-RATE TOTAL-BODY IRRADIATION ON ALLOGENEIC BONE-MARROW ENGRAFTMENT

    NARCIS (Netherlands)

    VAN OS, R; KONINGS, A W T; DOWN, J D

    1993-01-01

    The protraction of total body irradiation (TBI) to a continuous low dose-rate has been investigated for its effect on donor marrow engraftment in murine bone marrow transplant (BMT) models of varying histocompatibility. Three different BMT combinations were used: syngeneic [B6-Gpi-1a --> B6-Gpi-1b],

  14. Characterization of the neutron irradiation system for use in the Low-Dose-Rate Irradiation Facility at Sandia National Laboratories.

    Energy Technology Data Exchange (ETDEWEB)

    Franco, Manuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-08-01

    The objective of this work was to characterize the neutron irradiation system consisting of americium-241 beryllium (241AmBe) neutron sources placed in a polyethylene shielding for use at Sandia National Laboratories (SNL) Low Dose Rate Irradiation Facility (LDRIF). With a total activity of 0.3 TBq (9 Ci), the source consisted of three recycled 241AmBe sources of different activities that had been combined into a single source. The source in its polyethylene shielding will be used in neutron irradiation testing of components. The characterization of the source-shielding system was necessary to evaluate the radiation environment for future experiments. Characterization of the source was also necessary because the documentation for the three component sources and their relative alignment within the Special Form Capsule (SFC) was inadequate. The system consisting of the source and shielding was modeled using Monte Carlo N-Particle transport code (MCNP). The model was validated by benchmarking it against measurements using multiple techniques. To characterize the radiation fields over the full spatial geometry of the irradiation system, it was necessary to use a number of instruments of varying sensitivities. First, the computed photon radiography assisted in determining orientation of the component sources. With the capsule properly oriented inside the shielding, the neutron spectra were measured using a variety of techniques. A N-probe Microspec and a neutron Bubble Dosimeter Spectrometer (BDS) set were used to characterize the neutron spectra/field in several locations. In the third technique, neutron foil activation was used to ascertain the neutron spectra. A high purity germanium (HPGe) detector was used to characterize the photon spectrum. The experimentally measured spectra and the MCNP results compared well. Once the MCNP model was validated to an adequate level of confidence, parametric analyses was performed on the model to optimize for potential

  15. Influence of radiation exposure on our society and epidemiological study

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimoto, Yasuhiko [National Inst. of Radiological Sciences, Chiba (Japan)

    1997-03-01

    A brief epidemiological review of risk assessment of radiation was discussed with respect to two periods; before and after the establishment of the United Nations Scientific Committee on the Effects of Atomic Radiation. Selected topics were the studies of atomic bomb survivors and people living in the contaminated areas due to Chernobyl nuclear power plant accident. An ethical view to ensure that potential social benefits of epidemiology are maximized was emphasized as well as a scientific view. On the other hand it should be recognized that there are the limitations of epidemiological studies on the basis of the observations on man in which the animal-experimental setting generally cannot be controlled over. Informing people about the professional confidence and caution of radiation exposure is needed to resolve social concern associated with low dose, low dose rate of radiation. Also there are guidelines for the investigation of clusters of adverse health events. In the future an appropriate strategy for decontamination might be expected to unusual radiation exposure as a consequence of a nuclear power plant accident. Justification for the implementations can be determined only through the assessment of the effects both on the environment and health of humans after the accident. (author)

  16. [Low-dose rate brachytherapy with locally integrated beta emitters after internal urethrotomy. A pilot project using an animal model].

    Science.gov (United States)

    Weidlich, P; Adam, C; Sroka, R; Lanzl, I; Assmann, W; Stief, C

    2007-09-01

    The treatment of urethral strictures represents an unsolved urological problem. The effect of a (32)P-coated urethral catheter in the sense of low-dose rate brachytherapy to modulate wound healing will be analyzed in an animal experiment. Unfortunately it is not possible to present any results because this is being studied for the first time and there are no experiences with low-dose rate brachytherapy and this form of application in the lower urinary tract. Furthermore the animal experiment will only start in the near future. Both decade-long experiences with radiotherapy to treat benign diseases and our own results of previous studies in otolaryngology and ophthalmology let us expect a significantly lower formation of urethral strictures after internal urethrotomy. This study will contribute to improving the treatment of urethral strictures as demanded in previous papers.

  17. SU-E-T-34: An in Vivo Study On Pulsed Low Dose-Rate Radiotherapy for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B; Cvetkovic, D; Chen, L; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States); Chen, X [Fox Chase Cancer Center, Philadelphia, PA (United States); Virtua Fox Chase Cancer Center, Voorhees, NJ (United States); Zhang, P [Fox Chase Cancer Center, Philadelphia, PA (United States); Sichuan Cancer Hospital, Chengdu (China); Zhang, C [Fox Chase Cancer Center, Philadelphia, PA (United States); Qiqihar Medical University, Qiqihar (China)

    2014-06-01

    Purpose: Re-irradiation with conventional radiotherapy techniques (CRT) may pose significant risks due to high accumulative radiation doses. Pulsed low dose-rate radiotherapy (PLDR) has been used in clinical trials for recurrent cancer treatment. In our previous studies, PLDR irradiation showed significantly lower toxicity than CRT, resulting in much longer survival of mice after PLDR total body irradiation (TBI) than conventional TBI. The purpose of this study was to investigate tumor control efficacy of PLDR treatment for prostate cancer with an animal model of prostate cancer LNCaP. Methods: We used an orthotopic murine model of LNCaP cell line for this study. LNCaP cells were implanted into immune-suppressed male nude mice via surgery. We monitored the tumor growth with MRI. The tumor-bearing mice were allocated into a PLDR(n=9), CRT(n=7), and control group(n=7) randomly. The mice in the PLDR and CRT groups were irradiated with 2Gy dose for one time. For the CRT treatment, the mice received 2Gy at a dose-rate of 300 MU/minute. For the PLDR treatment, the 2Gy dose was further divided into ten pulses of 0.2Gy at the same dose-rate with an interval of 3 minutes between the pulses. Results: Sizable tumor growth delays were observed for the PLDR and CRT groups through weekly MRI scans. The mean values of the normalized tumor volumes (± standard deviation of the mean) were 1.53±0.07, 1.53±0.14, and 1.81±0.09 at one week after treatment, 2.28±0.13, 2.19±0.16, and 3.04±0.25 at two weeks after treatment, and 3.31±0.23, 3.14±0.24 and 4.62±0.49 at three weeks after treatment, for the PLDR, CRT, and control groups, respectively. Conclusion: The PLDR and CRT treatments showed comparable tumor control rates in this study. Our in vivo results indicate that PLDR may be a viable option for treating recurrent prostate cancer due to its equivalent tumor control but low normal tissue toxocities.

  18. Doses from radiation exposure

    CERN Document Server

    Menzel, H G

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

  19. SU-E-T-145: Beam Characteristics of Flattening Filter Free Beams Including Low Dose Rate Setting

    Energy Technology Data Exchange (ETDEWEB)

    Uehara, K; Ogata, T; Nakayama, M; Shinji, T; Nishimura, H; Masutani, T [Kobe Minimally Invasive Cancer Center, Kobe, Hyogo (Japan); Ishihara, T; Ejima, Y; Sasaki, R [Kobe University Hospital, Kobe, Hyogo (Japan)

    2015-06-15

    Purpose: In commissioning of volumetric modulated arc therapy (VMAT), it is necessary to evaluate the beam characteristics of various dose rate settings with potential to use. The aim of this study is to evaluate the beam characteristics of flattened and flattening filter free (FFF) including low dose rate setting. Methods: We used a Varian TrueBeam with Millennium 120 MLC. Both 6 and 10 MV beams with or without flattening filter were used for this study. To evaluate low-dose rate FFF beams, specially-designed leaf sequence files control out-of-field MLC leaf pair at constant dose rate ranging from 80 to 400 MU/min. For dose rate from 80 MU/min to the maximum usable value of all energies, beam output were measured using ionization chamber (CC04, IBA). The ionization chamber was inserted into water equivalent phantom (RT3000-New, R-tech), and the phantom was set with SAD of 100cm. The beam profiles were performed using the 2D diode array (Profiler2, Sun Nuclear). The SSD was set to 90cm and a combined 30cmx30cmx9cm phantom which consisted of solid water slabs was put on the device. All measurement were made using 100MU irradiation for 10cmx10cm jaw-defined field size with a gantry angle of 0°. Results: In all energies, the dose rate dependences with beam output and variation coefficient were within 0.2% and 0.07%, respectively. The flatness and symmetry exhibited small variations (flatness ≤0.1 point and symmetry≤0.3 point at absolute difference). Conclusion: We had studied the characteristics of flattened and FFF beam over the 80 MU/min. Our results indicated that the beam output and profiles of FFF of TrueBeam linac were highly stable at low dose rate setting.

  20. Separation of two sub-groups with different DNA content after treatment of T-47D breast cancer cells with low dose-rate irradiation and intermittent hypoxia.

    Science.gov (United States)

    Mikalsen, Stine Gyland; Jeppesen Edin, Nina; Sandvik, Joe Alexander; Pettersen, Erik Olai

    2017-01-01

    Background Previous studies have shown that combined treatment with internal ultra-low dose-rate irradiation selectively inactivated hypoxic T-47D breast cancer cells after three to five weeks of treatment. However, 2-3% of the hypoxic cells were found to survive and restart proliferation upon re-oxygenation. Purpose To investigate the metastatic potential and characteristics of radiosensitivity of these surviving cells, named T - 47 DS. Material and Methods The T - 47 DS cells were grown in ambient air without irradiation. A cloning experiment identified two sub-groups with different DNA content ([Formula: see text] and [Formula: see text]). Furthermore, radiosensitivity and presence of hyper-radiosensitivity (HRS) was measured by Co-60 challenge irradiation and relative migration was determined by scratch assays. Results The two subpopulations of T - 47 DS had different DNA content; one had abnormally high DNA content ([Formula: see text]) and one had DNA content similar to wild-type T-47D cells ([Formula: see text]). HRS was surprisingly present in cells of the cloned population [Formula: see text], but was absent in cells of both [Formula: see text] and T - 47 DS. The radio response of T - 47 DS, [Formula: see text] at higher radiation doses were similar to that of T-47D cells, and neither subpopulation showed increased migration compared with wild-type T-47D. Conclusion No increase in the risk of metastasis was found and only slight changes in radiosensitivity in response to conventional clinical doses was observed. Thus, the data suggest that if ultra-low dose-rate irradiation is used for targeting the hypoxic tumor fraction, conventional high dose-rate irradiation can be used to eradicate eventual surviving cells as well as cells in the well oxygenated areas of the tumor.

  1. Low dose rate caesium-137 implant time of intracavitary brachytherapy source of a selected oncology center in Ghana

    OpenAIRE

    John Owusu Banahene; Emmanuel Ofori Darko; Baffour Awuah

    2015-01-01

    Background: The treatment time taken for a radioactive source is found to be very important in intracavitary brachytherapy treatment. The duration of the treatment time depends on the prescribed dose requested to a reference point and the calculated dose rate to the same point. The duration of the treatment time of source is found to depend on the tumour stage. In this work, the treatment time of implant has been calculated for a Caesium-137 low dose rate brachytherapy source at an oncology f...

  2. An open-source genetic algorithm for determining optimal seed distributions for low-dose-rate prostate brachytherapy.

    Science.gov (United States)

    McGeachy, P; Madamesila, J; Beauchamp, A; Khan, R

    2015-01-01

    An open source optimizer that generates seed distributions for low-dose-rate prostate brachytherapy was designed, tested, and validated. The optimizer was a simple genetic algorithm (SGA) that, given a set of prostate and urethra contours, determines the optimal seed distribution in terms of coverage of the prostate with the prescribed dose while avoiding hotspots within the urethra. The algorithm was validated in a retrospective study on 45 previously contoured low-dose-rate prostate brachytherapy patients. Dosimetric indices were evaluated to ensure solutions adhered to clinical standards. The SGA performance was further benchmarked by comparing solutions obtained from a commercial optimizer (inverse planning simulated annealing [IPSA]) with the same cohort of 45 patients. Clinically acceptable target coverage by the prescribed dose (V100) was obtained for both SGA and IPSA, with a mean ± standard deviation of 98 ± 2% and 99.5 ± 0.5%, respectively. For the prostate D90, SGA and IPSA yielded 177 ± 8 Gy and 186 ± 7 Gy, respectively, which were both clinically acceptable. Both algorithms yielded reasonable dose to the rectum, with V100 open source SGA was validated that provides a research tool for the brachytherapy community. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  3. DOE 2012 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-10-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site.

  4. DOE 2011 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-12-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2011 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.

  5. DOE 2008 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-10-01

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE. The DOE 2008 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. This report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  6. DOE 2009 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-09-01

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The DOE 2009 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  7. DOE 2010 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-11-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The DOE 2010 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  8. Reaction rate theory of radiation exposure: Effects of the dose rate on mutation frequencies

    CERN Document Server

    Manabe, Yuichiro; Nakamura, Issei

    2014-01-01

    We develop a kinetic reaction model for the cells having the irradiated DNA molecules due to the ionizing radiation exposure. Our theory simultaneously accounts for the time-dependent reactions of the DNA damage, the DNA mutation, the DNA repair, and the proliferation and apoptosis of cells in a tissue with a minimal set of model parameters. In contrast to the existing theories for the radiation exposition, we do not assume the relationships between the total dose and the induced mutation frequency. We show good agreement between theory and experiment. Importantly, our result shows a new perspective that the key ingredient in the study of the irradiated cells is the rate constants depending on the dose rate. Moreover, we discuss the universal scaling function for mutation frequencies due to the irradiation at low dose rates.

  9. Low dose rate caesium-137 implant time of intracavitary brachytherapy source of a selected oncology center in Ghana

    Directory of Open Access Journals (Sweden)

    John Owusu Banahene

    2015-01-01

    Full Text Available Background: The treatment time taken for a radioactive source is found to be very important in intracavitary brachytherapy treatment. The duration of the treatment time depends on the prescribed dose requested to a reference point and the calculated dose rate to the same point. The duration of the treatment time of source is found to depend on the tumour stage. In this work, the treatment time of implant has been calculated for a Caesium-137 low dose rate brachytherapy source at an oncology facility in Ghana. Objective: The objective was to determine how the treatment time of tumours depends on the dose rate to the reference point prescribed by the Oncologists and the dose rate determined by the dosimetrists at the facility. Materials and Method: Depending upon the stage of the cancer, the Oncologist determines the type of treatment modality, source configuration for the cancer patient and positions of both tandem and ovoids in the cervix. Depending also on the tumour stage, two orthogonal radiographic X-ray films are taken using a simulator machine. The treatment machine used in the study is AMRA-Curietron. The maximum activity of the source was 259GBq. It has five channels which is a manual remote afterloader. In clinical practice, the treatment time t is very short(only some few days for such low dose rate brachytherapy source like Cs-137 which lasts only for some few days in comparison with the half life of the Cs-137 source. The mathematical equation for the calculation of treatment time is written as t=D/D. Hence t is the treatment time of the radioactive source of patients undergoing intracavitary brachytherapy treatment, D is prescribed dose to a reference point and D is the dose rate to the same reference point. Results: The calculated treatment time of the Cs-137 brachytherapy source for different source arrangements or channels used in clinical practice at the brachytherapy Centre have been determined. Also provided, are the

  10. Effect of a vitamin D{sub 3}-based nutritional supplement ('Videchol') on carbohydrate metabolism of rats following chronic low dose-rate irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Starikovich, L.S.; Vernikovska, Ya.I.; Vigovska, T.V.; Veliky, M.M. [Lviv Ivan Franko National University, Department of Biochemistry, Lviv (Ukraine); Becerril Aragon, G.A. [Lviv Ivan Franko National University, Department of Biochemistry, Lviv (Ukraine)]. E-mail: gabriel_aragon@mail.ru

    2001-09-01

    In this study we evaluated the effects of the administration of a vitamin D{sub 3} preparation 'Videchol' to chronically irradiated rats (1 cGy day{sup -1}) by the assessment of the activities of several glycolytic enzymes: lactic dehydrogenase (LDH) (EC 1.1.1.28), pyruvate kinase (PK) (EC 2.7.1.40) and hexokinase (HK) (EC 2.7.1.1), in populations of erythroid and myeloid bone marrow cells. Videchol treatment of irradiated rats led to the normalisation of HK and LDH activity at cumulative doses of around 30 cGy in granulocyte-monocyte cells and to normalisation of LDH and PK activities in erythroid cells starting at 20 cGy in comparison with irradiated rats who did not receive Videchol. The reaction kinetic parameters of LDH in erythrocytes changed according to the redistribution pattern of the isozymes throughout the different stages of the experiment. The administration of Videchol to irradiated rats led to a rearrangement of the LDH isozymes ratio characterised by kinetic properties more comparable to those of the controls. Thus, vitamin D{sub 3} appears to induce a normalisation of carbohydrate metabolism in rats chronically irradiated with low dose-rate ionising radiation. (author)

  11. Possible use of EPDM in radioactive waste disposal: Long term low dose rate and short term high dose rate irradiation in aquatic and atmospheric environment

    Science.gov (United States)

    Hacıoğlu, Fırat; Özdemir, Tonguç; Çavdar, Seda; Usanmaz, Ali

    2013-02-01

    In this study, changes in the properties of ethylene propylene diene terpolymer (EPDM) irradiated with different dose rates in ambient atmosphere and aqueous environment were investigated. Irradiations were carried out both with low dose and high dose rate irradiation sources. EPDM samples which were differentiated from each other by peroxide type and 5-ethylidene 2-norbornene (ENB) contents were used. Long term low dose rate irradiations were carried out for the duration of up to 2.5 years (total dose of 1178 kGy) in two different irradiation environments. Dose rates (both high and low), irradiation environments (in aquatic and open to atmosphere), and peroxide types (aliphatic or aromatic) were the parameters studied. Characterization of irradiated EPDM samples were performed by hardness, compression, tensile, dynamic mechanical analysis (DMA), TGA-FTIR, ATR-FTIR, XRD and SEM tests. It was observed that the irradiation in water environment led to a lower degree of degradation when compared to that of irradiation open to atmosphere for the same irradiation dose. In addition, irradiation environment, peroxide type and dose rate had effects on the extent of change in the properties of EPDM. It was observed that EPDM is relatively radiation resistant and a candidate polymer for usage in radioactive waste management.

  12. A mouse model of cytogenetic analysis to evaluate caesium137 radiation dose exposure and contamination level in lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Roch-Lefevre, Sandrine; Martin-Bodiot, Cecile; Gregoire, Eric; Roy, Laurence [Institut de Radioprotection et de Surete Nucleaire (IRSN), Laboratoire de Dosimetrie Biologique (PRP-HOM/SRBE/LDB), Fontenay aux Roses Cedex (France); Desbree, Aurelie [Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-HOM/SDI, Laboratoire d' Evaluation de la Dose Interne, Fontenay aux Roses Cedex (France); Barquinero, Joan Francesc [Institut de Radioprotection et de Surete Nucleaire (IRSN), Laboratoire de Dosimetrie Biologique (PRP-HOM/SRBE/LDB), Fontenay aux Roses Cedex (France); Universitat Autonoma de Barcelona, Unitat d' Antropologia Biologica, Departament de Biologia Animal, Biologia Vegetal i Ecologia, Bellaterra (Spain)

    2016-03-15

    In case of external overexposure to ionizing radiation, an estimation of its genotoxic effects on exposed individuals can be made retrospectively by the measurement of radiation-induced chromosome aberrations on circulating lymphocytes. Compared with external irradiation, intakes of radionuclides may, however, lead to specific features influencing dose distribution at the scale of body, of tissue or even of cell. Therefore, in case of internal contamination by radionuclides, experimental studies, particularly using animal models, are required to better understand mechanisms of their genotoxic effects and to better estimate the absorbed dose. The present study was designed to evaluate a cytogenetic method in mouse peripheral blood lymphocytes that would allow determination of yields and complexities of chromosome aberrations after low-dose rate exposure to {sup 137}Cs delivered in vitro either by irradiation or by contamination. By using M-FISH analysis, we compared the low-dose rate responses observed in mouse to the high-dose rate responses observed both in mouse and in human. Promising similarities between the two species in the relative biological effect evaluation show that our cytogenetic model established in mouse might be useful to evaluate various radiation exposures, particularly relevant in case of intakes of radionuclides. (orig.)

  13. High dose rate versus low dose rate brachytherapy for oral cancer--a meta-analysis of clinical trials.

    Directory of Open Access Journals (Sweden)

    Zhenxing Liu

    Full Text Available OBJECTIVE: To compare the efficacy and safety of high dose rate (HDR and low dose rate (LDR brachytherapy in treating early-stage oral cancer. DATA SOURCES: A systematic search of MEDLINE, EMBASE and Cochrane Library databases, restricted to English language up to June 1, 2012, was performed to identify potentially relevant studies. STUDY SELECTION: Only randomized controlled trials (RCT and controlled trials that compared HDR to LDR brachytherapy in treatment of early-stage oral cancer (stages I, II and III were of interest. DATA EXTRACTION AND SYNTHESIS: Two investigators independently extracted data from retrieved studies and controversies were solved by discussion. Meta-analysis was performed using RevMan 5.1. One RCT and five controlled trials (607 patients: 447 for LDR and 160 for HDR met the inclusion criteria. The odds ratio showed no statistically significant difference between LDR group and HDR group in terms of local recurrence (OR = 1.12, CI 95% 0.62-2.01, overall mortality (OR = 1.01, CI 95% 0.61-1.66 and Grade 3/4 complications (OR = 0.86, CI 95% 0.52-1.42. CONCLUSIONS: This meta-analysis indicated that HDR brachytherapy was a comparable alternative to LDR brachytherapy in treatment of oral cancer. HDR brachytherapy might become a routine choice for early-stage oral cancer in the future.

  14. The effect of low dose rate irradiation on the swelling of 12% cold-worked 316 stainless steel.

    Energy Technology Data Exchange (ETDEWEB)

    Allen, T. R.

    1999-03-02

    In pressurized water reactors (PWRs), stainless steel components are irradiated at temperatures that may reach 400 C due to gamma heating. If large amounts of swelling (>10%) occur in these reactor internals, significant swelling related embrittlement may occur. Although fast reactor studies indicate that swelling should be insignificant at PWR temperatures, the low dose rate conditions experienced by PWR components may possibly lead to significant swelling. To address these issues, JNC and ANL have collaborated to analyze swelling in 316 stainless steel, irradiated in the EBR-II reactor at temperatures from 376-444 C, at dose rates between 4.9 x 10{sup {minus}8} and 5.8 x 10{sup {minus}7} dpa/s, and to doses of 56 dpa. For these irradiation conditions, the swelling decreases markedly at temperatures less than approximately 386 C, with the extrapolated swelling at 100 dpa being around 3%. For temperatures greater than 386 C, the swelling extrapolated to 100 dpa is around 9%. For a factor of two difference in dose rate, no statistically significant effect of dose rate on swelling was seen. For the range of dose rates analyzed, the swelling measurements do not support significant (>10%) swelling of 316 stainless steel in PWRs.

  15. Determination of the survival curve of the cell irradiated with low dose rate neutrons; Determinacao da curva de sobrevivencia de celulas irradiadas com neutrons a baixa taxa de dose

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Bruno M.; Freitas, Marcelo H.A. de; Campos, Tarcisio P.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Silva, Luciana M.; Dias, Consuelo L.F. [Fundacao Ezequiel Dias, Belo Horizonte, MG (Brazil). Dept. de Pesquisa. Lab. de Bioquimica

    2000-07-01

    The effect of the radiation in tissue and cells are a theme of extreme importance and that is receiving large attention more and more now. This work purposes to evaluate the deleterious effects of the neutrons radiation at low dose rate in lineages of human cancerous cells through the analysis of survival curves. Deleterious effects due to radiation of low dose rate (3.8 mSv/hr) were observed in cells of the lineage HeLa S3. Previous studies, in lineage HN5 of tongue carcinoma, showed survive level to 0.2Sv of 80%, compatible to the value of 88,57% 0.4 Sv obtained for HeLa S3. In a close future, with the molecular biology characterization of a great number or possibly all cancer types (that will be accelerated largely with the conclusion of the human genome project), studies like this, can be much more specific, and could determine the efficiency of the neutrons or any other radiation type for each one of those types. Those data would have of great value for the medicine and they would help to plan the treatments better. (author)

  16. Radiation Exposure and Pregnancy

    Science.gov (United States)

    ... radiation (absorbed dose) or to the potential biological effect in tissue exposed to radiation (equivalent dose). Sv or Sievert The International System of Units (SI) unit for dose equivalent equal to 1 joule/kilogram. The sievert has replaced the rem; one ...

  17. Monte Carlo validation and optimisation of detector packaging for spectroscopic dosimetry for in vivo urethral dosimetry during low dose rate brachytherapy.

    Science.gov (United States)

    Nourbehesht, L K; Cutajar, D L; Guatelli, S; Rosenfeld, A B

    2015-09-01

    The urethral mini-dosimeter, developed by the Centre for Medical Radiation Physics, University of Wollongong, uses spectroscopic dosimetry to provide real time point dose measurements along the urethra during low dose rate prostate brachytherapy. Spectroscopic dosimetry uses the measured spectrum of the treatment isotope to estimate the dose rate at the point of measurement, however, the silicon mini-detectors employed in the urethral mini-dosimeter require water proof encapsulation which must be capable of providing electromagnetic shielding without greatly increasing the size of the probe. The introduction of non-tissue equivalent materials within the encapsulation can change the spectrum of radiation incident on the detector, which may influence the application of spectroscopic dosimetry within the urethral dosimeter. The Monte Carlo code Geant4 was adopted to study the effect of encapsulation on the operation of the urethral mini-dosimeter, as well as to determine whether an appropriate thickness of aluminium shielding was possible for electromagnetic screening. The depth dose response and angular dependence of the urethral mini-dosimeter with three thicknesses of aluminium shielding (20, 50, 100 µm) was compared with the urethral mini-dosimeter without aluminium shielding. The aluminium shielding had the effect of increasing the depth dose response (up to 3% within 30 mm and up to 5% within 50 mm), slightly reduced the azimuth angular dependence and slightly increased the polar angular dependence. The 100 µm thick shielding provided the least azimuth angular dependence (±2 %) and provided a polar angular dependence of ±1.4 % within the angles of -45° to 45°.

  18. Permanent interstitial low-dose-rate brachytherapy for patients with low risk prostate cancer. An interim analysis of 312 cases

    Energy Technology Data Exchange (ETDEWEB)

    Badakhshi, Harun; Graf, Reinhold; Budach, Volker; Wust, Peter [University Hospital Berlin, Department for Radiation Oncology of Charite School of Medicine, Berlin (Germany)

    2015-04-01

    The biochemical relapse-free survival (bRFS) rate after treatment with permanent iodine-125 seed implantation (PSI) or combined seeds and external beam radiotherapy (COMB) for clinical stage T1-T2 localized prostate cancer is a clinically relevant endpoint. The goal of this work was to evaluate the influence of relevant patient- and treatment-related factors. The study population comprised 312 consecutive patients treated with permanent seed implantation. All patients were evaluable for analysis of overall survival (OS) and disease-specific survival (DSS), 230 for bRFS, of which 192 were in the PSI group and 38 in the COMB group. The prescribed minimum peripheral dose was 145 Gy for PSI, for COMB 110 Gy implant and external beam radiotherapy of 45 Gy. The median follow-up time was 33 months (range 8-66 months). bRFS was defined as a serum prostate-specific antigen (PSA) level ≤ 0.2 ng/ml at last follow-up. Overall, the actuarial bRFS at 50 months was 88.4 %. The 50-month bRFS rate for PSI and COMB was 90.9 %, and 77.2 %, respectively. In the univariate analysis, age in the categories ≤ 63 and > 63 years (p < 0.00), PSA nadir (≤ 0.5 ng/ml and > 0.5 ng/ml) and PSA bounce (yes/no) were the significant predicting factors for bRFS. None of the other patient and treatment variables (treatment modality, stage, PSA, Gleason score, risk group, number of risk factors, D90 and various other dose parameters) were found to be a statistically significant predictor of 50-month bRFS. The biochemical failure rates were low in this study. As a proof of principle, our large monocenteric analysis shows that low-dose-rate brachytherapy is an effective and safe procedure for patients with early stage prostate cancer. (orig.) [German] Das biochemisch rezidivfreie Ueberleben (bRFS) nach der Brachytherapie mit permanenter Iod-125-Seed-Implantation (PSI) oder in Kombination mit externer Radiotherapie (COMB) ist beim Patienten mit fruehem Prostatakarzinom (T1/T2) ein relevanter

  19. 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 (

  20. DOE 2013 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-11-01

    The Office of Analysis within the U.S. Department of Energy (DOE) Office of Environment, Health, Safety and Security (EHSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2013 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past five-year period, the occupational radiation exposure information has been analyzed in terms of aggregate data, dose to individuals, and dose by site.

  1. Local Tumor Control and Normal Tissue Toxicity of Pulsed Low-Dose Rate Radiotherapy for Recurrent Lung Cancer

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2015-05-01

    Full Text Available Objectives: This study investigates (1 local tumor control and (2 normal tissue toxicity of pulsed low-dose rate radiotherapy (PLDR for recurrent lung cancer. Methods: For study 1, nude mice were implanted with A549 tumors and divided into the following 3 groups: (1 control (n = 10, (2 conventional radiotherapy (RT; n = 10, and (3 PLDR (n = 10. Tumor-bearing mice received 2 Gy daily dose for 2 consecutive days. Weekly magnetic resonance imaging was used for tumor growth monitoring. For study 2, 20 mice received 8 Gy total body irradiation either continuously (n = 10 or 40 × 0.2 Gy pulses with 3-minute intervals (n = 10. Results: For study 1, both conventional RT and PLDR significantly inhibited the growth of A549 xenografts compared with the control group (>35% difference in the mean tumor volume; P .05. For study 2, the average weight was 20.94 ± 1.68 g and 25.69 ± 1.27 g and the survival time was 8 days and 12 days for mice treated with conventional RT and PLDR (P < .05, respectively. Conclusion: This study showed that PLDR could control A549 tumors as effectively as conventional RT, and PLDR induced much less normal tissue toxicity than conventional RT. Thus, PLDR would be a good modality for recurrent lung cancers. Advances in Knowledge: This article reports our results of an in vivo animal investigation of PLDR for the treatment of recurrent cancers, which may not be eligible for treatment because of the dose limitations on nearby healthy organs that have been irradiated in previous treatments. This was the first in vivo study to quantify the tumor control and normal tissue toxicities of PLDR using mice with implanted tumors, and our findings provided evidence to support the clinical trials that employ PLDR treatment techniques.

  2. SU-E-T-546: Use of Implant Volume for Quality Assurance of Low Dose Rate Brachytherapy Treatment Plans

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, D; Kolar, M [Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States)

    2014-06-01

    Purpose: To analyze the application of volume implant (V100) data as a method for a global check of low dose rate (LDR) brachytherapy plans. Methods: Treatment plans for 335 consecutive patients undergoing permanent seed implants for prostate cancer and for 113 patients treated with plaque therapy for ocular melanoma were analyzed. Plaques used were 54 COMS (10 to 20 mm, notched and regular) and 59 Eye Physics EP917s with variable loading. Plots of treatment time x implanted activity per unit dose versus v100 ^.667 were made. V100 values were obtained using dose volume histograms calculated by the treatment planning systems (Variseed 8.02 and Plaque Simulator 5.4). Four different physicists were involved in planning the prostate seed cases; two physicists for the eye plaques. Results: Since the time and dose for the prostate cases did not vary, a plot of implanted activity vs V100 ^.667 was made. A linear fit with no intercept had an r{sup 2} = 0.978; more than 94% of the actual activities fell within 5% of the activities calculated from the linear fit. The greatest deviations were in cases where the implant volumes were large (> 100 cc). Both COMS and EP917 plaque linear fits were good (r{sup 2} = .967 and .957); the largest deviations were seen for large volumes. Conclusions: The method outlined here is effective for checking planning consistency and quality assurance of two types of LDR brachytherapy treatment plans (temporary and permanent). A spreadsheet for the calculations enables a quick check of the plan in situations were time is short (e.g. OR-based prostate planning)

  3. 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.

  4. SU-E-J-232: Feasibility of MRI-Based Preplan On Low Dose Rate Prostate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Y; Tward, J; Rassiah-Szegedi, P; Zhao, H; Sarkar, V; Huang, L; Szegedi, M; Kokeny, K; Salter, B [University of Utah Huntsman Cancer Institute, Salt Lake City, UT (United States)

    2015-06-15

    Purpose: To investigate the feasibility of using MRI-based preplan for low dose rate prostate brachytherapy. Methods: 12 patients who received transrectal ultrasound (TRUS) guided prostate brachytherapy with Pd-103 were retrospectively studied. Our care-standard of the TRUS-based preplan served as the control. One or more prostate T2-weighted wide and/or narrow-field of view MRIs obtained within the 3 months prior to the implant were imported into the MIM Symphony software v6.3 (MIM Software Inc., Cleveland, OH) for each patient. In total, 37 MRI preplans (10 different image sequences with average thickness of 4.8mm) were generated. The contoured prostate volume and the seed counts required to achieve adequate dosimetric coverage from TRUS and MRI preplans were compared for each patient. The effects of different MRI sequences and image thicknesses were also investigated statistically using Student’s t-test. Lastly, the nomogram from the MRI preplan and TRUS preplan from our historical treatment data were compared. Results: The average prostate volume contoured on the TRUS and MRI were 26.6cc (range: 12.6∼41.3cc), and 27.4 cc (range: 14.3∼50.0cc), respectively. Axial MRI thicknesses (range: 3.5∼8.1mm) did not significantly affect the contoured volume or the number of seeds required on the preplan (R2 = 0.0002 and 0.0012, respectively). Four of the MRI sequences (AX-T2, AX-T2-Whole-Pelvis, AX-T2-FSE, and AXIALT2- Hi-Res) showed statistically significant better prostate volume agreement with TRUS than the other seven sequences (P <0.01). Nomogram overlay between the MRI and TRUS preplans showed good agreement; indicating volumes contoured on MRI preplan scan reliably predict how many seeds are needed for implant. Conclusion: Although MRI does not allow for determination of the actual implant geometry, it can give reliable volumes for seed ordering purposes. Our future work will investigate if MRI is sufficient to reliably replace TRUS preplanning in patients

  5. Psychiatric disorders after radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kokai, Masahiro [Hyogo Coll. of Medicine, Nishinomiya (Japan); Soejima, Toshinori; Wang, Shangdong; Shinfuku, Naotaka

    2001-04-01

    This review focuses on the mental and psychological effects of medical radiation exposure, the nuclear accident at Three Mile Island, the Chernobyl disaster, atomic bomb explosions at Nagasaki and Hiroshima, and accidents at nuclear power plants and nuclear waste plants. Studies have shown that anxiety about the adverse effects of radiation in medicine (such as infertility, carcinogenicity, and genotoxicity) and fear for exposure has caused psychiatric disorders. Several studies on the mental health effects of the nuclear accident at Three Mile Island were conducted, and the results indicated that psychiatric distress persisted for a certain period of time, particularly in pregnant women and women who have children, even when no evidence of substantial of radiation exposure is seen clinically. The psychological consequences of the Chernobyl disaster have been investigated continuously, and various problems, e.g., acute stress reaction, neurosis, and psychosis, have been identified, although no physical damage due to the radiation or PTSD have been reported. By contrast, PTSD has been seen in survivors of the Nagasaki and Hiroshima nuclear explosions. A study in Ohio, (United States), which has a nuclear waste plant, investigated PTSD in people living near the plant and found that the symptom level was mild. In general, the most common symptoms among people with mental and psychological disorders due to radiation exposure are depression and anxiety, with many people having associated somatoform disorders, and some people complain of PTSD. Vague anxiety and fear of sequelae, regardless of the exposure dose, appears to cause such psychiatric disorders. Although it is rare for psychiatrists to see such cases of psychiatric disorders due to radiation exposure, their number may increase as psychiatric services become more widely available. (K.H.)

  6. Pulsed-dose-rate and low-dose-rate brachytherapy : Comparison of sparing effects in cells of a radiosensitive and a radioresistant cell line

    NARCIS (Netherlands)

    Pomp, J; Woudstra, EC; Kampinga, HH

    Pulsed-dose-rate regimens are an attractive alternative to continuous low-dose-rate brachytherapy. However, apart from data obtained from modeling, only a few irt vitro results are available for comparing the biological effectiveness of both modalities. Cells of two human cell lines with survival

  7. Radiation exposure in the remote period after the Chernobyl accident caused oxidative stress and genetic effects in Scots pine populations

    Science.gov (United States)

    Volkova, Polina Yu.; Geras'Kin, Stanislav A.; Kazakova, Elizaveta A.

    2017-02-01

    Even 30 years after the Chernobyl accident, biological effects of irradiation are observed in the chronically exposed Scots pine populations. Chronic radiation exposure at dose rates above 50 mGy•yr-1 caused oxidative stress and led to the increase of antioxidants concentrations in these populations. Genetic variability was examined for 6 enzymes and 14 enzymatic loci of 6 Scots pine populations. Dose rates over 10 mGy•yr-1 caused the increased frequency of mutations and changes in genetic structure of Scots pine populations. However, the same dose rates had no effect on enzymatic activities. The results indicate that even relatively low dose rates of radiation can be considered as an ecological factor which should be taken into account for ecological management and radiation protection of biota species.

  8. Total body irradiation (TBI) in pediatric patients. A single-center experience after 30 years of low-dose rate irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Linsenmeier, Claudia; Thoennessen, Daniel; Negretti, Laura; Streller, Tino; Luetolf, Urs Martin [University Hospital Zurich (Switzerland). Dept. of Radiation-Oncology; Bourquin, Jean-Pierre [University Children' s Hospital Zurich (Switzerland). Dept. of Hemato-Oncology; Oertel, Susanne [University Hospital Zurich (Switzerland). Dept. of Radiation-Oncology; Heidelberg Univ. (Germany). Dept. of Radiation Oncology

    2010-11-15

    TBI at the low-dose rate that was generally used here. Conditioning for bone marrow transplantation without radiation is an attractive option, but is not sufficiently effective to completely replace TBI for the most common pediatric indications. (orig.)

  9. Radiation exposure analysis of female nuclear medicine radiation workers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Young [Dept. of Biomedical Engineering Graduate School, Chungbuk National University, Cheongju (Korea, Republic of); Park, Hoon Hee [Dept. of Radiological Technologist, Shingu College, Sungnam (Korea, Republic of)

    2016-06-15

    In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus

  10. Dosimetric Considerations to Determine the Optimal Technique for Localized Prostate Cancer Among External Photon, Proton, or Carbon-Ion Therapy and High-Dose-Rate or Low-Dose-Rate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Georg, Dietmar, E-mail: Dietmar.Georg@akhwien.at [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Hopfgartner, Johannes [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Gòra, Joanna [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Kuess, Peter [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Kragl, Gabriele [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Berger, Daniel [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Hegazy, Neamat [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Goldner, Gregor; Georg, Petra [Department of Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna/Allgemeines Krankenhaus der Stadt Wien, Vienna (Austria)

    2014-03-01

    Purpose: To assess the dosimetric differences among volumetric modulated arc therapy (VMAT), scanned proton therapy (intensity-modulated proton therapy, IMPT), scanned carbon-ion therapy (intensity-modulated carbon-ion therapy, IMIT), and low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy (BT) treatment of localized prostate cancer. Methods and Materials: Ten patients were considered for this planning study. For external beam radiation therapy (EBRT), planning target volume was created by adding a margin of 5 mm (lateral/anterior–posterior) and 8 mm (superior–inferior) to the clinical target volume. Bladder wall (BW), rectal wall (RW), femoral heads, urethra, and pelvic tissue were considered as organs at risk. For VMAT and IMPT, 78 Gy(relative biological effectiveness, RBE)/2 Gy were prescribed. The IMIT was based on 66 Gy(RBE)/20 fractions. The clinical target volume planning aims for HDR-BT ({sup 192}Ir) and LDR-BT ({sup 125}I) were D{sub 90%} ≥34 Gy in 8.5 Gy per fraction and D{sub 90%} ≥145 Gy. Both physical and RBE-weighted dose distributions for protons and carbon-ions were converted to dose distributions based on 2-Gy(IsoE) fractions. From these dose distributions various dose and dose–volume parameters were extracted. Results: Rectal wall exposure 30-70 Gy(IsoE) was reduced for IMIT, LDR-BT, and HDR-BT when compared with VMAT and IMPT. The high-dose region of the BW dose–volume histogram above 50 Gy(IsoE) of IMPT resembled the VMAT shape, whereas all other techniques showed a significantly lower high-dose region. For all 3 EBRT techniques similar urethra D{sub mean} around 74 Gy(IsoE) were obtained. The LDR-BT results were approximately 30 Gy(IsoE) higher, HDR-BT 10 Gy(IsoE) lower. Normal tissue and femoral head sparing was best with BT. Conclusion: Despite the different EBRT prescription and fractionation schemes, the high-dose regions of BW and RW expressed in Gy(IsoE) were on the same order of magnitude. Brachytherapy techniques

  11. Increased Radioresistance to Lethal Doses of Gamma Rays in Mice and Rats after Exposure to Microwave Radiation Emitted by a GSM Mobile Phone Simulator.

    Science.gov (United States)

    Mortazavi, Smj; Mosleh-Shirazi, Ma; Tavassoli, Ar; Taheri, M; Mehdizadeh, Ar; Namazi, Sas; Jamali, A; Ghalandari, R; Bonyadi, S; Haghani, M; Shafie, M

    2013-01-01

    The aim of this study was to investigate the effect of pre-irradiation with microwaves on the induction of radioadaptive response. In the 1(st) phase of the study, 110 male mice were divided into 8 groups. The animals in these groups were exposed/sham-exposed to microwave, low dose rate gamma or both for 5 days. On day six, the animals were exposed to a lethal dose (LD). In the 2(nd) phase, 30 male rats were divided into 2 groups of 15 animals. The 1(st) group received microwave exposure. The 2(nd) group (controls) received the same LD but there was no treatment before the LD. On day 5, all animals were whole-body irradiated with the LD. Statistically significant differences between the survival rate of the mice only exposed to lethal dose of gamma radiation before irradiation with a lethal dose of gamma radiation with those of the animals pre-exposed to either microwave (p=0.02), low dose rate gamma (p=0.001) or both of these physical adapting doses (p=0.003) were observed. Likewise, a statistically significant difference between survival rates of the rats in control and test groups was observed. Altogether, these experiments showed that exposure to microwave radiation may induce a significant survival adaptive response.

  12. Inherited susceptibility and radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Little, J.B. [Harvard School of Public Health, Boston, MA (United States)

    1997-03-01

    There is continuing concern that some people in the general population may have genetic makeups that place them at particularly high risk for radiation-induced cancer. The existence of such a susceptible subpopulation would have obvious implications for the estimation of risks of radiation exposure. Although it has been long known that familial aggregations of cancer do sometimes occur, recent evidence suggests that a general genetic predisposition to cancer does not exist; most cancers occur sporadically. On the other hand, nearly 10% of the known Mendelian genetic disorders are associated with cancer. A number of these involve a familial predisposition to cancer, and some are characterized by an enhanced susceptibility to the induction of cancer by various physical and chemical carcinogens, including ionizing radiation. Such increased susceptibility will depend on several factors including the frequency of the susceptibility gene in the population and its penetrance, the strength of the predisposition, and the degree to which the cancer incidence in susceptible individuals may be increased by the carcinogen. It is now known that these cancer-predisposing genes may be responsible not only for rare familial cancer syndromes, but also for a proportion of the common cancers. Although the currently known disorders can account for only a small fraction of all cancers, they serve as models for genetic predisposition to carcinogen-induced cancer in the general population. In the present report, the author describes current knowledge of those specific disorders that are associated with an enhanced predisposition to radiation-induced cancer, and discusses how this knowledge may bear on the susceptibility to radiation-induced cancer in the general population and estimates of the risk of radiation exposure.

  13. Effects of orientation of substrate on the enhanced low-dose-rate sensitivity (ELDRS) in NPN transistors

    Institute of Scientific and Technical Information of China (English)

    LU Wu; ZHENG Yu-Zhan; WANG Yi-Yuan; REN Di-Yuan; GUO Qi; WANG Zhi-Kuan; WANG Jian-An

    2011-01-01

    The radiation effects and annealing characteristics of two types of domestic NPN bipolar junction transistors, fabricated with different orientations, were investigated under different dose-rate irradiation. The experimental results show that both types o

  14. Radiation Exposure and Thyroid Cancer Risk After the Fukushima Nuclear Power Plant Accident in Comparison with the Chernobyl Accident.

    Science.gov (United States)

    Yamashita, S; Takamura, N; Ohtsuru, A; Suzuki, S

    2016-09-01

    The actual implementation of the epidemiological study on human health risk from low dose and low-dose rate radiation exposure and the comprehensive long-term radiation health effects survey are important especially after radiological and nuclear accidents because of public fear and concern about the long-term health effects of low-dose radiation exposure have increased considerably. Since the Great East Japan earthquake and the Fukushima Daiichi Nuclear Power Plant accident in Japan, Fukushima Prefecture has started the Fukushima Health Management Survey Project for the purpose of long-term health care administration and medical early diagnosis/treatment for the prefectural residents. Especially on a basis of the lessons learned from the Chernobyl accident, both thyroid examination and mental health care are critically important irrespective of the level of radiation exposure. There are considerable differences between Chernobyl and Fukushima regarding radiation dose to the public, and it is very difficult to estimate retrospectively internal exposure dose from the short-lived radioactive iodines. Therefore, the necessity of thyroid ultrasound examination in Fukushima and the intermediate results of this survey targeting children will be reviewed and discussed in order to avoid any misunderstanding or misinterpretation of the high detection rate of childhood thyroid cancer.

  15. High and low dose rate irradiation have opposing effects on cytokine gene expression in human glioblastoma cell lines.

    Science.gov (United States)

    Ross, H J; Canada, A L; Antoniono, R J; Redpath, J L

    1997-01-01

    Effects of radiation on five cytokine expressing human glioblastoma cell lines were studied. In comparison to unirradiated controls, IL-1 beta and IL-6 mRNAs were generally reduced after low (LDR, 1.0 cGy/min) and very low (VLDR, 0.35 cGy/min) dose rate irradiation. In contrast, high (HDR, 200 cGy/min) and intermediate (IDR, 4.1 cGy/min) dose rates increased steady-state levels of IL-1 beta and IL-6 mRNAs. The surviving fraction was generally inversely proportional to the dose rate; however, these glioma cells were unusually susceptible to LDR. In the two cell lines tested, IDR was less cytotoxic than either HDR or LDR irradiation. Although cytokine gene expression had no clear effect on radiation survival in vitro, autologous cytokines could be important to radiation response in vivo by affecting immune response, tumour stroma, vasculature or surrounding tissues. Adjusting dose rates to account for inverse dose rate effects and altered gene expression may be a useful strategy in optimising radiation therapy of glioblastomas.

  16. High and low dose rate irradiation have opposing effects on cytokine gene expression in human glioblastoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Ross, H.J.; Canada, A.L.; Antoniono, R.J.; Redpath, J.L. [California Univ., Irvine, CA (United States)

    1997-01-01

    Effects of radiation on five cytokine expressing human glioblastoma cell lines were studied. In comparison to unirradiated controls, IL-1{beta} and IL-6 mRNAs were generally reduced after low (LDR, 1.0 cGy/min) and very low (VLDR, 0.35 cGy/min) dose rate irradiation. In contrast, high (HDR, 200 cGy/min) and intermediate (IDR, 4.1 cGy/min) dose rates increased steady-state levels of IL-1{beta} and IL-6 mRNAs. The surviving fraction was generally inversely proportional to the dose rate; however, these glioma cells were unusually to susceptible LDR. In the two cell lines tested, IDR was less cytotoxic than either HDR or LDR irradiation. Although cytokine gene expression had no clear effect on radiation survival in vitro, autologous cytokines could be important to radiation response in vivo by affecting immune response, tumour stroma, vasculature or surrounding tissues. Adjusting dose rates to account for inverse dose rate effects and altered gene expression may be a useful strategy in optimising radiation therapy of gliobastomas. (Author).

  17. New approaches to reduce radiation exposure.

    Science.gov (United States)

    Hill, Kevin D; Einstein, Andrew J

    2016-01-01

    Exposure to ionizing radiation is associated with a long-term risk of health effects, including cancer. Radiation exposure to the U.S. population from cardiac imaging has increased markedly over the past three decades. Initiatives to reduce radiation exposure have focused on the tenets of appropriate study "justification" and "optimization" of imaging protocols. This article reviews ways to optimally reduce radiation dose across the spectrum of cardiac imaging.

  18. Neutron dosimetry for low dose rate Cf-252 AT sources and adherence to recent clinical dosimetry protocol for brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, M.J.; Wierzbicki, J.G.; Van den Heuvel, F. [Wayne State Univ., Detroit, MI (United States). Dept. of Radiation Oncology; Martin, R.C. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.

    1997-12-01

    In 1995, the American Association of Physicists in Medicine Task Group 43 (AAPM TG-43) published a protocol obsoleting all mixed-field radiation dosimetry for Cf-252. Recommendations for a new brachytherapy dosimetry formalism made by this Task Group favor quantification of source strength in terms of air kerma rather than apparent Curies or other radiation units. Additionally, representation of this dosimetry data in terms of radial dose functions, anisotropy functions, geometric factors, and dose rate constants are in an angular and radial (spherical) coordinate system as recommended, rather than the along-away dosimetry data (Cartesian coordinate system) currently available. This paper presents the initial results of calculated neutron dosimetry in a water phantom for a Cf-252 applicator tube (AT) type medical source soon available from Oak Ridge National Laboratory (ORNL).

  19. Immunological network activation by low-dose rate irradiation. Analysis of cell populations and cell surface molecules in whole body irradiated mice

    Energy Technology Data Exchange (ETDEWEB)

    Ina, Yasuhiro; Sakai, Kazuo [Central Research Inst. of Electric Power Industry, Low Dose Radiation Research Center, Komae, Tokyo (Japan)

    2003-07-01

    The effects of low-dose rate whole body irradiation on biodefense and immunological systems were investigated using female C57BL/6 (B6) mice. These B6 mice were exposed continuously to {gamma}-rays from a {sup 137}Cs source in the long-term low-dose rate irradiation facility at CRIEPI for 0 - 12 weeks at a dose rate of 0.95 mGy/hr. In the bone marrow, thymus, spleen, lymph nodes, and peripheral blood of the irradiated mice, changes in cell populations and cell surface molecules were examined. The cell surface functional molecules (CD3, CD4, CD8, CD19, CD45R/B220, ICAM-1, Fas, NK-1.1, CXCR4, and CCR5), and activation molecules (THAM, CD28, CD40, CD44H, CD70, B7-1, B7-2, OX-40 antigen, CTLA-4, CD30 ligand, and CD40 ligand) were analyzed by flow cytometry. The percentage of CD4{sup +} T cells and cell surface CD8 molecule expressions on the CD8{sup +} T cells increased significantly to 120-130% after 3 weeks of the irradiation, compared to non-irradiated control mice. On the other hand, the percentage of CD45R/B220{sup +} CD40{sup +} B cells, which is one of the immunological markers of inflammation, infection, tumor, and autoimmune disease, decreased significantly to 80-90% between the 3rd to 5th week of irradiation. There was no significant difference in other cell population rates and cell surface molecule expression. Furthermore, abnormal T cells bearing mutated T cell receptors induced by high-dose rate irradiation were not observed throughout this study. These results suggest that low-dose rate irradiation activates the immunological status of the whole body. (author)

  20. An evaluation of a Low-Dose-Rate (LDR) brachytherapy procedure using a systems engineering & error analysis methodology for health care (SEABH) - (SAVE)

    LENUS (Irish Health Repository)

    Chadwick, Liam

    2012-03-12

    Health Care Failure Modes and Effects Analysis (HFMEA®) is an established tool for risk assessment in health care. A number of deficiencies have been identified in the method. A new method called Systems and Error Analysis Bundle for Health Care (SEABH) was developed to address these deficiencies. SEABH has been applied to a number of medical processes as part of its validation and testing. One of these, Low Dose Rate (LDR) prostate Brachytherapy is reported in this paper. The case study supported the validity of SEABH with respect to its capacity to address the weaknesses of (HFMEA®).

  1. Incidence of Second Malignancies in Prostate Cancer Patients Treated With Low-Dose-Rate Brachytherapy and Radical Prostatectomy

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, Sarah Nicole; Tyldesley, Scott [Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia (Canada); Department of Radiation Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Hamm, Jeremy [Department of Population Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Jiang, Wei Ning [Faculty of Medicine, University of British Columbia, Vancouver, British Columbia (Canada); Keyes, Mira; Pickles, Tom [Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia (Canada); Department of Radiation Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Lapointe, Vince [Department of Medical Physics, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Kahnamelli, Adam [Department of Radiation Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); McKenzie, Michael [Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia (Canada); Department of Radiation Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada); Miller, Stacy [Department of Radiation Oncology, British Columbia Cancer Agency–Centre for the North, Prince George, British Columbia (Canada); Morris, W. James, E-mail: jmorris@bccancer.bc.ca [Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia (Canada); Department of Radiation Oncology, British Columbia Cancer Agency–Vancouver Centre, Vancouver, British Columbia (Canada)

    2014-11-15

    Purpose: To compare the second malignancy incidence in prostate cancer patients treated with brachytherapy (BT) relative to radical prostatectomy (RP) and to compare both groups with the cancer incidence in the general population. Methods and Materials: From 1998 to 2010, 2418 patients were treated with Iodine 125 prostate BT monotherapy at the British Columbia Cancer Agency, and 4015 referred patients were treated with RP. Cancer incidence was compared with the age-matched general population using standardized incidence ratios (SIRs). Pelvic malignancies included invasive and noninvasive bladder cancer and rectal cancer. Cox multivariable analysis was performed with adjustment for covariates to determine whether treatment (RP vs BT) was associated with second malignancy risk. Results: The median age at BT was 66 years and at RP 62 years. The SIR comparing BT patients with the general population was 1.06 (95% confidence interval [CI] 0.91-1.22) for second malignancy and was 1.53 (95% CI 1.12-2.04) for pelvic malignancy. The SIR comparing RP patients with the general population was 1.11 (95% CI 0.98-1.25) for second malignancy and was 1.11 (95% CI 0.82-1.48) for pelvic malignancy. On multivariable analysis, older age (hazard ratio [HR] 1.05) and smoking (HR 1.65) were associated with increased second malignancy risk (P<.0001). Radical prostatectomy was not associated with a decreased second malignancy risk relative to BT (HR 0.90, P=.43), even when excluding patients who received postprostatectomy external beam radiation therapy (HR 1.13, P=.25). Older age (HR 1.09, P<.0001) and smoking (HR 2.17, P=.0009) were associated with increased pelvic malignancy risk. Radical prostatectomy was not associated with a decreased pelvic malignancy risk compared with BT (HR 0.57, P=.082), even when excluding postprostatectomy external beam radiation therapy patients (HR 0.87, P=.56). Conclusions: After adjustment for covariates, BT patients did not have an increased second

  2. Health effects of prenatal radiation exposure.

    Science.gov (United States)

    Williams, Pamela M; Fletcher, Stacy

    2010-09-01

    Pregnant women are at risk of exposure to nonionizing and ionizing radiation resulting from necessary medical procedures, workplace exposure, and diagnostic or therapeutic interventions before the pregnancy is known. Nonionizing radiation includes microwave, ultrasound, radio frequency, and electromagnetic waves. In utero exposure to nonionizing radiation is not associated with significant risks; therefore, ultrasonography is safe to perform during pregnancy. Ionizing radiation includes particles and electromagnetic radiation (e.g., gamma rays, x-rays). In utero exposure to ionizing radiation can be teratogenic, carcinogenic, or mutagenic. The effects are directly related to the level of exposure and stage of fetal development. The fetus is most susceptible to radiation during organogenesis (two to seven weeks after conception) and in the early fetal period (eight to 15 weeks after conception). Noncancer health effects have not been detected at any stage of gestation after exposure to ionizing radiation of less than 0.05 Gy (5 rad). Spontaneous abortion, growth restriction, and mental retardation may occur at higher exposure levels. The risk of cancer is increased regardless of the dose. When an exposure to ionizing radiation occurs, the total fetal radiation dose should be estimated and the mother counseled about the potential risks so that she can make informed decisions about her pregnancy management.

  3. Low-dose rate prostate brachytherapy is well tolerated in patients with a history of inflammatory bowel disease.

    Science.gov (United States)

    Peters, Christopher A; Cesaretti, Jamie A; Stone, Nelson N; Stock, Richard G

    2006-10-01

    We report on the follow-up of 24 patients with a prior history of inflammatory bowel disease (IBD) treated with brachytherapy for early-stage prostate cancer. Twenty-four patients with a history of inflammatory bowel disease (17 with ulcerative colitis (UC), 7 with Crohn's disease [CD]) underwent prostate brachytherapy between 1992 and 2004. Fifteen patients were treated with I-125 implantation and 6 patients were treated with Pd-103 alone or in combination with 45 Gy external beam radiation. Charts were reviewed for all patients, and all living patients were contacted by phone. National Cancer Institute common toxicity scores for proctitis were assigned to all patients. Actuarial risk of late toxicity was calculated by the Kaplan-Meier method. Statistical analysis was performed using SPSS software. Follow-up ranged from 3 to 126 months (median, 48.5 months; mean, 56.8 months). None of the patients experienced Grade 3 or 4 rectal toxicity. Four patients experienced Grade 2 late rectal toxicity. The 5-year actuarial freedom from developing late Grade 2 rectal toxicity was 81%. At a median follow-up of 48.5 months, 23 patients were alive and had no evidence of disease with a median prostate-specific antigen for the sample of 0.1 ng/mL (range, <0.05-0.88 ng/mL). One patient died of other causes unrelated to his prostate cancer. Prostate brachytherapy is well tolerated in patients with a history of controlled IBD. Therefore, brachytherapy should be considered a viable therapeutic option in this patient population.

  4. The role of dose rate in radiation cancer risk: evaluating the effect of dose rate at the molecular, cellular and tissue levels using key events in critical pathways following exposure to low LET radiation.

    Science.gov (United States)

    Brooks, Antone L; Hoel, David G; Preston, R Julian

    2016-08-01

    This review evaluates the role of dose rate on cell and molecular responses. It focuses on the influence of dose rate on key events in critical pathways in the development of cancer. This approach is similar to that used by the U.S. EPA and others to evaluate risk from chemicals. It provides a mechanistic method to account for the influence of the dose rate from low-LET radiation, especially in the low-dose region on cancer risk assessment. Molecular, cellular, and tissues changes are observed in many key events and change as a function of dose rate. The magnitude and direction of change can be used to help establish an appropriate dose rate effectiveness factor (DREF). Extensive data on key events suggest that exposure to low dose-rates are less effective in producing changes than high dose rates. Most of these data at the molecular and cellular level support a large (2-30) DREF. In addition, some evidence suggests that doses delivered at a low dose rate decrease damage to levels below that observed in the controls. However, there are some data human and mechanistic data that support a dose-rate effectiveness factor of 1. In summary, a review of the available molecular, cellular and tissue data indicates that not only is dose rate an important variable in understanding radiation risk but it also supports the selection of a DREF greater than one as currently recommended by ICRP ( 2007 ) and BEIR VII (NRC/NAS 2006 ).

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

    Directory of Open Access Journals (Sweden)

    Dörr Harald

    2011-11-01

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

  6. DOE occupational radiation exposure 2006 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE. This report provides a summary and an analysis of occupational radiation exposure information for all monitored individuals associated with DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.

  7. DOE occupational radiation exposure 2005 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2005-12-31

    The U.S. Department of Energy (DOE) Offi ce of Corporate Safety Analysis (HS-30) within the Office of Health Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE. This report provides a summary and an analysis of occupational radiation exposure information for all monitored individuals associated with the DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  8. Health effects of low doses at low dose rates: dose-response relationship modeling in a cohort of workers of the nuclear industry; Effets sanitaires des faibles doses a faibles debits de dose: modelisation de la relation dose-reponse dans une cohorte de travailleurs du nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Metz-Flamant, Camille

    2011-09-19

    exposure. Our study finds a risk of leukemia associated with chronic external exposure and allows taking into account modifying factors of this relation. Additional follow-up allows to improve the precision of the estimated dose-response relationship. A combined analysis including the present cohort and other nuclear cohorts could quantify more precisely the risks associated with low doses at low dose rates, in order to validate current underlying hypotheses of the radiation protection system. (author)

  9. DOE Occupational Radiation Exposure, 2001 report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2001-12-31

    The goal of the U.S. Department of Energy (DOE) is to conduct its operations, including radiological, to ensure the safety and health of all DOE employees, contractors, and subcontractors. The DOE strives to maintain radiation exposures to its workers below administrative control levels and DOE limits and to further reduce these exposures to levels that are “As Low As Reasonably Achievable” (ALARA). The 2001 DOE Occupational Radiation Exposure Report provides a summary and analysis of the occupational radiation exposure received by individuals associated with DOE activities. The DOE mission includes stewardship of the nuclear weapons stockpile and the associated facilities, environmental restoration of DOE, and energy research.

  10. DOE occupational radiation exposure 2007 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2007-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The annual DOEOccupational Radiation Exposure 2007 Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and ALARA process requirements. In addition the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. This report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.

  11. Solar Variability and the Near-Earth Environment: Mining Enhanced Low Dose Rate Sensitivity Data From the Microelectronics and Photonics Test Bed Space Experiment

    Science.gov (United States)

    Turflinger, T.; Schmeichel, W.; Krieg, J.; Titus, J.; Campbell, A.; Reeves, M.; Marshall (P.); Hardage, Donna (Technical Monitor)

    2004-01-01

    This effort is a detailed analysis of existing microelectronics and photonics test bed satellite data from one experiment, the bipolar test board, looking to improve our understanding of the enhanced low dose rate sensitivity (ELDRS) phenomenon. Over the past several years, extensive total dose irradiations of bipolar devices have demonstrated that many of these devices exhibited ELDRS. In sensitive bipolar transistors, ELDRS produced enhanced degradation of base current, resulting in enhanced gain degradation at dose rates 1 rd(Si)/s. This Technical Publication provides updated information about the test devices, the in-flight experiment, and both flight-and ground-based observations. Flight data are presented for the past 5 yr of the mission. These data are compared to ground-based data taken on devices from the same date code lots. Information about temperature fluctuations, power shutdowns, and other variables encountered during the space flight are documented.

  12. Minimizing radiation exposure during percutaneous nephrolithotomy.

    Science.gov (United States)

    Chen, T T; Preminger, G M; Lipkin, M E

    2015-12-01

    Given the recent trends in growing per capita radiation dose from medical sources, there have been increasing concerns over patient radiation exposure. Patients with kidney stones undergoing percutaneous nephrolithotomy (PNL) are at particular risk for high radiation exposure. There exist several risk factors for increased radiation exposure during PNL which include high Body Mass Index, multiple access tracts, and increased stone burden. We herein review recent trends in radiation exposure, radiation exposure during PNL to both patients and urologists, and various approaches to reduce radiation exposure. We discuss incorporating the principles of As Low As reasonably Achievable (ALARA) into clinical practice and review imaging techniques such as ultrasound and air contrast to guide PNL access. Alternative surgical techniques and approaches to reducing radiation exposure, including retrograde intra-renal surgery, retrograde nephrostomy, endoscopic-guided PNL, and minimally invasive PNL, are also highlighted. It is important for urologists to be aware of these concepts and techniques when treating stone patients with PNL. The discussions outlined will assist urologists in providing patient counseling and high quality of care.

  13. Assessment of internal radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae Young; Chang, S. Y.; Lee, J. I.; Kim, J. S.; Song, M. Y. [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-05-01

    This report describes the contents and results for implementation of internal radiation monitoring programme, measurement of uranium lung deposition by lung counter and assessment of committed effective dose for radiation workers of KNFC. The aim of radiation protection was achieved by implementing this activity. 9 refs., 8 tabs. (Author)

  14. Monitoring occupational exposure to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Button, J.B.C. [Radiation Safety Consultancy, Engadine, NSW (Australia)

    1997-12-31

    A brief overview is presented of methods of monitoring occupational exposure to ionizing radiation together with reasons for such monitoring and maintaining dose histories of radiation occupationally exposed persons. The various Australian providers of external radiation monitoring services and the types of dosemeters they supply are briefly described together with some monitoring results. Biological monitoring methods, are used to determine internal radiation dose. Whole body monitors, used for this purpose are available at Australian Radiation Lab., ANSTO and a few hospitals. Brief mention is made of the Australian National Radiation Dose Register and its objectives. 8 refs., 9 tabs.

  15. Vanguards of Paradigm Shift in Radiation Biology: Radiation-Induced Adaptive and Bystander Responses

    OpenAIRE

    MATSUMOTO, Hideki; Hamada, Nobuyuki; Takahashi, Akihisa; Kobayashi, Yasuhiko; Ohnishi, Takeo

    2007-01-01

    The risks of exposure to low dose ionizing radiation (below 100 mSv) are estimated by extrapolating from data obtained after exposure to high dose radiation, using a linear no-threshold model (LNT model). However, the validity of using this dose-response model is controversial because evidence accumulated over the past decade has indicated that living organisms, including humans, respond differently to low dose/low dose-rate radiation than they do to high dose/high dose-rate radiation. In oth...

  16. Late Urinary Side Effects 10 Years After Low-Dose-Rate Prostate Brachytherapy: Population-Based Results From a Multiphysician Practice Treating With a Standardized Protocol and Uniform Dosimetric Goals

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, Mira, E-mail: mkeyes@bccancer.bc.ca; Miller, Stacy; Pickles, Tom; Halperin, Ross; Kwan, Winkle; Lapointe, Vincent; McKenzie, Michael; Spadinger, Ingrid; Pai, Howard; Chan, Elisa K.; Morris, W. James

    2014-11-01

    Purpose: To determine late urinary toxicity (>12 months) in a large cohort of uniformly treated low-dose-rate prostate brachytherapy patients. Methods and Materials: From 1998 to 2009, 2709 patients with National Comprehensive Cancer Network–defined low-risk and low-tier intermediate-risk prostate cancer were treated with Iodine 125 ({sup 125}I) low-dose-rate prostate brachytherapy; 2011 patients with a minimum of 25 months of follow-up were included in the study. Baseline patients, treatment, implant factors, and late urinary toxicity (Radiation Therapy Oncology Group [RTOG] grading system and International Prostate Symptom Score [IPSS]) were recorded prospectively. Time to IPSS resolution, late RTOG genitourinary toxicity was examined with Kaplan-Meier and log-rank tests. Cox proportional hazards regression was done for individual covariates and multivariable models. Results: Median follow-up was 54.5 months (range, 2-13 years). Actuarial toxicity rates reached 27% and 10% (RTOG ≥2 and ≥3, respectively) at 9-13 years. Symptoms resolved quickly in the majority of patients (88% in 6-12 months). The prevalence of RTOG 0, 1, 2, 3, and 4 toxicity with a minimum of 7 years' follow-up was 70%, 21%, 6.4%, 2.3%, and 0.08%, respectively. Patients with a larger prostate volume, higher baseline IPSS, higher D90, acute toxicity, and age >70 years had more late RTOG ≥2 toxicity (all P≤.02). The IPSS resolved slower in patients with lower baseline IPSS and larger ultrasound prostate volume, those not receiving androgen deprivation therapy, and those with higher D90. The crude rate of RTOG 3 toxicity was 6%. Overall the rate of transurethral resection of the prostate was 1.9%; strictures, 2%; incontinence, 1.3%; severe symptoms, 1.8%; late catheterization, 1.3%; and hematuria, 0.8%. The majority (80%) resolved their symptoms in 6-12 months. Conclusion: Long-term urinary toxicity after brachytherapy is low. Although actuarial rates increase with longer

  17. Repair of I-SceI induced DSB at a specific site of chromosome in human cells: influence of low-dose, low-dose-rate gamma-rays.

    Science.gov (United States)

    Yatagai, Fumio; Suzuki, Masao; Ishioka, Noriaki; Ohmori, Hitoshi; Honma, Masamitsu

    2008-11-01

    We investigated the influence of low-dose, low-dose-rate gamma-ray irradiation on DNA double strand break (DSB) repair in human lymphoblastoid TK6 cells. A single DSB was introduced at intron 4 of the TK+ allele (chromosome 17) by transfection with the I-SceI expression vector pCBASce. We assessed for DSB repair due to non-homologous end-joining (NHEJ) by determining the generation of TK-deficient mutants in the TK6 derivative TSCE5 (TK +/-) carrying an I-SceI recognition site. We similarly estimated DSB repair via homologous recombination (HR) at the same site in the derived compound heterozygote (TK-/-) cell line TSCER2 that carries an additional point mutation in exon 5. The NHEJ repair of DSB was barely influenced by pre-irradiation of the cells with 30 mGy gamma-rays at 1.2 mGy h(-1). DSB repair by HR, in contrast, was enhanced by approximately 50% after pre-irradiation of the cells under these conditions. Furthermore, when I-SceI digestion was followed by irradiation at a dose of 8.5 mGy, delivered at a dose rate of only 0.125 mGy h(-1), HR repair efficiency was enhanced by approximately 80%. This experimental approach can be applied to characterize DSB repair in the low-dose region of ionizing radiation.

  18. Real Time Radiation Exposure And Health Risks

    Science.gov (United States)

    Hu, Shaowen; Barzilla, Janet E.; Semones, Edward J.

    2015-01-01

    Radiation from solar particle events (SPEs) poses a serious threat to future manned missions outside of low Earth orbit (LEO). Accurate characterization of the radiation environment in the inner heliosphere and timely monitoring the health risks to crew are essential steps to ensure the safety of future Mars missions. In this project we plan to develop an approach that can use the particle data from multiple satellites and perform near real-time simulations of radiation exposure and health risks for various exposure scenarios. Time-course profiles of dose rates will be calculated with HZETRN and PDOSE from the energy spectrum and compositions of the particles archived from satellites, and will be validated from recent radiation exposure measurements in space. Real-time estimation of radiation risks will be investigated using ARRBOD. This cross discipline integrated approach can improve risk mitigation by providing critical information for risk assessment and medical guidance to crew during SPEs.

  19. Cancer risks after radiation exposures

    Energy Technology Data Exchange (ETDEWEB)

    Voelz, G.L.

    1980-01-01

    A general overview of the effects of ionizing radiation on cancer induction is presented. The relationship between the degree of risk and absorbed dose is examined. Mortality from radiation-induced cancer in the US is estimated and percentages attributable to various sources are given. (ACR)

  20. Applied physics of external radiation exposure dosimetry and radiation protection

    CERN Document Server

    Antoni, Rodolphe

    2017-01-01

    This book describes the interaction of living matter with photons, neutrons, charged particles, electrons and ions. The authors are specialists in the field of radiation protection. The book synthesizes many years of experiments with external radiation exposure in the fields of dosimetry and radiation shielding in medical, industrial and research fields. It presents the basic physical concepts including dosimetry and offers a number of tools to be used by students, engineers and technicians to assess the radiological risk and the means to avoid them by calculating the appropriate shields. The theory of radiation interaction in matter is presented together with empirical formulas and abacus. Numerous numerical applications are treated to illustrate the different topics. The state of the art in radiation protection and dosimetry is presented in detail, especially in the field of simulation codes for external exposure to radiation, medical projects and advanced research. Moreover, important data spread in differ...

  1. Accelerated Partial Breast Irradiation With Low-Dose-Rate Interstitial Implant Brachytherapy After Wide Local Excision: 12-Year Outcomes From a Prospective Trial

    Energy Technology Data Exchange (ETDEWEB)

    Hattangadi, Jona A. [Harvard Radiation Oncology Program, Boston, MA (United States); Powell, Simon N. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); MacDonald, Shannon M.; Mauceri, Thomas; Ancukiewicz, Marek [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Freer, Phoebe [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Lawenda, Brian [21st Century Oncology, Las Vegas, NV (United States); Alm El-Din, Mohamed A. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Department of Clinical Oncology, Tanta University Hospital, Tanta (Egypt); Gadd, Michele A.; Smith, Barbara L. [Department of Surgical Oncology, Massachusetts General Hospital, Boston, MA (United States); Taghian, Alphonse G., E-mail: ataghian@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States)

    2012-07-01

    Purpose: To evaluate the long-term toxicity, cosmesis, and local control of accelerated partial breast irradiation with implant brachytherapy after wide local excision for Stage T1N0 breast cancer (BCa). Materials and Methods: Between 1997 and 2001, 50 patients with Stage T1N0M0 BCa were treated in a Phase I-II protocol using low-dose-rate accelerated partial breast irradiation with implant brachytherapy after wide local excision and lymph node surgery. The total dose was escalated in three groups: 50 Gy (n = 20), 55 Gy (n = 17), and 60 Gy (n = 13). Patient- and physician-assessed breast cosmesis, patient satisfaction, toxicity, mammographic abnormalities, repeat biopsies, and disease status were prospectively evaluated at each visit. Kendall's tau ({tau}{sub {beta}}) and logistic regression analyses were used to correlate outcomes with dose, implant volume, patient age, and systemic therapy. Results: The median follow-up period was 11.2 years (range, 4-14). The patient satisfaction rate was 67%, 67% reported good-excellent cosmesis, and 54% had moderate-severe fibrosis. Higher dose was correlated with worse cosmetic outcome ({tau}{sub {beta}} 0.6, p < .0001), lower patient satisfaction ({tau}{sub {beta}} 0.5, p < .001), and worse fibrosis ({tau}{sub {beta}} 0.4, p = .0024). Of the 50 patients, 35% had fat necrosis and 34% developed telangiectasias {>=}1 cm{sup 2}. Grade 3-4 late skin and subcutaneous toxicities were seen in 4 patients (9%) and 6 patients (13%), respectively, and both correlated with higher dose ({tau}{sub {beta}} 0.3-0.5, p {<=} .01). One patient had Grade 4 skin ulceration and fat necrosis requiring surgery. Mammographic abnormalities were seen in 32% of the patients, and 30% underwent repeat biopsy, of which 73% were benign. Six patients had ipsilateral breast recurrence: five elsewhere in the breast, and one at the implant site. One patient died of metastatic BCa after recurrence. The 12-year actuarial local control, recurrence

  2. Ionising radiation exposure in the Netherlands

    NARCIS (Netherlands)

    Eleveld H; LSO

    2003-01-01

    The Dutch population is exposed to ionising radiation from various sources, both natural and man-made. This is a review of the radiation exposure for members of the public from all sources for the year 2000. The average annual effective dose per capita is estimated at 2.5 mSv, which is almost the

  3. Ultraviolet Radiation: Human Exposure and Health Risks.

    Science.gov (United States)

    Tenkate, Thomas D.

    1998-01-01

    Provides an overview of human exposure to ultraviolet radiation and associated health effects as well as risk estimates for acute and chronic conditions resulting from such exposure. Demonstrates substantial reductions in health risk that can be achieved through preventive actions. Also includes a risk assessment model for skin cancer. Contains 36…

  4. Low dose rate vaginal brachytherapy of endometrial adenocarcinomas; Curietherapie vaginale postoperatoire des adenocarcinomes de l`endometre a bas debit de dose

    Energy Technology Data Exchange (ETDEWEB)

    Charra-Brumaud, C.; Peiffert, D.; Hoffstetter, S.; Luporsi, E.; Guillemin, F.; Bey, P. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France)

    1998-01-01

    Surgery is the primary treatment for endometrial carcinoma. Methods of complementary treatment are still debated, with the potential association of external radiotherapy and/or brachytherapy before or after surgery. This study was aimed at evaluating local control and complication rates in a series of patients treated by hysterectomy followed by postoperative vaginal low-dose rate brachytherapy (BT) combined with pelvic irradiation in case of poor prognosis factors. From 1978 to 1993, 101 patients were treated at the Centre Alexis-Vautrin, France according to this scheme. Forty five had deep myometrial invasion, and thirteen cervical involvement. Fifty patients received pelvic irradiation (median dose 46 Gy) combined with BT (dose 14 Gy, median volume 127 cm{sup 3}); 51 patients had BT alone (dose 60 Gy, median volume 71 cm{sup 3}). The 5-year overall survival rate was 83 % and the local control rate 97 % with a median follow-up of 7 years. Multivariate analysis showed two factors of bad prognosis, i.e. deep myometrial invasion and cervical involvement. Three severe complications occurred in two patients for whom the treated volume was larger than the theoretical target volume. Eleven patients developed metastases. Results obtained from this series are comparable with those of previous studies, particularly in regard to pre-operative BT. The complication rate is also satisfactory and depends on the irradiation precision and the definition of the target volume. (authors)

  5. Radiation exposure in the moon environment

    Science.gov (United States)

    Reitz, Guenther; Berger, Thomas; Matthiae, Daniel

    2012-12-01

    During a stay on the moon humans are exposed to elevated radiation levels due to the lack of substantial atmospheric and magnetic shielding compared to the Earth's surface. The absence of magnetic and atmospheric shielding allows cosmic rays of all energies to impinge on the lunar surface. Beside the continuous exposure to galactic cosmic rays (GCR), which increases the risk of cancer mortality, exposure through particles emitted in sudden nonpredictable solar particle events (SPE) may occur. SPEs show an enormous variability in particle flux and energy spectra and have the potential to expose space crew to life threatening doses. On Earth, the contribution to the annual terrestrial dose of natural ionizing radiation of 2.4 mSv by cosmic radiation is about 1/6, whereas the annual exposure caused by GCR on the lunar surface is roughly 380 mSv (solar minimum) and 110 mSv (solar maximum). The analysis of worst case scenarios has indicated that SPE may lead to an exposure of about 1 Sv. The only efficient measure to reduce radiation exposure is the provision of radiation shelters. Measurements on the lunar surface performed during the Apollo missions cover only a small energy band for thermal neutrons and are not sufficient to estimate the exposure. Very recently some data were added by the Radiation Dose Monitoring (RADOM) instrument operated during the Indian Chandrayaan Mission and the Cosmic Ray Telescope (CRaTER) instrument of the NASA LRO (Lunar Reconnaisance Orbiter) mission. These measurements need to be complemented by surface measurements. Models and simulations that exist describe the approximate radiation exposure in space and on the lunar surface. The knowledge on the radiation exposure at the lunar surface is exclusively based on calculations applying radiation transport codes in combination with environmental models. Own calculations are presented using Monte-Carlo simulations to calculate the radiation environment on the moon and organ doses on the

  6. 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.

  7. Atmospheric Ionizing Radiation and Human Exposure

    Science.gov (United States)

    Wilson, John W.; Mertens, Christopher J.; Goldhagen, Paul; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2005-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes. especially along the coastal plain and interior low lands, and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  8. OCCUPATIONAL EXPOSURE TO EXTERNAL RADIATION IN SWITZERLAND.

    Science.gov (United States)

    Mayer, S; Baechler, S; Damet, J; Elmiger, R; Frei, D; Giannini, S; Leupin, A; Sarott, F; Schuh, R

    2016-09-01

    Individual monitoring for both external and internal exposures is well regulated in Switzerland. The article gives an overview on the occupational exposure to external radiation of workers based on the data collected in the Swiss national dose registry (NDR) in 2013. The NDR records the monthly doses of radiation workers since the introduction of ICRP 60 recommendations and is manifested in the Swiss ordinance since 1994. Annual dose limits for effective dose are typically exceeded once a year in Switzerland, mostly in medicine. The NDR is a useful optimisation tool to identify and characterise areas with the highest exposures. While exceeded dose limits were often related to accidental acute exposure in the past, they are now more related to continuous exposure during normal work, especially in medicine.

  9. Dose Response for Chromosome Aberrations in Human Lymphocytes and Fibroblasts after Exposure to Very Low Doses of High LET Radiation

    Science.gov (United States)

    Hada, M.; George, Kerry; Cucinotta, Francis A.

    2011-01-01

    The relationship between biological effects and low doses of absorbed radiation is still uncertain, especially for high LET radiation exposure. Estimates of risks from low-dose and low-dose-rates are often extrapolated using data from Japanese atomic bomb survivors with either linear or linear quadratic models of fit. In this study, chromosome aberrations were measured in human peripheral blood lymphocytes and normal skin fibroblasts cells after exposure to very low dose (1-20 cGy) of 170 MeV/u Si-28- ions or 600 MeV/u Fe-56-ions. Chromosomes were analyzed using the whole chromosome fluorescence in situ hybridization (FISH) technique during the first cell division after irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving greater than 2 breaks in 2 or more chromosomes). The curves for doses above 10 cGy were fitted with linear or linear-quadratic functions. For Si-28- ions no dose response was observed in the 2-10 cGy dose range, suggesting a non-target effect in this range.

  10. Prenatal radiation exposure policy: A labor arbitration

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, J.J. (New York Power Authority, White Plains (USA))

    1990-07-01

    A policy on prenatal radiation exposure at two nuclear power plants was revised to give better assurance of compliance with NCRP recommendations on fetal radiation exposure. This action was taken after publication of NCRP 91 in June 1987 to provide better assurance that a total dose equivalent limit to an embryo-fetus be no greater than 0.5 mSv (0.05 rem) in any month and no more than 5 mSv (500 mrem) for a gestation period. For any female worker to receive radiation exposure greater than 1.5 mSv (0.15 rem) in a month at these nuclear power plants, she was asked to initiate an administrative request for radiation exposure in excess of this limit. In this request, she was asked to acknowledge that she was aware of the guidance in U.S. NRC Regulatory Guide 8.13. A worker who had the potential for radiation exposure in excess of 1.5 mSv (0.15 rem) refused to process this request and was consequently denied overtime work. She filed a grievance for denial of overtime, and this grievance was submitted for labor arbitration in June 1988. The arbitration decision and its basis and related NRC actions are discussed.

  11. In-flight radiation exposure during pregnancy.

    Science.gov (United States)

    Barish, Robert J

    2004-06-01

    During high-altitude flight, the cosmic radiation dose rate in an airliner is greater than it is at ground level. For a casual traveler, the impact on pregnancy from cosmic radiation exposure during flight is trivial. Pregnant frequent flyers, pilots, and flight attendants can, however, receive exposures that exceed current recommended values if they do not appropriately modify their work schedules. In addition to the galactic cosmic-ray background that is the source of this radiation, severe disturbances on the sun may cause eruptions that significantly raise radiation levels at airliner altitudes for brief periods, possibly having an impact even on casual travelers. This article will help obstetrician-gynecologists provide advice to their pregnant patients about in-flight radiation risks. That advice should be influenced by an understanding of recommended radiation exposure limits and a perspective on how those limits relate to the potential for real harm. Resources provided by the U.S. Federal Aviation Administration and others to help pregnant women and their physicians make informed decisions about the acceptability of this type of exposure are described.

  12. Cranial radiation exposure during cerebral catheter angiography.

    Science.gov (United States)

    Chohan, Muhammad Omar; Sandoval, Daniel; Buchan, Andrew; Murray-Krezan, Cristina; Taylor, Christopher L

    2014-10-01

    Radiation exposure to patients and personnel remains a major concern in the practice of interventional radiology, with minimal literature available on exposure to the forehead and cranium. In this study, we measured cranial radiation exposure to the patient, operating interventional neuroradiologist, and circulating nurse during neuroangiographic procedures. We also report the effectiveness of wearing a 0.5 mm lead equivalent cap as protection against radiation scatter. 24 consecutive adult interventional neuroradiology procedures (six interventional, 18 diagnostic) were prospectively studied for cranial radiation exposures in the patient and personnel. Data were collected using electronic detectors and thermoluminescent dosimeters. Mean fluoroscopy time for diagnostic and interventional procedures was 8.48 (SD 2.79) min and 26.80 (SD 6.57) min, respectively. Mean radiation exposure to the operator's head was 0.08 mSv, as measured on the outside of the 0.5 mm lead equivalent protective headgear. This amounts to around 150 mSv/year, far exceeding the current deterministic threshold for the lens of the eye (ie, 20 mSv/year) in high volume centers performing up to five procedures a day. When compared with doses measured on the inside of the protective skullcap, there was a statistically significant reduction in the amount of radiation received by the operator's skull. Our study suggests that a modern neurointerventional suite is safe when equipped with proper protective shields and personal gear. However, cranial exposure is not completely eliminated with existing protective devices and the addition of a protective skullcap eliminates this exposure to both the operator and support staff. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  13. DNA damage caused by chronic transgenerational exposure to low dose gamma radiation in Medaka fish ( Oryzias latipes ).

    Science.gov (United States)

    Grygoryev, D; Moskalenko, O; Hinton, T G; Zimbrick, J D

    2013-09-01

    The effect of transgenerational exposure to low dose rate (2.4 and 21 mGy/day) gamma irradiation on the yield of DNA double-strand breaks and oxidized guanine (8-hydroxyguanine) has been studied in the muscle and liver tissue of a model organism, the Japanese medaka fish. We found the level of unrepaired 8-hydroxyguanine in muscle tissue increased nonlinearly over four generations and the pattern of this change depended on the radiation dose rate, suggesting that our treatment protocols initiated genomic instability and an adaptive response as the generations progressed. The yield of unrepaired double-strand breaks did not vary significantly among successive generations in muscle tissue in contrast to liver tissue in which it varied in a nonlinear manner. The 8-hydroxyguanine and DSB radiation yields were significantly higher at 2.4 mGy/day than at 21 mGy/day in both muscle and liver tissue in all generations. These data are consistent with the hypothesis of a threshold for radiation-induced activation of DNA repair systems below which tissue levels of DNA repair enzymes remain unchanged, leading to the accumulation of unrepaired damage at very low doses and dose rates.

  14. Predicted Radiation Exposure from Mining at Kvanefjeld

    DEFF Research Database (Denmark)

    Nielsen, Sven Poul; Roos, Per; Andersson, Kasper Grann

    Baseline surveys of gamma radiation and environmental radioactivity have been carried out by Greenland Minerals and Energy Ltd (GMEL) to show existing levels in the town of Narsaq and in the Kvanefjeld project area. Radiation levels in Narsaq are low but elevated in the project area due...... integrating dosimeters. The Technical University of Denmark (DTU) has reviewed the impact of Kvanefjeld operations on the future workforce to estimate radiation doses to individuals. Calculations were performed with conservative assumptions that reveal the annual radiation dose to workers to be between 1...... and 5 millisieverts (mSv). This range of annual doses is below the internationally accepted limits for occupational exposure of 20 mSv averaged over five consecutive years and 50 mSv in any single year. The radiation dose estimates calculated by DTU are consistent with actual measured radiation doses...

  15. SU-E-T-501: Normal Tissue Toxicities of Pulsed Low Dose Rate Radiotherapy and Conventional Radiotherapy: An in Vivo Total Body Irradiation Study

    Energy Technology Data Exchange (ETDEWEB)

    Cvetkovic, D; Zhang, P; Wang, B; Chen, L; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2014-06-01

    Purpose: Pulsed low dose rate radiotherapy (PLDR) is a re-irradiation technique for therapy of recurrent cancers. We have previously shown a significant difference in the weight and survival time between the mice treated with conventional radiotherapy (CRT) and PLDR using total body irradiation (TBI). The purpose of this study was to investigate the in vivo effects of PLDR on normal mouse tissues.Materials and Methods: Twenty two male BALB/c nude mice, 4 months of age, were randomly assigned into a PLDR group (n=10), a CRT group (n=10), and a non-irradiated control group (n=2). The Siemens Artiste accelerator with 6 MV photon beams was used. The mice received a total of 18Gy in 3 fractions with a 20day interval. The CRT group received the 6Gy dose continuously at a dose rate of 300 MU/min. The PLDR group was irradiated with 0.2Gyx20 pulses with a 3min interval between the pulses. The mice were weighed thrice weekly and sacrificed 2 weeks after the last treatment. Brain, heart, lung, liver, spleen, gastrointestinal, urinary and reproductive organs, and sternal bone marrow were removed, formalin-fixed, paraffin-embedded and stained with H and E. Morphological changes were observed under a microscope. Results: Histopathological examination revealed atrophy in several irradiated organs. The degree of atrophy was mild to moderate in the PLDR group, but severe in the CRT group. The most pronounced morphological abnormalities were in the immune and hematopoietic systems, namely spleen and bone marrow. Brain hemorrhage was seen in the CRT group, but not in the PLDR group. Conclusions: Our results showed that PLDR induced less toxicity in the normal mouse tissues than conventional radiotherapy for the same dose and regimen. Considering that PLDR produces equivalent tumor control as conventional radiotherapy, it would be a good modality for treatment of recurrent cancers.

  16. Treatment Outcome of Medium-Dose-Rate Intracavitary Brachytherapy for Carcinoma of the Uterine Cervix: Comparison With Low-Dose-Rate Intracavitary Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kaneyasu, Yuko, E-mail: kaneyasu@hiroshima-u.ac.jp [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Tokyo Women' s Medical University, Tokyo (Japan); Kita, Midori [Department of Radiation Oncology, Tokyo Women' s Medical University, Tokyo (Japan); Department of Clinical Radiology, Tokyo Metropolitan Tama Medical Center, Tokyo (Japan); Okawa, Tomohiko [Evaluation and Promotion Center, Utsunomiya Memorial Hospital, Tochigi (Japan); Maebayashi, Katsuya [Department of Radiation Oncology, Tokyo Women' s Medical University, Tokyo (Japan); Kohno, Mari [Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women' s Medical University Hospital, Tokyo (Japan); Sonoda, Tatsuo; Hirabayashi, Hisae [Department of Radiology, Tokyo Women' s Medical University Hospital, Tokyo (Japan); Nagata, Yasushi [Department of Radiation Oncology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima (Japan); Mitsuhashi, Norio [Department of Radiation Oncology, Tokyo Women' s Medical University, Tokyo (Japan)

    2012-09-01

    Purpose: To evaluate and compare the efficacy of medium-dose-rate (MDR) and low-dose-rate (LDR) intracavitary brachytherapy (ICBT) for uterine cervical cancer. Methods and Materials: We evaluated 419 patients with squamous cell carcinoma of the cervix who were treated by radical radiotherapy with curative intent at Tokyo Women's Medical University from 1969 to 1999. LDR was used from 1969 to 1986, and MDR has been used since July 1987. When compared with LDR, fraction dose was decreased and fraction size was increased (1 or 2 fractions) for MDR to make the total dose of MDR equal to that of LDR. In general, the patients received a total dose of 60 to 70 Gy at Point A with external beam radiotherapy combined with brachytherapy according to the International Federation of Gynecology and Obstetrics stage. In the LDR group, 32 patients had Stage I disease, 81 had Stage II, 182 had Stage III, and 29 had Stage IVA; in the MDR group, 9 patients had Stage I disease, 19 had Stage II, 55 had Stage III, and 12 had Stage IVA. Results: The 5-year overall survival rates for Stages I, II, III, and IVA in the LDR group were 78%, 72%, 55%, and 34%, respectively. In the MDR group, the 5-year overall survival rates were 100%, 68%, 52%, and 42%, respectively. No significant statistical differences were seen between the two groups. The actuarial rates of late complications Grade 2 or greater at 5 years for the rectum, bladder, and small intestine in the LDR group were 11.1%, 5.8%, and 2.0%, respectively. The rates for the MDR group were 11.7%, 4.2%, and 2.6%, respectively, all of which were without statistical differences. Conclusion: These data suggest that MDR ICBT is effective, useful, and equally as good as LDR ICBT in daytime (about 5 hours) treatments of patients with cervical cancer.

  17. Time-driven activity-based costing of low-dose-rate and high-dose-rate brachytherapy for low-risk prostate cancer.

    Science.gov (United States)

    Ilg, Annette M; Laviana, Aaron A; Kamrava, Mitchell; Veruttipong, Darlene; Steinberg, Michael; Park, Sang-June; Burke, Michael A; Niedzwiecki, Douglas; Kupelian, Patrick A; Saigal, Christopher

    Cost estimates through traditional hospital accounting systems are often arbitrary and ambiguous. We used time-driven activity-based costing (TDABC) to determine the true cost of low-dose-rate (LDR) and high-dose-rate (HDR) brachytherapy for prostate cancer and demonstrate opportunities for cost containment at an academic referral center. We implemented TDABC for patients treated with I-125, preplanned LDR and computed tomography based HDR brachytherapy with two implants from initial consultation through 12-month followup. We constructed detailed process maps for provision of both HDR and LDR. Personnel, space, equipment, and material costs of each step were identified and used to derive capacity cost rates, defined as price per minute. Each capacity cost rate was then multiplied by the relevant process time and products were summed to determine total cost of care. The calculated cost to deliver HDR was greater than LDR by $2,668.86 ($9,538 vs. $6,869). The first and second HDR treatment day cost $3,999.67 and $3,955.67, whereas LDR was delivered on one treatment day and cost $3,887.55. The greatest overall cost driver for both LDR and HDR was personnel at 65.6% ($4,506.82) and 67.0% ($6,387.27) of the total cost. After personnel costs, disposable materials contributed the second most for LDR ($1,920.66, 28.0%) and for HDR ($2,295.94, 24.0%). With TDABC, the true costs to deliver LDR and HDR from the health system perspective were derived. Analysis by physicians and hospital administrators regarding the cost of care afforded redesign opportunities including delivering HDR as one implant. Our work underscores the need to assess clinical outcomes to understand the true difference in value between these modalities. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  18. Image fusion analysis of volumetric changes after interstitial low-dose-rate iodine-125 irradiation of supratentorial low-grade gliomas.

    Science.gov (United States)

    Julow, Jeno; Major, Tibor; Mangel, László; Bajzik, Gábor; Viola, Arpad

    2007-04-01

    The aim of this study was to compare the volumes of tumor necrosis, reactive zone and edema with the three-dimensional dose distributions after brachytherapy treatments of gliomas. The investigation was performed an average of 14.2 months after low-dose-rate (125)I interstitial irradiation of 25 inoperable low-grade gliomas. The prescribed dose was 50-60 Gy to the tumor surface. Dose planning and image fusion were performed with the BrainLab-Target 1.19 software. In the CT/ MRI images, the "triple ring" (tumor necrosis, reactive ring and edema) developing after the interstitial irradiation of the brain tumors was examined. The images with the triple ring were fused with the planning images, and the isodose curves were superimposed on them. The volumes of the three regions were measured. The average dose at the necrosis border was determined from the isodose distribution. For quantitative assessment of the dose distributions, the dose nonuniformity ratio (DNR), homogeneity index (HI), coverage index (CI) and conformal index (COIN) were calculated. The relative volumes of the different parts of the triple ring after the interstitial irradiation compared to the reference dose volume were the following: necrosis, 40.9%, reactive zone, 47.1%, and edema, 367%. The tumor necrosis developed at 79.1 Gy on average. The average DNR, HI, CI and COIN were 0.45, 0.24, 0.94 and 0.57, respectively. The image fusion analysis of the volume of tumor necrosis, reactive ring and edema caused by interstitial irradiation and their correlation with the dose distribution provide valuable information for patient follow-up, treatment options, and effects and side effects of radio therapy.

  19. Tissues may adapt to radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-08-01

    French scientists discovered radioactivity and developed vaccination, so it is perhaps appropriate that a prominent French cancer specialist should be promoting the idea of a radiation vaccination effect - or radiation adaptation, as he prefers to call it. Raymond Latarjet, of the Institut Curie in Paris, maintains that recent studies at the gene level are showing evidence that with low doses of radiation, there is time for a cell repair mechanism to take effect, and that this seems to provide some protection against subsequent exposure to high doses. He cited experiments in his laboratory in which exposure to a dose of 4 Gy (400 rad) had, predictably, produced a large number of gene mutations in a specimen, but the number of mutations was less than half that number in a specimen that had been exposed to a dose of 0.02 Gy some six hours before exposure to the 4 Gy.

  20. Low Dose Rate Ionizing Radiation Response of Bipolar Transistors%双极晶体管的低剂量率电离辐射效应

    Institute of Scientific and Technical Information of China (English)

    张华林; 陆妩; 任迪远; 郭旗; 余学锋; 何承发; 艾尔肯; 崔帅

    2004-01-01

    通过对 npn 管和 pnp 管进行不同剂量率的电离辐射实验,研究了双极晶体管的低剂量率辐射效应.结果表明,双极晶体管在低剂量率辐照下电流增益下降更为显著,这是由于低剂量率辐照在氧化层中感生了更多的净氧化物正电荷浓度,致使低剂量率下过量基极电流明显增大.而辐照后npn管比pnp管具有更大的有效表面复合面积,致使前者比后者有更大的表面复合电流,从而导致了在各种剂量率辐照下,npn管比pnp管对电离辐射都更为敏感.

  1. DOE occupational radiation exposure 1996 report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The goal of the US Department of Energy (DOE) is to conduct its radiological operations to ensure the health and safety of all DOE employees including contractors and subcontractors. The DOE strives to maintain radiation exposures to its workers below administrative control levels and DOE limits and to further reduce these exposures and releases to levels that are ``As Low As Reasonably Achievable`` (ALARA). The DOE Occupational Radiation Exposure Report, 1996 provides summary and analysis of the occupational radiation exposure received by individuals associated with DOE activities. The DOE mission includes stewardship of the nuclear weapons stockpile and the associated facilities, environmental restoration of DOE and precursor agency sites, and energy research. Collective exposure at DOE has declined by 80% over the past decade due to a cessation in opportunities for exposure during the transition in DOE mission from weapons production to cleanup, deactivation and decommissioning, and changes in reporting requirements and dose calculation methodology. In 1996, the collective dose decreased by 10% from the 1995 value due to decreased doses at five of the seven highest-dose DOE sites. For 1996, these sites attributed the reduction in collective dose to the completion of several decontamination and decommissioning projects, reduced spent fuel storage activities, and effective ALARA practices. This report is intended to be a valuable tool for managers in their management of radiological safety programs and commitment of resources.

  2. DOE occupational radiation exposure 1996 report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The goal of the US Department of Energy (DOE) is to conduct its radiological operations to ensure the health and safety of all DOE employees including contractors and subcontractors. The DOE strives to maintain radiation exposures to its workers below administrative control levels and DOE limits and to further reduce these exposures and releases to levels that are ``As Low As Reasonably Achievable`` (ALARA). The DOE Occupational Radiation Exposure Report, 1996 provides summary and analysis of the occupational radiation exposure received by individuals associated with DOE activities. The DOE mission includes stewardship of the nuclear weapons stockpile and the associated facilities, environmental restoration of DOE and precursor agency sites, and energy research. Collective exposure at DOE has declined by 80% over the past decade due to a cessation in opportunities for exposure during the transition in DOE mission from weapons production to cleanup, deactivation and decommissioning, and changes in reporting requirements and dose calculation methodology. In 1996, the collective dose decreased by 10% from the 1995 value due to decreased doses at five of the seven highest-dose DOE sites. For 1996, these sites attributed the reduction in collective dose to the completion of several decontamination and decommissioning projects, reduced spent fuel storage activities, and effective ALARA practices. This report is intended to be a valuable tool for managers in their management of radiological safety programs and commitment of resources.

  3. Exposure from residual radiation after synchrotron shutdown

    Energy Technology Data Exchange (ETDEWEB)

    Moyers, M.F. [Proton Therapy, Inc., Colton, CA 92324 (United States)], E-mail: mfmoyers@roadrunner.com; Lesyna, D.A. [Optivus Proton Therapy, San Bernardino, CA 92408 (United States)

    2009-02-15

    Personnel exposure from residual radiation present after an accelerator is shutdown for preventative or corrective maintenance is an important aspect that governs the manner in which a light ion facility can be used. This radiation is not only a safety issue for maintenance personnel but also can affect the patient throughput of the facility. Measurements were made with survey instruments around the synchrotron accelerator at the Loma Linda University Proton Treatment Facility and personnel dosimetry records of maintenance staff were reviewed. Results showed that the residual radiation in this facility design is very low, does not significantly impact maintenance staff safety, and has placed no restrictions on patient throughput.

  4. Minimal percentage of dose received by 90% of the urethra (%UD90 is the most significant predictor of PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy for prostate cancer

    Directory of Open Access Journals (Sweden)

    Tanaka Nobumichi

    2012-09-01

    Full Text Available Abstract Background To clarify the significant clinicopathological and postdosimetric parameters to predict PSA bounce in patients who underwent low-dose-rate brachytherapy (LDR-brachytherapy for prostate cancer. Methods We studied 200 consecutive patients who received LDR-brachytherapy between July 2004 and November 2008. Of them, 137 patients did not receive neoadjuvant or adjuvant androgen deprivation therapy. One hundred and forty-two patients were treated with LDR-brachytherapy alone, and 58 were treated with LDR-brachytherapy in combination with external beam radiation therapy. The cut-off value of PSA bounce was 0.1 ng/mL. The incidence, time, height, and duration of PSA bounce were investigated. Clinicopathological and postdosimetric parameters were evaluated to elucidate independent factors to predict PSA bounce in hormone-naïve patients who underwent LDR-brachytherapy alone. Results Fifty patients (25% showed PSA bounce and 10 patients (5% showed PSA failure. The median time, height, and duration of PSA bounce were 17 months, 0.29 ng/mL, and 7.0 months, respectively. In 103 hormone-naïve patients treated with LDR-brachytherapy alone, and univariate Cox proportional regression hazard model indicated that age and minimal percentage of the dose received by 30% and 90% of the urethra were independent predictors of PSA bounce. With a multivariate Cox proportional regression hazard model, minimal percentage of the dose received by 90% of the urethra was the most significant parameter of PSA bounce. Conclusions Minimal percentage of the dose received by 90% of the urethra was the most significant predictor of PSA bounce in hormone-naïve patients treated with LDR-brachytherapy alone.

  5. A translatable predictor of human radiation exposure.

    Directory of Open Access Journals (Sweden)

    Joseph Lucas

    Full Text Available Terrorism using radiological dirty bombs or improvised nuclear devices is recognized as a major threat to both public health and national security. In the event of a radiological or nuclear disaster, rapid and accurate biodosimetry of thousands of potentially affected individuals will be essential for effective medical management to occur. Currently, health care providers lack an accurate, high-throughput biodosimetric assay which is suitable for the triage of large numbers of radiation injury victims. Here, we describe the development of a biodosimetric assay based on the analysis of irradiated mice, ex vivo-irradiated human peripheral blood (PB and humans treated with total body irradiation (TBI. Interestingly, a gene expression profile developed via analysis of murine PB radiation response alone was inaccurate in predicting human radiation injury. In contrast, generation of a gene expression profile which incorporated data from ex vivo irradiated human PB and human TBI patients yielded an 18-gene radiation classifier which was highly accurate at predicting human radiation status and discriminating medically relevant radiation dose levels in human samples. Although the patient population was relatively small, the accuracy of this classifier in discriminating radiation dose levels in human TBI patients was not substantially confounded by gender, diagnosis or prior exposure to chemotherapy. We have further incorporated genes from this human radiation signature into a rapid and high-throughput chemical ligation-dependent probe amplification assay (CLPA which was able to discriminate radiation dose levels in a pilot study of ex vivo irradiated human blood and samples from human TBI patients. Our results illustrate the potential for translation of a human genetic signature for the diagnosis of human radiation exposure and suggest the basis for further testing of CLPA as a candidate biodosimetric assay.

  6. Studies about space radiation promote new fields in radiation biology.

    Science.gov (United States)

    Ohnishi, Takeo; Takahashi, Akihisa; Ohnishi, Ken

    2002-12-01

    Astronauts are constantly exposed to space radiation of various types of energy with a low dose-rate during long-term stays in space. Therefore, it is important to determine correctly the biological effects of space radiation on human health. Studies about biological the effects at a low dose and a low dose-rate include various aspects of microbeams, bystander effects, radioadaptive responses and hormesis which are important fields in radiation biology. In addition, space radiations contain high linear energy transfer (LET) particles. In particular, neutrons may cause reverse effectiveness at a low dose-rate in comparison to ionizing radiation. We are also interested in p53-centered signal transduction pathways involved in the cell cycle, DNA repair and apoptosis induced by space radiations. We must also study whether the relative biological effectiveness (RBE) of space radiation is affected by microgravity which is another typical component in space. To confirm this, we must prepare centrifuge systems in an International Space Station (ISS). In addition, we must prepare many types of equipment for space experiments in an ISS, because we cannot use conventional equipment from our laboratories. Furthermore, the research for space radiation might give us valuable information about the birth and evolution of life on the Earth. We can also realize the importance of preventing the ozone layer from depletion by the use of exposure equipment to sunlight in an ISS. For these reasons, we desire to educate space researchers of the next generation based on the consideration of the preservation of the Earth from research about space radiation.

  7. DOE 2012 Occupational Radiation Exposure October 2013

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-02-02

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. As an indicator of the overall amount of radiation dose received during the conduct of operations at DOE, the report includes information on collective total effective dose (TED). The TED is comprised of the effective dose (ED) from external sources, which includes neutron and photon radiation, and the internal committed effective dose (CED), which results from the intake of radioactive material into the body. The collective ED from photon exposure decreased by 23% between 2011 and 2012, while the neutron dose increased by 5%. The internal dose components of the collective TED decreased by 7%. Over the past 5-year period, 99.99% of the individuals receiving measurable TED have received doses below the 2 roentgen equivalent in man (rems) (20 millisievert [mSv]) TED administrative control level (ACL), which is well below the DOE regulatory limit of 5 rems (50 mSv) TED annually. The

  8. SU-E-T-620: Planning and Dosimetry for Pulsed Low Dose Rate RT for Recurrent Lung, Spine, GYN and Head and Neck Cancers

    Energy Technology Data Exchange (ETDEWEB)

    Tong, X; Luo, F; Liu, Y; Zhang, W; Xu, Q; Zhang, T; Li, J [3rd Affiliated Hospital of Qiqihar Medical University, Qiqihar (China); Chen, L; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2015-06-15

    Purpose: Extensive in vitro and in vivo studies have shown that pulsed low dose rate (PLDR) radiotherapy has potential to provide significant local tumor control and to reduce normal tissue toxicities. This work investigated the planning and dosimetry of PLDR re-irradiation for recurrent cancers. Methods: We analyzed the treatment plans and dosimetry for 13 recurrent patients who were treated with the PLDR technique in this study. All cases were planned with the 3DCRT technique with optimal beam angle selection. The treatment was performed on a Siemens accelerator using 6MV beams. The target volume ranged between 161 and 703cc. The previous RT dose was 40–60Gy while the re-irradiation dose was 16–60Gy. The interval between previous RT and re-irradiation was 13–336 months, and the follow-up time was up to 27months. The total prescription dose was administered in 2Gy/day fractions with the daily dose delivered in 10 sub-fractions (pulses) of 20cGy with a 3min interval between the pulses to achieve an effective dose rate of 6.7cGy/min. Results: The clinical outcome was analyzed based on the treatment plans. All pulses were kept with Dmax<40cGy. The PLDR treatments were effective (CR: 3 patients, PR: 10 patients). The acute and late toxicities were all acceptable (generally grade II or under). Two patients died three months after the PLDR re-irradiation, one due to massive cerebral infarction and the other due to acute cardiac failure. All others survived more than 8 months. Five patients showed good conditions at the last follow-up. Among them two recurrent lung cancer patients had survived 23 months and one nasopharyngeal cancer patient had survived 27 months. Conclusion: The PLDR technique was effective for the palliative treatment of head and neck, lung, spine and GYN cancers. Further phase II and III studies are warranted to quantify the efficacy of PLDR for recurrent cancers.

  9. Long-Term Efficacy and Toxicity of Low-Dose-Rate {sup 125}I Prostate Brachytherapy as Monotherapy in Low-, Intermediate-, and High-Risk Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kittel, Jeffrey A.; Reddy, Chandana A.; Smith, Kristin L.; Stephans, Kevin L.; Tendulkar, Rahul D. [Department of Radiation Oncology, Cleveland Clinic Taussig Cancer Institute, Cleveland, Ohio (United States); Ulchaker, James; Angermeier, Kenneth; Campbell, Steven; Stephenson, Andrew; Klein, Eric A. [Department of Urology, Cleveland Clinic Glickman Urological and Kidney Institute, Cleveland, Ohio (United States); Wilkinson, D. Allan [Department of Radiation Oncology, Cleveland Clinic Taussig Cancer Institute, Cleveland, Ohio (United States); Ciezki, Jay P., E-mail: ciezkij@ccf.org [Department of Radiation Oncology, Cleveland Clinic Taussig Cancer Institute, Cleveland, Ohio (United States)

    2015-07-15

    Purpose/Objectives: To report long-term efficacy and toxicity for a single-institution cohort of patients treated with low-dose-rate prostate brachytherapy permanent implant (PI) monotherapy. Methods and Materials: From 1996 to 2007, 1989 patients with low-risk (61.3%), intermediate-risk (29.8%), high-intermediate-risk (4.5%), and high-risk prostate cancer (4.4%) were treated with PI and followed up prospectively in a registry. All patients were treated with {sup 125}I monotherapy to 144 Gy. Late toxicity was coded retrospectively according to a modified Common Terminology Criteria for Adverse Events 4.0 scale. The rates of biochemical relapse-free survival (bRFS), distant metastasis-free survival (DMFS), overall survival (OS), and prostate cancer–specific mortality (PCSM) were calculated. We identified factors associated with late grade ≥3 genitourinary (GU) and gastrointestinal (GI) toxicity, bRFS, DMFS, OS, PCSM, and incontinence. Results: The median age of the patients was 67 years, and the median overall and prostate-specific antigen follow-up times were 6.8 years and 5.8 years, respectively. The overall 5-year rates for bRFS, DMFS, OS, and PCSM were 91.9%, 97.8%, 93.7%, and 0.71%, respectively. The 10-year rates were 81.5%, 91.5%, 76.1%, and 2.5%, respectively. The overall rates of late grade ≥3 GU and GI toxicity were 7.6% and 0.8%, respectively. On multivariable analysis, age and prostate length were significantly associated with increased risk of late grade ≥3 GU toxicity. The risk of incontinence was highly correlated with both pre-PI and post-PI transurethral resection of the prostate. Conclusions: Prostate brachytherapy as monotherapy is an effective treatment for low-risk and low-intermediate-risk prostate cancer and appears promising as a treatment for high-intermediate-risk and high-risk prostate cancer. Significant long-term toxicities are rare when brachytherapy is performed as monotherapy.

  10. The investigation of prostatic calcifications using μ-PIXE analysis and their dosimetric effect in low dose rate brachytherapy treatments using Geant4

    Science.gov (United States)

    Pope, D. J.; Cutajar, D. L.; George, S. P.; Guatelli, S.; Bucci, J. A.; Enari, K. E.; Miller, S.; Siegele, R.; Rosenfeld, A. B.

    2015-06-01

    Low dose rate brachytherapy is a widely used modality for the treatment of prostate cancer. Most clinical treatment planning systems currently in use approximate all tissue to water, neglecting the existence of inhomogeneities, such as calcifications. The presence of prostatic calcifications may perturb the dose due to the higher photoelectric effect cross section in comparison to water. This study quantitatively evaluates the effect of prostatic calcifications on the dosimetric outcome of brachytherapy treatments by means of Monte Carlo simulations and its potential clinical consequences. Four pathological calcification samples were characterised with micro-particle induced x-ray emission (μ-PIXE) to determine their heavy elemental composition. Calcium, phosphorus and zinc were found to be the predominant heavy elements in the calcification composition. Four clinical patient brachytherapy treatments were modelled using Geant4 based Monte Carlo simulations, in terms of the distribution of brachytherapy seeds and calcifications in the prostate. Dose reductions were observed to be up to 30% locally to the calcification boundary, calcification size dependent. Single large calcifications and closely placed calculi caused local dose reductions of between 30-60%. Individual calculi smaller than 0.5 mm in diameter showed minimal dosimetric impact, however, the effects of small or diffuse calcifications within the prostatic tissue could not be determined using the methods employed in the study. The simulation study showed a varying reduction on common dosimetric parameters. D90 showed a reduction of 2-5%, regardless of calcification surface area and volume. The parameters V100, V150 and V200 were also reduced by as much as 3% and on average by 1%. These reductions were also found to relate to the surface area and volume of calcifications, which may have a significant dosimetric impact on brachytherapy treatment, however, such impacts depend strongly on specific factors

  11. Cosmic radiation exposure and persistent cognitive dysfunction

    Science.gov (United States)

    Parihar, Vipan K.; Allen, Barrett D.; Caressi, Chongshan; Kwok, Stephanie; Chu, Esther; Tran, Katherine K.; Chmielewski, Nicole N.; Giedzinski, Erich; Acharya, Munjal M.; Britten, Richard A.; Baulch, Janet E.; Limoli, Charles L.

    2016-01-01

    The Mars mission will result in an inevitable exposure to cosmic radiation that has been shown to cause cognitive impairments in rodent models, and possibly in astronauts engaged in deep space travel. Of particular concern is the potential for cosmic radiation exposure to compromise critical decision making during normal operations or under emergency conditions in deep space. Rodents exposed to cosmic radiation exhibit persistent hippocampal and cortical based performance decrements using six independent behavioral tasks administered between separate cohorts 12 and 24 weeks after irradiation. Radiation-induced impairments in spatial, episodic and recognition memory were temporally coincident with deficits in executive function and reduced rates of fear extinction and elevated anxiety. Irradiation caused significant reductions in dendritic complexity, spine density and altered spine morphology along medial prefrontal cortical neurons known to mediate neurotransmission interrogated by our behavioral tasks. Cosmic radiation also disrupted synaptic integrity and increased neuroinflammation that persisted more than 6 months after exposure. Behavioral deficits for individual animals correlated significantly with reduced spine density and increased synaptic puncta, providing quantitative measures of risk for developing cognitive impairment. Our data provide additional evidence that deep space travel poses a real and unique threat to the integrity of neural circuits in the brain. PMID:27721383

  12. Cosmic radiation exposure and persistent cognitive dysfunction.

    Science.gov (United States)

    Parihar, Vipan K; Allen, Barrett D; Caressi, Chongshan; Kwok, Stephanie; Chu, Esther; Tran, Katherine K; Chmielewski, Nicole N; Giedzinski, Erich; Acharya, Munjal M; Britten, Richard A; Baulch, Janet E; Limoli, Charles L

    2016-10-10

    The Mars mission will result in an inevitable exposure to cosmic radiation that has been shown to cause cognitive impairments in rodent models, and possibly in astronauts engaged in deep space travel. Of particular concern is the potential for cosmic radiation exposure to compromise critical decision making during normal operations or under emergency conditions in deep space. Rodents exposed to cosmic radiation exhibit persistent hippocampal and cortical based performance decrements using six independent behavioral tasks administered between separate cohorts 12 and 24 weeks after irradiation. Radiation-induced impairments in spatial, episodic and recognition memory were temporally coincident with deficits in executive function and reduced rates of fear extinction and elevated anxiety. Irradiation caused significant reductions in dendritic complexity, spine density and altered spine morphology along medial prefrontal cortical neurons known to mediate neurotransmission interrogated by our behavioral tasks. Cosmic radiation also disrupted synaptic integrity and increased neuroinflammation that persisted more than 6 months after exposure. Behavioral deficits for individual animals correlated significantly with reduced spine density and increased synaptic puncta, providing quantitative measures of risk for developing cognitive impairment. Our data provide additional evidence that deep space travel poses a real and unique threat to the integrity of neural circuits in the brain.

  13. Radiation exposure in CT-guided interventions

    Energy Technology Data Exchange (ETDEWEB)

    Kloeckner, Roman, E-mail: Roman.Kloeckner@unimedizin-mainz.de [Department of Diagnostic and Interventional Radiology, Johannes Gutenberg-University, Langenbeckstraße 1, 55131 Mainz (Germany); Santos, Daniel Pinto dos; Schneider, Jens [Department of Diagnostic and Interventional Radiology, Johannes Gutenberg-University, Langenbeckstraße 1, 55131 Mainz (Germany); Kara, Levent [Department of Radiology, Inselspital Bern, Freiburgstraße 18, 3010 Bern (Switzerland); Dueber, Christoph; Pitton, Michael B. [Department of Diagnostic and Interventional Radiology, Johannes Gutenberg-University, Langenbeckstraße 1, 55131 Mainz (Germany)

    2013-12-01

    Purpose: To investigate radiation exposure in computed tomography (CT)-guided interventions, to establish reference levels for exposure, and to discuss strategies for dose reduction. Materials and methods: We analyzed 1576 consecutive CT-guided procedures in 1284 patients performed over 4.5 years, including drainage placements; biopsies of different organs; radiofrequency and microwave ablations (RFA/MWA) of liver, bone, and lung tumors; pain blockages, and vertebroplasties. Data were analyzed with respect to scanner settings, overall radiation doses, and individual doses of planning CT series, CT intervention, and control CT series. Results: Eighy-five percent of the total radiation dose was applied during the pre- and post-interventional CT series, leaving only 15% applied by the CT-guided intervention itself. Single slice acquisition was associated with lower doses than continuous CT-fluoroscopy (37 mGy cm vs. 153 mGy cm, p < 0.001). The third quartile of radiation doses varied considerably for different interventions. The highest doses were observed in complex interventions like RFA/MWA of the liver, followed by vertebroplasty and RFA/MWA of the lung. Conclusions: This paper suggests preliminary reference levels for various intervention types and discusses strategies for dose reduction. A multicenter registry of radiation exposure including a broader spectrum of scanners and intervention types is needed to develop definitive reference levels.

  14. Radiation exposure reduction in APR1400

    Energy Technology Data Exchange (ETDEWEB)

    Bae, C. J.; Hwang, H. R. [Korea Power Engineering Company, Inc., Yongin (Korea, Republic of); Matteson, D. M. [Westinghouse Electric Company, Pittsburgh (United States)

    2003-06-15

    The primary contributors to the total occupational radiation exposure in operating nuclear power plants are operation and maintenance activities during refueling outages. The Advanced Power Reactor 1400 (APR1400) includes a number of design improvements and plans to utilize advanced maintenance methods and robotics to minimize the annual collective dose. The major radiation exposure reduction features implemented in APR1400 are a permanent refueling pool seal, quick opening transfer tube blind flange, improved hydrogen peroxide injection at shutdown, improved permanent steam generator work platforms, and more effective temporary shielding. The estimated average annual occupational radiation exposure for APR1400 based on the reference plant experience and an engineering judgment is determined to be in the order of 0.4 man-Sv, which is well within the design goal of 1 man-Sv. The basis of this average annual occupational radiation exposure estimation is an eighteen (18) month fuel cycle with maintenance performed to steam generators and reactor coolant pumps during refueling outage. The outage duration is assumed to be 28 days. The outage work is to be performed on a 24 hour per day basis, seven (7) days a week with overlapping twelve (12) hour work shifts. The occupational radiation exposure for APR 1400 is also determined by an alternate method which consists of estimating radiation exposures expected for the major activities during the refueling outage. The major outage activities that cause the majority of the total radiation exposure during refueling outage such as fuel handling, reactor coolant pump maintenance, steam generator inspection and maintenance, reactor vessel head area maintenance, decontamination, and ICI and instrumentation maintenance activities are evaluated at a task level. The calculated value using this method is in close agreement with the value of 0.4 man-Sv, that has been determined based on the experience and engineering judgement

  15. Radiation exposure mitigation through food

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Yoshikazu; Yukawa, Masae; Watanabe, Yoshito; Shiraishi, Kunio; Muramatsu, Yasuyuki; Uchida, Shigeo [National Inst. of Radiological Sciences, Chiba (Japan); Watabe, Teruhisa; Miyazaki, Taeko [National Inst. of Radiological Sciences, Hitachinaka, Ibaraki (Japan). Lab. for Radioecology

    2001-12-01

    {sup 137}CsCl{sub 2} was incorporated into plants (tomyao and broccoli) and these homogenized solutions were administered to rats. The whole-body retention was determined with an Armac counter. The whole body retention patterns of {sup 137}Cs incorporated into the plants were not significantly different from that of the {sup 137}CsCl{sub 2} solution. Chitosan is derived from chitin, which is a cellulose-like biopolymer distributed widely in nature, especially in crustaceans, insects, fungi and yeast. The present study was to investigate whether chitosan can be applied to animal and human bodies in order to reduce the bioavailability of radio-iron and -zinc in food. Chitosan inhibits dietary iron absorption only when rats eat on iron-deficient diet. The effectiveness of phytate (myo-inositol 1,2,3,4,5,6-hexakis dihydrogen phosphate) and chitosan in reducing the bioavailability of radio-zinc depend on the concentration of phytate and chitosan. Recently, the share of imported foods increased ca. 40% of Japanese total food consumption. Radioactivities in imported foods must be checked from the viewpoints of internal radiation for Japanese subjects. Concentrations of {sup 232}Th and {sup 238}U in some imported mineral waters were higher than domestic waters. However, internal doses of portable waters are negligible. Individual foodstuffs in major food groups (fish and shellfish, meats, mushrooms, root vegetables and so on), which contributed to some radionuclide intakes in Japanese, were also analyzed to clarify the critical pathway in Japanese subjects. (author)

  16. DOE occupational radiation exposure 2004 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2004-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Performance Assessment (EH-3) publishes the annual DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE and DOE contractor managers and workers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE to make the report most useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, and subcontractors, as well as members of the public. DOE is defined to include the National Nuclear Security Administration sites. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  17. DOE occupational radiation exposure 2003 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2003-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Performance Assessment (EH-3) publishes the annual DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE and DOE contractor managers and workers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE to make the report most useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and members of the public. DOE is defined to include the National Nuclear Security Administration sites. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  18. DOE occupational radiation exposure 1998 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1998-12-31

    The U.S. Department of Energy (DOE) Office of Environment, Safety and Health with support from Environment Safety and Health Technical Information Services publishes the DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE/DOE contractor managers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE and hope we have succeeded in making the report more useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and visitors. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  19. DOE occupational radiation exposure 2002 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Performance Assessment (EH-3) publishes the annual DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE and DOE contractor managers and workers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE to make the report most useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and members of the public. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  20. DOE occupational radiation exposure 1999 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1999-12-31

    The U.S. Department of Energy (DOE) Office of Safety and Health publishes the annual DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE and DOE contractor managers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE and hope we have succeeded in making the report more useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and visitors. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  1. DOE occupational radiation exposure 1997 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1997-12-31

    The U.S. Department of Energy (DOE) Office of Environment, Safety and Health publishes the DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE/DOE contractor managers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE and hope we have succeeded in making the report more useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and visitors. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  2. DOE occupational radiation exposure 2002 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2002-12-31

    The U.S. Department of Energy (DOE) Office of Corporate Performance Assessment (EH-3) publishes the annual DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE and DOE contractor managers and workers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE to make the report most useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and members of the public. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  3. DOE occupational radiation exposure 1997 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1997-12-31

    The U.S. Department of Energy (DOE) Office of Environment, Safety and Health publishes the DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE/DOE contractor managers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE and hope we have succeeded in making the report more useful. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and visitors. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  4. DOE occupational radiation exposure 2000 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2000-12-31

    The U.S. Department of Energy (DOE) Office of Safety and Health publishes the annual DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE and DOE contractor managers in managing radiological safety programs and to assist them in prioritizing resources. We appreciate the efforts and contributions from the various stakeholders within and outside DOE in making this report most useful to them. This report includes occupational radiation exposure information for all monitored DOE employees, contractors, subcontractors, and visitors. The exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  5. DOE occupational radiation exposure 1996 report

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1996-12-31

    The U.S. Department of Energy (DOE) Office of Environment, Safety and Health publishes the DOE Occupational Radiation Exposure Report. This report is intended to be a valuable tool for DOE/DOE contractor managers in their management of radiological safety programs and to assist them in the prioritization of resources. We appreciate the efforts and contributions from the various stakeholders within and outside the DOE and hope we have succeeded in making the report more useful. This report includes occupational radiation exposure information for all DOE employees, contractors, subcontractors, and visitors. The exposure information is analyzed in terms of collective data, dose to individuals, and dose by site. For the purposes of examining trends, data for the past 5 years are included in the analysis.

  6. Space Radiation and Human Exposures, A Primer.

    Science.gov (United States)

    Nelson, Gregory A

    2016-04-01

    The space radiation environment is a complex field comprised primarily of charged particles spanning energies over many orders of magnitude. The principal sources of these particles are galactic cosmic rays, the Sun and the trapped radiation belts around the earth. Superimposed on a steady influx of cosmic rays and a steady outward flux of low-energy solar wind are short-term ejections of higher energy particles from the Sun and an 11-year variation of solar luminosity that modulates cosmic ray intensity. Human health risks are estimated from models of the radiation environment for various mission scenarios, the shielding of associated vehicles and the human body itself. Transport models are used to propagate the ambient radiation fields through realistic shielding levels and materials to yield radiation field models inside spacecraft. Then, informed by radiobiological experiments and epidemiology studies, estimates are made for various outcome measures associated with impairments of biological processes, losses of function or mortality. Cancer-associated risks have been formulated in a probabilistic model while management of non-cancer risks are based on permissible exposure limits. This article focuses on the various components of the space radiation environment and the human exposures that it creates.

  7. Leukemia risk associated with chronic external exposure to ionizing radiation in a French cohort of nuclear workers.

    Science.gov (United States)

    Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

    2012-11-01

    Leukemia is one of the earliest cancer effects observed after acute exposure to relatively high doses of ionizing radiation. Leukemia mortality after external exposure at low doses and low-dose rates has been investigated at the French Atomic Energy Commission (CEA) and Nuclear Fuel Company (AREVA NC) after an additional follow-up of 10 years. The cohort included radiation-monitored workers employed for at least one year during 1950-1994 at CEA or AREVA NC and followed during 1968-2004. Association between external exposure and leukemia mortality was estimated with excess relative risk (ERR) models and time-dependent modifying factors were investigated with time windows. The cohort included 36,769 workers, followed for an average of 28 years, among whom 73 leukemia deaths occurred. Among the workers with a positive recorded dose, the mean cumulative external dose was 21.7 mSv. Results under a 2-year lag assumption suggested that the risk of leukemia (except chronic lymphatic leukemia) increased significantly by 8% per 10 mSv. The magnitude of the association for myeloid leukemia was larger. The higher ERR/Sv for doses received 2-14 years earlier suggest that time since exposure modifies the effect. The ERR/Sv also appeared higher for doses received at exposure rates ≥20 mSv per year. These results are consistent with those found in other studies of nuclear workers. However, confidence intervals are still wide. Further analyses should be conducted in pooled cohorts of nuclear workers.

  8. Exposure assessment of aluminum arc welding radiation.

    Science.gov (United States)

    Peng, Chiung-yu; Lan, Cheng-hang; Juang, Yow-jer; Tsao, Ta-ho; Dai, Yu-tung; Liu, Hung-hsin; Chen, Chiou-jong

    2007-10-01

    The purpose of this study is to evaluate the non-ionizing radiation (NIR) exposure, especially optical radiation levels, and potential health hazard from aluminum arc welding processes based on the American Conference of Governmental Industrial Hygienists (ACGIH) method. The irradiance from the optical radiation emissions can be calculated with various biological effective parameters [i.e., S(lambda), B(lambda), R(lambda)] for NIR hazard assessments. The aluminum arc welding processing scatters bright light with NIR emission including ultraviolet radiation (UVR), visible, and infrared spectra. The UVR effective irradiance (Eeff) has a mean value of 1,100 microW cm at 100 cm distance from the arc spot. The maximum allowance time (tmax) is 2.79 s according to the ACGIH guideline. Blue-light hazard effective irradiance (EBlue) has a mean value of 1840 microW cm (300-700 nm) at 100 cm with a tmax of 5.45 s exposure allowance. Retinal thermal hazard effective calculation shows mean values of 320 mW cm(-2) sr(-1) and 25.4 mW (cm-2) (380-875 nm) for LRetina (spectral radiance) and ERetina (spectral irradiance), respectively. From this study, the NIR measurement from welding optical radiation emissions has been established to evaluate separate types of hazards to the eye and skin simultaneously. The NIR exposure assessment can be applied to other optical emissions from industrial sources. The data from welding assessment strongly suggest employees involved in aluminum welding processing must be fitted with appropriate personal protection devices such as masks and gloves to prevent serious injuries of the skin and eyes upon intense optical exposure.

  9. Modeling Impaired Hippocampal Neurogenesis after Radiation Exposure.

    Science.gov (United States)

    Cacao, Eliedonna; Cucinotta, Francis A

    2016-03-01

    Radiation impairment of neurogenesis in the hippocampal dentate gyrus is one of several factors associated with cognitive detriments after treatment of brain cancers in children and adults with radiation therapy. Mouse models have been used to study radiation-induced changes in neurogenesis, however the models are limited in the number of doses, dose fractions, age and time after exposure conditions that have been studied. The purpose of this study is to develop a novel predictive mathematical model of radiation-induced changes to neurogenesis using a system of nonlinear ordinary differential equations (ODEs) to represent the time, age and dose-dependent changes to several cell populations participating in neurogenesis as reported in mouse experiments exposed to low-LET radiation. We considered four compartments to model hippocampal neurogenesis and, consequently, the effects of radiation treatment in altering neurogenesis: (1) neural stem cells (NSCs), (2) neuronal progenitor cells or neuroblasts (NB), (3) immature neurons (ImN) and (4) glioblasts (GB). Because neurogenesis is decreasing with increasing mouse age, a description of the age-related dynamics of hippocampal neurogenesis is considered in the model, which is shown to be an important factor in comparisons to experimental data. A key feature of the model is the description of negative feedback regulation on early and late neuronal proliferation after radiation exposure. The model is augmented with parametric descriptions of the dose and time after irradiation dependences of activation of microglial cells and a possible shift of NSC proliferation from neurogenesis to gliogenesis reported at higher doses (∼10 Gy). Predictions for dose-fractionation regimes and for different mouse ages, and prospects for future work are then discussed.

  10. Quantitative Metabolomic Analysis of Urinary Citrulline and Calcitroic Acid in Mice after Exposure to Various Types of Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    Maryam Goudarzi

    2016-05-01

    Full Text Available With the safety of existing nuclear power plants being brought into question after the Fukushima disaster and the increased level of concern over terrorism-sponsored use of improvised nuclear devices, it is more crucial to develop well-defined radiation injury markers in easily accessible biofluids to help emergency-responders with injury assessment during patient triage. Here, we focused on utilizing ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS to identify and quantitate the unique changes in the urinary excretion of two metabolite markers, calcitroic acid and citrulline, in mice induced by different forms of irradiation; X-ray irradiation at a low dose rate (LDR of 3.0 mGy/min and a high dose rate (HDR of 1.1 Gy/min, and internal exposure to Cesium-137 (137Cs and Strontium-90 (90Sr. The multiple reaction monitoring analysis showed that, while exposure to 137Cs and 90Sr induced a statistically significant and persistent decrease, similar doses of X-ray beam at the HDR had the opposite effect, and the LDR had no effect on the urinary levels of these two metabolites. This suggests that the source of exposure and the dose rate strongly modulate the in vivo metabolomic injury responses, which may have utility in clinical biodosimetry assays for the assessment of exposure in an affected population. This study complements our previous investigations into the metabolomic profile of urine from mice internally exposed to 90Sr and 137Cs and to X-ray beam radiation.

  11. Wireless Phones Electromagnetic Field Radiation Exposure Assessment

    OpenAIRE

    A. D. Usman; W. F.W. Ahmad; M. Z. A. A. Kadir; M. Mokhtar

    2009-01-01

    Problem statement: Inadequate knowledge of electromagnetic field emitted by mobile phones and increased usage at close proximity, created a lot of skepticism and speculations among end users on its safety or otherwise. Approach: In this study, near field electromagnetic field radiation measurements were conducted on different brand of mobile phones in active mode using a tri-axis isotropic probe and electric field meter. Results: The highest electromagnetic field exposure was recorded when th...

  12. 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.

  13. Environmental radioactivity and radiation exposure in 2013; Umweltradioaktivitaet und Strahlenbelastung im Jahr 2013

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    The report on the environmental radioactivity and radiation exposure in 2013 covers the natural radiation exposure due to radon, food, cosmic and terrestric radiation and the radiation exposure due to nuclear medicine nuclear facilities, mining, industry household and fallout. Special issues are the occupational radiation exposure the medical radiation exposure and the exposure to non-ionizing radiation.

  14. Radiation exposure to operators during vertebroplasty.

    Science.gov (United States)

    Komemushi, Atsushi; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Sawada, Satoshi

    2005-10-01

    To measure the radiation received by physicians during percutaneous vertebroplasty with use of two types of injection devices with the interventional equipment guided by computed tomography (CT) and an angiographic/CT system. Twenty consecutive patients who underwent percutaneous vertebroplasty were included in this study. The patients were divided into two groups, the 1-mL syringe group and the bone cement injector group. Percutaneous vertebroplasties were performed with the IVR-CT system, which combines angiographic and CT equipment with a single fluoroscopy table. Radiation dose to operators was measured as equivalent dose penetrating at a 10-mm tissue depth with use of electronic personal dosimeters attached outside and inside lead aprons. Effective radiation dose (HE) was estimated based on the radiation dose outside the lead apron (Ha) and the radiation dose inside the lead apron (Hb). Differences between the groups in doses and fluoroscopic duration were analyzed. In the 1-mL syringe group and bone cement injector group, mean Ha measurements were 320.8 microSv and 116.2 microSv, respectively. Mean Hb measurements were 14.5 microSv versus 7.8 microSv and mean HE measurements were 48.2 microSv versus 19.7 microSv. Significant differences were found in Ha, Hb, and HE. However, duration of fluoroscopy did not differ significantly between groups. Radiation dose was relatively high for operators performing percutaneous vertebroplasty. The bone cement injector was useful in reducing the level of radiation exposure to operators during vertebroplasty.

  15. Dose to the Bladder Neck Is the Most Important Predictor for Acute and Late Toxicity After Low-Dose-Rate Prostate Brachytherapy: Implications for Establishing New Dose Constraints for Treatment Planning

    Energy Technology Data Exchange (ETDEWEB)

    Hathout, Lara; Folkert, Michael R.; Kollmeier, Marisa A.; Yamada, Yoshiya [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Cohen, Gil' ad N. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Zelefsky, Michael J., E-mail: zelefskm@mskcc.org [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States)

    2014-10-01

    Purpose: To identify an anatomic structure predictive for acute (AUT) and late (LUT) urinary toxicity in patients with prostate cancer treated with low-dose-rate brachytherapy (LDR) with or without external beam radiation therapy (EBRT). Methods and Materials: From July 2002 to January 2013, 927 patients with prostate cancer (median age, 66 years) underwent LDR brachytherapy with Iodine 125 (n=753) or Palladium 103 (n=174) as definitive treatment (n=478) and as a boost (n=449) followed by supplemental EBRT (median dose, 50.4 Gy). Structures contoured on the computed tomographic (CT) scan on day 0 after implantation included prostate, urethra, bladder, and the bladder neck, defined as 5 mm around the urethra between the catheter balloon and the prostatic urethra. AUT and LUT were assessed with the Common Terminology Criteria for Adverse Events, version4. Clinical and dosimetric factors associated with AUT and LUT were analyzed with Cox regression and receiver operating characteristic analysis to calculate area under the receiver operator curve (ROC) (AUC). Results: Grade ≥2 AUT and grade ≥2 LUT occurred in 520 patients (56%) and 154 patients (20%), respectively. No grade 4 toxicities were observed. Bladder neck D2cc retained a significant association with AUT (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.03-1.04; P<.0001) and LUT (HR, 1.01; 95% CI, 1.00-1.03; P=.014) on multivariable analysis. In a comparison of bladder neck with the standard dosimetric variables by use of ROC analysis (prostate V100 >90%, D90 >100%, V150 >60%, urethra D20 >130%), bladder neck D2cc >50% was shown to have the strongest prognostic power for AUT (AUC, 0.697; P<.0001) and LUT (AUC, 0.620; P<.001). Conclusions: Bladder neck D2cc >50% was the strongest predictor for grade ≥2 AUT and LUT in patients treated with LDR brachytherapy. These data support inclusion of bladder neck constraints into brachytherapy planning to decrease urinary toxicity.

  16. DOE 2012 Occupational Radiation Exposure October 2013

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-02-02

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. As an indicator of the overall amount of radiation dose received during the conduct of operations at DOE, the report includes information on collective total effective dose (TED). The TED is comprised of the effective dose (ED) from external sources, which includes neutron and photon radiation, and the internal committed effective dose (CED), which results from the intake of radioactive material into the body. The collective ED from photon exposure decreased by 23% between 2011 and 2012, while the neutron dose increased by 5%. The internal dose components of the collective TED decreased by 7%. Over the past 5-year period, 99.99% of the individuals receiving measurable TED have received doses below the 2 roentgen equivalent in man (rems) (20 millisievert [mSv]) TED administrative control level (ACL), which is well below the DOE regulatory limit of 5 rems (50 mSv) TED annually. The

  17. Health effects in women exposed to low levels of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1982-06-01

    There are three delayed health effects of radiation which appear at the present time to have importance to women in radiation protection. These are: (1) the probability of cancer-induction at low doses and low-dose rates; (2) the consideration of those cancers in women, notably the breast and the thyroid, attributable to radiation exposure; and (3) the probability of induction of developmental abnormalities in the newborn following low-dose exposure in utero. The bases for the concern over these effects are discussed. (ACR)

  18. Cosmic radiation exposure at aircraft crew workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Latocha, M.; Beck, P.; Rollet, S. [ARC Seibersdorf Research, Seibersdorf (Austria); Latocha, M. [Institute of Nuclear Physics Polish Academy of Sciences, Krakow (Poland)

    2006-07-01

    E.U.R.A.D.O.S. working group W.G.5. on air crew dosimetry coordinated research of some 24 international institutes to exchange experimental data and results of calculations of the radiation exposure in aircraft altitudes due to cosmic radiation. The purpose was to provide a data-set for all European Union Member States for the assessment of individual doses, the validity of different approaches, and to provide an input to technical recommendations by the Article 31 group of experts and the European Commission. The results of this work have been recently published and are available for the international community. The radiation protection quantity of interest is effective dose, E (ISO), but the comparison of measurement results and the results of calculations, is done in terms of the operational quantity ambient dose equivalent, H{sup *}(10). This paper gives an overview of the E.U.R.A.D.O.S. Aircraft Crew In-Flight Database which was implemented under the responsibility of A.R.C. Seibersdorf research. It discusses calculation models for air crew dose assessment comparing them with measurements contained in this database. Further it presents current developments using updated information of galactic cosmic radiation proton spectra and new results of the recently finalized European research project D.O.S.M.A.X. on dosimetry of aircraft crew at solar maximum. (authors)

  19. DOE 2008 Occupational Radiation Exposure October 2009

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy, Office of Health, Safety and Security

    2009-10-01

    A major priority of the U.S. Department of Energy (DOE) is to ensure the health, safety, and security of DOE employees, contractors, and subcontractors. The Office of Health, Safety and Security (HSS) provides the corporate-level leadership and strategic vision necessary to better coordinate and integrate health, safety, environment, security, enforcement, and independent oversight programs. One function that supports this mission is the DOE Corporate Operating Experience Program that provides collection, analysis, and dissemination of performance indicators, such as occupational radiation exposure information. This analysis supports corporate decision-making and synthesizes operational information to support continuous environment, safety, and health improvement across the DOE complex.

  20. Dose Response for Chromosome Aberrations in Human Lymphocytes and Fibroblasts After Exposure to Very Low Dose of High Let Radiation

    Science.gov (United States)

    Hada, M.; George, K.; Chappell, L.; Cucinotta, F. A.

    2011-01-01

    The relationship between biological effects and low doses of absorbed radiation is still uncertain, especially for high LET radiation exposure. Estimates of risks from low-dose and low-dose-rates are often extrapolated using data from Japanese atomic bomb survivor with either linear or linear quadratic models of fit. In this study, chromosome aberrations were measured in human peripheral blood lymphocytes and normal skin fibroblasts cells after exposure to very low dose (0.01 - 0.20 Gy) of 170 MeV/u Si-28 ions or 600 MeV/u Fe-56 ions, including doses where on average less than one direct ion traversal per cell nucleus occurs. Chromosomes were analyzed using the whole-chromosome fluorescence in situ hybridization (FISH) technique during the first cell division after irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). The responses for doses above 0.1 Gy (more than one ion traverses a cell) showed linear dose responses. However, for doses less than 0.1 Gy, both Si-28 ions and Fe-56 ions showed a dose independent response above background chromosome aberrations frequencies. Possible explanations for our results are non-targeted effects due to aberrant cell signaling [1], or delta-ray dose fluctuations [2] where a fraction of cells receive significant delta-ray doses due to the contributions of multiple ion tracks that do not directly traverse cell nuclei where chromosome aberrations are scored.

  1. Predictors of radiation exposure to providers during percutaneous nephrolithotomy

    Directory of Open Access Journals (Sweden)

    David L Wenzler

    2017-01-01

    Conclusion: Increased stone burden, partial or staghorn calculi, surgery and fluoroscopy duration, and absence of preexisting access were associated with high provider radiation exposure. Radiation safety awareness is essential to minimize exposure and to protect the patient and all providers from potential radiation injury.

  2. Radiation exposure from depleted uranium: The radiation bystander effect.

    Science.gov (United States)

    Miller, Alexandra C; Rivas, Rafael; Tesoro, Leonard; Kovalenko, Gregor; Kovaric, Nikola; Pavlovic, Peter; Brenner, David

    2017-09-15

    Depleted uranium (DU) is a radioactive heavy metal used primarily in military applications. Published data from our laboratory have demonstrated that DU exposure in vitro to immortalized human osteoblast cells (HOS) is both neoplastically transforming and genotoxic. In vivo studies have also demonstrated that DU is leukemogenic and genotoxic. DU possesses both a radiological (alpha particle) and chemical (metal) component but is generally considered a chemical biohazard. Studies have shown that alpha particle radiation does play a role in DU's toxic effects. Evidence has accumulated that non-irradiated cells in the vicinity of irradiated cells can have a response to ionization events. The purpose of this study was to determine if these "bystander effects" play a role in DU's toxic and neoplastic effects using HOS cells. We investigated the bystander responses between DU-exposed cells and non-exposed cells by co-culturing the two equal populations. Decreased cell survival and increased neoplastic transformation were observed in the non-DU exposed cells following 4 or 24h co-culture. In contrast Ni (II)- or Cr(VI)- exposed cells were unable to alter those biological effects in non-Ni(II) or non-Cr(VI) exposed co-cultured cells. Transfer experiments using medium from the DU-exposed and non-exposed co-cultured cells was able to cause adverse biological responses in cells; these results demonstrated that a factor (s) is secreted into the co-culture medium which is involved in this DU-associated bystander effect. This novel effect of DU exposure could have implications for radiation risk and for health risk assessment associated with DU exposure. Copyright © 2017. Published by Elsevier Inc.

  3. Solid cancer mortality associated with chronic external radiation exposure at the French atomic energy commission and nuclear fuel company.

    Science.gov (United States)

    Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

    2011-07-01

    Studies of nuclear workers make it possible to directly quantify the risks associated with ionizing radiation exposure at low doses and low dose rates. Studies of the CEA (Commissariat à l'Energie Atomique) and AREVA Nuclear Cycle (AREVA NC) cohort, currently the most informative such group in France, describe the long-term risk to nuclear workers associated with external exposure. Our aim is to assess the risk of mortality from solid cancers among CEA and AREVA NC nuclear workers and its association with external radiation exposure. Standardized mortality ratios (SMRs) were calculated and internal Poisson regressions were conducted, controlling for the main confounding factors [sex, attained age, calendar period, company and socioeconomic status (SES)]. During the period 1968-2004, there were 2,035 solid cancers among the 36,769 CEA-AREVA NC workers. Cumulative external radiation exposure was assessed for the period 1950-2004, and the mean cumulative dose was 12.1 mSv. Mortality rates for all causes and all solid cancers were both significantly lower in this cohort than in the general population. A significant excess of deaths from pleural cancer, not associated with cumulative external dose, was observed, probably due to past asbestos exposure. We observed a significant excess of melanoma, also unassociated with dose. Although cumulative external dose was not associated with mortality from all solid cancers, the central estimated excess relative risk (ERR) per Sv of 0.46 for solid cancer mortality was higher than the 0.26 calculated for male Hiroshima and Nagasaki A-bomb survivors 50 years or older and exposed at the age of 30 years or older. The modification of our results after stratification for SES demonstrates the importance of this characteristic in occupational studies, because it makes it possible to take class-based lifestyle differences into account, at least partly. These results show the great potential of a further joint international study of

  4. Non-Target Effect for Chromosome Aberrations in Human Lymphocytes and Fibroblasts After Exposure to Very Low Doses of High LET Radiation

    Science.gov (United States)

    Hada, Megumi; George, Kerry A.; Cucinotta, F. A.

    2011-01-01

    The relationship between biological effects and low doses of absorbed radiation is still uncertain, especially for high LET radiation exposure. Estimates of risks from low-dose and low-dose-rates are often extrapolated using data from Japanese atomic bomb survivor with either linear or linear quadratic models of fit. In this study, chromosome aberrations were measured in human peripheral blood lymphocytes and normal skin fibroblasts cells after exposure to very low dose (.01 - 0.2 Gy) of 170 MeV/u Si-28-ions or 600 MeV/u Fe-56-ions. Chromosomes were analyzed using the whole chromosome fluorescence in situ hybridization (FISH) technique during the first cell division after irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). The curves for doses above 0.1 Gy were more than one ion traverses a cell showed linear dose responses. However, for doses less than 0.1 Gy, Si-28-ions showed no dose response, suggesting a non-targeted effect when less than one ion traversal occurs. Additional findings for Fe-56 will be discussed.

  5. Ocular ultraviolet radiation exposure of welders.

    Science.gov (United States)

    Tenkate, Thomas D

    2017-03-15

    I read with interest a recent paper in your journal by Slagor et al on the risk of cataract in relation to metal arc welding (1). The authors highlight that even though welders are exposed to substantial levels of ultraviolet radiation (UVR), "no studies have reported data on how much UVR welders' eyes are exposed to during a working day. Thus, we do not know whether welders are more or less exposed to UVR than outdoor workers" (1, p451). Undertaking accurate exposure assessment of UVR from welding arcs is difficult, however, two studies have reported ocular/facial UVR levels underneath welding helmets (2, 3). In the first paper, UVR levels were measured using polysulphone film dosimeters applied to the cheeks of a patient who suffered from severe facial dermatitis (2). UVR levels of four times the American Conference of Governmental Industrial Hygienists (ACGIH) maximum permissible exposure (MPE) (4) were measured on the workers left cheek and nine times the MPE on the right cheek. The authors concluded that the workers dermatitis was likely to have been due to the UVR exposure received during welding. In the other paper, a comprehensive exposure assessment of personal UVR exposure of workers in a welding environment was reported (3). The study was conducted at a metal fabrication workshop with participants being welders, boilermakers and non-welders (eg, supervisors, fitters, machinists). Polysulphone film dosimeters were again used to measure UVR exposure of the workers, with badges worn on the clothing of workers (in the chest area), on the exterior of welding helmets, attached to 11 locations on the inside of welding helmets, and on the bridge and side-shields of safety spectacles. Dosimeters were also attached to surfaces throughout the workshop to measure ambient UVR levels. For welding subjects, mean 8-hour UVR doses within the welding helmets ranged from around 9 mJ/cm (2)(3×MPE) on the inside of the helmets to around 15 mJ/cm (2)(5×MPE) on the headband

  6. Cell/Tissue Culture Radiation Exposure Facility Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a Cell/Tissue Culture Radiation Exposure Facility (CTC-REF) to enable radiobiologists to investigate the real-time radiation effects on...

  7. Occupational radiation exposures in research laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Vaccari, S.; Papotti, E. [Parma Univ., Health Physics (Italy); Pedrazzi, G. [Parma Univ., Dept. of Public Health (Italy)

    2006-07-01

    Radioactive sources are widely used in many research activities at University centers. In particular, the activities concerning use of sealed form ({sup 57}Co in Moessbauer application) and unsealed form ({sup 3}H, {sup 14}C, {sup 32}P in radioisotope laboratories) are analyzed. The radiological impact of these materials and potential effective doses to researchers and members of the public were evaluated to show compliance with regulatory limits. A review of the procedures performed by researchers and technicians in the research laboratories with the relative dose evaluations is presented in different situations, including normal operations and emergency situations, for example the fire. A study of the possible exposure to radiation by workers, restricted groups of people, and public in general, as well as environmental releases, is presented. (authors)

  8. Measurement of absorbed dose and proposed radiation exposure level

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Takayuki; Koizumi, Masayuki; Furukawa, Tomo [Tokai Univ., Isehara, Kanagawa (Japan). Hospital

    2003-03-01

    Absorbed dose was measured in clinical X-ray examinations using thermoluminescence dosimeter (TLD). Moreover, we distributed the levels of radiation exposure into 3 classes. The presumed dose of the internal organs, e.g., uterus dose, was computed to depth doses with a surface dose. This information provides a prediction of the influence of radiation, and the examination can be performed with the informed consent of the patient. Moreover, we examined the distribution of the level of absorbed dose. We proposed two kinds of radiation exposure level, one to the fetus in a pregnant woman and a general level of radiation exposure that is not applied to pregnant women. The levels were as follows: 0.5 mGy and 100 mGy were considered the boundaries for fetal radiation exposure in a pregnant woman, and 200 mGy and 3 Gy were considered the boundaries for the general level of radiation exposure (excluding pregnant women). (author)

  9. Effects of high vs low-level radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Bond, V.P.

    1983-01-01

    In order to appreciate adequately the various possible effects of radiation, particularly from high-level vs low-level radiation exposure (HLRE, vs LLRE), it is necessary to understand the substantial differences between (a) exposure as used in exposure-incidence curves, which are always initially linear and without threshold, and (b) dose as used in dose-response curves, which always have a threshold, above which the function is curvilinear with increasing slope. The differences are discussed first in terms of generally familiar nonradiation situations involving dose vs exposure, and then specifically in terms of exposure to radiation, vs a dose of radiation. Examples are given of relevant biomedical findings illustrating that, while dose can be used with HLRE, it is inappropriate and misleading the LLRE where exposure is the conceptually correct measure of the amount of radiation involved.

  10. Predictors of radiation exposure to providers during percutaneous nephrolithotomy

    Science.gov (United States)

    Wenzler, David L.; Abbott, Joel E.; Su, Jeannie J.; Shi, William; Slater, Richard; Miller, Daniel; Siemens, Michelle J.; Sur, Roger L.

    2017-01-01

    Background: Limited studies have reported on radiation risks of increased ionizing radiation exposure to medical personnel in the urologic community. Fluoroscopy is readily used in many urologic surgical procedures. The aim of this study was to determine radiation exposure to all operating room personnel during percutaneous nephrolithotomy (PNL), commonly performed for large renal or complex stones. Materials and Methods: We prospectively collected personnel exposure data for all PNL cases at two academic institutions. This was collected using the Instadose™ dosimeter and reported both continuously and categorically as high and low dose using a 10 mrem dose threshold, the approximate amount of radiation received from one single chest X-ray. Predictors of increased radiation exposure were determined using multivariate analysis. Results: A total of 91 PNL cases in 66 patients were reviewed. Median surgery duration and fluoroscopy time were 142 (38–368) min and 263 (19–1809) sec, respectively. Median attending urologist, urology resident, anesthesia, and nurse radiation exposure per case was 4 (0–111), 4 (0–21), 0 (0–5), and 0 (0–5) mrem, respectively. On univariate analysis, stone area, partial or staghorn calculi, surgery duration, and fluoroscopy time were associated with high attending urologist and resident radiation exposure. Preexisting access that was utilized was negatively associated with resident radiation exposure. However, on multivariate analysis, only fluoroscopy duration remained significant for attending urologist radiation exposure. Conclusion: Increased stone burden, partial or staghorn calculi, surgery and fluoroscopy duration, and absence of preexisting access were associated with high provider radiation exposure. Radiation safety awareness is essential to minimize exposure and to protect the patient and all providers from potential radiation injury. PMID:28216931

  11. Early effects comparison of X-rays delivered at high-dose-rate pulses by a plasma focus device and at low dose rate on human tumour cells.

    Science.gov (United States)

    Virelli, A; Zironi, I; Pasi, F; Ceccolini, E; Nano, R; Facoetti, A; Gavoçi, E; Fiore, M R; Rocchi, F; Mostacci, D; Cucchi, G; Castellani, G; Sumini, M; Orecchia, R

    2015-09-01

    A comparative study has been performed on the effects of high-dose-rate (DR) X-ray beams produced by a plasma focus device (PFMA-3), to exploit its potential medical applications (e.g. radiotherapy), and low-DR X-ray beams produced by a conventional source (XRT). Experiments have been performed at 0.5 and 2 Gy doses on a human glioblastoma cell line (T98G). Cell proliferation rate and potassium outward currents (IK) have been investigated by time lapse imaging and patch clamp recordings. The results showed that PFMA-3 irradiation has a greater capability to reduce the proliferation rate activity with respect to XRT, while it does not affect IK of T98G cells at any of the dose levels tested. XRT irradiation significantly reduces the mean IK amplitude of T98G cells only at 0.5 Gy. This work confirms that the DR, and therefore the source of radiation, is crucial for the planning and optimisation of radiotherapy applications.

  12. Integrative Radiation Biology

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos-Hoff, Mary Helen [New York University School of Medicine, NY (United States)

    2015-02-27

    We plan to study tissue-level mechanisms important to human breast radiation carcinogenesis. We propose that the cell biology of irradiated tissues reveals a coordinated multicellular damage response program in which individual cell contributions are primarily directed towards suppression of carcinogenesis and reestablishment of homeostasis. We identified transforming growth factor β1 (TGFβ) as a pivotal signal. Notably, we have discovered that TGFβ suppresses genomic instability by controlling the intrinsic DNA damage response and centrosome integrity. However, TGFβ also mediates disruption of microenvironment interactions, which drive epithelial to mesenchymal transition in irradiated human mammary epithelial cells. This apparent paradox of positive and negative controls by TGFβ is the topic of the present proposal. First, we postulate that these phenotypes manifest differentially following fractionated or chronic exposures; second, that the interactions of multiple cell types in tissues modify the responses evident in this single cell type culture models. The goals are to: 1) study the effect of low dose rate and fractionated radiation exposure in combination with TGFβ on the irradiated phenotype and genomic instability of non-malignant human epithelial cells; and 2) determine whether stromal-epithelial interactions suppress the irradiated phenotype in cell culture and the humanized mammary mouse model. These data will be used to 3) develop a systems biology model that integrates radiation effects across multiple levels of tissue organization and time. Modeling multicellular radiation responses coordinated via extracellular signaling could have a significant impact on the extrapolation of human health risks from high dose to low dose/rate radiation exposure.

  13. Patterns of Recurrence After Low-Dose-Rate Prostate Brachytherapy: A Population-Based Study of 2223 Consecutive Low- and Intermediate-Risk Patients

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Andrea C.; Morris, W. James, E-mail: JMorris@bccancer.bc.ca; Pickles, Tom; Keyes, Mira; McKenzie, Michael; Tyldesley, Scott

    2015-03-15

    Objectives: This study examined patterns of recurrence after low–dose-rate prostate brachytherapy (LDR-PB), estimated local recurrence rate and compared that rate to the estimated local recurrence rate after radical prostatectomy (RP). Methods and Materials: A prospective database was maintained with clinical, dosimetric, and outcome data for all LDR-PB implantation procedures performed at our institution. From 1998 to 2008, 2223 patients with prostate cancer received LDR-PB without supplemental external beam radiation therapy. Patients who developed Phoenix-defined biochemical failure were reviewed for sites of relapse and investigations completed. Results: At a median follow-up of 5 years, 108 of 2223 patients (4.8%) developed biochemical relapse. In 1 additional patient, local relapse was found on transurethral prostate resection, but his prostate-specific antigen concentration was well short of triggering Phoenix-defined failure. Of the 109 patients with disease relapse, 18 of 2223 (0.8%) had a proven local recurrence, and 30 of 2223 (1.3%) had a proven distant recurrence. The remaining 61 of 2223 patients (2.7%) had unidentified sites of recurrence; of these, 57 patients (93%) had digital rectal examinations (DREs), 18 (30%) had post-treatment biopsies, 45 (74%) had bone scans, and 34 (56%) had computed tomography imaging of the abdomen and pelvis. If every biochemical failure were local, the local recurrence rate would be as high as 4.9%; however, by excluding those with proven distant failure and those with both a negative DRE and biopsy, we estimate that the local recurrence rate is 2.7% or less. Conclusions: In the context of limitations of the study design, our population-based analysis indicates that the local recurrence rate after LDR-PB is as low or lower than that after RP in our jurisdiction.

  14. Conditioned instrumental behaviour in the rat: Effects of prenatal irradiation with various low dose-rate doses. Instrumentelle Verhaltensuntersuchungen an der Ratte: Ueber die Wirkung verschiedener Dosen einer praenatalen Bestrahlung niedriger Dosisleistung

    Energy Technology Data Exchange (ETDEWEB)

    Klug, H.

    1986-01-01

    4 groups of rats of the Wistar-strain were subjected to ..gamma..-irradiation on the 16th day of gestation. 5 rats received 0,6 Gy low dose rate irradiation, 5 animals received 0,9 Gy low dose and 6 high dose irradiation, 3 females were shamirradiated. The male offspring of these 3 irradiation groups and 1 control group were tested for locomotor coordination on parallel bars and in a water maze. The female offspring were used in an operant conditioning test. The locomotor test showed slight impairment of locomotor coordination in those animals irradiated with 0,9 Gy high dose rate. Swimming ability was significantly impaired by irradiation with 0,9 Gy high dose rate. Performance in the operant conditioning task was improved by irradiation with 0,9 Gy both low and high dose rate. The 0,9 Gy high dose rate group learned faster than all the other groups. For the dose of 0,9 Gy a significant dose rate effect could be observed. For the dose of 0,6 Gy a similar tendency was observed, differences between 0,6 Gy high and low dose rate and controls not being significant.

  15. Maintenance hemodialysis patients have high cumulative radiation exposure.

    LENUS (Irish Health Repository)

    Kinsella, Sinead M

    2010-10-01

    Hemodialysis is associated with an increased risk of neoplasms which may result, at least in part, from exposure to ionizing radiation associated with frequent radiographic procedures. In order to estimate the average radiation exposure of those on hemodialysis, we conducted a retrospective study of 100 patients in a university-based dialysis unit followed for a median of 3.4 years. The number and type of radiological procedures were obtained from a central radiology database, and the cumulative effective radiation dose was calculated using standardized, procedure-specific radiation levels. The median annual radiation dose was 6.9 millisieverts (mSv) per patient-year. However, 14 patients had an annual cumulative effective radiation dose over 20 mSv, the upper averaged annual limit for occupational exposure. The median total cumulative effective radiation dose per patient over the study period was 21.7 mSv, in which 13 patients had a total cumulative effective radiation dose over 75 mSv, a value reported to be associated with a 7% increased risk of cancer-related mortality. Two-thirds of the total cumulative effective radiation dose was due to CT scanning. The average radiation exposure was significantly associated with the cause of end-stage renal disease, history of ischemic heart disease, transplant waitlist status, number of in-patient hospital days over follow-up, and death during the study period. These results highlight the substantial exposure to ionizing radiation in hemodialysis patients.

  16. Impact of climate change on occupational exposure to solar radiation.

    Science.gov (United States)

    Grandi, Carlo; Borra, Massimo; Militello, Andrea; Polichetti, Alessandro

    2016-01-01

    Occupational exposure to solar radiation may induce both acute and long-term effects on skin and eyes. Personal exposure is very difficult to assess accurately, as it depends on environmental, organisational and individual factors. The ongoing climate change interacting with stratospheric ozone dynamics may affect occupational exposure to solar radiation. In addition, tropospheric levels of environmental pollutants interacting with solar radiation may be altered by climate dynamics, so introducing another variable affecting the overall exposure to solar radiation. Given the uncertainties regarding the direction of changes in exposure to solar radiation due to climate change, compliance of outdoor workers with protective measures and a proper health surveillance are crucial. At the same time, education and training, along with the promotion of healthier lifestyles, are of paramount importance.

  17. DOE occupational radiation exposure. Report 1992--1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The DOE Occupational Radiation Exposure Report, 1992-1994 reports occupational radiation exposures incurred by individuals at US Department of Energy (DOE) facilities from 1992 through 1994. This report includes occupational radiation exposure information for all DOE employees, contractors, subcontractors, and visitors. This information is analyzed and trended over time to provide a measure of the DOE`s performance in protecting its workers from radiation. Occupational radiation exposure at DOE has been decreasing over the past 5 years. In particular, doses in the higher dose ranges are decreasing, including the number of doses in excess of the DOE limits and doses in excess of the 2 rem Administrative Control Level (ACL). This is an indication of greater attention being given to protecting these individuals from radiation in the workplace.

  18. DOE occupational radiation exposure. Report 1992--1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    The DOE Occupational Radiation Exposure Report, 1992-1994 reports occupational radiation exposures incurred by individuals at US Department of Energy (DOE) facilities from 1992 through 1994. This report includes occupational radiation exposure information for all DOE employees, contractors, subcontractors, and visitors. This information is analyzed and trended over time to provide a measure of the DOE`s performance in protecting its workers from radiation. Occupational radiation exposure at DOE has been decreasing over the past 5 years. In particular, doses in the higher dose ranges are decreasing, including the number of doses in excess of the DOE limits and doses in excess of the 2 rem Administrative Control Level (ACL). This is an indication of greater attention being given to protecting these individuals from radiation in the workplace.

  19. Optimizing radiation exposure for CT localizer radiographs

    Energy Technology Data Exchange (ETDEWEB)

    Bohrer, Evelyn; Maeder, Ulf; Fiebich, Martin [Univ. of Applied Sciences, Giessen (Germany). Inst. of Medical Physics and Radiation Protection-IMPS; Schaefer, Stefan; Krombach, Gabriele A. [Univ. Hospital Giessen (Germany). Dept. of Radiology; Noel, Peter B. [Technische Univ. Muenchen (Germany). Dept. of Diagnostic and Interventional Radiology

    2017-08-01

    The trend towards submillisievert CT scans leads to a higher dose fraction of localizer radiographs in CT examinations. The already existing technical capabilities make dose optimization of localizer radiographs worthwhile. Modern CT scanners apply automatic exposure control (AEC) based on attenuation data in such a localizer. Therefore not only this aspect but also the detectability of anatomical landmarks in the localizer for the desired CT scan range adjustment needs to be considered. The effective dose of a head, chest, and abdomen-pelvis localizer radiograph with standard factory settings and user-optimized settings was determined using Monte Carlo simulations. CT examinations of an anthropomorphic phantom were performed using multiple sets of acquisition parameters for the localizer radiograph and the AEC for the subsequent helical CT scan. Anatomical landmarks were defined to assess the image quality of the localizer. CTDI{sub vol} and effective mAs per slice of the helical CT scan were recorded to examine the impact of localizer settings on a helical CT scan. The dose of the localizer radiograph could be decreased by more than 90% while the image quality remained sufficient when selecting the lowest available settings (80 kVp, 20 mA, pa tube position). The tube position during localizer acquisition had a greater impact on the AEC than the reduction of tube voltage and tube current. Except for the use of a pa tube position, all changes of acquisition parameters for the localizer resulted in a decreased total radiation exposure. A dose reduction of CT localizer radiograph is necessary and possible. In the examined CT system there was no negative impact on the modulated helical CT scan when the lowest tube voltage and tube current were used for the localizer.

  20. Radiation exposure in gastroenterology: improving patient and staff protection.

    LENUS (Irish Health Repository)

    Ho, Immanuel K H

    2014-08-01

    Medical imaging involving the use of ionizing radiation has brought enormous benefits to society and patients. In the past several decades, exposure to medical radiation has increased markedly, driven primarily by the use of computed tomography. Ionizing radiation has been linked to carcinogenesis. Whether low-dose medical radiation exposure will result in the development of malignancy is uncertain. This paper reviews the current evidence for such risk, and aims to inform the gastroenterologist of dosages of radiation associated with commonly ordered procedures and diagnostic tests in clinical practice. The use of medical radiation must always be justified and must enable patients to be exposed at the lowest reasonable dose. Recommendations provided herein for minimizing radiation exposure are based on currently available evidence and Working Party expert consensus.

  1. DOE Basic Overview of Occupational Radiation Exposure_2011 pamphlet

    Energy Technology Data Exchange (ETDEWEB)

    ORAU

    2012-08-08

    This pamphlet focusses on two HSS activities that help ensure radiation exposures are accurately assessed and recorded, namely: 1) the quality and accuracy of occupational radiation exposure monitoring, and 2) the recording, reporting, analysis, and dissemination of the monitoring results. It is intended to provide a short summary of two specific HSS programs that aid in the oversight of radiation protection activities at DOE. The Department of Energy Laboratory Accreditation Program (DOELAP) is in place to ensure that radiation exposure monitoring at all DOE sites is precise and accurate, and conforms to national and international performance and quality assurance standards. The DOE Radiation Exposure Monitoring Systems (REMS) program provides for the collection, analysis, and dissemination of occupational radiation exposure information. The annual REMS report is a valuable tool for managing radiological safety programs and for developing policies to protect individuals from occupational exposure to radiation. In tandem, these programs provide DOE management and workers an assurance that occupational radiation exposures are accurately measured, analyzed, and reported.

  2. Low and high dose rate heavy ion radiation-induced intestinal and colonic tumorigenesis in APC1638N/+ mice

    Science.gov (United States)

    Suman, Shubhankar; Kumar, Santosh; Moon, Bo-Hyun; Fornace, Albert J.; Datta, Kamal

    2017-05-01

    Ionizing radiation (IR) is a recognized risk factor for colorectal cancer (CRC) and astronauts undertaking long duration space missions are expected to receive IR doses in excess of permissible limits with implications for colorectal carcinogenesis. Exposure to IR in outer space occurs at low doses and dose rates, and energetic heavy ions due to their high linear energy transfer (high-LET) characteristics remain a major concern for CRC risk in astronauts. Previously, we have demonstrated that intestinal tumorigenesis in a mouse model (APC1638N/+) of human colorectal cancer was significantly higher after exposure to high dose rate energetic heavy ions relative to low-LET γ radiation. The purpose of the current study was to compare intestinal tumorigenesis in APC1638N/+ mice after exposure to energetic heavy ions at high (50 cGy/min) and relatively low (0.33 cGy/min) dose rate. Male and female mice (6-8 weeks old) were exposed to either 10 or 50 cGy of 28Si (energy: 300 MeV/n; LET: 70 keV/μm) or 56Fe (energy: 1000 MeV/n; LET: 148 keV/μm) ions at NASA Space Radiation Laboratory in Brookhaven National Laboratory. Mice (n = 20 mice/group) were euthanized and intestinal and colon tumor frequency and size were counted 150 days after radiation exposure. Intestinal tumorigenesis in male mice exposed to 56Fe was similar for high and low dose rate exposures. Although male mice showed a decreasing trend at low dose rate relative to high dose rate exposures, the differences in tumor frequency between the two types of exposures were not statistically significant after 28Si radiation. In female mice, intestinal tumor frequency was similar for both radiation type and dose rates tested. In both male and female mice intestinal tumor size was not different after high and low dose rate radiation exposures. Colon tumor frequency in male and female mice after high and low dose rate energetic heavy ions was also not significantly different. In conclusion, intestinal and colonic tumor

  3. Low and high dose rate heavy ion radiation-induced intestinal and colonic tumorigenesis in APC(1638N/+) mice.

    Science.gov (United States)

    Suman, Shubhankar; Kumar, Santosh; Moon, Bo-Hyun; Fornace, Albert J; Datta, Kamal

    2017-05-01

    Ionizing radiation (IR) is a recognized risk factor for colorectal cancer (CRC) and astronauts undertaking long duration space missions are expected to receive IR doses in excess of permissible limits with implications for colorectal carcinogenesis. Exposure to IR in outer space occurs at low doses and dose rates, and energetic heavy ions due to their high linear energy transfer (high-LET) characteristics remain a major concern for CRC risk in astronauts. Previously, we have demonstrated that intestinal tumorigenesis in a mouse model (APC(1638N/+)) of human colorectal cancer was significantly higher after exposure to high dose rate energetic heavy ions relative to low-LET γ radiation. The purpose of the current study was to compare intestinal tumorigenesis in APC(1638N/+) mice after exposure to energetic heavy ions at high (50cGy/min) and relatively low (0.33cGy/min) dose rate. Male and female mice (6-8 weeks old) were exposed to either 10 or 50cGy of (28)Si (energy: 300MeV/n; LET: 70keV/μm) or (56)Fe (energy: 1000MeV/n; LET: 148keV/μm) ions at NASA Space Radiation Laboratory in Brookhaven National Laboratory. Mice (n=20 mice/group) were euthanized and intestinal and colon tumor frequency and size were counted 150days after radiation exposure. Intestinal tumorigenesis in male mice exposed to (56)Fe was similar for high and low dose rate exposures. Although male mice showed a decreasing trend at low dose rate relative to high dose rate exposures, the differences in tumor frequency between the two types of exposures were not statistically significant after (28)Si radiation. In female mice, intestinal tumor frequency was similar for both radiation type and dose rates tested. In both male and female mice intestinal tumor size was not different after high and low dose rate radiation exposures. Colon tumor frequency in male and female mice after high and low dose rate energetic heavy ions was also not significantly different. In conclusion, intestinal and colonic

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

    OpenAIRE

    Jolyon H Hendry; Simon, Steven L.; Wojcik, Andrzej; Sohrabi, Mehdi; Burkart, Werner; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    2009-01-01

    Natural radiation is the major source of human exposure to ionising radiation, and its largest contributing component to effective dose arises from inhalation of 222Rn 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 li...

  5. DOE 2010 Occupational Radiation Exposure November 2011

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Department of Energy, Office of Health, Safety and Security, Office of Analysis

    2011-11-11

    This report discusses radiation protection and dose reporting requirements, presents the 2010 occupational radiation dose data trended over the past 5 years, and includes instructions to submit successful ALARA projects.

  6. Variation of space radiation exposure inside spherical and hemispherical geometries

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Z.W. [Department of Physics, East Carolina University, C-209 Howell Science Complex, Greenville, NC 27858-4353 (United States); National Space Science and Technology Center, University of Alabama in Huntsville, Huntsville, AL 35805 (United States)], E-mail: linz@ecu.edu; Baalla, Y. [University of Tennessee Space Institute, Tullahoma, TN 37388 (United States); Townsend, L.W. [Department of Nuclear Engineering, University of Tennessee at Knoxville, Knoxville, TN 37996 (United States)

    2009-04-15

    We calculate the space radiation exposure to blood-forming organs everywhere inside a hemispherical dome that represents a lunar habitat. We derive the analytical pathlength distribution from any point inside a hemispherical or a spherical shell. Because the average pathlength increases with the distance from the center, the center of the hemispherical dome on the lunar surface has the largest radiation exposure while locations on the inner surface of the dome have the lowest exposure. This conclusion differs from an earlier study on a hemispherical dome but agrees with another earlier study on a spherical-shell shield. We also find that the reduction in the radiation exposure from the center to the inner edge of the dome can be as large as a factor of 3 or more for the radiation from solar particle events while being smaller for the radiation from galactic cosmic rays.

  7. The Relationship between Ultraviolet Radiation Exposure and Vitamin D Status

    Directory of Open Access Journals (Sweden)

    Ola Engelsen

    2010-05-01

    Full Text Available This paper reviews the main factors influencing the synthesis of vitamin D, with particular focus on ultraviolet radiation exposure. On the global level, the main source of vitamin D is the sun. The effect of solar radiation on vitamin D synthesis depends to some extent on the initial vitamin D levels. At moderate to high latitudes, diet becomes an increasingly important source of vitamin D due to decreased solar intensity and cold temperatures, which discourage skin exposure. During the mid-winter season, these factors result in decreased solar radiation exposure, hindering extensively the synthesis of vitamin D in these populations.

  8. Gene Expression Profiling of Biological Pathway Alterations by Radiation Exposure

    Directory of Open Access Journals (Sweden)

    Kuei-Fang Lee

    2014-01-01

    Full Text Available Though damage caused by radiation has been the focus of rigorous research, the mechanisms through which radiation exerts harmful effects on cells are complex and not well-understood. In particular, the influence of low dose radiation exposure on the regulation of genes and pathways remains unclear. In an attempt to investigate the molecular alterations induced by varying doses of radiation, a genome-wide expression analysis was conducted. Peripheral blood mononuclear cells were collected from five participants and each sample was subjected to 0.5 Gy, 1 Gy, 2.5 Gy, and 5 Gy of cobalt 60 radiation, followed by array-based expression profiling. Gene set enrichment analysis indicated that the immune system and cancer development pathways appeared to be the major affected targets by radiation exposure. Therefore, 1 Gy radioactive exposure seemed to be a critical threshold dosage. In fact, after 1 Gy radiation exposure, expression levels of several genes including FADD, TNFRSF10B, TNFRSF8, TNFRSF10A, TNFSF10, TNFSF8, CASP1, and CASP4 that are associated with carcinogenesis and metabolic disorders showed significant alterations. Our results suggest that exposure to low-dose radiation may elicit changes in metabolic and immune pathways, potentially increasing the risk of immune dysfunctions and metabolic disorders.

  9. electromagnetic radiation exposure from cellular base station

    African Journals Online (AJOL)

    eobe

    2DEPARTMENT OF ELECTRICAL/ELECTRONIC ENGINEERING, FEDERAL UNIVERSITY OF TECHNOLOGY, MINNA, ... electronic apparatus radiate electromagnetic energy ..... [11] Randerson, James, “Research fails to detect short-.

  10. Towards a novel modular architecture for CERN radiation monitoring

    CERN Document Server

    Boukabache, Hamza; Ducos, Gael; Cardines, Nicola; Bellotta, Antonio; Toner, Ciarán; Perrin, Daniel; Forkel-Wirth, Doris

    2017-01-01

    The European Organization for Nuclear Research (CERN) has the legal obligation to protect the public and the people working on its premises from any unjustified exposure to ionising radiation. In this context, radiation monitoring is one of the main concerns of the Radiation Protection Group. After 30 y of reliable service, the ARea CONtroller (ARCON) system is approaching the end of its lifecycle, which raises the need for new, more efficient radiation monitors with a high level of modularity to ensure better maintainability. Based on these two main principles, new detectors are currently being developed that will be capable of measuring very low dose rates down to 50 nSv h−1, whilst being able to measure radiation over an extensive range of 8 decades without any auto scaling. To reach these performances, CERN Radiation MOnitoring Electronics (CROME), the new generation of CERN radiation monitors, is based on the versatile architecture that includes new read-out electronics developed by the Instrumentation...

  11. Exposure of the Spanish population to radiation from natural sources

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Talavera, M.; Suarez, E.; Matarranz, J.L.; Salas, R.; Ramos, L. [Consejo de Seguridad Nuclear. Justo Dorado, Madrid (Spain)

    2006-07-01

    We have assessed the exposure of the Spanish population to natural radiation sources. The annual average effective dose is estimated to be 2.38 mSv, taking into account contributions from cosmic radiation (13.8%), terrestrial gamma radiation (39%), radon and thoron inhalation (34%) and ingestion (13.2%). Cosmic radiation doses were calculated from town altitude data. Terrestrial gamma ray exposure outdoors was derived from the M.A.R.N.A. (natural gamma radiation map of Spain). Indoor gamma ray exposure was calculated by multiplying the corresponding outdoor value conversion factor, which was obtained by a linear least-squares fit of experimental measurements. Radon doses were estimated from national surveys carried out throughout the country. To assess doses by ingestion of water and foodstuffs we considered the results from a detailed study on consumption habits by age and geographical area in Spain, promoted by C.S.N., and average radioactivity values from UNSCEAR. (authors)

  12. Intraoperative Radiation Exposure During Revision Total Ankle Replacement.

    Science.gov (United States)

    Roukis, Thomas S; Iceman, Kelli; Elliott, Andrew D

    2016-01-01

    Intraoperative C-arm image intensification is required for primary total ankle replacement implantation. Significant radiation exposure has been linked to these procedures; however, the radiation exposure during revision total ankle replacement remains unknown. Therefore, we sought to evaluate the radiation exposure encountered during revision total ankle replacement. The data from 41 patients were retrospectively analyzed from a prospective database: 19 Agility(™) to Agility(™); 4 Agility(™) to Custom Agility(™); 9 Agility(™) to INBONE(®) II; 5 Agility(™) to Salto Talaris(®) XT; 2 Scandinavian Total Ankle Replacement Prosthesis to Salto Talaris(®) XT; and 2 INBONE(®) I to INBONE(®) II revision total ankle replacements were performed. Two broad categories were identified: partial revision (Agility(™) to Agility(™), Agility(™) to Custom Agility(™), INBONE(®) I to INBONE(®) II) and complete conversion (Agility(™) to INBONE(®) II, Agility(™) to Salto Talaris(®) XT, Scandinavian Total Ankle Replacement Prosthesis to Salto Talaris(®) XT). The mean radiation exposure per case was significant at 3.49 ± 2.21 mGy. Complete conversions, specifically Agility(™) to INBONE(®) II, exhibited the greatest radiation exposure and C-arm time. Revision implant selection and revision type (complete or partial) directly contributed to radiation exposure. Accordingly, revision systems requiring less radiation exposure are preferable. Surgeons should strive to minimize intraoperative complications and limit additional procedures to those necessary, because both lead to additional radiation exposure.

  13. Monitoring of radiation exposure and registration of doses

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The guide defines the concepts relevant to the monitoring of radiation exposure and working conditions and provides guidelines for determining the necessity of monitoring and subsequently organizing it. In addition, instructions are given for reporting doses to the Dose Register of the Finnish Centre for Radiation and Nuclear Safety (STUK). Also the procedures are described for situations leading to exceptional exposures. (10 refs., 1 tab.).

  14. Radiation Exposure from Medical Exams and Procedures

    Science.gov (United States)

    ... radiation (absorbed dose) or to the potential biological effect in tissue exposed to radiation (equivalent dose). Sv or Sievert The International System of Units (SI) unit for dose equivalent equal to 1 joule/kilogram. The sievert has replaced the rem; one ...

  15. Dose-effect relationship in radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Oberhausen, E.

    1983-01-01

    As criterion for the evaluation of risk in connection with nuclear accidents the diminishing of life expectance is assumed. This would allow a better weighting of the different detriments. The possible dose-effect relations for the different detriments caused by radiation are discussed. Some models for a realistic evaluation of the different radiation detriments are proposed.

  16. Radiation exposure during travelling in Malaysia.

    Science.gov (United States)

    Omar, M; Hassan, A; Sulaiman, I

    2006-01-01

    Absorbed dose rates in vehicles during travelling by different modes of transport in Malaysia were measured. Radiation levels measured on roads in Peninsular Malaysia were within a broad range, i.e. between 36 and 1560 nGy h(-1). The highest reading, recorded while travelling near monazite and zircon mineral dumps, was 13 times the mean environmental radiation level of Malaysia. It is evident that radioactive material dumps on the roadsides can influence the radiation level on the road. The absorbed dose rates measured while travelling on an ordinary train were between 60 and 350 nGy h(-1). The highest reading was measured when the train passed a tunnel built through a granite rock hill. The measurement during sea travelling by ferries gave the lowest radiation level owing to merely cosmic radiation at the sea level.

  17. Cancer risks following diagnostic and therapeutic radiation exposure in children

    Energy Technology Data Exchange (ETDEWEB)

    Kleinerman, Ruth A. [National Institutes of Health, Division of Cancer Epidemiology and Genetics, National Cancer Institute, EPS 7044, Rockville, MD (United States)

    2006-09-15

    The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life. (orig.)

  18. Radiation exposure from diagnostic imaging among patients with gastrointestinal disorders.

    LENUS (Irish Health Repository)

    Desmond, Alan N

    2012-03-01

    There are concerns about levels of radiation exposure among patients who undergo diagnostic imaging for inflammatory bowel disease (IBD), compared with other gastrointestinal (GI) disorders. We quantified imaging studies and estimated the cumulative effective dose (CED) of radiation received by patients with organic and functional GI disorders. We also identified factors and diagnoses associated with high CEDs.

  19. Serum Amyloid A as a Biomarker for Radiation Exposure.

    Science.gov (United States)

    Sproull, Mary; Kramp, Tamalee; Tandle, Anita; Shankavaram, Uma; Camphausen, Kevin

    2015-07-01

    There is a need for minimally invasive biomarkers that can accurately and quickly quantify radiation exposure. Radiation-responsive proteins have applications in clinical medicine and for mass population screenings after a nuclear or radiological incident where the level of radiation exposure and exposure pattern complicate medical triage for first responders. In this study, we evaluated the efficacy of the acute phase protein serum amyloid A (SAA) as a biomarker for radiation exposure using plasma from irradiated mice. Ten-week-old female C57BL6 mice received a 1-8 Gy single whole-body or partial-body dose from a Pantak X-ray source at a dose rate of 2.28 Gy/min. Plasma was collected by mandibular or cardiac puncture at 6, 24, 48 and 72 h or 1-3 weeks postirradiation. SAA levels were determined using a commercially available ELISA assay. Data was pooled to generate SAA μg/ml threshold values correlating plasma SAA levels with radiation dose. SAA levels were statistically significant over control at all exposures between 2 and 8 Gy at 24 h postirradiation but not at 6, 48 and 72 h or 1-3 weeks postirradiation. SAA levels at 1 Gy were not significantly elevated over control at all time points. Total-body-irradiated (TBI) SAA levels at 24 h were used to generate a dose prediction model that successfully differentiated TBI mice into dose received cohorts of control/1 Gy and ≥ 2 Gy groups with a high degree of accuracy in a blind study. Dose prediction of partial-body exposures based on the TBI model correlated increasing predictive accuracy with percentage of body exposure to radiation. Our findings indicate that plasma SAA levels might be a useful biomarker for radiation exposure in a variety of total- and partial-body irradiation settings.

  20. Low-dose radiation exposure and carcinogenesis

    National Research Council Canada - National Science Library

    Suzuki, Keiji; Yamashita, Shunichi

    2012-01-01

    .... Epidemiological studies have demonstrated the dose-response relationships for cancer induction and quantitative evaluations of cancer risk following exposure to moderate to high doses of low-linear...

  1. Compensation for damage to workers health exposed to ionizing radiation in Argentina

    CERN Document Server

    Sobehart, L J

    2003-01-01

    The objective of this report is to analyze the possibility to establish a scheme to compensate damage to workers health exposed to ionizing radiation in Argentina for those cases in which it is possible to assume that the exposure to ionizing radiation is the cause of the cancer suffered by the worker. The proposed scheme is based on the recommendations set out in the 'International Conference on Occupational Radiation Protection: Protecting Workers against Exposure to Ionization Radiation, held in Geneva, Switzerland, August 26-30, 2002. To this end, the study analyzes the present state of scientific knowledge on cancer causation due to genotoxic factors, and the accepted form of the doses-response curve, for the human beings exposure to ionization radiation at low doses with low doses rates. Finally, the labor laws and regulations related to damage compensation; in particular the present Argentine Labor Law; the National Russian Federal Occupational Radiological Health Impairment and Workmen Compensation, t...

  2. Natural and anthropogenic radiation exposure of humans in Germany; Natuerliche und zivilisatorische Strahlenexposition des Menschen in Deutschland

    Energy Technology Data Exchange (ETDEWEB)

    Koelzer, Winfried

    2016-12-15

    The contribution on natural and anthropogenic radiation exposure in Germany covers the following issues: (1) natural radiation exposure: external radiation exposure - cosmic and terrestric radiation, internal radiation exposure - primordial and cosmogenic radionuclides; radiation exposure due to sola neutrinos and geo-neutrinos. (2) Anthropogenic radiation exposure: radiation exposure in medicine, radioactivity in industrial products, radiation exposure during flights, radiation exposure due to nuclear facilities, radiation exposure due to fossil energy carriers in power generation, radiation exposure due to nuclear explosions, radiation exposure due to nuclear accidents. (3) Occupational radiation exposure in Germany: radiation monitoring with personal dosimeters in medicine and industry, dose surveillance of the aviation personal, working places with increases radiation exposure by natural radiation sources.

  3. Operational Prototype Development of a Global Aircraft Radiation Exposure Nowcast

    Science.gov (United States)

    Mertens, Christopher; Kress, Brian; Wiltberger, Michael; Tobiska, W. Kent; Bouwer, Dave

    Galactic cosmic rays (GCR) and solar energetic particles (SEP) are the primary sources of human exposure to high linear energy transfer (LET) radiation in the atmosphere. High-LET radiation is effective at directly breaking DNA strands in biological tissue, or producing chemically active radicals in tissue that alter the cell function, both of which can lead to cancer or other adverse health effects. A prototype operational nowcast model of air-crew radiation exposure is currently under development and funded by NASA. The model predicts air-crew radiation exposure levels from both GCR and SEP that may accompany solar storms. The new air-crew radiation exposure model is called the Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model. NAIRAS will provide global, data-driven, real-time exposure predictions of biologically harmful radiation at aviation altitudes. Observations are utilized from the ground (neutron monitors), from the atmosphere (the NCEP Global Forecast System), and from space (NASA/ACE and NOAA/GOES). Atmospheric observations characterize the overhead mass shielding and the ground-and space-based observations provide boundary conditions on the incident GCR and SEP particle flux distributions for transport and dosimetry calculations. Radiation exposure rates are calculated using the NASA physics-based HZETRN (High Charge (Z) and Energy TRaNsport) code. An overview of the NAIRAS model is given: the concept, design, prototype implementation status, data access, and example results. Issues encountered thus far and known and/or anticipated hurdles to research to operations transition are also discussed.

  4. Radiation aging of stockpile and space-based microelectronics.

    Energy Technology Data Exchange (ETDEWEB)

    Hembree, Charles Edward; Hjalmarson, Harold Paul

    2004-02-01

    This report describes an LDRD-supported experimental-theoretical collaboration on the enhanced low-dose-rate sensitivity (ELDRS) problem. The experimental work led to a method for elimination of ELDRS, and the theoretical work led to a suite of bimolecular mechanisms that explain ELDRS and is in good agreement with various ELDRS experiments. The model shows that the radiation effects are linear in the limit of very low dose rates. In this limit, the regime of most concern, the model provides a good estimate of the worst-case effects of low dose rate ionizing radiation.

  5. Health Impacts from Acute Radiation Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J.

    2003-09-30

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

  6. Heavy ion radiobiology for hadrontherapy and space radiation protection.

    Science.gov (United States)

    Durante, Marco

    2004-12-01

    Research in the field of biological effects of heavy charged particles is needed for both heavy-ion therapy (hadrontherapy) and protection from the exposure to galactic cosmic radiation in long-term manned space missions. Although the exposure conditions (e.g. high- vs. low-dose rate) and relevant endpoints (e.g. cell killing vs. neoplastic transformation) are different in the two fields, it is clear that a substantial overlap exists in several research topics. Three such topics are discussed in this short review: individual radiosensitivity, mixed radiation fields, and late stochastic effects of heavy ions. In addition, researchers involved either in experimental studies on space radiation protection or heavy-ion therapy will basically use the same accelerator facilities. It seems to be important that novel accelerator facilities planned (or under construction) for heavy-ion therapy reserve a substantial amount of beamtime to basic studies of heavy-ion radiobiology and its applications in space radiation research.

  7. Preparation and determination of kerma for Iridium 192 sources of low dose rate for brachytherapy; Preparacion y determinacion del kerma de fuentes de iridio-192 de baja tasa de dosis para braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Tendilla, J.I.; Tovar M, V.; Mitsoura, E.; Aguilar H, F.; Alanis M, J. [Instituto Nacional de Investigaciones Nucleares, C.P. 52045-1, Salazar, Esrado de Mexico, D.F. (Mexico)

    2000-07-01

    The practice of Brachytherapy with Iridium-192 sources of low dose rate (0.4 - 0.8 Gy/h) is a technique used in the treatment of diverse illnesses. in this work the preparation, quality control and calibration are presented in terms of kerma in air of Iridium-192 using as target these recycled Iridium-Platinum wires. The targets were obtained as decayed sources of different radio therapeutical centers in the country and they were characterized by Scanning electron microscopy in order to determine their chemical composition. Subsequently it was developed an experimental design to establish the effect of neutron flux, geometrical array and irradiation time over the activity and percentage of the sources homogeneity. The homogeneity was determined by auto radiography and by Gamma spectroscopy. Once the optimal irradiation conditions were established, it is determined the apparent activity and kerma in air using a well type ionization chamber with traceability to a primary laboratory. Iridium-192 sources were obtained with an average homogeneity 96 %, apparent activity 282.129 {+-} 0.531 M Bq and kerma in air 0.03200 {+-} 0.00006 m Gy m/h A. (Author)

  8. 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.

  9. 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.

  10. Naturally occurring radiation sources: existing or planned exposure situation?

    Energy Technology Data Exchange (ETDEWEB)

    Hedemann-Jensen, Per [Danish Decommissioning, DK-4000 Roskilde (Denmark)

    2010-12-01

    After more than fifteen years of application, ICRP Publication 60 has been revised. The revision was based upon the concept of 'controllable dose' as the dose or sum of doses to an individual from a particular source that can reasonably be controlled by whatever means. The new recommendations have been published as ICRP Publication 103. The European Basic Safety Standards as well as the International Basic Safety Standards are currently under revision as a result of the new recommendations from ICRP. According to the ICRP, there have been indications that some changes to the structure and terminology of the system of protection were desirable in order to improve clarity and utility. In particular the distinction between practices and interventions may not have been clearly understood and the ICRP now recognises three types of exposure situations, which replace the previous categorisation into practices and interventions. These exposure situations are intended to cover the entire range of exposure situations: (1) planned exposure, (2) existing exposure and (3) emergency exposure. There are situations of exposure to naturally occurring radiation sources in different occupations, e.g. exposure to radon and radon progeny in workplaces other than where the exposure is required by or is directly related to the work and aircrew exposed to cosmic radiation. In the European (Euratom) and the International Basic Safety Standards, these exposure situations are treated conceptually different-either as a planned exposure situation or as an existing exposure situation. This note reviews the change of exposure situations from Publication 60 to Publication 103 and the implications for the revision of both the International and the European Basic Safety Standards. The paper draws some conclusions on the classification of the exposure situations in the two basic safety standards based on a logical interpretation of the ICRP recommendations. It is recommended that the

  11. Occupational cosmic radiation exposure and cancer in airline cabin crew.

    Energy Technology Data Exchange (ETDEWEB)

    Kojo, K.

    2013-03-15

    Cosmic radiation dose rates are considerably higher at cruising altitudes of airplanes than at ground level. Previous studies have found increased risk of certain cancers among aircraft cabin crew, but the results are not consistent across different studies. Despite individual cosmic radiation exposure assessment is important for evaluating the relation between cosmic radiation exposure and cancer risk, only few previous studies have tried to develop an exposure assessment method. The evidence for adverse health effects in aircrews due to ionizing radiation is inconclusive because quantitative dose estimates have not been used. No information on possible confounders has been collected. For an occupational group with an increased risk of certain cancers it is very important to assess if the risk is related to occupational exposure. The goal of this thesis was to develop two separate retrospective exposure assessment methods for occupational exposure to cosmic radiation. The methods included the assessment based on survey on flight histories and based on company flight timetables. Another goal was to describe the cancer incidence among aircraft cabin crew with a large cohort in four Nordic countries, i.e., Finland, Iceland, Norway, and Sweden. Also the contribution of occupational as well as non-occupational factors to breast and skin cancer risk among the cabin crew was studied with case-control studies. Using the survey method of cosmic radiation exposure assessment, the median annual radiation dose of Finnish airline cabin crew was 0.6 milliSievert (mSv) in the 1960s, 3.3 mSv in the 1970s, and 3.6 mSv in the 1980s. With the flight timetable method, the annual radiation dose increased with time being 0.7 mSv in the 1960 and 2.1 mSv in the 1995. With the survey method, the median career dose was 27.9 mSv and with the timetable method 20.8 mSv. These methods provide improved means for individual cosmic radiation exposure assessment compared to studies where cruder

  12. Cumulative radiation exposure in children with cystic fibrosis.

    LENUS (Irish Health Repository)

    O'Reilly, R

    2010-02-01

    This retrospective study calculated the cumulative radiation dose for children with cystic fibrosis (CF) attending a tertiary CF centre. Information on 77 children with a mean age of 9.5 years, a follow up time of 658 person years and 1757 studies including 1485 chest radiographs, 215 abdominal radiographs and 57 computed tomography (CT) scans, of which 51 were thoracic CT scans, were analysed. The average cumulative radiation dose was 6.2 (0.04-25) mSv per CF patient. Cumulative radiation dose increased with increasing age and number of CT scans and was greater in children who presented with meconium ileus. No correlation was identified between cumulative radiation dose and either lung function or patient microbiology cultures. Radiation carries a risk of malignancy and children are particularly susceptible. Every effort must be made to avoid unnecessary radiation exposure in these patients whose life expectancy is increasing.

  13. Use of a radiopaque localizer grid to reduce radiation exposure

    Directory of Open Access Journals (Sweden)

    Li Wentao

    2011-08-01

    Full Text Available Abstract Background Minimally invasive spine surgery requires placement of the skin incision at an ideal location in the patient's back by the surgeon. However, numerous fluoroscopic x-ray images are sometimes required to find the site of entry, thereby exposing patients and Operating Room personnel to additional radiation. To minimize this exposure, a radiopaque localizer grid was devised to increase planning efficiency and reduce radiation exposure. Results The radiopaque localizer grid was utilized to plan the point of entry for minimally invasive spine surgery. Use of the grid allowed the surgeon to accurately pinpoint the ideal entry point for the procedure with just one or two fluoroscopic X-ray images. Conclusions The reusable localizer grid is a simple and practical device that may be utilized to more efficiently plan an entry site on the skin, thus reducing radiation exposure. This device or a modified version may be utilized for any procedure involving the spine.

  14. Biomarkers of Alpha Particle Radiation Exposure

    Science.gov (United States)

    2014-04-01

    identified strong responding genes at each of the individual doses tested. Among these genes, 31 were common to all doses with high expression levels...bead array technology. The gene expression profiles were compared to non-irradiated controls. Strong dose-responsive genes were then further...SH, Banath JP, Yu TY, Chu EHM , Lambur H, Olive PL. (2003). Expression of phosphorylated histone H2AX in cultured cell lines following exposure to X

  15. Development of a predictive code for aircrew radiation exposure (PCAIRE)

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, B.J.; Bennett, L.G.I.; Green, A.R.; McCall, M.J.; Ellaschuk, B.; Pierre, M.; Butler, A.; Desormeaux, M. [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada)

    2003-07-01

    Jet aircrew are routinely exposed to levels of natural background radiation (i.e., galactic cosmic radiation) that are significantly higher than those present at ground level. This paper describes the method of collecting and analyzing radiation data from numerous worldwide flights, and the encapsulation of these results into a computer code (PCAIRE) for the prediction of the aircrew radiation exposure on any flight in the world at any period in the solar cycle. Predictions from the PCAIRE code were then compared to integral doses measured at commercial altitudes during experimental flights made by various research groups over the past five years over the given solar cycle. In general, the code predictions are in agreement with the measured data within {+-} 20%. An additional correlation has been developed for estimation of aircrew exposure resulting from solar particle events. (author)

  16. State Register of Sources of Ionizing Radiation and Occupational exposure

    CERN Document Server

    2002-01-01

    One of main tasks of Radiation Protection Centre is to collect, process, systematize, store and provide the data on sources of ionizing radiation and occupational exposures. The number of sources in 2002 is provided and compared with previous year. Distribution of workers according to the type of practice is compared with previous year. Distribution of sealed sources and x-ray machines according their use is presented.

  17. Approximating the Probability of Mortality Due to Protracted Radiation Exposures

    Science.gov (United States)

    2016-06-01

    Assessment for Human Response and Health Effects contract, DTRA-01-03-D-0014-0015, under Mr. Eric Nelson at NTMP. That contract included a wide-range of...syndrome of acute radiation sickness. In the MARCELL model, radiation exposure dynamically depletes the bone marrow cell population , the underpinning of...cell population nadir (maximum cytopenia) as the protracted dose in question. This EPD is used in conjunction with a lognormal, dose-response curve

  18. [Adaptive changes in the body upon exposure to electromagnetic radiation].

    Science.gov (United States)

    Zubkova, S M

    1996-01-01

    The chance to use electromagnetic exposures as active adaptogen and the detecting of adaptive changes following them were objects of our studies. The data of experimental and clinical studies significative the dependence of changes on the functional state of organism were seen. Particular attention is paid to the site of exposure and to the advantages in the action of electromagnetic exposures on areas overlaying the endocrine glands and control centers of central nerve system. In these conditions electromagnetic exposures play a part of trigger initiated natural processes of homeostatic regulation in the organism functional systems. It is shown that the course of electromagnetic exposures in wide frequency range until laser radiation (infrared and red) arises adaptive changes of the regulator systems, of the bioenergetic and the biosynthetic processes in myocardium, liver, brain, thymus and other tissues predetermined genetically and secured the power of the adaptive systems. The cross-adaptation effects underlie the electromagnetic exposures medical action.

  19. Evaluation of medical radiation exposure in pediatric interventional radiology procedures

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, Valeria Coelho Costa; Navarro, Marcus Vinicius Teixeira; Oliveira, Aline da Silva Pacheco, E-mail: vccnavarro@gmail.com [Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia (IFBA), Salvador, BA (Brazil); Maia, Ana Figueiredo [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Oliveira, Adriano Dias Dourado [Sociedade Brasileira de Hemodinamica e Cardiologia Intervencionista, Salvador, BA (Brazil)

    2012-07-15

    Objective: To evaluate pediatric radiation exposure in procedures of interventional radiology in two hospitals in the Bahia state, aiming at contributing to delineate the scenario at the state and national levels. The knowledge of exposure levels will allow an evaluation of the necessity of doses optimization, considering that peculiarities of radiology and pediatrics become even more significant in interventional radiology procedures which involve exposure to higher radiation doses. Materials and Methods: A total of 32 procedures were evaluated in four rooms of the two main hospitals performing pediatric interventional radiology procedures in the Bahia state. Air kerma rate and kerma-area product were evaluated in 27 interventional cardiac and 5 interventional brain procedures. Results: Maximum values for air kerma rate and kerma-area product and air kerma obtained in cardiac procedures were, respectively, 129.9 Gy.cm{sup 2} and 947.0 mGy; and, for brain procedures were 83.3 Gy.cm{sup 2} and 961.0 mGy. Conclusion: The present study results showed exposure values up to 14 times higher than those found in other foreign studies, and approximating those found for procedures in adults. Such results demonstrate excessive exposure to radiation, indicating the need for constant procedures optimization and evaluation of exposure rates. (author)

  20. Reduced exposure to microwave radiation by rats: frequency specific effects

    Energy Technology Data Exchange (ETDEWEB)

    D' Andrea, J.A.; DeWitt, J.R.; Portuguez, L.M.; Gandhi, O.P.

    1988-01-01

    Previous research has shown that SAR hotspots are induced within the laboratory rat and that the resulting thermal hotspots are not entirely dissipated by bloodflow. Two experiments were conducted to determine if hotspot formation in the body and tail of the rat, which is radiation frequency specific, would have behavioral consequences. In the first experiment rats were placed in a plexiglas cage one side of which, when occupied by the rat, commenced microwave radiation exposure; occupancy of the other side terminated exposure. Groups of rats were tested during a baseline period to determine the naturally preferred side of the cage. Subsequent exposure to 360-MHz, 700-MHz or 2450-MHz microwave radiation was made contingent on preferred-side occupancy. A significant reduction in occupancy of the preferred side of the cage, and hence, microwaves subsequently occurred. Reduced exposure to 360-MHz and 2450-MHz microwaves at 1, 2, 6 and 10 W/kg were significantly different from 700-MHz microwaves. In the second experiment semichronic exposures revealed the threshold for reduced exposure of 2450-MHz microwaves to be located between whole-body SAR's of 2.1 and 2.8 W/kg.

  1. Protection of DNA damage by radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Ho; Kim, In Gyu; Lee, Kang Suk; Kim, Kug Chan; Oh, Tae Jung

    1998-12-01

    The SOS response of Escherichia coli is positively regulated by RecA. To examine the effects of polyamines on The SOS response of E. Coli, we investigated the expression of recA gene in polyamine-deficient mutant and wild type carrying recA'::lacZ fusion gene. As a result, recA expression by mitomycin C is higher in wild type than that of polyamine-deficient mutant, but recA expression by UV radiation is higher in wild type than of mutant. We also found that exogenous polyamines restored the recA expression in the polyamine-deficient mutant to the wild type level. These results proposed that polyamines play an important role in mechanism of intracellular DNA protection by DNA damaging agents.

  2. Radiation Exposure of Abdominal Cone Beam Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Sailer, Anna M., E-mail: anni.sailer@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Schurink, Geert Willem H., E-mail: gwh.schurink@mumc.nl [Maastricht University Medical Centre, Department of Surgery (Netherlands); Wildberger, Joachim E., E-mail: j.wildberger@mumc.nl; Graaf, Rick de, E-mail: r.de.graaf@mumc.nl; Zwam, Willem H. van, E-mail: w.van.zwam@mumc.nl; Haan, Michiel W. de, E-mail: m.de.haan@mumc.nl; Kemerink, Gerrit J., E-mail: gerrit.kemerink@mumc.nl; Jeukens, Cécile R. L. P. N., E-mail: cecile.jeukens@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands)

    2015-02-15

    PurposeTo evaluate patients radiation exposure of abdominal C-arm cone beam computed tomography (CBCT).MethodsThis prospective study was approved by the institutional review board; written, informed consent was waived. Radiation exposure of abdominal CBCT was evaluated in 40 patients who underwent CBCT during endovascular interventions. Dose area product (DAP) of CBCT was documented and effective dose (ED) was estimated based on organ doses using dedicated Monte Carlo simulation software with consideration of X-ray field location and patients’ individual body weight and height. Weight-dependent ED per DAP conversion factors were calculated. CBCT radiation dose was compared to radiation dose of procedural fluoroscopy. CBCT dose-related risk for cancer was assessed.ResultsMean ED of abdominal CBCT was 4.3 mSv (95 % confidence interval [CI] 3.9; 4.8 mSv, range 1.1–7.4 mSv). ED was significantly higher in the upper than in the lower abdomen (p = 0.003) and increased with patients’ weight (r = 0.55, slope = 0.045 mSv/kg, p < 0.001). Radiation exposure of CBCT corresponded to the radiation exposure of on average 7.2 fluoroscopy minutes (95 % CI 5.5; 8.8 min) in the same region of interest. Lifetime risk of exposure related cancer death was 0.033 % or less depending on age and weight.ConclusionsMean ED of abdominal CBCT was 4.3 mSv depending on X-ray field location and body weight.

  3. Radiation exposure of U.S. military individuals.

    Science.gov (United States)

    Blake, Paul K; Komp, Gregory R

    2014-02-01

    The U.S. military consists of five armed services: the Army, Navy, Marine Corps, Air Force, and Coast Guard. It directly employs 1.4 million active duty military, 1.3 million National Guard and reserve military, and 700,000 civilian individuals. This paper describes the military guidance used to preserve and maintain the health of military personnel while they accomplish necessary and purposeful work in areas where they are exposed to radiation. It also discusses military exposure cohorts and associated radiogenic disease compensation programs administered by the U.S. Department of Veterans Affairs, the U.S. Department of Justice, and the U.S. Department of Labor. With a few exceptions, the U.S. military has effectively employed ionizing radiation since it was first introduced during the Spanish-American War in 1898. The U.S military annually monitors 70,000 individuals for occupational radiation exposure: ~2% of its workforce. In recent years, the Departments of the Navy (including the Marine Corps), the Army, and the Air Force all have a low collective dose that remains close to 1 person-Sv annually. Only a few Coast Guard individuals are now routinely monitored for radiation exposure. As with the nuclear industry as a whole, the Naval Reactors program has a higher collective dose than the remainder of the U.S. military. The U.S. military maintains occupational radiation exposure records on over two million individuals from 1945 through the present. These records are controlled in accordance with the Privacy Act of 1974 but are available to affected individuals or their designees and other groups performing sanctioned epidemiology studies.Introduction of Radiation Exposure of U.S. Military Individuals (Video 2:19, http://links.lww.com/HP/A30).

  4. 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.

  5. Dose and dose-rate effects of ionizing radiation: a discussion in the light of radiological protection

    Energy Technology Data Exchange (ETDEWEB)

    Ruehm, Werner [Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Institute of Radiation Protection, Neuherberg (Germany); Woloschak, Gayle E. [Northwestern University, Department of Radiation Oncology, Feinberg School of Medicine, Chicago, IL (United States); Shore, Roy E. [Radiation Effects Research Foundation (RERF), Hiroshima City (Japan); Azizova, Tamara V. [Southern Urals Biophysics Institute (SUBI), Ozyorsk, Chelyabinsk Region (Russian Federation); Grosche, Bernd [Federal Office for Radiation Protection, Oberschleissheim (Germany); Niwa, Ohtsura [Fukushima Medical University, Fukushima (Japan); Akiba, Suminori [Kagoshima University Graduate School of Medical and Dental Sciences, Department of Epidemiology and Preventive Medicine, Kagoshima City (Japan); Ono, Tetsuya [Institute for Environmental Sciences, Rokkasho, Aomori-ken (Japan); Suzuki, Keiji [Nagasaki University, Department of Radiation Medical Sciences, Atomic Bomb Disease Institute, Nagasaki (Japan); Iwasaki, Toshiyasu [Central Research Institute of Electric Power Industry (CRIEPI), Radiation Safety Research Center, Nuclear Technology Research Laboratory, Tokyo (Japan); Ban, Nobuhiko [Tokyo Healthcare University, Faculty of Nursing, Tokyo (Japan); Kai, Michiaki [Oita University of Nursing and Health Sciences, Department of Environmental Health Science, Oita (Japan); Clement, Christopher H.; Hamada, Nobuyuki [International Commission on Radiological Protection (ICRP), PO Box 1046, Ottawa, ON (Canada); Bouffler, Simon [Public Health England (PHE), Centre for Radiation, Chemical and Environmental Hazards, Chilton, Didcot (United Kingdom); Toma, Hideki [JAPAN NUS Co., Ltd. (JANUS), Tokyo (Japan)

    2015-11-15

    The biological effects on humans of low-dose and low-dose-rate exposures to ionizing radiation have always been of major interest. The most recent concept as suggested by the International Commission on Radiological Protection (ICRP) is to extrapolate existing epidemiological data at high doses and dose rates down to low doses and low dose rates relevant to radiological protection, using the so-called dose and dose-rate effectiveness factor (DDREF). The present paper summarizes what was presented and discussed by experts from ICRP and Japan at a dedicated workshop on this topic held in May 2015 in Kyoto, Japan. This paper describes the historical development of the DDREF concept in light of emerging scientific evidence on dose and dose-rate effects, summarizes the conclusions recently drawn by a number of international organizations (e.g., BEIR VII, ICRP, SSK, UNSCEAR, and WHO), mentions current scientific efforts to obtain more data on low-dose and low-dose-rate effects at molecular, cellular, animal and human levels, and discusses future options that could be useful to improve and optimize the DDREF concept for the purpose of radiological protection. (orig.)

  6. Modelling of aircrew radiation exposure during solar particle events

    Science.gov (United States)

    Al Anid, Hani Khaled

    In 1990, the International Commission on Radiological Protection recognized the occupational exposure of aircrew to cosmic radiation. In Canada, a Commercial and Business Aviation Advisory Circular was issued by Transport Canada suggesting that action should be taken to manage such exposure. In anticipation of possible regulations on exposure of Canadian-based aircrew in the near future, an extensive study was carried out at the Royal Military College of Canada to measure the radiation exposure during commercial flights. The radiation exposure to aircrew is a result of a complex mixed-radiation field resulting from Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs). Supernova explosions and active galactic nuclei are responsible for GCRs which consist of 90% protons, 9% alpha particles, and 1% heavy nuclei. While they have a fairly constant fluence rate, their interaction with the magnetic field of the Earth varies throughout the solar cycles, which has a period of approximately 11 years. SEPs are highly sporadic events that are associated with solar flares and coronal mass ejections. This type of exposure may be of concern to certain aircrew members, such as pregnant flight crew, for which the annual effective dose is limited to 1 mSv over the remainder of the pregnancy. The composition of SEPs is very similar to GCRs, in that they consist of mostly protons, some alpha particles and a few heavy nuclei, but with a softer energy spectrum. An additional factor when analysing SEPs is the effect of flare anisotropy. This refers to the way charged particles are transported through the Earth's magnetosphere in an anisotropic fashion. Solar flares that are fairly isotropic produce a uniform radiation exposure for areas that have similar geomagnetic shielding, while highly anisotropic events produce variable exposures at different locations on the Earth. Studies of neutron monitor count rates from detectors sharing similar geomagnetic shielding properties

  7. DOE Radiation Exposure Monitoring System (REMS) Data Update

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Nimi; Hagemeyer, Derek

    2012-05-05

    This slide show presents the 2011 draft data for DOE occupational radiation exposure.Clarification is given on Reporting Data regarding: reporting Total Organ Dose (TOD); reporting Total Skin Dose (TSD), and Total Extremity Dose (TExD) ; and Special individuals reporting.

  8. Radiation Exposure Alters Expression of Metabolic Enzyme Genes in Mice

    Science.gov (United States)

    Wotring, V. E.; Mangala, L. S.; Zhang, Y.; Wu, H.

    2011-01-01

    Most administered pharmaceuticals are metabolized by the liver. The health of the liver, especially the rate of its metabolic enzymes, determines the concentration of circulating drugs as well as the duration of their efficacy. Most pharmaceuticals are metabolized by the liver, and clinically-used medication doses are given with normal liver function in mind. A drug overdose can result in the case of a liver that is damaged and removing pharmaceuticals from the circulation at a rate slower than normal. Alternatively, if liver function is elevated and removing drugs from the system more quickly than usual, it would be as if too little drug had been given for effective treatment. Because of the importance of the liver in drug metabolism, we want to understand the effects of spaceflight on the enzymes of the liver and exposure to cosmic radiation is one aspect of spaceflight that can be modeled in ground experiments. Additionally, it has been previous noted that pre-exposure to small radiation doses seems to confer protection against later and larger radiation doses. This protective power of pre-exposure has been called a priming effect or radioadaptation. This study is an effort to examine the drug metabolizing effects of radioadaptation mechanisms that may be triggered by early exposure to low radiation doses.

  9. Characterization and simulation of hourly exposure series of global radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mora-Lopez, L. [Universidad de Malaga (Spain). Dpto. Lenguajes y C. Computacion; Sidrach-de-Cardona, M. [Universidad de Malaga (Spain). Dpto. Fisica Aplicada

    1997-06-01

    A statistical model which captures the main features of hourly exposure series of global radiation is proposed. This model is used to obtain a procedure to generate radiation series without imposing, a priori, any restriction on the form of the probability distribution function of the series. The statistical model was taken from the stationary stochastic processes theory. Data were obtained from ten different Spanish locations. As monthly hourly exposure series of global radiation are not stationary, they are modified in order to remove the observed trends. A multiplicative autoregressive moving average model with regular and seasonal components was used. It is statistically accepted that this is the true model which generates most of the analyzed sequences. However, the underlying parameters of the model vary from one location to another and from one month to another. Therefore, it is necessary to examine further the relationship between the parameters of the model and the available data from most locations. (author)

  10. Low Dose Gamma Irradiation Potentiates Secondary Exposure to Gamma Rays or Protons in Thyroid Tissue Analogs

    Energy Technology Data Exchange (ETDEWEB)

    Green, Lora M

    2006-05-25

    We have utilized our unique bioreactor model to produce three-dimensional thyroid tissue analogs that we believe better represent the effects of radiation in vivo than two-dimensional cultures. Our thyroid model has been characterized at multiple levels, including: cell-cell exchanges (bystander), signal transduction, functional changes and modulation of gene expression. We have significant preliminary data on structural, functional, signal transduction and gene expression responses from acute exposures at high doses (50-1000 rads) of gamma, protons and iron (Green et al., 2001a; 2001b; 2002a; 2002b; 2005). More recently, we used our DOE funding (ending Feb 06) to characterize the pattern of radiation modulated gene expression in rat thyroid tissue analogs using low-dose/low-dose rate radiation, plus/minus acute challenge exposures. Findings from these studies show that the low-dose/low-dose rate “priming” exposures to radiation invoked changes in gene expression profiles that varied with dose and time. The thyrocytes transitioned to a “primed” state, so that when the tissue analogs were challenged with an acute exposure to radiation they had a muted response (or an increased resistance) to cytopathological changes relative to “un-primed” cells. We measured dramatic differences in the primed tissue analogs, showing that our original hypothesis was correct: that low dose gamma irradiation will potentiate the repair/adaptation response to a secondary exposure. Implications from these findings are that risk assessments based on classical in vitro tissue culture assays will overestimate risk, and that low dose rate priming results in a reduced response in gene expression to a secondary challenge exposure, which implies that a priming dose provides enhanced protection to thyroid cells grown as tissue analogs. If we can determine that the effects of radiation on our tissue analogs more closely resemble the effects of radiation in vivo, then we can better

  11. Prediction of aircrew radiation exposure during solar particle events

    Science.gov (United States)

    Bennett, Les

    A transport code analysis using the Monte Carlo code MCNPX is used to propagate an extrapolated particle spectrum based on GOES satellite measurements through the atmosphere to estimate aircrew radiation exposure for solar particle events. Comparison between code predictions and actual flight measurements made during ground level event (GLE) 60 and 65 are presented. Data from ground-level neutron monitoring stations around the world are also compared against the model predictions for various events. A computer code has been further developed implementing this methodology for routine aircrew exposure estimation from solar particle events to supplement those predictions from galactic cosmic radiation using the PCAIRE code in order to better determine the overall aircrew exposure at altitude.

  12. [beta-Radiation exposure with (188)Re-labelled pharmaceuticals].

    Science.gov (United States)

    Andreeff, M; Wunderlich, G; Behge, K; Schönmuth, Th; Kotzerke, J

    2005-01-01

    The number of therapies with radiopharmaceuticals labelled with (188)Re is increasing requiring the documentation of the beta radiation exposure Hp(0.07) of the staff at all working and production sites and during the application and follow-up of the patient according to the new German Radiation Protection Law (StrlSchV). However, data for beta-radiation exposure are rare. Therefore, we determined the personal dose Hp(0.07) of the skin of the hands handling (188)Re radiopharmaceuticals to identify steps of high radiation exposure and to optimize working conditions. Thermoluminescence dosimeters (TLD 100) were fixed to the fingertips of the radiochemist, the physician and the nurse and compared to official ring dosimeters. In addition, to monitor radiation exposure continuously readable electronic beta- and gamma dosimeters EPD (Siemens) were used. At eight days in which therapies were performed these readings were evaluated. Considering one therapy with a (188)Re-labelled radiopharmaceutical the middle finger of the radiochemist (production) and the physician (application) showed a radiation burden of 894 and 664 muSv/GBq, respectively. The cumulative dose of the fingertips after eight days of therapy was 249 and 110 mSv for the radiochemist and physician, respectively. A cumulative finger dose after eight days of therapy of 17 and 38 muSv/GBq was found for physician and nurse leading to a Hp(0.07) of 3 and 6 mSv, respectively. Preparing the radiopharmaceutical labelled with 20GBq of (188)Re the reading of the personal electronic dosimeter of the radiochemist showed a gamma-dose rate Hp(10) of 55 muSv/h and a beta-dose rate Hp(0.07) of 663 muSv/h which are obviously not representative for the true radiation dose to the skin of the fingertips. During therapy with (188)Re-labelled radiopharmaceuticals the true radiation dose to the skin of the finger tips exceeds by far the readings of the official ring dosimeters as well as the continuously readable beta- and gamma

  13. Chromosome aberrations as biomarkers of radiation exposure: Modelling basic mechanisms

    Science.gov (United States)

    Ballarini, F.; Ottolenghi, A.

    The space radiation environment is a mixed field consisting of different particles having different energies, including high charge and energy (HZE) ions. Conventional measurements of absorbed doses may not be sufficient to completely characterise the radiation field and perform reliable estimates of health risks. Biological dosimetry, based on the observation of specific radiation-induced endpoints (typically chromosome aberrations), can be a helpful approach in case of monitored exposure to space radiation or other mixed fields, as well as in case of accidental exposure. Furthermore, various ratios of aberrations (e.g. dicentric chromosomes to centric rings and complex exchanges to simple exchanges) have been suggested as possible fingerprints of radiation quality, although all of them have been subjected to some criticisms. In this context a mechanistic model and a Monte Carlo code for the simulation of chromosome aberration induction were developed. The model, able to provide dose-responses for different aberrations (e.g. dicentrics, rings, fragments, translocations, insertions and other complex exchanges), was further developed to assess the dependence of various ratios of aberrations on radiation quality. The predictions of the model were compared with available data, whose experimental conditions were faithfully reproduced. Particular attention was devoted to the scoring criteria adopted in different laboratories and to possible biases introduced by interphase death and mitotic delay. This latter aspect was investigated by taking into account both metaphase data and data obtained with Premature Chromosome Condensation (PCC).

  14. Analysis of the Effect of Chronic and Low-Dose Radiation Exposure on Spermatogenic Cells of Male Large Japanese Field Mice ( Apodemus speciosus ) after the Fukushima Daiichi Nuclear Power Plant Accident.

    Science.gov (United States)

    Takino, Sachio; Yamashiro, Hideaki; Sugano, Yukou; Fujishima, Yohei; Nakata, Akifumi; Kasai, Kosuke; Hayashi, Gohei; Urushihara, Yusuke; Suzuki, Masatoshi; Shinoda, Hisashi; Miura, Tomisato; Fukumoto, Manabu

    2017-02-01

    In this study we analyzed the effect of chronic and low-dose-rate (LDR) radiation on spermatogenic cells of large Japanese field mice ( Apodemus speciosus ) after the Fukushima Daiichi Nuclear Power Plant (FNPP) accident. In March 2014, large Japanese field mice were collected from two sites located in, and one site adjacent to, the FNPP ex-evacuation zone: Tanashio, Murohara and Akogi, respectively. Testes from these animals were analyzed histologically. External dose rate from radiocesium (combined (134)Cs and (137)Cs) in these animals at the sampling sites exhibited 21 μGy/day in Tanashio, 304-365 μGy/day in Murohara and 407-447 μGy/day in Akogi. In the Akogi group, the numbers of spermatogenic cells and proliferating cell nuclear antigen (PCNA)-positive cells per seminiferous tubule were significantly higher compared to the Tanashio and Murohara groups, respectively. TUNEL-positive apoptotic cells tended to be detected at a lower level in the Murohara and Akogi groups compared to the Tanashio group. These results suggest that enhanced spermatogenesis occurred in large Japanese field mice living in and around the FNPP ex-evacuation zone. It remains to be elucidated whether this phenomenon, attributed to chronic exposure to LDR radiation, will benefit or adversely affect large Japanese field mice.

  15. M-BAND Study of Radiation-Induced Chromosome Aberrations in Human Epithelial Cells: Radiation Quality and Dose Rate Effects

    Science.gov (United States)

    Hada, Megumi; Cucinotta, Francis; Wu, Honglu

    2009-01-01

    The advantage of the multicolor banding in situ hybridization (mBAND) technique is its ability to identify both inter- (translocation to unpainted chromosomes) and intra- (inversions and deletions within a single painted chromosome) chromosome aberrations simultaneously. To study the detailed rearrangement of low- and high-LET radiation induced chromosome aberrations in human epithelial cells (CH184B5F5/M10) in vitro, we performed a series of experiments with Cs-137 gamma rays of both low and high dose rates, neutrons of low dose rate and 600 MeV/u Fe ions of high dose rate, with chromosome 3 painted with multi-binding colors. We also compared the chromosome aberrations in both 2- and 3-dimensional cell cultures. Results of these experiments revealed the highest chromosome aberration frequencies after low dose rate neutron exposures. However, detailed analysis of the radiation induced inversions revealed that all three radiation types induced a low incidence of simple inversions. Most of the inversions in gamma-ray irradiated samples were accompanied by other types of intra-chromosomal aberrations but few inversions were accompanied by inter-chromosomal aberrations. In contrast, neutrons and Fe ions induced a significant fraction of inversions that involved complex rearrangements of both inter- and intrachromosomal exchanges. The location of the breaks involved in chromosome exchanges was analyzed along the painted chromosome. The breakpoint distribution was found to be randomly localized on chromosome 3 after neutron or Fe ion exposure, whereas non-random distribution with clustering breakpoints was observed after -ray exposure. Our comparison of chromosome aberration yields between 2- and 3-dimensional cell cultures indicated a significant difference for gamma exposures, but not for Fe ion exposures. These experimental results indicated that the track structure of the radiation and the cellular/chromosome structure can both affect radiation-induced chromosome

  16. Lens opacities after repeated exposure to ultraviolet radiation.

    Science.gov (United States)

    Michael, R; Löfgren, S; Söderberg, P G

    1999-12-01

    To investigate the effect of the interval between two, near-threshold exposures to ultraviolet radiation (UVR) on cataract development. One eye of Sprague-Dawley rats was exposed twice to 4 kJ/m2 narrow band UVR (lambdaMAX=300 nm) for 15 min each. The interval between exposures was 0, 6, 24 or 48 h. One week after the first exposure both lenses were removed for photography and measurement of the intensity of forward light scattering to quantify lens opacities. All exposed lenses developed cataract. Forward light scattering was the same after double exposure with no interval or a 6 h interval. Forward light scattering after a 24 or 48 h interval was nearly twofold greater than that following no interval or a 6 h interval. The exposed lenses in all groups had mild anterior surface opacities and intense equatorial opacities as judged with a stereomicroscope. Two, near-threshold UVR exposures at 0 or a 6 h interval produce the same degree of lens opacification. When the second exposure follows 24 or 48 h after the first, lenticular damage increases. Repair processes between 24 and 48 h after exposure appear to be sensitive to UVR, and an additional exposure during this time may aggravate cataract development.

  17. Occupational exposure to microwave radiation in diathermia units

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, M.A.; Ubeda, A. [Hospital Ramon y Cajal, Servicio de Investigacion-BEM, Madrid (Spain); Tellez, M.; Santa Olalla, I. [Hospital La Paz, Servicio de Radiofisica y Radioproteccion, Madrid (Spain)

    2006-07-01

    The present study summarizes preliminary data addressed to complete the present knowledge on the microwave (M.V.)-exposure doses and conditions in workers exposed chronically to relatively high, though nonthermal, levels of that non ionizing radiations (N.I.R.). The obtained data are of direct application to radiation protection in occupational media provided that: 1) help to detect and eradicate practices and situations that result in overexposure; 2) they constitute a basis for the design and development of strategies for exposure control and minimization, and 3) they represent a dosimetric support necessary to properly interpret past and future epidemiologic and experimental data on potential health effects of chronic exposures to M.W. radiation at work. The described results will be extended through additional dosimetric recordings in other hospitals. The dosimetric data will be compared to the results of questionnaires among the electro-therapists working at the units studied. The objective is to identify potential relationships between exposure doses and specific diseases or level of risk perception among the investigated professional group. (authors)

  18. Study Regarding Electromagnetic Radiation Exposure Generated By Mobile Phone

    Science.gov (United States)

    Marica, Lucia; Moraru, Luminita

    2011-12-01

    Number of mobile phone users reached to 5 billion subscribers in 2010 [ABI Research, 2010]. A large number of studies illustrated the public concern about adverse effects of mobile phone radiation and possible health hazards. Position of mobile phone use in close proximity to the head leads the main radiation between the hand and the head. Many investigations studying the possible effects of mobile phone exposure, founded no measurable effects of short-term mobile phone radiation, and there was no evidence for the ability to perceive mobile phone EMF in the general population. In this study, field radiation measurements were performed on different brand and different models of mobile phones in active mode, using an EMF RF Radiation Field Strength Power Meter 1 MHz-8 GHz. The study was effectuated on both the 2G and 3G generations phones connected to the providers operating in the frequency range 450 MHz-1800 MHz. There were recorded values in outgoing call and SMS mode, incoming call and SMS mode. Results were compared with ICNIRP guidelines for exposure to general public.

  19. Modelling of aircrew radiation exposure during solar particle events

    Energy Technology Data Exchange (ETDEWEB)

    Al Anid, H.; Lewis, B.J.; Bennett, L.G.I. [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada); Takada, M. [National Inst. of Radiological Science, International Space Radiation Lab., anagawa, Inage-Ku, Chiba (Japan)

    2010-07-01

    A transport code analysis using the Monte Carlo N-Particle eXtended code, MCNPX, has been used to propagate an extrapolated particle spectrum based on satellite measurements through the atmosphere to estimate radiation exposure during solar storms at high altitudes. Neutron monitor count rate data from stations around the world were used to benchmark the model calculations during a Ground Level Event. A comparison was made between the model predictions and actual flight measurements taken with various types of instruments used to measure the mixed radiation field during GLE 60. A computer-code has been developed to implement the model for routine analysis. (author)

  20. Modelling of aircrew radiation exposure during solar particle events

    Energy Technology Data Exchange (ETDEWEB)

    Al Anid, H.; Lewis, B.J.; Bennett, L.G.I. [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada); Takada, M. [National Inst. of Radiological Science, International Space Radiation Lab., Anagawa, Inage-Ku, Chiba (Japan)

    2011-03-15

    A transport code analysis using the Monte Carlo N-Particle eXtended code, MCNPX, has been used to propagate an extrapolated particle spectrum based on satellite measurements through the atmosphere to estimate radiation exposure during solar storms at high altitudes. Neutron monitor count rate data from stations around the world were used to benchmark the model calculations during a Ground Level Event. A comparison was made between the model predictions and actual flight measurements taken with various types of instruments used to measure the mixed radiation field during GLE 60. A computer-code has been developed to implement the model for routine analysis. (author)

  1. Modelling of aircrew radiation exposure from solar particle events

    Energy Technology Data Exchange (ETDEWEB)

    Al Anid, H.; Lewis, B.J.; Bennett, L.G.I. [Royal Military College of Canada, Dept. of Chemistry and Chemical Engineering, Kingston, Ontario (Canada)

    2008-07-01

    A transport code analysis using the Monte Carlo code, MCNPX, has been used to propagate an extrapolated particle spectrum based on GOES satellite measurements through the atmosphere to estimate aircrew radiation exposure due to solar particle events. Neutron monitor count rate data from ground stations around the world were used to benchmark the model calculations during several Ground Level Events (GLEs). In addition, a comparison was made between the model predictions and actual flight measurements made by some European investigators with various types of instrument used to measure the mixed radiation field during GLE 60 and 65. A computer-code has been further developed to implement the model for routine analysis. (author)

  2. Radiation effects and ageing characteristics of bipolar junction transistors subjected to high and low dose rate total dose irradiations%双极晶体管不同剂量率的辐射效应和退火特性

    Institute of Scientific and Technical Information of China (English)

    陆妩; 余学锋; 任迪远; 艾尔肯; 郭旗

    2005-01-01

    对不同类型和型号的国产及进口双极晶体管的不同剂量率的辐照效应及退火特性进行了研究.结果表明:在辐照的剂量率范围内,无论是国产还是进口的双极晶体管,都有明显的低剂量率辐照损伤增强现象,且NPN管比PNP管的明显.文中对引起双极器件辐照损伤差异的机理进行了探讨.

  3. The low dose rate radiation response of NPN bipolar transistors under different bias%不同偏置对NPN双极晶体管的低剂量率电离辐照损伤的影响

    Institute of Scientific and Technical Information of China (English)

    费武雄; 兰博; 崔江维; 赵云; 陆妩; 任迪远; 郑玉展; 王义元; 陈睿; 王志宽; 杨永晖; 李茂顺

    2010-01-01

    对NPN双极晶体管进行了低剂剂率下不同偏置条件的电离辐射实验.结果表明,不同偏置条件下的低剂量率辐射损伤具有明显差异.基一射结反向偏置时,其过剩基极电流最大,电流增益衰减最为显著.而基射结正向偏置时,过剩基极电流和电流增益衰减郜最小.讨论了出现这种结果的内在机制.

  4. The Enhanced Effects of Low Dose Rate Radiation damage of Bipolar Transistors%双极晶体管的低剂量率辐射损伤增强效应

    Institute of Scientific and Technical Information of China (English)

    尹雪梅; 李斌; 师谦

    2007-01-01

    在辐射的剂量率范围内,无论是国产还是进1:21的双极晶体管,都有明显的低剂量率辐照损伤增强现象,且纵向NPN管比PNP管严重.本文对引起双极器件辐照损伤差异的机理进行了探讨,并讨论了双极器件的抗辐射加固技术.

  5. Overview of DOE Radiation Exposure Information Reporting System (REIRS)

    Energy Technology Data Exchange (ETDEWEB)

    Fix, J.J.; Briscoe, G.J.; Selby, J.M.; Vallario, E.J.

    1981-05-01

    The purpose of the study is to determine the adequacy of the present system, identify any necessary short-term improvements and propose feasible alternatives for an improved system. The study includes topical reports as follows: current Personnel Dosimetry Practices at DOE Facilities; overview of DOE Radiation Exposure Information Reporting System (REIRS); and alternatives to Provide Upgraded Occupational Exposure Record System. This study constitutes the second report and was a joint effort between Battelle Northwest and EG and G, Idaho Falls. EG and G has been responsible for the respository since the fall of 1978.

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

    Energy Technology Data Exchange (ETDEWEB)

    Fabrikant, J.I.

    1981-05-01

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

  7. Prenatal radiation exposure. Dose calculation; Praenatale Strahlenexposition. Dosisermittlung

    Energy Technology Data Exchange (ETDEWEB)

    Scharwaechter, C.; Schwartz, C.A.; Haage, P. [University Hospital Witten/Herdecke, Wuppertal (Germany). Dept. of Diagnostic and Interventional Radiology; Roeser, A. [University Hospital Witten/Herdecke, Wuppertal (Germany). Dept. of Radiotherapy and Radio-Oncology

    2015-05-15

    The unborn child requires special protection. In this context, the indication for an X-ray examination is to be checked critically. If thereupon radiation of the lower abdomen including the uterus cannot be avoided, the examination should be postponed until the end of pregnancy or alternative examination techniques should be considered. Under certain circumstances, either accidental or in unavoidable cases after a thorough risk assessment, radiation exposure of the unborn may take place. In some of these cases an expert radiation hygiene consultation may be required. This consultation should comprise the expected risks for the unborn while not perturbing the mother or the involved medical staff. For the risk assessment in case of an in-utero X-ray exposition deterministic damages with a defined threshold dose are distinguished from stochastic damages without a definable threshold dose. The occurrence of deterministic damages depends on the dose and the developmental stage of the unborn at the time of radiation. To calculate the risks of an in-utero radiation exposure a three-stage concept is commonly applied. Depending on the amount of radiation, the radiation dose is either estimated, roughly calculated using standard tables or, in critical cases, accurately calculated based on the individual event. The complexity of the calculation thereby increases from stage to stage. An estimation based on stage one is easily feasible whereas calculations based on stages two and especially three are more complex and often necessitate execution by specialists. This article demonstrates in detail the risks for the unborn child pertaining to its developmental phase and explains the three-stage concept as an evaluation scheme. It should be noted, that all risk estimations are subject to considerable uncertainties.

  8. Controlling and monitoring exposure to radiation from medical imaging.

    Science.gov (United States)

    2014-07-01

    Above a certain threshold dose, ionising radiation invariably provokes harmful effects such as burns, nausea and aplasia. Their severity increases with the dose received. There is no known threshold dose below which long-term harmful effects, such as cancer and genetic defects, do not occur. Ionising radiation comes from both natural and man-made sources. Worldwide, medical exposure accounts for 98% of the dose received from man-made sources. In France, the average dose per person received from diagnostic radiological examinations increased by more than 50% between 2002 and 2007. This increase was due to more frequent use of computed tomography (CT) and diagnostic nuclear medicine procedures. The internationally defined individual dose limits for the general population do not apply to the medical uses of ionising radiation, but medical exposure must comply with the principles of radiation protection: the examination must be justified and the dose optimised. In France, shortcomings are observed in the application of these principles. In 2012, the French Nuclear Safety Authority (ASN) received 345 reports of "significant radiation protection incidents" affecting patients: 75% involving external beam radiotherapy, 15% involving nuclear medicine, 6% involving CT scans, and 4% involving radiology. In 2011, reference levels were established for the doses received by children during CT imaging and nuclear medicine procedures. When deciding whether to order a diagnostic procedure using ionising radiation, the harm-benefit balance of both the procedure and the chosen technique must be taken into account. When two procedures have the same performance, the technique that exposes the patient to the lowest dose of radiation should be chosen.

  9. Cataract after repeated daily in vivo exposure to ultraviolet radiation.

    Science.gov (United States)

    Galichanin, Konstantin; Löfgren, Stefan; Söderberg, Per

    2014-12-01

    Epidemiological data indicate a correlation between lifelong exposure to ultraviolet radiation and cortical cataract. However, there is no quantitative experimental data on the effect of daily repeated in vivo exposures of the eye to UVR. Therefore, this experiment was designed to verify whether the dose additivity for UVR exposures holds through periods of time up to 30 d. Eighty rats were conditioned to a rat restrainer 5 d prior to exposure. All animals were divided into four exposure period groups of 1, 3, 10, and 30 d of exposure to UVR. Each exposure period group of 20 animals was randomly divided into five cumulated UVR dose subgroups. Eighteen-wk-old non-anesthetized albino Sprague-Dawley rats were exposed daily to UVR-300 nm for 15 min. One week after the last exposure, animals were sacrificed. The lenses were extracted for macroscopic imaging of dark-field anatomy, and degree of cataract was quantified by measurement of the intensity of forward lens light scattering. Maximum tolerable dose (MTD(2.3:16)), a statistically defined standard for sensitivity for the threshold for UVR cataract, was estimated for each exposure period. Exposed lenses developed cataract with varying appearance on the anterior surface. Single low doses of UVR accumulated to cause cataract during periods up to 30 d. MTD(2.3:16) for 1, 3, 10, and 30 d of repeated exposures was estimated to 4.70, 4.74, 4.80, and 6.00 kJ m(-2), respectively. In conclusion, the lens sensitivity to UVR-B for 18-wk-old Sprague-Dawley rats decreases with the increasing number of days being exposed.

  10. Predictive modeling of terrestrial radiation exposure from geologic materials

    Science.gov (United States)

    Haber, Daniel A.

    Aerial gamma ray surveys are an important tool for national security, scientific, and industrial interests in determining locations of both anthropogenic and natural sources of radioactivity. There is a relationship between radioactivity and geology and in the past this relationship has been used to predict geology from an aerial survey. The purpose of this project is to develop a method to predict the radiologic exposure rate of the geologic materials in an area by creating a model using geologic data, images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), geochemical data, and pre-existing low spatial resolution aerial surveys from the National Uranium Resource Evaluation (NURE) Survey. Using these data, geospatial areas, referred to as background radiation units, homogenous in terms of K, U, and Th are defined and the gamma ray exposure rate is predicted. The prediction is compared to data collected via detailed aerial survey by our partner National Security Technologies, LLC (NSTec), allowing for the refinement of the technique. High resolution radiation exposure rate models have been developed for two study areas in Southern Nevada that include the alluvium on the western shore of Lake Mohave, and Government Wash north of Lake Mead; both of these areas are arid with little soil moisture and vegetation. We determined that by using geologic units to define radiation background units of exposed bedrock and ASTER visualizations to subdivide radiation background units of alluvium, regions of homogeneous geochemistry can be defined allowing for the exposure rate to be predicted. Soil and rock samples have been collected at Government Wash and Lake Mohave as well as a third site near Cameron, Arizona. K, U, and Th concentrations of these samples have been determined using inductively coupled mass spectrometry (ICP-MS) and laboratory counting using radiation detection equipment. In addition, many sample locations also have

  11. Establishment of database for radiation exposure and safety assessment

    Energy Technology Data Exchange (ETDEWEB)

    Choi, G. S.; Kim, J. H. [Science Culture Research Institute, Seoul (Korea, Republic of)

    2005-12-15

    The nuclear electric energy in our country plays a major role for the national industrial development as well as for the secure living of the peoples. It is, however, considered as a socially dreadful elements because of the radiation materials exposed into the environment. In effect, the DB is intended to serve for the reference to the epidemical study upon the low-level radiation exposure involving the nuclear facilities, radio-isotope business enterprises, and the related workers at the radiation sites. In connection with the development of nuclear energy, the low-level radiation, associated with the radioisotope materials exposed into our environment out of nuclear facilities, is believed to possibly raise significant hazardous effects toward human persons. Therefor, it is necessary to take a positive counter measures by means of comprehensive quantitative estimates on its possibilities. In consequence, the low-level radiation effects do not bring about the immediate hazard cases, however, appear to possibly pose the lately caused diseases such as cancer cause, life reduction, and creation of mutation, etc. Therefore, it is intended to set up the social security with the secure safety, by conducting an advanced safety study on the low-level radiation.

  12. General Principles of Radiation Protection in Fields of Diagnostic Medical Exposure

    OpenAIRE

    Do, Kyung Hyun

    2016-01-01

    After the rapid development of medical equipment including CT or PET-CT, radiation doses from medical exposure are now the largest source of man-made radiation exposure. General principles of radiation protection from the hazard of ionizing radiation are summarized as three key words; justification, optimization, and dose limit. Because medical exposure of radiation has unique considerations, diagnostic reference level is generally used as a reference value, instead of dose limits. In Korea, ...

  13. Approximating the Probability of Mortality Due to Protracted Radiation Exposures

    Science.gov (United States)

    2016-06-01

    Protracted Radiation Exposures DTRA-TR-16-054 HDTRA1-14-D-0003; 0005 Prepared by: Applied Research Associates, Inc. 801 N. Quincy Street...RIPD) software developed by the Defense Nuclear Agency in the 1990s. The purpose of this paper is to better explain the qualitative and...affected by this small difference in exponent . Operationally, two factors will determine the fallout age-at-entry. The first, obviously, is the time

  14. Novel Human Radiation Exposure Biomarker Panel Applicable for Population Triage

    Energy Technology Data Exchange (ETDEWEB)

    Bazan, Jose G. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Chang, Polly; Balog, Robert; D' Andrea, Annalisa; Shaler, Thomas; Lin, Hua; Lee, Shirley; Harrison, Travis [SRI International, Menlo Park, California (United States); Shura, Lei; Schoen, Lucy; Knox, Susan J. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Cooper, David E., E-mail: david.cooper@sri.com [SRI International, Menlo Park, California (United States)

    2014-11-01

    Purpose: To identify a panel of radiation-responsive plasma proteins that could be used in a point-of-care biologic dosimeter to detect clinically significant levels of ionizing radiation exposure. Methods and Materials: Patients undergoing preparation for hematopoietic cell transplantation using radiation therapy (RT) with either total lymphoid irradiation or fractionated total body irradiation were eligible. Plasma was examined from patients with potentially confounding conditions and from normal individuals. Each plasma sample was analyzed for a panel of 17 proteins before RT was begun and at several time points after RT exposure. Paired and unpaired t tests between the dose and control groups were performed. Conditional inference trees were constructed based on panels of proteins to compare the non-RT group with the RT group. Results: A total of 151 patients (62 RT, 41 infection, 48 trauma) were enrolled on the study, and the plasma from an additional 24 healthy control individuals was analyzed. In comparison with to control individuals, tenascin-C was upregulated and clusterin was downregulated in patients receiving RT. Salivary amylase was strongly radiation responsive, with upregulation in total body irradiation patients and slight downregulation in total lymphoid irradiation patients compared with control individuals. A panel consisting of these 3 proteins accurately distinguished between irradiated patients and healthy control individuals within 3 days after exposure: 97% accuracy, 0.5% false negative rate, 2% false positive rate. The accuracy was diminished when patients with trauma, infection, or both were included (accuracy, 74%-84%; false positive rate, 14%-33%, false negative rate: 8%-40%). Conclusions: A panel of 3 proteins accurately distinguishes unirradiated healthy donors from those exposed to RT (0.8-9.6 Gy) within 3 days of exposure. These findings have significant implications in terms of triaging individuals in the case of nuclear or other

  15. KREAM: Korean Radiation Exposure Assessment Model for Aviation Route Dose

    Science.gov (United States)

    Hwang, J.; Dokgo, K.; Choi, E. J.; Kim, K. C.; Kim, H. P.; Cho, K. S. F.

    2014-12-01

    Since Korean Air has begun to use the polar route from Seoul/ICN airport to New York/JFK airport on August 2006, there are explosive needs for the estimation and prediction against cosmic radiation exposure for Korean aircrew and passengers in South Korea from public. To keep pace with those needs of public, Korean government made the law on safety standards and managements of cosmic radiation for the flight attendants and the pilots in 2013. And we have begun to develop our own Korean Radiation Exposure Assessment Model (KREAM) for aviation route dose since last year funded by Korea Meteorological Administration (KMA). GEANT4 model and NRLMSIS 00 model are used for calculation of the energetic particles' transport in the atmosphere and for obtaining the background atmospheric neutral densities depending on altitude. For prediction the radiation exposure in many routes depending on the various space weather effects, we constructed a database from pre-arranged simulations using all possible combinations of R, S, and G, which are the space weather effect scales provided by the National Oceanic and Atmospheric Administration (NOAA). To get the solar energetic particles' spectrum at the 100 km altitude which we set as a top of the atmospheric layers in the KREAM, we use ACE and GOES satellites' proton flux observations. We compare the results between KREAM and the other cosmic radiation estimation programs such as CARI-6M which is provided by the Federal Aviation Agency (FAA). We also validate KREAM's results by comparison with the measurement from Liulin-6K LET spectrometer onboard Korean commercial flights and Korean Air Force reconnaissance flights.

  16. RADIOFREQUENCY AND MICROWAVE RADIATION HEALTH EFFECTS AND OCCUPATIONAL EXPOSURE

    Directory of Open Access Journals (Sweden)

    Ivana Damnjanović

    2011-12-01

    Full Text Available In the recent years, there have been considerable discussion and concern about the possible hazards of RF/MW radiation. More recently, the growth and development in personal mobile communications have focused attention on the frequencies associated with this technology. A number of studies have examined the health effects of RF/MW electromagnetic fields (EMFs, originating from occupational exposure, hobbies, or residence near the radio or television transmitters. Particularly controversial are the biophysical mechanisms by which these RF fields may affect biological systems. General health effects reviews explore possible carcinogenic, reproductive and neurological effects. Health effects by exposure source have been observed in radar traffic devices, wireless communications with cellular phones, radio transmission, and magnetic resonance imaging (MRI. Several epidemiological surveys have suggested associations with non-specific complaints such as headache, tiredness, sleep disturbance, loss of memory, and dizziness. These findings, which echo reports of illness associated with other types of radiofrequency (RF radiation, relate not only to the use of mobile phones, but also to residence near the mobile phone base stations and other settings involving occupational exposure. The biological effects suggest that some precautions are necessary, and preventive approaches are highly recommended. Further researches are required to give more information about the effects of microwave radiation on our health, especially in occupational setting and professionally exposed workers.

  17. 47 CFR 2.1091 - Radiofrequency radiation exposure evaluation: mobile devices.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Radiofrequency radiation exposure evaluation... Procedures Radiofrequency Radiation Exposure § 2.1091 Radiofrequency radiation exposure evaluation: mobile... stations devices only) and part 90 of this chapter are subject to routine environmental evaluation for...

  18. 47 CFR 2.1093 - Radiofrequency radiation exposure evaluation: portable devices.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Radiofrequency radiation exposure evaluation... Procedures Radiofrequency Radiation Exposure § 2.1093 Radiofrequency radiation exposure evaluation: portable.... These criteria for SAR evaluation are similar to those recommended by the National Council on...

  19. Occupational radiation Exposure at Agreement State-Licensed Materials Facilities, 1997-2010

    Energy Technology Data Exchange (ETDEWEB)

    U.S. Nuclear Regulatory Commission, Office of Nuclear Regulatory Research

    2012-07-07

    The purpose of this report is to examine occupational radiation exposures received under Agreement State licensees. As such, this report reflects the occupational radiation exposure data contained in the Radiation Exposure Information and Reporting System (REIRS) database, for 1997 through 2010, from Agreement State-licensed materials facilities.

  20. Nodular goiter after occupational accidental exposure to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pisarev, M.A. [Radiobiology, National Atomic Energy Commission, Buenos Aires (Argentina); Human Biochemistry, Uninversity of Buenos Aires, School of Medicine, Buenos Aires (Argentina); Schnitman, M. [Center of Endocrinology and Metabolism, French Hospital C.Milstein, Buenos Aires (Argentina)

    2012-07-01

    In the present paper we present the consequences of an accidental occupational radiation exposure at a local hospital in Buenos Aires. Control at a local radiology service showed the lack of correct shielding in the X-ray equipment. The physicians and technicians (14 persons) exposed to radiation during 12 months were examined. The survey shows that: a) In 11 out of 14 radiation-exposed patients nodular goiter developed and an additional patient had diffuse goiter which means a goiter incidence of 85.7%; b) In 5 of the nodular goiter patients an increase in the size or the appearance of new nodules was observed along the follow-up period. No cancer was detected by FNA; c) Hypothyroidism was observed in 3/14 patients, and an additional patient had an abnormal TRH-TSH test, suggesting subclinical hypothyroidism; and d) Increased circulating antithyroid antibodies were found in one of the hypothyroid patients

  1. Elastomeric Seal Performance after Terrestrial Ultraviolet Radiation Exposure

    Science.gov (United States)

    Daniels, Christopher C.; Oravec, Heather A.; Mather, Janice L.; Taylor, Shawn C.; Dunlap, Patrick H.

    2015-01-01

    Ultraviolet radiation was evaluated to determine its negative effects on the performance of elastomeric gas pressure seals. The leak rates of the silicone elastomer S0383-70 O-ring test articles were used to quantify the degradation of the seals after exposure to vacuum-ultraviolet and/or middle-to-near-ultraviolet wavelength radiation. Three groups of seals were exposed in terrestrial facilities to 115-165 nm wavelength radiation, 230-500 nm wavelength radiation, or both spectrums, for an orbital spaceflight equivalent of 125 hours. The leak rates of the silicone elastomer S0383-70 seals were quantified and compared to samples that received no radiation. Each lot contained six samples and statistical t-tests were used to determine the separate and combined influences of exposure to the two wavelength ranges. A comparison of the mean leak rates of samples exposed to 115-165 nm wavelength radiation to the control specimens showed no difference, suggesting that spectrum was not damaging. The 230-500 nm wavelength appeared to be damaging, as the mean leak rates of the specimens exposed to that range of wavelengths, and those exposed to the combined 115-165 nm and 230-500 nm spectrums, were significantly different from the leak rates of the control specimens. Most importantly, the test articles exposed to both wavelength spectrums exhibited mean leak rates two orders of magnitude larger than any other exposed specimens, which suggested that both wavelength spectrums are important when simulating the orbital environment.

  2. Assessment of risks from occupational exposure to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, E. S.

    1979-01-01

    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.

  3. Radiation Exposure in Transjugular Intrahepatic Portosystemic Shunt Creation

    Energy Technology Data Exchange (ETDEWEB)

    Miraglia, Roberto, E-mail: rmiraglia@ismett.edu; Maruzzelli, Luigi, E-mail: lmaruzzelli@ismett.edu; Cortis, Kelvin, E-mail: kelvincortis@ismett.edu [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Radiology Service, Department of Diagnostic and Therapeutic Services (Italy); D’Amico, Mario, E-mail: mdamico@ismett.edu [University of Palermo, Department of Radiology (Italy); Floridia, Gaetano, E-mail: gfloridia@ismett.edu; Gallo, Giuseppe, E-mail: ggallo@ismett.edu; Tafaro, Corrado, E-mail: ctafaro@ismett.edu; Luca, Angelo, E-mail: aluca@ismett.edu [Mediterranean Institute for Transplantation and Advanced Specialized Therapies (ISMETT), Radiology Service, Department of Diagnostic and Therapeutic Services (Italy)

    2016-02-15

    PurposeTransjugular intrahepatic portosystemic shunt (TIPS) creation is considered as being one of the most complex procedures in abdominal interventional radiology. Our aim was twofold: quantification of TIPS-related patient radiation exposure in our center and identification of factors leading to reduced radiation exposure.Materials and methodsThree hundred and forty seven consecutive patients underwent TIPS in our center between 2007 and 2014. Three main procedure categories were identified: Group I (n = 88)—fluoroscopic-guided portal vein targeting, procedure done in an image intensifier-based angiographic system (IIDS); Group II (n = 48)—ultrasound-guided portal vein puncture, procedure done in an IIDS; and Group III (n = 211)—ultrasound-guided portal vein puncture, procedure done in a flat panel detector-based system (FPDS). Radiation exposure (dose-area product [DAP], in Gy cm{sup 2} and fluoroscopy time [FT] in minutes) was retrospectively analyzed.ResultsDAP was significantly higher in Group I (mean ± SD 360 ± 298; median 287; 75th percentile 389 Gy cm{sup 2}) as compared to Group II (217 ± 130; 178; 276 Gy cm{sup 2}; p = 0.002) and Group III (129 ± 117; 70; 150 Gy cm{sup 2}p < 0.001). The difference in DAP between Groups II and III was also significant (p < 0.001). Group I had significantly longer FT (25.78 ± 13.52 min) as compared to Group II (20.45 ± 10.87 min; p = 0.02) and Group III (19.76 ± 13.34; p < 0.001). FT was not significantly different between Groups II and III (p = 0.73).ConclusionsReal-time ultrasound-guided targeting of the portal venous system during TIPS creation results in a significantly lower radiation exposure and reduced FT. Further reduction in radiation exposure can be achieved through the use of modern angiographic units with FPDS.

  4. 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.

  5. The relationship between occupational radiation exposure and thyroid nodules

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2012-01-01

    Full Text Available Background: Considering that thyroid nodules and thyroid cancer occur more frequently in people chronically exposed to radiation, the aim of this study was to evaluate the prevalence of thyroid nodules in a population occupationally exposed to radiation in hospitals of Isfahan, Iran. Materials and Methods: In this case-control study, the prevalence of thyroid nodules in staff members occupationally exposed to radiation was determined by ultrasonography. The results were compared with the results of another study among the adult population of Isfahan which selected by cluster random sampling method. The 2 studied groups were matched according to sex and age. Results: The case and control groups included 124 and 471 persons, respectively. The prevalence of thyroid nodules in the case and control groups was 22.6% and 24.6%, respectively (p > 0.05. Although thyroid nodules were significantly more prevalent in females in the control group, no such difference was observed between females and males of the case group (p > 0.05. The number of thyroid nodules (single or multiple and calcification were not different between the two groups (p > 0.05. In addition, hypoechogenicity of thyroid nodules was not different between the two groups for (p > 0.05. Conclusion: In our study, there was not any correlation between chronic occupational exposure to low dose of radiation and the risk of developing thyroid nodules. Further studies with larger sample sizes, at different doses of radiation, and considering iodine status and thyroid function are thus required.

  6. How to Reduce Radiation Exposure to Physicians Performing Fluoroscopy Procedures?

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwang Pyo [Dept. of Nuclear Engineering, Kyung Hee University, Seoul (Korea, Republic of)

    2009-04-15

    Fluoroscopy procedures refer to a group of procedures which use real-time moving radiological images of patient internal organs and blood vessels. The procedure can be diagnostic, therapeutic, or both. The fluoroscopy procedures have substantially expanded both in scope and in number. Currently various medical specialties, including radiology, neurology, cardiology, electrophysiology, surgery, orthopedics, urology, gastroenterology etc. perform fluoroscopy procedures One concern of the fluoroscopy procedures is radiation exposure to physicians and thus potential cancer risk. Physicians generally stand close to a patient during a procedure and are exposed radiation scattered from the patient. Physicians perform numbers of procedures during the lifetime and receive cumulative radiation doses. According to a recent systematic review of occupation radiation dose from cardiac fluoroscopy procedures, physician doses varied by 100-1000 times for the same type of procedure. The large variation in the doses suggests that occupational dose can be greatly reduced by considering what factors and how much these factor influence physician doses from fluoroscopy procedures. The present study identifies and discusses various factors that affect radiation dose to physicians performing fluoroscopy procedures.

  7. Evaluation of exposure to ionizing radiation among gamma camera operators

    Directory of Open Access Journals (Sweden)

    Agnieszka Anna Domańska

    2013-08-01

    Full Text Available Background: Protection of nuclear medicine unit employees from hazards of the ionizing radiation is a crucial issue of radiation protection services. We aimed to assess the severity of the occupational radiation exposure of technicians performing scintigraphic examinations at the Nuclear Medicine Department, Central Teaching Hospital of Medical University in Łódź, where thousands of different diagnostic procedures are performed yearly. Materials and Methods: In 2013 the studied diagnostic unit has employed 10 technicians, whose exposure is permanently monitored by individual dosimetry. We analyzed retrospective data of quarterly doses in terms of Hp(10 dose equivalents over the years 2001-2010. Also annual and five-year doses were determined to relate the results to current regulations. Moreover, for a selected period of one year, we collected data on the total activity of radiopharmaceuticals used for diagnostics, to analyze potential relationship with doses recorded in technicians performing the examinations. Results: In a 10-year period under study, the highest annual dose recorded in a technician was 2 mSv, which represented 10% of the annual dose limit of 20 mSv. The highest total dose for a 5-year period was 7.1 mSv, less than 10% of a 5-year dose limit for occupational exposure. Positive linear correlation was observed between total activity of radiopharmaceuticals used for diagnostics in the period of three months and respective quarterly doses received by technicians performing examinations. Conclusions: Doses received by nuclear medicine technicians performing diagnostic procedures in compliance with principles of radiation protection are low, which is confirmed by recognizing the technicians of this unit as B category employees. Med Pr 2013;64(4:503–506

  8. Method for imaging quantum dots during exposure to gamma radiation

    Science.gov (United States)

    Immucci, Andrea N.; Chamson-Reig, Astrid; Yu, Kui; Wilkinson, Diana; Li, Chunsheng; Stodilka, Robert Z.; Carson, Jeffrey J. L.

    2011-03-01

    Quantum dots have been used in a wide variety of biomedical applications. A key advantage of these particles is that their optical properties depend predictably on size, which enables tuning of the emission wavelength. Recently, it was found that CdSe/ZnS quantum dots lose their ability to photoluminescence after exposure to gamma radiation (J. Phys. Chem. C., 113: 2580-2585 (2009). A method for readout of the loss of quantum dot photoluminescence during exposure to radiation could enable a multitude of real-time dosimetry applications. Here, we report on a method to image photoluminescence from quantum dots from a distance and under ambient lighting conditions. The approach was to construct and test a time-gated imaging system that incorporated pulsed illumination. The system was constructed from a pulsed green laser (Nd:YAG, 20 pulses/s, 5 ns pulse duration, ~5 mJ/pulse), a time-gated camera (LaVision Picostar, 2 ns gate width), and optical components to enable coaxial illumination and imaging. Using the system to image samples of equivalent concentration to the previous end-point work, quantum dot photoluminescence was measureable under ambient room lighting at a distance of 25 cm from the sample with a signal to background of 7.5:1. Continuous exposure of samples to pulsed laser produced no measureable loss of photoluminescence over a time period of one hour. With improvements to the light collection optics the range of the system is expected to increase to several metres, which will enable imaging of samples during exposure to a gamma radiation source.

  9. Acute radiation enteritis caused by dose-dependent radiation exposure in dogs: experimental research.

    Science.gov (United States)

    Xu, Wenda; Chen, Jiang; Xu, Liu; Li, Hongyu; Guo, Xiaozhong

    2014-12-01

    Accidental or intended radiation exposure in mass casualty settings presents a serious and on-going threat. The development of mitigating and treating agents requires appropriate animal models. Unfortunately, the majority of research on radiation enteritis in animals has lacked specific assessments and targeted therapy. Our study showed beagle dogs, treated by intensity-modulated radiation therapy (IMRT) for abdominal irradiation, were administered single X-ray doses of 8-30 Gy. The degree of intestinal tract injury for all of the animals after radiation exposure was evaluated with regard to clinical syndrome, endoscopic findings, histological features, and intestinal function. The range of single doses (8 Gy, 10-14 Gy, and 16-30 Gy) represented the degree of injury (mild, moderate, and severe, respectively). Acute radiation enteritis included clinical syndrome with fever, vomiting, diarrhea, hemafecia, and weight loss; typical endoscopic findings included edema, bleeding, mucosal abrasions, and ulcers; and intestinal biopsy results revealed mucosal necrosis, erosion, and loss, inflammatory cell infiltration, hemorrhage, and congestion. Changes in serum diamine oxides (DAOs) and d-xylose represented intestinal barrier function and absorption function, respectively, and correlated with the extent of damage (P enteritis, thus obtaining a relatively objective evaluation of intestinal tract injury based on clinical performance and laboratory examination. The method of assessment of the degree of intestinal tract injury after abdominal irradiation could be beneficial in the development of novel and effective therapeutic strategies for acute radiation enteritis.

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

    Science.gov (United States)

    Kennedy, Ann; Cengel, Keith

    2012-07-01

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

  12. Virtual reality application for simulating and minimizing worker radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Ki Doo [Korea Hydro and Nuclear Power Co., Taejon (Korea, Republic of); Hajek, Brian K. [Ohio State University, columbus (United States); Lee, Yon Sik [Kunsan National University, Kunsan (Korea, Republic of); Shin, Yoo Jin [Kwangwoon University, Seoul (Korea, Republic of)

    2004-07-01

    To plan work and preclude unexpected radiation exposures in a nuclear power plant, a virtual nuclear plant is a good solution. For this, there are prerequisites such as displaying real time radiation exposure data onto an avatar and preventing speed reduction caused by multiple users on the net-based system. The work space is divided into several sections and radiation information is extracted section by section. Based on the simulation algorithm, real time processing is applied to the events and movements of the avatar. Because there are millions of parts in a nuclear power plant, it is almost impossible to model all of them. Several parts of virtual plant have been modeled using 3D internet virtual reality for the model development. Optimum one-click Active-X is applied for the system, which provides easy access to the virtual plant. Connection time on the net is 20-30 sec for initial loading and 3-4 sec for the 2nd and subsequent times.

  13. Saeteilyn kaeyttoe ja muu saeteilytoiminta. Vuosiraportti 1999; Radiation usage and other radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rantanen, E. [ed.

    2000-05-01

    At the end of 1999, there were 1,753 valid safety licenses in Finland for the use of radiation. In addition, there were 2,054 responsible parties for dental x-ray diagnostics. The registry of STUK - Radiation and Nuclear Safety Authority listed 13,687 radiation sources and 278 radionuclide laboratories. The import of radioactive substances amounted to 7 448,000 GBq and export to 18,300 GBq. Short-lived radionuclides produced in Finland amounted to 52,500 GBq. In the year 1999 there were 10,601 workers monitored for radiation exposure at 1,187 work sites. Of these employees, 21% received an annual dose exceeding the recording level. The annual effective dose limit was not exceeded. The total dose recorded in the dose registry (sum of the individual dosemeter readings) was 4.7 Sv in 1999. During the year radon was monitored at 300 companies.

  14. Saeteilyn kaeyttoe ja muu saeteilytoiminta. Vuosiraportti 1999; Radiation usage and other radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Rantanen, E. [ed.

    2000-05-01

    At the end of 1999, there were 1,753 valid safety licenses in Finland for the use of radiation. In addition, there were 2,054 responsible parties for dental x-ray diagnostics. The registry of STUK - Radiation and Nuclear Safety Authority listed 13,687 radiation sources and 278 radionuclide laboratories. The import of radioactive substances amounted to 7 448,000 GBq and export to 18,300 GBq. Short-lived radionuclides produced in Finland amounted to 52,500 GBq. In the year 1999 there were 10,601 workers monitored for radiation exposure at 1,187 work sites. Of these employees, 21% received an annual dose exceeding the recording level. The annual effective dose limit was not exceeded. The total dose recorded in the dose registry (sum of the individual dosemeter readings) was 4.7 Sv in 1999. During the year radon was monitored at 300 companies.

  15. Titanium-Water Thermosyphon Gamma Radiation Exposure and Results

    Science.gov (United States)

    Sanzi, James, L.A; Jaworske, Donald, A.; Goodenow, Debra, A.

    2012-01-01

    Titanium-water thermosyphons are being considered for use in heat rejection systems for fission power systems. Their proximity to the nuclear reactor will result in some gamma irradiation. Noncondensable gas formation from radiation-induced breakdown of water over time may render portions of the thermosyphon condenser inoperable. A series of developmental thermosyphons were operated at nominal operating temperature under accelerated gamma irradiation, with exposures on the same order of magnitude as that expected in 8 years of heat rejection system operation. Temperature data were obtained during exposure at three locations on each thermosyphon: evaporator, condenser, and condenser end cap. Some noncondensable gas was evident; however, thermosyphon performance was not affected because the noncondensable gas was compressed into the fill tube region at the top of the thermosyphon, away from the heat rejecting fin. The trend appeared to be an increasing amount of noncondensable gas formation with increasing gamma irradiation dose. Hydrogen is thought to be the most likely candidate for the noncondensable gas and hydrogen is known to diffuse through grain boundaries. Post-exposure evaluation of one thermosyphon in a vacuum chamber and at temperature revealed that the noncondensable gas diffused out of the thermosyphon over a relatively short period of time. Further research shows a number of experimental and theoretical examples of radiolysis occurring through gamma radiation alone in pure water.

  16. Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station.

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

    2017-02-01

    Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37°C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37°C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space.

  17. Detection of DNA damage by space radiation in human fibroblasts flown on the International Space Station

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; Karouia, Fathi; Wu, Honglu

    2017-02-01

    Although charged particles in space have been detected with radiation detectors on board spacecraft since the discovery of the Van Allen Belts, reports on the effects of direct exposure to space radiation in biological systems have been limited. Measurement of biological effects of space radiation is challenging due to the low dose and low dose rate nature of the radiation environment, and due to the difficulty in distinguishing the radiation effects from microgravity and other space environmental factors. In astronauts, only a few changes, such as increased chromosome aberrations in their lymphocytes and early onset of cataracts, are attributed primarily to their exposure to space radiation. In this study, cultured human fibroblasts were flown on the International Space Station (ISS). Cells were kept at 37 °C in space for 14 days before being fixed for analysis of DNA damage with the γ-H2AX assay. The 3-dimensional γ-H2AX foci were captured with a laser confocal microscope. Quantitative analysis revealed several foci that were larger and displayed a track pattern only in the Day 14 flight samples. To confirm that the foci data from the flight study was actually induced from space radiation exposure, cultured human fibroblasts were exposed to low dose rate γ rays at 37 °C. Cells exposed to chronic γ rays showed similar foci size distribution in comparison to the non-exposed controls. The cells were also exposed to low- and high-LET protons, and high-LET Fe ions on the ground. Our results suggest that in G1 human fibroblasts under the normal culture condition, only a small fraction of large size foci can be attributed to high-LET radiation in space.

  18. In utero exposure to microwave radiation and rat brain development.

    Science.gov (United States)

    Merritt, J H; Hardy, K A; Chamness, A F

    1984-01-01

    Timed-pregnancy rats were exposed in a circular waveguide system starting on day 2 of gestation. The system operated at 2,450 MHz (pulsed waves; 8 microseconds PW; 830 pps). Specific absorption rate (SAR) was maintained at 0.4 W/kg by increasing the input power as the animals grew in size. On day 18 of gestation the dams were removed from the waveguide cages and euthanized; the fetuses were removed and weighed. Fetal brains were excised and weighed, and brain RNA, DNA and protein were determined. Values for measured parameters of the radiated fetuses did not differ significantly from those of sham-exposed fetuses. A regression of brain weight on body weight showed no micrencephalous fetuses in the radiation group when using as a criterion a regression line based on two standard errors of the estimate of the sham-exposed group. In addition, metrics derived from brain DNA (ie, cell number and cell size) showed no significant differences when radiation was compared to sham exposure. We conclude that 2,450-MHz microwave radiation, at an SAR of 0.4 W/kg, did not produce significant alterations in brain organogenesis.

  19. Is Exposure to Low Radiation Levels Good For You?

    Science.gov (United States)

    Dimitroyannis, Dimitri

    1996-05-01

    Little is known about the biological effects of very low levels of ionizing radiation. We propose an experiment to compare cell response to such low radiation levels, using fast replicating yeast cells. Saccharomyces Cerevisae (SC), a type of yeast, is an eukariotic unicellular microorganism with a mean cell generation time of 90 min. Its genetic organization is similar to that of superior organisms, but at the same time is very easy to handle, with special reference to its genetic analysis. Certain CS strains are widely employed for mutagenesis studies. We propose to expose simultaneously three indentical CS cultures for a period of up to a few weeks (100s of cell generations): to natural backgroung (NB) ionizing radiation (at a ground level lab), to sub-NB level (underground) and to supra-NB level (at a high altitude). At the end of the exposure we will chemically challenge the cultured cells with methyl-methane-sulphonate (MMS), a standard chemical mutagen. Mitotic recombination frequency in the MMS exposed cultures is an index of early DNA damage induction at high survival levels (ie at very low radiation levels). This experiment can be handsomely and inexpensively accomodated in one of the existing underground laboratories.

  20. Radiation exposure inside reinforced concrete buildings at Nagasaki

    Energy Technology Data Exchange (ETDEWEB)

    Rhoades, W.A.; Childs, R.L.; Ingersoll, D.T.

    1989-05-01

    The biological effects on the residents of Hiroshima and Nagasaki due to initial-irradiation exposure during the nuclear attacks of World War II was recognized immediately as an important source of information. After the war, an extensive effort gathered data concerning the locations of individuals at the time of the attack and their subsequent medical histories. The data from personnel located in reinforced concrete buildings are particularly significant, since large groups of occupants received radiation injury without complications due to blast and thermal effects. In order to correlate the radiation dose with physiological effects, the dose to each individual must be calculated. Enough information about the construction of the buildings was available after the war to allow a radiation transport model to be constructed, but the accurate calculation of penetration into such large, thick-walled three dimensional structures was beyond the scope of computing technology until recently. Now, the availability of Cray vector computers and the development of a specially-constructed discrete ordinates transport code, TORT, have combined to allow the successful completion of such a study. This document describes the radiation transport calculations and tabulates the resulting doses by source component and individual case location. An extensive uncertainty analysis is also included. These data are to be used in another study as input to a formal statistical analysis, resulting in a new value for the LD50 dose, i.e., the dose at which the mortality risk is 50%. 55 refs., 67 figs., 70 tabs.

  1. [Exposure to noise, vibration and radiation in Cracow].

    Science.gov (United States)

    Jarosz, A; Zołdak, M

    1990-01-01

    The problems are discussed connected with exposure to noise, vibration and ionizing radiation. In Cracow traffic and industrial noise is particularly troublesome. The greatest intensity of traffic noise is in the old part of the city and noise level caused by city transport is from 65 to 85 dB/A. Among the industrial sources of noise the highest intensity is in the Lenin Steel Plant, Leg Electrothermal Plant, and Solway Soda Works. Vibration and ionizing radiation resulting from the industrial activities are a considerable risk for human health in the Cracow area. The building materials in construction (including apartment houses) have sometimes a high radioactivity, e.g. dust-slag hollow bricks. The need is stressed for solving, if possible, the problem of noise, especially traffic noise, which is connected with considerable financial costs; the question of using materials of high radioactivity for building purposes should be also resolved.

  2. 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.

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

    Science.gov (United States)

    Hendry, Jolyon H; Simon, Steven L; Wojcik, Andrzej; Sohrabi, Mehdi; Burkart, Werner; Cardis, Elisabeth; Laurier, Dominique; Tirmarche, Margot; Hayata, Isamu

    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 (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.

  4. Development of a predictive code for aircrew radiation exposure.

    Science.gov (United States)

    McCall, M J; Lemay, F; Bean, M R; Lewis, B J; Bennett, L G I

    2009-10-01

    Using the empirical data measured by the Royal Military College with a tissue equivalent proportional counter, a model was derived to allow for the interpolation of the dose rate for any global position, altitude and date. Through integration of the dose-rate function over a great circle flight path or between various waypoints, a Predictive Code for Aircrew Radiation Exposure (PCAire) was further developed to provide an estimate of the total dose equivalent on any route worldwide at any period in the solar cycle.

  5. Expression of genes involved in mouse lung cell differentiation/regulation after acute exposure to photons and protons with or without low-dose preirradiation.

    Science.gov (United States)

    Tian, Jian; Zhao, WeiLing; Tian, Sisi; Slater, James M; Deng, Zhiyong; Gridley, Daila S

    2011-11-01

    The goal of this study was to compare the effects of acute 2 Gy irradiation with photons (0.8 Gy/min) or protons (0.9 Gy/min), both with and without pre-exposure to low-dose/low-dose-rate γ rays (0.01 Gy at 0.03 cGy/h), on 84 genes involved in stem cell differentiation or regulation in mouse lungs on days 21 and 56. Genes with a ≥1.5-fold difference in expression and P photons in modulating the genes. More genes were affected by protons than by photons (22 compared to 2 and 6 compared to 2 on day 21 and day 56, respectively) compared to 0 Gy. Preirradiation with low-dose-rate γ rays enhanced the acute photon-induced gene modulation on day 21 (11 compared to 2), and all 11 genes were significantly downregulated on day 56. On day 21, seven genes (aldh2, bmp2, cdc2a, col1a1, dll1, foxa2 and notch1) were upregulated in response to most of the radiation regimens. Immunoreactivity of Clara cell secretory protein was enhanced by all radiation regimens. The number of alveolar type 2 cells positive for prosurfactant protein C in irradiated groups was higher on day 56 (12.4-14.6 cells/100) than on day 21 (8.5-11.2 cells/100) (P photons and protons induced different gene expression profiles in the lungs and that pre-exposure to low-dose-rate γ rays sometimes had modulatory effects. In addition, proteins associated with lung-specific stem cells/progenitors were highly sensitive to radiation.

  6. The PI3K/Akt/mTOR pathway is implicated in the premature senescence of primary human endothelial cells exposed to chronic radiation.

    Science.gov (United States)

    Yentrapalli, Ramesh; Azimzadeh, Omid; Sriharshan, Arundhathi; Malinowsky, Katharina; Merl, Juliane; Wojcik, Andrzej; Harms-Ringdahl, Mats; Atkinson, Michael J; Becker, Karl-Friedrich; Haghdoost, Siamak; Tapio, Soile

    2013-01-01

    The etiology of radiation-induced cardiovascular disease (CVD) after chronic exposure to low doses of ionizing radiation is only marginally understood. We have previously shown that a chronic low-dose rate exposure (4.1 mGy/h) causes human umbilical vein endothelial cells (HUVECs) to prematurely senesce. We now show that a dose rate of 2.4 mGy/h is also able to trigger premature senescence in HUVECs, primarily indicated by a loss of growth potential and the appearance of the senescence-associated markers ß-galactosidase (SA-ß-gal) and p21. In contrast, a lower dose rate of 1.4 mGy/h was not sufficient to inhibit cellular growth or increase SA-ß-gal-staining despite an increased expression of p21. We used reverse phase protein arrays and triplex Isotope Coded Protein Labeling with LC-ESI-MS/MS to study the proteomic changes associated with chronic radiation-induced senescence. Both technologies identified inactivation of the PI3K/Akt/mTOR pathway accompanying premature senescence. In addition, expression of proteins involved in cytoskeletal structure and EIF2 signaling was reduced. Age-related diseases such as CVD have been previously associated with increased endothelial cell senescence. We postulate that a similar endothelial aging may contribute to the increased rate of CVD seen in populations chronically exposed to low-dose-rate radiation.

  7. The PI3K/Akt/mTOR pathway is implicated in the premature senescence of primary human endothelial cells exposed to chronic radiation.

    Directory of Open Access Journals (Sweden)

    Ramesh Yentrapalli

    Full Text Available The etiology of radiation-induced cardiovascular disease (CVD after chronic exposure to low doses of ionizing radiation is only marginally understood. We have previously shown that a chronic low-dose rate exposure (4.1 mGy/h causes human umbilical vein endothelial cells (HUVECs to prematurely senesce. We now show that a dose rate of 2.4 mGy/h is also able to trigger premature senescence in HUVECs, primarily indicated by a loss of growth potential and the appearance of the senescence-associated markers ß-galactosidase (SA-ß-gal and p21. In contrast, a lower dose rate of 1.4 mGy/h was not sufficient to inhibit cellular growth or increase SA-ß-gal-staining despite an increased expression of p21. We used reverse phase protein arrays and triplex Isotope Coded Protein Labeling with LC-ESI-MS/MS to study the proteomic changes associated with chronic radiation-induced senescence. Both technologies identified inactivation of the PI3K/Akt/mTOR pathway accompanying premature senescence. In addition, expression of proteins involved in cytoskeletal structure and EIF2 signaling was reduced. Age-related diseases such as CVD have been previously associated with increased endothelial cell senescence. We postulate that a similar endothelial aging may contribute to the increased rate of CVD seen in populations chronically exposed to low-dose-rate radiation.

  8. Radiation exposure due to agricultural uses of phosphate fertilizers

    Energy Technology Data Exchange (ETDEWEB)

    Khater, Ashraf E.M. [National Center for Nuclear Safety and Radiation Control, Atomic Energy Authority, Cairo (Egypt); Physics Department, College of Sciences, King Saud University, P.O. Box 2455, Riyadh 1145 (Saudi Arabia)], E-mail: khater_ashraf@yahoo.com; AL-Sewaidan, H.A. [Physics Department, College of Sciences, King Saud University, P.O. Box 2455, Riyadh 1145 (Saudi Arabia)

    2008-09-15

    Radiological impacts of phosphate rocks mining and manufacture could be significant due to the elevated radioactivity contents of the naturally occurring radioactive materials (NORM), such as {sup 238}U series, {sup 232}Th series and {sup 40}K, in some phosphate deposits. Over the last decades, the land reclamation and agriculture activities in Saudi Arabia and other countries have been widely expanded. Therefore, the usage of chemical fertilizers is increased. Selected phosphate fertilizers samples were collected and the specific activities of NORM were measured using a gamma ray spectrometer based on a hyper pure germanium detector and alpha spectrometer based on surface barrier detector. The obtained results show remarkable wide variations in the radioactivity contents of the different phosphate fertilizer samples. The mean (ranges) of specific activities for {sup 226}Ra, {sup 210}Po, {sup 232}Th and {sup 40}K, and radium equivalent activity are 75 (3-283), 25 (0.5-110), 23 (2-74), 2818 (9-6501) Bq/kg and 283 (7-589) Bq/kg, respectively. Based on dose calculations, the increment of the public radiation exposure due to the regular agricultural usage of phosphate fertilizers is negligible. Its average value 1 m above the ground is about 0.12 nGy/h where the world average value due to the NORM in soil is 51 nGy/h. Direct radiation exposures of the farmers due to phosphate fertilizers application was not considered in our study.

  9. Biological effects of low level exposures to chemicals and radiation

    Energy Technology Data Exchange (ETDEWEB)

    Calabrese, E.J. (ed.)

    1992-01-01

    In May 1990 a group of scientists representing several federal agencies, the International Society of Regulatory Toxicology and Pharmacology, the private sector, and academia met to develop a strategy to encourage the study of the biological effects of low level exposures (BELLE) to chemical agents and radioactivity. A workshop was held in 1991 with seven invited speakers focusing on the toxicological implications of biological adaptations. The selection of topics and speakers was designed to consider critically the concept of hormesis, not only in a broad, conceptual manner, but also at the molecular and biochemical levels. These presentations offered a complementary perspective on the diverse range of molecular mechanisms that can become activated at low levels of toxicant exposure. In addition to chemical toxicology research, an overview of current research on Effects of low-dose radiation on the immune response' was presented as well as Cellular adaptation as an important response during chemical carcinogenesis'. The final presentation was devoted to biostatistical considerations when designing studies that address issues associated with the biological responses to low doses of chemicals and radiation, as well as issues in interpretation of the findings from such studies.

  10. Prenatal exposure to ionizing radiation and subsequent development of seizures

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, K.; Yoshimaru, H.; Otake, M.; Annegers, J.F.; Schull, W.J. (Radiation Effects Research Foundation, Hiroshima (Japan))

    1990-01-01

    Seizures are a frequent sequela of impaired brain development and can be expected to affect more children with radiation-related brain damage than children without such damage. This report deals with the incidence and type of seizures among survivors prenatally exposed to the atomic bombing of Hiroshima and Nagasaki, and their association with specific stages of prenatal development at the time of irradiation. Fetal radiation dose was assumed to be equal to the dose to the maternal uterus. Seizures here include all references in the clinical record to seizure, epilepsy, or convulsion. Histories of seizures were obtained at biennial routine clinical examinations starting at about the age of 2 years. These clinical records were used to classify seizures as febrile or unprovoked (without precipitating cause). No seizures were ascertained among subjects exposed 0-7 weeks after fertilization at doses higher than 0.10 Gy. The incidence of seizures was highest with irradiation at the eighth through the 15th week after fertilization among subjects with doses exceeding 0.10 Gy and was linearly related to the level of fetal exposure. This obtains for all seizures without regard to the presence of fever or precipitating causes, and for unprovoked seizures. When the 22 cases of severe mental retardation were excluded, the increase in seizures was only suggestively significant and only for unprovoked seizures. After exposure at later stages of development, there was no increase in recorded seizures.

  11. Effects in Plant Populations Resulting from Chronic Radiation Exposure

    Energy Technology Data Exchange (ETDEWEB)

    Geras' kin, Stanislav A.; Volkova, Polina Yu.; Vasiliyev, Denis V.; Dikareva, Nina S.; Oudalova, Alla A. [Russian Institute of Agricultural Radiology and Agroecology, 249032, Obninsk (Russian Federation)

    2014-07-01

    environment activates genetic mechanisms, changing a population's resistance to exposure. However, there are ecological situations in which enhanced resistance has not evolved or has not persisted. Consequently, there are good theoretical and practical reasons for more attention being paid to the mechanisms by which populations becomes more radioresistant and to those situations where radio-adaptation appears not to be taking place. Since radio-adaptation plays an important role in response of populations on radiation exposure, this process needs to be incorporated into management programmes. To this very day, the effects of chronic exposure on living organisms and populations remain poorly explored, and represent a much needed field of research. In spite of the long history of the research, we are still far from complete understanding underlying processes in exposed populations. Neglecting field-collected data in favour of simplified short-term experiments that tend to overestimate adverse effects will obviously have detrimental effect for understanding, predicting, and mitigating consequences of the radiation impact on the environment. Much more is to be elucidated in our understanding before we will be able to give an objective and comprehensive assessment of the biological consequences of chronic, low-level radiation exposures to natural plant and animal populations. (authors)

  12. Radiation exposures for DOE contractor employees-1988. Twenty-first annual report

    Energy Technology Data Exchange (ETDEWEB)

    Merwin, S. E. [Pacific Northwest Lab., Richland, WA (United States); Millet, W. H. [Pacific Northwest Lab., Richland, WA (United States); Idaho National Engineering Lab., Idaho Falls, ID (United States); Traub, R. J. [Pacific Northwest Lab., Richland, WA (United States)

    1990-12-01

    This report is one of a series of annual reports provided by the U.S. Department of Energy (DOE) summarizing occupational radiation exposures received by DOE and DOE contractor employees. These reports provide an overview of radiation exposures received each year and identify trends in exposures being experienced over the years.

  13. Radiation Exposures for DOE and DOE Contractor Employees - 1989. Twenty-second annual report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M. H. [Pacific Northwest Lab., Richland, WA (United States); Eschbach, P. A. [Pacific Northwest Lab., Richland, WA (United States); Harty, R. [Pacific Northwest Lab., Richland, WA (United States); Millet, W. H. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Scholes, V. A. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1992-12-01

    This report is one of a series of annual reports provided by the U.S. Department of Energy (DOE) summarizing occupational radiation exposures received by DOE and DOE contractor employees. These reports provide an overview of radiation exposures received each year and identify trends in exposures being experienced over the years.

  14. Late health effects of chronic radiation exposure of bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Yarmoshenko, Ilia V.; Malinovsky, Georgy P.; Konshina, Lidia G.; Zhukovsky, Michael V. [Institute of Industrial Ecology UB RAS, 620219, 20, Sophy Kovalevskoy St., Ekaterinburg (Russian Federation); Tuzankina, Irina A. [Institute of Immunology and Physiology UB RAS, 620049, 106, Pervomayskaya St., Ekaterinburg (Russian Federation)

    2014-07-01

    Accidental explosion of waste storage tank at former soviet plutonium production plant 'Mayak' in 1957 resulted in emission of considerable amount of radioactive substances to the atmosphere. Atmospheric transfer and fallout caused contamination of the environment by Sr-90 and short-lived radionuclides (East-Ural Radioactive Trace, EURT). Due to consumption of contaminated food and milk some internal organs were affected to relatively high radiation exposure. Archive data of causes of deaths of rural population of EURT northern part for period 1957-2000 were used to create the Register on causes of deaths. Register records related to the settlements where initial surface contamination by Sr-90 was above and below 3.7 kBq/m2 were included to exposed (4 844 records) and unexposed (6 158 records) group respectively. Basing on the Register the analysis of cancer and non-cancer health effects of radiation exposure was conducted. By estimating proportionate mortality ratios statistically significant excess mortality due to the groups of causes of death as follow was observed in exposed population: stomach, liver and cervix cancers; group consisted only of stomach cancer; non-cancer deceases of infectious etiology. Non-significant but remarkably high risk was observed for the following groups of causes of death: bone cancer; leukemia; liver cancer; cervix cancer. Insignificant, virtually zero risk was found for: non-gastrointestinal solid cancers; colon and lung cancers; non-infectious non-cancer deceases. At the same time, considerable radiation doses were absorbed in bone (mean bone surface dose about 0.1 Gy) and colon (mean dose about 0.07 Gy). Doses absorbed in other organs and tissues were negligible and amounted less than 0.01 Gy for most tissues. It can be seen that some disagreement between observed effects and absorbed doses is revealed. Most remarkable is the high excess risks of stomach, liver and cervix cancers as well as non-cancer deceases of

  15. Mitigation of Lung Injury after Accidental Exposure to Radiation

    Science.gov (United States)

    Mahmood, J.; Jelveh, S.; Calveley, V.; Zaidi, A.; Doctrow, S. R.; Hill, R. P.

    2011-01-01

    There is a serious need to develop effective mitigators against accidental radiation exposures. In radiation accidents, many people may receive nonuniform whole-body or partial-body irradiation. The lung is one of the more radiosensitive organs, demonstrating pneumonitis and fibrosis that are believed to develop at least partially because of radiation-induced chronic inflammation. Here we addressed the crucial questions of how damage to the lung can be mitigated and whether the response is affected by irradiation to the rest of the body. We examined the widely used dietary supplement genistein given at two dietary levels (750 or 3750 mg/kg) to Fischer rats irradiated with 12 Gy to the lung or 8 Gy to the lung + 4 Gy to the whole body excluding the head and tail (whole torso). We found that genistein had promising mitigating effects on oxidative damage, pneumonitis and fibrosis even at late times (36 weeks) when drug treatment was initiated 1 week after irradiation and stopped at 28 weeks postirradiation. The higher dose of genistein showed no greater beneficial effect. Combined lung and whole-torso irradiation caused more lung-related severe morbidity resulting in euthanasia of the animals than lung irradiation alone. PMID:22013884

  16. Blue Light and Ultraviolet Radiation Exposure from Infant Phototherapy Equipment.

    Science.gov (United States)

    Pinto, Iole; Bogi, Andrea; Picciolo, Francesco; Stacchini, Nicola; Buonocore, Giuseppe; Bellieni, Carlo V

    2015-01-01

    Phototherapy is the use of light for reducing the concentration of bilirubin in the body of infants. Although it has become a mainstay since its introduction in 1958, a better understanding of the efficacy and safety of phototherapy applications seems to be necessary for improved clinical practices and outcomes. This study was initiated to evaluate workers' exposure to Optical Radiation from different types of phototherapy devices in clinical use in Italy. During infant phototherapy the staff monitors babies periodically for around 10 min every hour, and fixation of the phototherapy beam light frequently occurs: almost all operators work within 30 cm of the phototherapy source during monitoring procedures, with most of them commonly working at ≤25 cm from the direct or reflected radiation beam. The results of this study suggest that there is a great variability in the spectral emission of equipments investigated, depending on the types of lamps used and some phototherapy equipment exposes operators to blue light photochemical retinal hazard. Some of the equipment investigated presents relevant spectral emission also in the UVA region. Taking into account that the exposure to UV in childhood has been established as an important contributing factor for melanoma risk in adults and considering the high susceptibility to UV-induced skin damage of the newborn, related to his pigmentary traits, the UV exposure of the infant during phototherapy should be "as low as reasonably achievable," considering that it is unnecessary to the therapy. It is recommended that special safety training be provided for the affected employees: in particular, protective eyewear can be necessary during newborn assistance activities carried out in proximity of some sources. The engineering design of phototherapy equipment can be optimized. Specific requirements for photobiological safety of lamps used in the phototherapy equipment should be defined in the safety product standard for such

  17. Report on the actual conditions of the radiation exposed residents near the former Semipalatinsk nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Kawano, Noriyuki; Taooka, Yasuyuki; Hiraoka, Takashi; Hoshi, Masaharu [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology; Matsuo, Masatsugu [Hiroshima Univ. (Japan). Inst. of Peace Science; Apsalikov Kazbek Negmatovich [Research Inst. for Radiation Medicine and Ecology, Semipalatinsk (Kazakstan); Zhumadilov Zhaxybay Shaimardanovich [Semipalatinsk State Medical Academy (Kazakstan)

    2003-03-01

    This report describes results of the investigation conducted in July 2002 on the health and exposure of the residents in the title of the Kazakhstan Republic, involving the summary of the investigation; hearing of the residents' health states and philological considerations; verbal evidences on the exposure around the Semipalatinsk nuclear test site and their analysis; impressions on the above hearing results; significance of the hearing results in relation to those in ''Hiroshima and Nagasaki''; perspective; and appendix materials (composing 1/2 volume of the report) on the investigation schedule and participants, questionnaire in Japanese and Russian, their actual answering examples in Russian and Kazakhstan languages, pictures drawn in the answering, and appeared newspaper articles related to the present investigation. The exposure in Semipalatinsk is the low dose rate one occurring in the range of several weeks to months, differing from that in Hiroshima and Nagasaki (immediate exposure). Therefore, the present investigation that has been being done for 8 years, can give a novel knowledge on the effects of the low dose rate radiation on humans. (N.I.)

  18. Patient radiation exposure dose evaluation of whole spine scanography due to exposure direction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Su; Seo, Deok Nam [Dept. of Bio-convergence Engineering, Graduate School of Korea University, Seoul (Korea, Republic of); Kwon, Soon Mu [Dept. of Radiologic Technology, Daegu Health College, Daegu (Korea, Republic of); Kim, Jung Min [Dept. of Radiological Science, Korea University, Seoul (Korea, Republic of)

    2015-04-15

    Whole spine scanography (WSS) is a radiological examination that exposes the whole body of the individual being examined to x-ray radiation. WSS is often repeated during the treatment period, which results in a much greater radiation exposure than that in routine x-ray examinations. The aims of the current study were to evaluate the patient dose of WSS using computer simulation, image magnification and angulation of phantom image using different patient position. We evaluated the effective dose(ED) of 23 consecutive patients (M : F = 13:10) who underwent WSS, based on the automatic image pasting method for multiple exposure digital radiography. The Anterior-Posterior position(AP) and Posterior-Anterior position( PA) projection EDs were evaluated based on the PC based Monte Carlo simulation. We measured spine transverse process distance and angulation using DICOM measurement. For all patient, the average ED was 0.069 mSv for AP position and 0.0361 mSv for PA position. AP position calculated double exposure then PA position. For male patient, the average ED was 0.089 mSv(AP) and 0.050 mSv(PA). For female patient, the average ED was 0.0431 mSv(AP) and 0.026 mSv(PA). The transverse process of PA spine image measured 5% higher than AP but angulation of transverse process was no significant differences. In clinical practice, just by change the patient position was conformed to reduce the ED of patient. Therefore we need to redefine of protocol for digital radiography such as WSS, whole spine scanography, effective dose, patient exposure dose, exposure direction, protocol optimization.

  19. Radiation exposure to the physician in interventional pain management.

    Science.gov (United States)

    Manchikanti, Laxmaiah; Cash, Kim A; Moss, Tammy L; Pampati, Vidyasagar

    2002-10-01

    Fluoroscopy is an integral part of the practice of interventional pain management in present day modern medical practices. The major purpose of fluoroscopy in interventional pain management is correct needle placement to ensure target specificity and accurate delivery of the injectate. Fluoroscopy has become mandatory for multiple procedures based either on the definition of the procedure or the requirement of third parties. The most commonly used fluoroscopy in interventional pain management is with C-arm fluoroscopes with image intensification. Fluoroscopy is associated with risk for patients, clinicians, and the personnel in the operating room unless it is managed with appropriate understanding, skill, and vigilance. A total of 1,000 consecutive patients undergoing interventional procedures with chronic pain performed by one physician were studied. Two fluoroscopy units were utilized and operated by two certified radiological technologists. The procedures performed included caudal and interlaminar epidural injections, facet joint nerve blocks, percutaneous adhesiolysis, intercostal nerve blocks, sympathetic blocks, transforaminal epidural injections, along with other procedures. Results showed that a total of 1,000 patients underwent 1,729 procedures with average radiation exposure of 13.2 +/- 0.33 seconds per patient and 7.7 +/- 0.21 seconds per procedure. Dosimetry measurements showed total exposure of 1,345 mREM outside the apron and 0 mREM inside the apron during this period. The average exposure outside the apron was 1.345 mREM per patient and 0.778 mREM per procedure outside the apron and 0 mREM inside the apron. The levels of exposure are significantly below the annual limits recommended. It is concluded that it is feasible to perform all procedures under fluoroscopy in the described setting safely and effectively in interventional pain management.

  20. Radiation exposures for DOE and DOE contractor employees - 1991. Twenty-fourth annual report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, M.H.; Hui, T.E. [Pacific Northwest Lab., Richland, WA (United States); Millet, W.H.; Scholes, V.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-11-01

    This is the 24th annual radiation exposure report published by US DOE and its predecessor agencies. This report summarizes the radiation exposures received by both employees and visitors at DOE and COE contractor facilities during 1991. Trends in radiations exposures are evaluated. The significance of the doses is addressed by comparing them to the DOE limits and by correlating the doses to health risks based on risk estimates from expert groups.

  1. A comparative analysis of exposure doses between the radiation workers in dental and general hospital

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Nam Hee; Chung, Woon Kwan; Dong, Kyung Rae; Ju, Yong Jin; Song, Ha Jin [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of); Choi, Eun Jin [Dept. of Public Health and Medicine, Dongshin University, Naju (Korea, Republic of)

    2015-02-15

    Research and investigation is required for the exposure dose of radiation workers to work in the dental hospital as increasing interest in exposure dose of the dental hospital recently accordingly, study aim to minimize radiation exposure by making a follow-up study of individual exposure doses of radiation workers, analyzing the status on individual radiation exposure management, prediction the radiation disability risk levels by radiation, and alerting the workers to the danger of radiation exposure. Especially given the changes in the dental hospital radiation safety awareness conducted the study in order to minimize radiation exposure. This study performed analyses by a comparison between general and dental hospital, comparing each occupation, with the 116,220 exposure dose data by quarter and year of 5,811 subjects at general and dental hospital across South Korea from January 1, 2008 through December 31, 2012. The following are the results obtained by analyzing average values year and quarter. In term of hospital, average doses were significantly higher in general hospitals than detal ones. In terms of job, average doses were higher in radiological technologists the other workers. Especially, they showed statistically significant differences between radiological technologists than dentists. The above-mentioned results indicate that radiation workers were exposed to radiation for the past 5 years to the extent not exceeding the dose limit (maximum 50 mSv y{sup -1}). The limitation of this study is that radiation workers before 2008 were excluded from the study. Objective evaluation standards did not apply to the work circumstance or condition of each hospital. Therefore, it is deemed necessary to work out analysis criteria that will be used as objective evaluation standard. It will be necessary to study radiation exposure in more precise ways on the basis of objective analysis standard in the future. Should try to minimize the radiation individual dose of

  2. Short-duration exposure to 2.45 GHz microwave radiation induces ...

    African Journals Online (AJOL)

    OBEMBE

    duration of exposure and C is the specific heat capacity of the tissue with the value of C taken ..... long-term exposure to GSM-900 mobile phone radiation. Bioelectromagnetics ... transcription, translation, calcium and energy charge in tomato.

  3. Ionizing radiation exposure in interventional cardiology: current radiation protection practice of invasive cardiology operators in Lithuania.

    Science.gov (United States)

    Valuckiene, Zivile; Jurenas, Martynas; Cibulskaite, Inga

    2016-09-01

    Ionizing radiation management is among the most important safety issues in interventional cardiology. Multiple radiation protection measures allow the minimization of x-ray exposure during interventional procedures. Our purpose was to assess the utilization and effectiveness of radiation protection and optimization techniques among interventional cardiologists in Lithuania. Interventional cardiologists of five cardiac centres were interviewed by anonymized questionnaire, addressing personal use of protective garments, shielding, table/detector positioning, frame rate (FR), resolution, field of view adjustment and collimation. Effective patient doses were compared between operators who work with and without x-ray optimization. Thirty one (68.9%) out of 45 Lithuanian interventional cardiologists participated in the survey. Protective aprons were universally used, but not the thyroid collars; 35.5% (n  =  11) operators use protective eyewear and 12.9% (n  =  4) wear radio-protective caps; 83.9% (n  =  26) use overhanging shields, 58.1% (n  =  18)-portable barriers; 12.9% (n  =  4)-abdominal patient's shielding; 35.5% (n  =  11) work at a high table position; 87.1% (n  =  27) keep an image intensifier/receiver close to the patient; 58.1% (n  =  18) reduce the fluoroscopy FR; 6.5% (n  =  2) reduce the fluoro image detail resolution; 83.9% (n  =  26) use a 'store fluoro' option; 41.9% (N  =  13) reduce magnification for catheter transit; 51.6% (n  =  16) limit image magnification; and 35.5% (n  =  11) use image collimation. Median effective patient doses were significantly lower with x-ray optimization techniques in both diagnostic and therapeutic interventions. Many of the ionizing radiation exposure reduction tools and techniques are underused by a considerable proportion of interventional cardiology operators. The application of basic radiation protection tools and

  4. Review of photokeratitis: Corneal response to ultraviolet radiation (UVR exposure*

    Directory of Open Access Journals (Sweden)

    L A. Moore

    2010-12-01

    Full Text Available The development of photokeratitis in response to natural solar ultraviolet radiation (UVR is prevalent in individuals participating in outdoor recreational activities in environments with high reflective surfaces, such as beach activities, water sports and snow skiing. Eye care practitioners (ECPs are frequently encouraged by manufacturers and researchers to recommend UVR-blocking eyewear in the form of sunglasses and contact lenses. However, little is known about the precise nature of the corneal tissue response in the development of photokeratitis. This paper reviews the mechanisms responsible for the development of photokeratitis. Clinical signs and symptoms of photokeratitis, UVR corneal threshold and action spectra, corneal cellular changes and ocular protection from corneal UVR exposure are discussed. The content of this article will be useful to ECPs in making appropriate recommendations when prescribing UVR-protec-tive eyewear. (S Afr Optom 2010 69(3 123-131

  5. Human performance analysis of industrial radiography radiation exposure events

    Energy Technology Data Exchange (ETDEWEB)

    Reece, W.J.; Hill, S.G.

    1995-12-01

    A set of radiation overexposure event reports were reviewed as part of a program to examine human performance in industrial radiography for the US Nuclear Regulatory Commission. Incident records for a seven year period were retrieved from an event database. Ninety-five exposure events were initially categorized and sorted for further analysis. Descriptive models were applied to a subset of severe overexposure events. Modeling included: (1) operational sequence tables to outline the key human actions and interactions with equipment, (2) human reliability event trees, (3) an application of an information processing failures model, and (4) an extrapolated use of the error influences and effects diagram. Results of the modeling analyses provided insights into the industrial radiography task and suggested areas for further action and study to decrease overexposures.

  6. Assessment of health consequences of steel industry welders′ occupational exposure to ultraviolet radiation

    Directory of Open Access Journals (Sweden)

    Zahra Zamanian

    2015-01-01

    Conclusions: This study showed that the time period of UV exposure in welders is higher than the permissible contact threshold level. Therefore, considering the outbreak of the eye and skin disorders in the welders, decreasing exposure time, reducing UV radiation level, and using personal protective equipment seem indispensable. As exposure to UV radiation can be linked to different types of skin cancer, skin aging, and cataract, welders should be advised to decrease their occupational exposures.

  7. Radiation exposure of cardiac sonographers working in an academic noninvasive cardiovascular imaging laboratory.

    Science.gov (United States)

    Velez, Michael R; Orsinelli, Maryellen H; Orsinelli, David A

    2017-09-24

    Exposure to workplace radiation among cardiac sonographers has been felt to be low, and patient-related sources have been considered negligible. Sonographers may be exposed to radiation from patient emitted sources as well as external sources in interventional laboratories. This study quantified radiation exposure to cardiac sonographers. Cardiac sonographers, vascular imaging technologists, exercise physiologists, noninvasive nursing staff, and CT/MRI technologists were provided body dosimeter badges. Sonographers were provided dosimeter rings for their scanning hands. Radiation exposure was quantified from the dosimeter data, reported in millirems (mrem) for deep, eye, and shallow exposure, as well as shallow exposure data from the rings. Data were prospectively collected for 63 employees over a 12-month period and retrospectively analyzed. The mean annual deep body exposure in sonographers was 8.2 mrem/year, shallow exposure 9.8 mrem/year, eye exposure 8.5 mrem/year, and ring exposure 207 mrem/year. There was a significant difference between body and ring exposure (P = .0002). When comparing exposure data between the vascular imaging technologists, CT/MRI technologists, noninvasive nursing staff, and the cardiac sonographers, there were no statistical differences (P > .23). Exercise physiologists had significantly higher exposure compared to sonographers (P exposure is low, cardiac sonographers are exposed to workplace radiation, most likely from patient emitted radiation. The finding that radiation exposure from rings exceeded body exposure supports this conclusion. Continued education and assessment of work flow practices should be employed to minimize staff radiation exposure. © 2017, Wiley Periodicals, Inc.

  8. Long-term differential changes in mouse intestinal metabolomics after γ and heavy ion radiation exposure.

    Directory of Open Access Journals (Sweden)

    Amrita K Cheema

    Full Text Available Tissue consequences of radiation exposure are dependent on radiation quality and high linear energy transfer (high-LET radiation, such as heavy ions in space is known to deposit higher energy in tissues and cause greater damage than low-LET γ radiation. While radiation exposure has been linked to intestinal pathologies, there are very few studies on long-term effects of radiation, fewer involved a therapeutically relevant γ radiation dose, and none explored persistent tissue metabolomic alterations after heavy ion space radiation exposure. Using a metabolomics approach, we report long-term metabolomic markers of radiation injury and perturbation of signaling pathways linked to metabolic alterations in mice after heavy ion or γ radiation exposure. Intestinal tissues (C57BL/6J, female, 6 to 8 wks were analyzed using ultra performance liquid chromatography coupled with electrospray quadrupole time-of-flight mass spectrometry (UPLC-QToF-MS two months after 2 Gy γ radiation and results were compared to an equitoxic ⁵⁶Fe (1.6 Gy radiation dose. The biological relevance of the metabolites was determined using Ingenuity Pathway Analysis, immunoblots, and immunohistochemistry. Metabolic profile analysis showed radiation-type-dependent spatial separation of the groups. Decreased adenine and guanosine and increased inosine and uridine suggested perturbed nucleotide metabolism. While both the radiation types affected amino acid metabolism, the ⁵⁶Fe radiation preferentially altered dipeptide metabolism. Furthermore, ⁵⁶Fe radiation caused upregulation of 'prostanoid biosynthesis' and 'eicosanoid signaling', which are interlinked events related to cellular inflammation and have implications for nutrient absorption and inflammatory bowel disease during space missions and after radiotherapy. In conclusion, our data showed for the first time that metabolomics can not only be used to distinguish between heavy ion and γ radiation exposures, but

  9. Low dose rate gamma ray induced loss and data error rate of multimode silica fibre links; Affaiblissement et taux d`erreur de transmission de fibres optiques multimodes soumises a une irradiation gamma a faible debit de dose

    Energy Technology Data Exchange (ETDEWEB)

    Breuze, G.; Fanet, H.; Serre, J. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Electronique et d`Instrumentation Nucleaire; Colas, D.; Garnero, E.; Hamet, T. [Electricite de France (EDF), 77 - Ecuelles (France)

    1993-12-31

    Fiber optics data transmission from numerous multiplexed sensors, is potentially attractive for nuclear plant applications. Multimode silica fiber behaviour during steady state gamma ray exposure is studied as a joint programme between LETI CE/SACLAY and EDF Renardieres: transmitted optical power and bit error rate have been measured on a 100 m optical fiber.

  10. Aircrew Exposure from Cosmic Radiation on Commercial Airline Routes

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, B.J.; McCall, M.J.; Green, A.R.; Bennett, L.G.I.; Pierre, M.; Schrewe, U.J.; O' Brien, K.; Felsberger, E

    2001-07-01

    As a result of the recent recommendations of the ICRP 60, and in anticipation of possible regulation on occupational exposure of Canadian-based aircrew, an extensive study was carried out by the Royal Military College of Canada over a one-year period to measure the cosmic radiation at commercial jet altitudes. A tissue-equivalent proportional counter was used to measure the ambient total dose equivalent rate on 62 flight routes, resulting in over 20,000 data points at one-minute intervals at various altitudes and geomagnetic latitudes (i.e. which span the full cut-off rigidity of the Earth's magnetic field). These data were then compared to similar experimental work at the Physikalisch Technische Bundesanstalt, using a different suite of equipment, to measure separately the low and high linear energy transfer components of the mixed radiation field, and to predictions with the LUIN transport code. All experimental and theoretical results were in excellent agreement. From these data, a semi-empirical model was developed to allow for the interpolation of the dose rate for any global position, altitude and date (i.e. heliocentric potential). Through integration of the dose rate function over a great circle flight path, a computer code was developed to provide an estimate of the total dose equivalent on any route worldwide at any period in the solar cycle. (author)

  11. Radiation exposure to cardiologists performing interventional cardiology procedures

    Energy Technology Data Exchange (ETDEWEB)

    Delichas, Miltiadis; Psarrakos, Kyriakos; Molyvda-Athanassopoulou, Elisabeth E-mail: moly@med.auth.gr; Giannoglou, Georgios; Sioundas, Anastasios; Hatziioannou, Konstantinos; Papanastassiou, Emmanouil

    2003-12-01

    Medical doctors, who practice interventional cardiology, receive a noticeable radiation dose. In this study, we measured the radiation dose to 9 cardiologists during 144 procedures (72 coronary angiographies and 70 percutaneus translumined coronary angioplasties) in two Greek hospitals. Absorbed doses were measured with TLD placed underneath and over the lead apron at the thyroid protective collar. Based on these measurements, the effective dose was calculated using the Niklason method. In addition, dose area product (DAP) was registered. The effective doses, E, were normalised to the total DAP measured in each procedure, producing the E/DAP index. The mean effective dose values were found to be in the range of 1.2-2.7 {mu}Sv while the mean E/DAP values are in the range of 0.010-0.035 {mu}Sv/Gy cm{sup 2}. The dependence of dose to the X-ray equipment, the exposure parameters and the technique of the cardiologist were examined. Taking under consideration the laboratories' annual workload, the maximum annual dose was estimated to be 1.9 and 2.8 mSv in the two hospitals.

  12. Modeling of secondary radiation damage in LIGA PMMA resist exposure

    Science.gov (United States)

    Ting, Aili

    2003-01-01

    Secondary radiation during LIGA PMMA resist exposure adversely affects feature definition, sidewall taper and overall sidewall offset. Additionally, it can degrade the resist adjacent to the substrate, leading to the loss of free-standing features through undercutting during resist development or through mechanical failure of the degraded material. The source of this radiation includes photoelectrons, Auger electrons, fluorescence photons, etc. Sandia"s Integrated Tiger Series (ITS), a coupled electron/photon Monte Carlo transport code, was used to compute dose profiles within 1 to 2 microns of the absorber edge and near the interface of the resist with a metallized substrate. The difficulty of sub-micron resolution requirement was overcome by solving a few local problems having carefully designed micron-scale geometries. The results indicate a 2-μm dose transition region near the absorber edge resulting from PMMA"s photoelectrons. This region leads to sidewall offset and to tapered sidewalls following resist development. The results also show a dose boundary layer of around 1 μm near the substrate interface due to electrons emitted from the substrate metallization layer. The maximum dose at the resist bottom under the absorber can be very high and can lead to feature loss during development. This model was also used to investigate those resist doses resulting from multi-layer substrate.

  13. Comparison of codes assessing radiation exposure of aircraft crew due to galactic cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bottollier-Depois, Jean-Francois [IRSN Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-Roses (France); Beck, Peter; Latocha, Marcin [AIT Austrian Institute of Technology, Vienna (Austria). Health and Environment Dept.; Mares, Vladimir; Ruehm, Werner [HMGU Helmholtz Zentrum Muenchen, Neuherberg (Germany). Inst. of Radiation Protection; Matthiae, Daniel [DLR Deutsches Zentrum fuer Luft- und Raumfahrt, Koeln (Germany). Inst. of Aerospace Medicine; Wissmann, Frank [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    2012-05-15

    The aim of this report is to compare the doses and dose rates calculated by various codes assessing radiation exposure of aircraft crew due to cosmic radiation. Some of the codes are used routinely for radiation protection purposes while others are purely for scientific use. The calculations were done using a set of representative, real flight routes around the globe. The results are presented in an anonymous way. This comparison is of major importance since a real determination of effective dose is not possible and, therefore, the different methods used to evaluate effective doses can be compared. Eleven codes have been used in this comparison exercise organised by EURADOS on harmonization of aircrew dosimetry practices in European countries. Some of these codes are based on simulations of the secondary field of cosmic radiation by Monte Carlo techniques; others use analytical solutions of the problem, while still others are mainly based on a fit to experimental data. The overall agreement between the codes, however, is better than 20 % from the median.

  14. Application of maximum values for radiation exposure and principles for the calculation of radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The guide sets out the mathematical definitions and principles involved in the calculation of the equivalent dose and the effective dose, and the instructions concerning the application of the maximum values of these quantities. further, for monitoring the dose caused by internal radiation, the guide defines the limits derived from annual dose limits (the Annual Limit on Intake and the Derived Air Concentration). Finally, the guide defines the operational quantities to be used in estimating the equivalent dose and the effective dose, and also sets out the definitions of some other quantities and concepts to be used in monitoring radiation exposure. The guide does not include the calculation of patient doses carried out for the purposes of quality assurance.

  15. Monitoring of increased natural occuring radiation exposure; Arbeitsplatzueberwachung bei erhoehter natuerlicher Strahlenexposition

    Energy Technology Data Exchange (ETDEWEB)

    Guhr, Andreas [ALTRAC Radon-Messtechnik, Berlin (Germany); Leissring, Nick [Bergtechnisches Ingenieurbuero GEOPRAX, Chemnitz (Germany)

    2015-07-01

    The radiation exposure due to natural occurring sources is a special challenge for the health and safety protection at workplaces. The monitoring of the radon exposure of employees in mines, radon-spa and in water works is regulated by prescription of radiation protection. The relevant compounds of the radiation exposure are the inhalation of radon and radon daughter products; terrestrial irradiation; ingestion of radioactive contaminated materials and the inhalation of contaminated dust. The monitoring of the radiation workers is realized essentially by measurements by radiation safety officer of the performing company, by an external engineering firm as well as by control measurements of experts of local authorities. The experiences in the practice have shown that in the field of operational radiation protection only a combination of personal- and operational dosimetry is suitable to avoid health hazards by work in fields with increased natural occurring radiation exposures.

  16. Radiation exposure in nuclear medicine: real-time measurement

    Directory of Open Access Journals (Sweden)

    Iara Sylvain

    2002-09-01

    Full Text Available French regulations have introduced the use of electronic dosimeters for personal monitoring of workers. In order to evaluate the exposure from diagnostic procedures to nuclear medicine staff, individual whole-body doses were measured daily with electronic (digital personal dosimeters during 20 consecutive weeks and correlated with the work load of each day. Personal doses remained always below 20 µSv/d under normal working conditions. Radiation exposure levels were highest to tech staff, nurses and stretcher-bearers. The extrapolated annual cumulative doses for all staff remained less than 10 % of the maximum legal limit for exposed workers (2 mSv/yr. Electronic dosimeters are not technically justified for routine survey of staff. The high sensitivity and immediate reading of electronic semiconductor dosimeters may become very useful for exposure control under risky working conditions. It may become an important help for optimising radiation protection.A legislação francesa introduziu o uso de dosímetros eletrônicos para monitoração da exposição do trabalhador. Afim de avaliar a exposição do trabalhador proveniente de exames diagnósticos em medicina nuclear, doses individuais do corpo inteiro foram medidas diariamente com dosímetros eletrônicos (digitais durante 20 semanas consecutivas e correlatas com as atividades de trabalho de cada dia. As doses foram sempre inferiores à 20 µSv por dia em condições normais de trabalho. Os níveis de exposição de radiação mais elevados foram para os enfermeiros, manipuladores e maqueiros. A extrapolação da dose anual para todos os trabalhadores foi menos que 10 % do limite máximo legal para os trabalhadores expostos (2 mSv/ano. Dosímetros eletrônicos não são tecnicamente justificados para a o controle de rotina da exposição dos trabalhadores, mas a alta sensibilidade e a leitura imediata desses dosímetros podem vir a serem muito úteis para o controle da exposição em condi

  17. Biological effects of low-dose ionizing radiation exposure; Biologische Wirkungen niedriger Dosen ionisierender Strahlung

    Energy Technology Data Exchange (ETDEWEB)

    Reinoehl-Kompa, Sabine; Baldauf, Daniela; Heller, Horst (comps.)

    2009-07-01

    The report on the meeting of the Strahlenschutzkommission 2007 concerning biological effects of low-dose ionizing radiation exposure includes the following contributions: Adaptive response. The importance of DNA damage mechanisms for the biological efficiency of low-energy photons. Radiation effects in mammography: the relative biological radiation effects of low-energy photons. Radiation-induced cataracts. Carcinomas following prenatal radiation exposure. Intercellular apoptosis induction and low-dose irradiation: possible consequences for the oncogenesis control. Mechanistic models for the carcinogenesis with radiation-induced cell inactivation: application to all solid tumors in the Japanese atomic bomb survivors. Microarrays at low radiation doses. Mouse models for the analysis of biological effects of low-dose ionizing radiation. The bystander effect: observations, mechanisms and implications. Lung carcinoma risk of Majak workers - modeling of carcinogenesis and the bystander effect. Microbeam studies in radiation biology - an overview. Carcinogenesis models with radiation-induced genomic instability. Application to two epidemiological cohorts.

  18. Novel protective lead shield and pulse fluoroscopy can reduce radiation exposure during the ERCP procedure.

    Science.gov (United States)

    Kurihara, Toshio; Itoi, Takao; Sofuni, Atsushi; Itokawa, Fumihide; Tsuchiya, Takayoshi; Ishii, Kentaro; Tsuji, Shujiro; Ikeuchi, Nobuhito; Moriyasu, Fuminori

    2012-05-01

    ERCP-related procedures involve radiation exposure of patients and medical staff. We developed a novel protective lead shield which is attached around the fluoroscopy generator. Here we examine levels of radiation exposure to patients, endoscopists and assistants, and evaluate the usefulness of the newly designed protective shield. Four-hundred and seventy-one ERCP procedures were performed from April 2006 to April 2007. At first, we compared the radiation dose of consecutive fluoroscopy conditions with pulse fluoroscopy of 15 per second and then the radiation dose with and without the protective shield. Next, we measured the radiation exposure of endoscopists and assistants in the clinical setting monitored by digital dosimeter during ERCP procedure. The radiation dose was the most at the 45° direction. Using pulse fluoroscopy of 15 per second the radiation dose of patients and endoscopists decreased by about half. Using both pulse fluoroscopy of 15 per second and the protective shield, the radiation dose at the endoscopist's position was reduced up to 97%. The total fluoroscopy time was 5851 minutes in the 471 ERCP cases. Using pulse 15 and the protective lead shield, the radiation exposure dose of one endoscopist and two assistants were 2430.8, 2673.9 and 1375.0µSv, respectively. Novel protective lead shield in combination with pulse fluoroscopy can significantly reduce the radiation exposure leading to avoid unnecessary radiation exposure to patients and medical staff.

  19. 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.

  20. Distribution of Chromosome Breakpoints in Human Epithelial Cells Exposed to Low- and High-LET Radiation

    Science.gov (United States)

    Hada, Megumi; Zhang, Ye; Cucinotta, Francis A.; Feiveson, Alan; Wu, Honglu

    2010-01-01

    Low-and high-LET radiations produced distinct breakpoint distributions. The difference of the breakpoint distributions between low-and high-LET only appeared in break ends involved in interchromosome exchanges. The breakpoint distributions for break ends participating in intrachromosome exchanges were similar. Gene-rich regions do not necessarily have more chromosome breaks. High-LET appeared to produce long live (data not shown) or longer live breaks that can migrate a longer distance before rejoining with other breaks. Domains occupied by different segments of the chromosomes may be responsible for the breakpoint distribution. The dose responses for interchromosomal exchanges were linear in all four exposures. However, the dose response for intrachromosomal exchanges were none linear. Increasing dose of high dose rate exposure (Fe-ions or -rays) increase the fraction of cells with intrachromosome aberrations, whereas increasing dose of low dose rate exposure (neutrons or -rays) does not affect the fraction of cells with intrachromosome aberrations.

  1. Study of radiation exposure dose in young dental patients

    Energy Technology Data Exchange (ETDEWEB)

    Hatakeyama, Atsushi (Fukuoka Dental College, Fukuoka (Japan))

    1983-08-01

    In order to clarify the trend in dental radiography for young patients up to 18 years old and the accompanying radiation exposures, surveys were made at Fukuoka Dental College Hospital and thirty-five dental offices in Fukuoka city and Kitakyushu city. Each kind of radiography increased in average number with age and 16-18 group was given 4.60 times of radiography of one kind or another in the clinic of college hospital. In the dental offices, the number of radiography taken was about one-fourth that of the clinic of college hospital. Although exposure dose varies with exposure factors, distance and angle of exposure, in addition to time factor, were found to affect doses subtly. In the clinic of college hospital the average of estimated doses to organs per person per year were 105.4 mrad (25.2 mrad for 5-year-old children) in the salivary gland, 55.9 mrad (18.9 mrad for 5-year-old) in the thyroid gland, 52.1 mrad (15.0 mrad for 5-year-old) in the lens of the eye and 52.2 mrad (8.7 mrad for 5-year-old) in the sella turcica. In the dental offices, the same average of estimated doses to organs were 40.5 mrad (7.4 mrad for 5-year-old) in the salivary gland, 17.4 mrad (8.0 mrad for 5-year-old) in the thyroid gland, 12.2 mrad (6.1 mrad for 5-year-old) in the lens of eye and 13.1 mrad (1.3 mrad for 5-year-old) in the sella turcica. In all kinds of radiograpy, the estimated doses in genital glands were in ..mu..rad. In the dental offices, both the percentage of young patients to all patients and the radiographing rate were lower as compared with those in the clinic of college hospital. The estimated doses were also lower at one-half to one-fifth and those by age and by organ were found to be one-tenth or lower.

  2. 38 CFR 1.17 - Evaluation of studies relating to health effects of radiation exposure.

    Science.gov (United States)

    2010-07-01

    ... health effects of radiation exposure. (a) From time to time, the Secretary shall publish evaluations of... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Evaluation of studies relating to health effects of radiation exposure. 1.17 Section 1.17 Pensions, Bonuses, and Veterans'...

  3. Mapping the exposure of the Brazilian population to natural background radiation - cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rochedo, Elaine R.R., E-mail: elaine@ird.gov.br [Instituto de Radioprotecao e Dosimetria (lRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Salles, Krause C.S.; Prado, Nadya M.C., E-mail: krausesalles@yahoo.com.br, E-mail: nadya@ime.ib.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    The main objective of this work is to statically and graphically describe the exposure of the Brazilian population to natural background radiation. in this stage, doses due to cosmic rays is being assessed based on sea level dose rates, corrected by latitude and altitude, according to the model recommended by UNSCEAR. In this work, the doses were estimated for ali Brazilian municipalities with more than 100.000 inhabitants. The 253 municipalities selected for this study include about 52% of the Brazilian population. Average dose rate was estimated to be about 50 n Sv/h with a variation coefficient of 31%. The estimated doses have shown a strong influence of altitude on dose rates, with a correlation coefficient of 0,998 for ao exponential fit. This result confirms previous studies that show a large effect of the altitude 00 exposure from cosmic radiation. Considering the same occupation and shielding conditions used by UNSCEAR as global averages, average annual dose was estimated to be 0,37 (0,24 - 0,76) mSv/y, very close to UNSCEAR worldwide average of 0,38 (0,3 - 1,0) mSv/y. (author)

  4. Long-term results of exclusive low-dose rate curie-therapy for a high-grade vaginal intraepithelial neoplasia; Resultats a long terme de la curietherapie exclusive de bas debit de dose pour neoplasie vaginale intraepitheliale de haut grade

    Energy Technology Data Exchange (ETDEWEB)

    Blanchard, P.; Monnier, L.; Dumas, I.; Azoury, F.; Mazeron, R.; Haie-Meder, C. [Institut Gustave-Roussy, 94 - Villejuif (France)

    2010-10-15

    The authors report the results of an exclusive low dose rate curie therapy for female patients treated for a grade 3 vaginal intraepithelial neoplasia. They reviewed the medical files of patients treated since 1983, i.e. 28 women. They analysed demographic characteristics, the clinic description of lesions, possible treatments which occurred before this high-grade vaginal intraepithelial neoplasia, possible previous history of cervical or endometrial cancer, curie therapy detailed data, presence of tumorous relapse. According to that, they conclude that a 60 Gy exclusive low- vaginal dose-rate curie-therapy is an efficient and well tolerated treatment for high-grade vaginal intraepithelial neoplasia. Short communication

  5. Preconception exposure to mutagens: medical and other exposures to radiation and chemicals.

    Science.gov (United States)

    Mulvihill, John J

    2012-07-01

    Contrary to intuition, no environmental exposure has been proved to cause human germ line mutations that manifest as heritable disease in the offspring, not among the children born to survivors of the American atomic bombs in Japan nor in survivors of cancer in childhood, adolescence, or young adulthood who receive intensive chemotherapy, radiotherapy, or both. Even the smallest of recent case series had sufficient statistical power to exclude, with the usual assumptions, an increase as small as 20 % over baseline rates. One positive epidemiologic study of a localized epidemic of Down syndrome in Hungary found an association with periconceptual exposure to a pesticide used in fish farming, trichlorfon. Current population and occupational guidelines to protect against genetic effects of ionizing radiation should continue, with the understanding they are based on extrapolations from mouse experiments and mostly on males. Presently, pre-conceptual counseling for possible germ cell mutation due to the environment can be very reassuring, at least based on, in a sense, the worst-case exposures of cancer survivors. Prudence demands further study. Future work will address the issue with total genomic sequencing and epigenomic analysis.

  6. Dermatopathology effects of simulated solar particle event radiation exposure in the porcine model

    Science.gov (United States)

    Sanzari, Jenine K.; Diffenderfer, Eric S.; Hagan, Sarah; Billings, Paul C.; Gridley, Daila S.; Seykora, John T.; Kennedy, Ann R.; Cengel, Keith A.

    2015-07-01

    The space environment exposes astronauts to risks of acute and chronic exposure to ionizing radiation. Of particular concern is possible exposure to ionizing radiation from a solar particle event (SPE). During an SPE, magnetic disturbances in specific regions of the Sun result in the release of intense bursts of ionizing radiation, primarily consisting of protons that have a highly variable energy spectrum. Thus, SPE events can lead to significant total body radiation exposures to astronauts in space vehicles and especially while performing extravehicular activities. Simulated energy profiles suggest that SPE radiation exposures are likely to be highest in the skin. In the current report, we have used our established miniature pig model system to evaluate the skin toxicity of simulated SPE radiation exposures that closely resemble the energy and fluence profile of the September, 1989 SPE using either conventional radiation (electrons) or proton simulated SPE radiation. Exposure of animals to electron or proton radiation led to dose-dependent increases in epidermal pigmentation, the presence of necrotic keratinocytes at the dermal-epidermal boundary and pigment incontinence, manifested by the presence of melanophages in the derm is upon histological examination. We also observed epidermal hyperplasia and a reduction in vascular density at 30 days following exposure to electron or proton simulated SPE radiation. These results suggest that the doses of electron or proton simulated SPE radiation results in significant skin toxicity that is quantitatively and qualitatively similar. Radiation-induced skin damage is often one of the first clinical signs of both acute and non-acute radiation injury where infection may occur, if not treated. In this report, histopathology analyses of acute radiation-induced skin injury are discussed.

  7. Dermatopathology effects of simulated solar particle event radiation exposure in the porcine model.

    Science.gov (United States)

    Sanzari, Jenine K; Diffenderfer, Eric S; Hagan, Sarah; Billings, Paul C; Gridley, Daila S; Seykora, John T; Kennedy, Ann R; Cengel, Keith A

    2015-07-01

    The space environment exposes astronauts to risks of acute and chronic exposure to ionizing radiation. Of particular concern is possible exposure to ionizing radiation from a solar particle event (SPE). During an SPE, magnetic disturbances in specific regions of the Sun result in the release of intense bursts of ionizing radiation, primarily consisting of protons that have a highly variable energy spectrum. Thus, SPE events can lead to significant total body radiation exposures to astronauts in space vehicles and especially while performing extravehicular activities. Simulated energy profiles suggest that SPE radiation exposures are likely to be highest in the skin. In the current report, we have used our established miniature pig model system to evaluate the skin toxicity of simulated SPE radiation exposures that closely resemble the energy and fluence profile of the September, 1989 SPE using either conventional radiation (electrons) or proton simulated SPE radiation. Exposure of animals to electron or proton radiation led to dose-dependent increases in epidermal pigmentation, the presence of necrotic keratinocytes at the dermal-epidermal boundary and pigment incontinence, manifested by the presence of melanophages in the derm is upon histological examination. We also observed epidermal hyperplasia and a reduction in vascular density at 30 days following exposure to electron or proton simulated SPE radiation. These results suggest that the doses of electron or proton simulated SPE radiation results in significant skin toxicity that is quantitatively and qualitatively similar. Radiation-induced skin damage is often one of the first clinical signs of both acute and non-acute radiation injury where infection may occur, if not treated. In this report, histopathology analyses of acute radiation-induced skin injury are discussed.

  8. Effect of “Noisy” sun conditions on aircrew radiation exposure

    Science.gov (United States)

    Lewis, B. J.; Green, A. R.; Bennett, L. G. I.

    2009-07-01

    In computer codes used to estimate the aircrew radiation exposure from galactic cosmic radiation, a quiet sun model is usually assumed. A revised computer code (PCAIRE ver. 8.0f) is used to calculate the impact of noisy sun conditions on aircrew radiation exposure. The revised code incorporates the effect of solar storm activity, which can perturb the geomagnetic field lines, altering cutoff rigidities and hence the shielding capability of the Earth's magnetic field. The effect of typical solar storm conditions on aircrew radiation exposure is shown to be minimal justifying the usual assumptions.

  9. Radiation exposure in stent-grafting of abdominal aortic aneurysms.

    Science.gov (United States)

    Geijer, H; Larzon, T; Popek, R; Beckman, K-W

    2005-10-01

    In recent years, endovascular stent-grafting of abdominal aortic aneurysms has become more and more common. The radiation dose associated with these procedures is not well documented however. The aim of the present study was to estimate the radiation exposure and to simulate the effects of a switch from C-arm radiographic equipment to a dedicated angiographic suite. Dose-area product (DAP) was recorded for 24 aortic stent-grafting procedures. Based on these data, entrance surface dose (ESD) and effective dose were calculated. A simulation of doses at various settings was also performed using a humanoid Alderson phantom. The image quality was evaluated with a CDRAD contrast-detail phantom. The mean DAP was 72.3 Gy cm(2) at 28 min fluoroscopy time with a mean ESD of 0.39 Gy and a mean effective dose of 10.5 mSv. If the procedures had been performed in an angiographic suite, all dose values would be much higher with a mean ESD of 2.9 Gy with 16 patients exceeding 2 Gy, which is considered to be a threshold for possible skin injury. The image quality for fluoroscopy was superior for the C-arm whilst the angiographic unit gave better acquisition images. Using a C-arm unit resulted in doses similar to percutaneous coronary intervention (PCI). If the same patients had been treated using dedicated angiographic equipment, the risk of skin injury would be much higher. It is thus important to be aware of the dose output of the equipment that is used.

  10. Effects of exposure to different types of radiation on behaviors mediated by peripheral or central systems

    Science.gov (United States)

    Rabin, B. M.; Joseph, J. A.; Erat, S.

    The effects of exposure to ionizing radiation on behavior may result from effects on peripheral or on central systems. For behavioral endpoints that are mediated by peripheral systems (e.g., radiation-induced conditioned taste aversion or vomiting), the behavioral effects of exposure to heavy particles (^56Fe, 600 MeV/n) are qualitatively similar to the effects of exposure to gamma radiation (^60Co) and to fission spectrum neutrons. For these endpoints, the only differences between the different types of radiation are in terms of relative behavioral effectiveness. For behavioral endpoints that are mediated by central systems (e.g., amphetamine-induced taste aversion learning), the effects of exposure to ^56Fe particles are not seen following exposure to lower LET gamma rays or fission spectrum neutrons. These results indicate that the effects of exposure to heavy particles on behavioral endpoints cannot necessarily be extrapolated from studies using gamma rays, but require the use of heavy particles.

  11. Radiation exposure on flights; Strahlenexposition beim Fliegen. Ein Fall fuer den Strahlenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Blettner, Maria [Mainz Univ. (Germany). Inst. fuer Medizinische Biometrie, Epidemiologie und Informatik (IMBEI); Boehm, Theresia; Eberbach, Frieder [Vereinigung Cockpit e.V. Main Airport Center (MAC), Frankfurt (Germany). AG Strahlenschutz; Bottollier-Depois, Jean-Francois [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France); Clairand, Isabelle; Huet, Christelle [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France). Ionizing Radiation Dosimetry Lab.; Frasch, Gerhard [Bundesamt fuer Strahlenschutz, Oberschleissheim/Neuherberg (Germany). Beruflicher Strahlenschutz und Strahlenschutzregister; Hammer, Ga el P. [Laboratoire National de Sante E.P., Dudelange (Luxembourg). Registre Morphologique des Tumeurs; Mares, Vladimir; Ruehm, Werner [Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt GmbH, Neuherberg (Germany); Voelkle, Hansruedi [Fribourg Univ. (Switzerland). Physikdept.

    2014-09-01

    Extend and effects of radiation doses occuring during flights are treated under various aspects. Part of them are, in the first line, radiation exposure of the flying staff and the results of epidemiologic studies regarding the health consequences, as well as aspects of practical radiation protection for the flying staff. Computer programs for dose calculation on flights round off the theme. (orig.)

  12. PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Fallu-Labruyere, A.; Micou, C.; Schulcz, F.; Fellinger, J. [Mirion Technologies - MGPI SA (France)

    2015-07-01

    PRD3000{sup TM} is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, have emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)

  13. Radioisotope-pharmacodynamic studies without exposure to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Graul, H.; Graul, E.H.; Loew, D.; Kunkel, R.

    1983-10-01

    On the basis of a clinico-pharmacological study using a new diuretic combination it is shown that not only the RIA determination, but also the measurement of the total amount of potassium in the body with the aid of the /sup 40/K potassium-nuclide confirmed therapeutic efficacy. Furosemide (30 mg) and the combination furosemide-retard (30 mg) and triamterene (50 mg) influence the plasmarenin-aldosterone system (PRA-system) differently. After both furosemide alone and the combination, the plasma-renin activity increased significantly (p <= 0.05) within the 1st 1.5 hours. While the values rapidly normalized after the combination, the activity after furosemide alone increased significantly up to and after 4.5 h. Approx. 3 h after furosemide the plasma aldosterone concentration increased significantly (p <= 0.05); this was not the case after the combination. Neither potassium in the serum nor the total amount of potassium in the body - measured with the aid of the /sup 40/K potassium nuclide - decreased after 8 days of treatment with the combination of furosemide-retard and triamterene. Both methods have proved of value in the clinico-pharmacological examination of diuretics. They are of great importance, easy to apply, involve no exposure to radiation, and are inexpensive.

  14. Functional status of liverin conditions of radiation and chemical exposure

    Directory of Open Access Journals (Sweden)

    O. V. Severynovs’ka

    2005-09-01

    Full Text Available Chronic influences of low-intensity X-rays in doses of 0.15 and 0.25 Gr and mix of heavy metals salts in a dose of 2 EPC (extreme permissible concentrations for each metal, as a single factor or as a combination of factors, on the state of pro-/antioxidative system in a rat liver have been studied. Analysis of the data concerning combined influences allows to conclude that effects under these doses have some differences: a splash of processes of lipid peroxidation are observed in both causes, but under the lower dose an additivity takes place, and under the dose of 0.25 Gr a synergism of the agent effects in relation to the development of peroxidative reactions is registered. The results testify that technogenic contamination of water with heavy metals worsens the action of radiation factor, specifically, eliminates a hormetic splash of antioxidative activity at 0.15 Gr. Biochemical indexes of the liver activity, as a central organ of a general metabolism, and a structure of morbidity have been studied in liquidators of the Chernobyl accident from industrial Prydnieprovie region. Disturbances of liver functions have been shown, especially in persons obtained the exposure dose about 0.25 Gr. A comparison of these results and data of tests with laboratory animals reveals their mutual accordance and supports a relevancy of extrapolation of data of model experiments on a person health state, which undergone a similar influence.

  15. Is ultraviolet radiation a synergistic stressor in combined exposures? The case study of Daphnia magna exposure to UV and carbendazim.

    Science.gov (United States)

    Ribeiro, Fabianne; Ferreira, Nuno C G; Ferreira, Abel; Soares, Amadeu M V M; Loureiro, Susana

    2011-03-01

    The toxicological assessment of chemical compounds released to the environment is more accurate when mixtures of chemicals and/or interactions between chemicals and natural stressors are considered. Ultraviolet radiation can be taken as a natural stressor since the levels of UV are increasing due to the decrease of its natural filter, the stratospheric ozone concentration. Therefore, a combination of chemical exposures and increasing UV irradiance in aquatic environments is likely to occur. In the current study, combined effects of carbendazim and ultraviolet radiation were evaluated, using selected life traits as endpoints on Daphnia magna. To design combined exposures, first single chemical and natural stressor bioassays were performed: a reproduction test with carbendazim and a reproduction, feeding inhibition and Energy budget test with ultraviolet radiation. Following single exposures, the combinations of stressors included exposures to UV radiation and carbendazim for a maximum exposure time of 4h, followed by a post-exposure period in chemically contaminated medium for a maximum of 15 days, depending on the endpoint, where the effects of the combined exposures were investigated. Statistical analyses of the data set were performed using the MixTox tool and were based on the conceptual model of Independent Action (IA) and possible deviations to synergism or antagonism, dose-ratio or dose-level response pattern. Both ultraviolet radiation and carbendazim as single stressors had negative impacts on the measured life traits of daphnids, a decrease on both feeding rates and reproduction was observed. Feeding rates and reproduction of D. magna submitted to combined exposures of ultraviolet radiation and carbendazim showed a dose-ratio deviation from the conceptual model as the best description of the data set, for both endpoints. For feeding inhibition, antagonism was observed when the UV radiation was the dominant item in combination, and for reproduction

  16. [Combined radiation exposures and their immediate and late sequelae].

    Science.gov (United States)

    Gogin, E E

    1990-01-01

    The author reviews correlations between the general and local processes and criteria for the diagnosis of acute radiation sickness (acute radiation syndrome) /ARS/ as well as other clinical sequels of radiation injury (radiation burns, abnormalities of critical organ function, stochastic sequels) induced by total even and uneven radiation and concomitant radiation effects. Based on the own observations the coefficients were defined of private correlations of the doses of the total gamma- and high-absorbable ("soft") components of concomitant radiation effects on the content of neutrophil leukocytes in peripheral blood seen during successive transformations of the development of ARS and the subclinical forms of radiation injury. The main characteristic features of ARS induced by concomitant radiation injury as a result of nuclear reactor break down have been formulated.

  17. MicroRNA Expression Profiling Altered by Variant Dosage of Radiation Exposure

    Directory of Open Access Journals (Sweden)

    Kuei-Fang Lee

    2014-01-01

    Full Text Available Various biological effects are associated with radiation exposure. Irradiated cells may elevate the risk for genetic instability, mutation, and cancer under low levels of radiation exposure, in addition to being able to extend the postradiation side effects in normal tissues. Radiation-induced bystander effect (RIBE is the focus of rigorous research as it may promote the development of cancer even at low radiation doses. Alterations in the DNA sequence could not explain these biological effects of radiation and it is thought that epigenetics factors may be involved. Indeed, some microRNAs (or miRNAs have been found to correlate radiation-induced damages and may be potential biomarkers for the various biological effects caused by different levels of radiation exposure. However, the regulatory role that miRNA plays in this aspect remains elusive. In this study, we profiled the expression changes in miRNA under fractionated radiation exposure in human peripheral blood mononuclear cells. By utilizing publicly available microRNA knowledge bases and performing cross validations with our previous gene expression profiling under the same radiation condition, we identified various miRNA-gene interactions specific to different doses of radiation treatment, providing new insights for the molecular underpinnings of radiation injury.

  18. Patient exposure and radiation environment of an extracorporeal shock wave lithotriptor system

    Energy Technology Data Exchange (ETDEWEB)

    Lin, P.J.; Hrejsa, A.F.

    1987-10-01

    Radiation exposures to the patient undergoing extracorporeal shock wave lithotripsy were assessed along with the scattered radiation levels around the lithotriptor systems. The data gathered from 2 Dornier lithotriptor systems suggest that the lead shieldings required for this particular make and model are minimal. Owing to the physical size of the lithotriptor system, the treatment room housing it may not require additional lead shielding when the walls are constructed with appropriate materials. Typical radiation exposures to the patient have been assessed from the experimental data. The total amount of radiation exposures a patient is likely to receive has been estimated to be approximately 26 roentgens, for example 21 roentgens from 3 to 4 minutes of fluoroscopic exposure and 5 roentgens from 8 frames of video spot filming. The scattered radiation has been found to be approximately 0.5 mR. per hour at 3 feet or 91 cm. from the center of the lithotriptor water tank.

  19. Review: Weak radiofrequency radiation exposure from mobile phone radiation on plants.

    Science.gov (United States)

    Halgamuge, Malka N

    2017-01-01

    The aim of this article was to explore the hypothesis that non-thermal, weak, radiofrequency electromagnetic fields (RF-EMF) have an effect on living plants. In this study, we performed an analysis of the data extracted from the 45 peer-reviewed scientific publications (1996-2016) describing 169 experimental observations to detect the physiological and morphological changes in plants due to the non-thermal RF-EMF effects from mobile phone radiation. Twenty-nine different species of plants were considered in this work. Our analysis demonstrates that the data from a substantial amount of the studies on RF-EMFs from mobile phones show physiological and/or morphological effects (89.9%, p plants seem to be very sensitive to RF-EMFs. Our findings also suggest that plants seem to be more responsive to certain frequencies, especially the frequencies between (i) 800 and 1500 MHz (p plants to date observed the significant trend of radiofrequency radiation influence on plants. Hence, this study provides new evidence supporting our hypothesis. Nonetheless, this endorses the need for more experiments to observe the effects of RF-EMFs, especially for the longer exposure durations, using the whole organisms. The above observation agrees with our earlier study, in that it supported that it is not a well-grounded method to characterize biological effects without considering the exposure duration. Nevertheless, none of these findings can be directly associated with human; however, on the other hand, this cannot be excluded, as it can impact the human welfare and health, either directly or indirectly, due to their complexity and varied effects (calcium metabolism, stress proteins, etc.). This study should be useful as a reference for researchers conducting epidemiological studies and the long-term experiments, using whole organisms, to observe the effects of RF-EMFs.

  20. Gene expression signatures that predict radiation exposure in mice and humans.

    Directory of Open Access Journals (Sweden)

    Holly K Dressman

    2007-04-01

    Full Text Available BACKGROUND: The capacity to assess environmental inputs to biological phenotypes is limited by methods that can accurately and quantitatively measure these contributions. One such example can be seen in the context of exposure to ionizing radiation. METHODS AND FINDINGS: We have made use of gene expression analysis of peripheral blood (PB mononuclear cells to develop expression profiles that accurately reflect prior radiation exposure. We demonstrate that expression profiles can be developed that not only predict radiation exposure in mice but also distinguish the level of radiation exposure, ranging from 50 cGy to 1,000 cGy. Likewise, a molecular signature of radiation response developed solely from irradiated human patient samples can predict and distinguish irradiated human PB samples from nonirradiated samples with an accuracy of 90%, sensitivity of 85%, and specificity of 94%. We further demonstrate that a radiation profile developed in the mouse can correctly distinguish PB samples from irradiated and nonirradiated human patients with an accuracy of 77%, sensitivity of 82%, and specificity of 75%. Taken together, these data demonstrate that molecular profiles can be generated that are highly predictive of different levels of radiation exposure in mice and humans. CONCLUSIONS: We suggest that this approach, with additional refinement, could provide a method to assess the effects of various environmental inputs into biological phenotypes as well as providing a more practical application of a rapid molecular screening test for the diagnosis of radiation exposure.

  1. 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)

  2. NASA Space Radiation Protection Strategies: Risk Assessment and Permissible Exposure Limits

    Science.gov (United States)

    Huff, J. L.; Patel, Z. S.; Simonsen, L. C.

    2017-01-01

    Permissible exposure limits (PELs) for short-term and career astronaut exposures to space radiation have been set and approved by NASA with the goal of protecting astronauts against health risks associated with ionizing radiation exposure. Short term PELs are intended to prevent clinically significant deterministic health effects, including performance decrements, which could threaten astronaut health and jeopardize mission success. Career PELs are implemented to control late occurring health effects, including a 3% risk of exposure induced death (REID) from cancer, and dose limits are used to prevent cardiovascular and central nervous system diseases. For radiation protection, meeting the cancer PEL is currently the design driver for galactic cosmic ray and solar particle event shielding, mission duration, and crew certification (e.g., 1-year ISS missions). The risk of cancer development is the largest known long-term health consequence following radiation exposure, and current estimates for long-term health risks due to cardiovascular diseases are approximately 30% to 40% of the cancer risk for exposures above an estimated threshold (Deep Space one-year and Mars missions). Large uncertainties currently exist in estimating the health risks of space radiation exposure. Improved understanding through radiobiology and physics research allows increased accuracy in risk estimation and is essential for ensuring astronaut health as well as for controlling mission costs, optimization of mission operations, vehicle design, and countermeasure assessment. We will review the Space Radiation Program Element's research strategies to increase accuracy in risk models and to inform development and validation of the permissible exposure limits.

  3. Occupational hazard: radiation exposure for the urologist--developing a reference standard.

    Science.gov (United States)

    Cohen, Seth A; Rangarajan, Sriram S; Chen, Tony; Palazzi, Kerrin L; Langford, J Scott; Sur, Roger L

    2013-01-01

    To date, there is a paucity of literature offering practicing urologists a reference for the amount of radiation exposure received while surgically managing urolithiasis. This study examines the cumulative radiation exposure of an urologist over 9 months. We present a case series of fluoroscopic exposures of an experienced stone surgeon operating at an academic comprehensive stone center between April and December 2011. Radiation exposure measurements were determined by a thermoluminescent dosimeter worn on the outside of the surgeon's thyroid shield. Estimations of radiation exposure (mrem) per month were charted with fluoroscopy times, using scatter plots to estimate Spearman's rank correlation coefficients. The total 9-month radiation exposure was 87 mrems for deep dose equivalent (DDE), 293 mrem for lens dose equivalent (LDE), and 282 mrem for shallow dose equivalent (SDE). Total fluoroscopy time was 252.44 minutes for 64 ureteroscopies (URSs), 29 percutaneous nephrolithtomies (PNLs), 20 cystoscopies with ureteral stent placements, 9 shock wave lithotripsies (SWLs), 9 retrograde pyelograms (RPGs), 2 endoureterotomies, and 1 ureteral balloon dilation. Spearman's rank correlation coefficients examining the association between fluoroscopy time and radiation exposure were not significant for DDE (p = 0.6, Spearman's rho = 0.2), LDE (p = 0.6, Spearman's rho = 0.2), or SDE (p = 0.6, Spearman's rho = 0.2). Over a 9-month period, total radiation exposures were well below annual accepted limits (DDE 5000 mrem, LDE 15,000 mrem and SDE 50,000 mrem). Although fluoroscopy time did not correlate with radiation exposure, future prospective studies can account for co-variates such as patient obesity and urologist distance from radiation source.

  4. Occupational Hazard: Radiation Exposure for the Urologist – Developing a Reference Standard

    Directory of Open Access Journals (Sweden)

    Seth A. Cohen

    2013-04-01

    Full Text Available Introduction To date, there is a paucity of literature offering practicing urologists a reference for the amount of radiation exposure received while surgically managing urolithiasis. This study examines the cumulative radiation exposure of an urologist over 9 months. Materials and Methods We present a case series of fluoroscopic exposures of an experienced stone surgeon operating at an academic comprehensive stone center between April and December 2011. Radiation exposure measurements were determined by a thermoluminescent dosimeter worn on the outside of the surgeon's thyroid shield. Estimations of radiation exposure (mrem per month were charted with fluoroscopy times, using scatter plots to estimate Spearman's rank correlation coefficients. Results The total 9-month radiation exposure was 87 mrems for deep dose equivalent (DDE, 293 mrem for lens dose equivalent (LDE, and 282 mrem for shallow dose equivalent (SDE. Total fluoroscopy time was 252.44 minutes for 64 ureteroscopies (URSs, 29 percutaneous nephrolithtomies (PNLs, 20 cystoscopies with ureteral stent placements, 9 shock wave lithotripsies (SWLs, 9 retrograde pyelograms (RPGs, 2 endoureterotomies, and 1 ureteral balloon dilation. Spearman's rank correlation coefficients examining the association between fluoroscopy time and radiation exposure were not significant for DDE (p = 0.6, Spearman's rho = 0.2, LDE (p = 0.6, Spearman's rho = 0.2, or SDE (p = 0.6, Spearman's rho = 0.2. Conclusions Over a 9-month period, total radiation exposures were well below annual accepted limits (DDE 5000 mrem, LDE 15,000 mrem and SDE 50,000 mrem. Although fluoroscopy time did not correlate with radiation exposure, future prospective studies can account for co-variates such as patient obesity and urologist distance from radiation source.

  5. Occupational hazard: radiation exposure for the urologist: developing a reference standard

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Seth A.; Rangarajan, Sriram S.; Chen, Tony; Palazzi, Kerrin L.; Langford, J. Scott; Sur, Roger L., E-mail: rlsur@ucsd.edu [Department of Surgery and Division of Urology, U C San Diego Health Science System, San Diego, CA (United States)

    2013-03-15

    Introduction: to date, there is a paucity of literature offering practicing urologists a reference for the amount of radiation exposure received while surgically managing urolithiasis. This study examines the cumulative radiation exposure of an urologist over 9 months. Materials and methods: We present a case series of fluoroscopic exposures of an experienced stone surgeon operating at an academic comprehensive stone center between April and December 2011. Radiation exposure measurements were determined by a thermoluminescent dosimeter worn on the outside of the surgeon's thyroid shield. Estimations of radiation exposure (mrem) per month were charted with fluoroscopy times, using scatter plots to estimate Spearman's rank correlation coefficients. Results: the total 9-month radiation exposure was 87 mrems for deep dose equivalent (DDE), 293 mrem for lens dose equivalent (LDE), and 282 mrem for shallow dose equivalent (SDE). Total fluoroscopy time was 252.44 minutes for 64 ureteroscopies (URSs), 29 percutaneous nephrolithtomies (PNLs), 20 cystoscopies with ureteral stent placements, 9 shock wave ithotripsies (SWLs), 9 retrograde pyelograms (RPGs), 2 endoureterotomies, and 1 ureteral balloon dilation. Spearman's rank correlation coefficients examining the association between fluoroscopy time and radiation exposure were not significant for DDE (p = 0.6, Spearman's rho = 0.2), LDE (p = 0.6, Spearman's rho = 0.2), or SDE (p = 0.6, Spearman's rho = 0.2). Conclusions: Over a 9-month period, total radiation exposures were well below annual accepted limits (DDE 5000 mrem, LDE 15,000 mrem and SDE 50,000 mrem). Although fluoroscopy time did not correlate with radiation exposure, future prospective studies can account for co-variates such as patient obesity and urologist distance from radiation source. (author)

  6. Analysis of chronic radiation exposure at small doses

    Energy Technology Data Exchange (ETDEWEB)

    Krestinina, L.Y. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation)

    2000-05-01

    The purpose of the study was to analyze the late effects of radiation exposure among residents of settlements located on the territory of the East-Urals Radiation Trace (EURT) in the Southern Urals. In 1957 an explosion occurred at the depot of radioactive waste in the Southern Urals. An area of 23000 km{sup 2} was contaminated, with contamination density of over 0.1 Ci/m{sup 2} for {sup 90}Sr. There were 217 populated ares on that territory with total population about 270000. The residents of 22 villages with contamination density of over 4 Ci/km{sup 2} for {sup 90}Sr were evacuated. The times of evacuation differed from 7 to 670 days since the accident, depending on the level of contamination. In 1988-1993 an individualized registry was created at the Urals Research Center for Radiation Medicine (URCRM) which included information on the residents of 22 evacuated villages and a proportion of unevacuated residents of the EURT area. Currently, the registry contains data on 30000 residents. Of that number 17000 persons were born before, and 12000 after the accident (including about 9000 offspring of exposed residents evacuated from the EURT, and about 3000 persons who were born after the accident and have been living permanently in the EURT area). Over the 35-year period since the accident the residents have received mean effective doses ranging from 23 to 530 mSv. The mean effective doses received by permanent residents range from 5 to 60 mSv. The cohort of people exposed on the EURT territory was identified based on the information contained in the registry. If a person happened to be in the EURT area at the time of the accident, he/she was considered to be eligible for inclusion in the cohort. Over the 35-year period (from 1957 through 1992) 29.5% of 17872 residents died, and 35% of the original cohort were lost to follow-up for different reasons. To enable an analysis a control group was established which included residents of villages located outside, but close

  7. Reaction of fresh water zooplankton community to chronic radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Osipov, D.; Pryakhin, E. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation); Ivanov, I. [FSUE Mayak PA (Russian Federation)

    2014-07-01

    The characteristic features of ecological community as a whole and cenosis of zooplankton organisms as part of it determine the intensity of the processes of self-purification of water and the formation of a particular body of water. Identifying features of the structure and composition of the zooplankton community of aquatic ecosystems exposed to different levels of radiation exposure, it is necessary to identify patterns of changes in zooplankton and hydro-biocenosis as a whole. Industrial reservoirs, the storage of liquid low-level radioactive waste 'Mayak' for decades, have high radiation load. A large range of levels of radioactive contamination (total volume beta-activity in water varies from 2.2x10{sup 3} to 2.3x10{sup 7} Bq/l, total volume alpha-activity - from 2.6x10{sup -1} to 3.1x10{sup 3} Bq/l) provides a unique opportunity to study ecosystems in a number of reservoirs with increasing impact of radiation factor. We studied five reservoirs that were used as the storage of low-and intermediate-level liquid radioactive waste pond and one comparison water body. In parallel with zooplankton sampling water samples were collected for hydro-chemical analysis. 41 indicators were analysed in order to assess the water chemistry. To determine the content of radionuclides in the various components of the ecosystem samples were collected from water, bottom sediments and plankton. Sampling of zooplankton for the quantitative analysis was performed using the method of weighted average auto bathometer. Apshteyn's plankton net of the surface horizon was used for qualitative analysis of the species composition of zooplankton. Software package ERICA Assessment Tool 2012 was used for the calculation of the absorbed dose rate. Species diversity and biomass of zooplankton, the share of rotifers in the number of species, abundance and biomass decrease with the increase of the absorbed dose rate and salinity. The number of species in a sample decreases with the

  8. Radiation exposure reduction by use of Kevlar cassettes in the neonatal nursery.

    Science.gov (United States)

    Herman, M W; Mak, H K; Lachman, R S

    1987-05-01

    A study was performed to determine whether the use of Kevlar cassettes in the neonatal intensive care nursery would reduce radiation exposure to patients. The radiation dose to the neonates was measured by using thermoluminescent dosimeters. In addition, the attenuation of the Kevlar cassettes and the sensitivity of the film-screen combination were compared with the previously used system. The greatest radiation reduction using a mobile X-ray unit was 27%; based on sensitivity measurements, the theoretical reduction averaged 38%. The reduction in radiation exposure resulted from reduced attenuation by the Kevlar cassette.

  9. Health risks associated with low dose diagnostic or therapeutic radiation exposures

    Energy Technology Data Exchange (ETDEWEB)

    Boreham, D.R. [McMaster Univ., Dept. of Medical Physics and Applied Radiation Sciences, Hamilton, Ontario (Canada)

    2007-07-01

    The health risks to humans associated with exposure to low doses of ionizing radiation have been extrapolated from effects observed at high doses, dose rates, and mixed radiation qualities using a linear no threshold model. Based on this approach, it has been argued that human exposure to low doses of diagnostics X-rays and gamma-rays increase an individual's risk of developing cancer throughout their life-time. Also, repeated medical diagnostic procedures involving low dose exposures will have an additive effect and consequently further increase health risk. The specific aim of this seminar will be to address the relative risk associated with diagnostic X-rays from CT scans and gamma-rays from positron emission tomography (PET) scans. Objectives of the talk will include: 1) Defining low dose exposures at a cellular level and relate that to diagnostic or therapeutic exposures, 2) Describing modern tools in molecular cytogenetics to estimate radiation exposure and assess radiation risk, 3) Identifying the different cellular mechanisms that influence radiation risk at high and low dose exposures and relate that to individual radiation risk. (author)

  10. Radiation Protection Challenges for a Human Mission to Mars

    Science.gov (United States)

    Zeitlin, C. J.; Hassler, D.; Wimmer-Schweingruber, R. F.; Schwadron, N.; Spence, H. E.

    2015-12-01

    A human mission to Mars presents many challenges, not least of which is the radiation exposure that crew members will certainly receive in all phases of the journey, but most critically during the transits to and from Mars. Measurements from the Radiation Assessment Detector (RAD) aboard the Mars Science Laboratory Curiosity rover, made both in flight and on the surface of Mars, confirm previous estimates that crew members under reasonable shielding would receive a dose equivalent of about 1 Sievert on a 1000-day mission. In standard radiation biology, an acute exposure to 1 Sievert would be expected to increase lifetime fatal cancer risk by about 5%. This is well beyond the currently allowed 3% risk increase limit used by NASA and JAXA. Perhaps more significantly, the nature of exposure in space differs greatly from the terrestrial exposures that lead to the 5% estimate -- in space, the exposure is received at a very low dose rate, and includes a significant component from heavy ions in the Galactic Cosmic Rays (GCRs). Acute exposures to Solar Energetic Particles are also possible, but the generally lower energies of SEPs (kinetic energies typically below 100 MeV/nuc) mean that modest amounts of shielding are effective against them. Thus the greater concern for long-duration deep-space missions is the GCR exposure. In this presentation, I will briefly review the MSL-RAD data and discuss current approaches to radiation risk estimation, including the NASA limit of 3% at the 95% confidence level. Recent results from the NASA radiation biology program indicate that cancer may not be the only risk that needs to be considered, with emerging concerns about cardiovascular and central nervous system health. These health effects are not accounted for in the current methodology and could potentially be threatening to mission success if they manifest in the course of the mission, rather than appearing many years after the exposure as radiation-induced cancer typically does.

  11. Evaluation of the cloudy sky solar UVA radiation exposures.

    Science.gov (United States)

    Parisi, A V; Downs, N; Turner, J

    2014-09-05

    The influence of cloud on the solar UVA (320-400 nm) exposures over five minute periods on a horizontal plane has been investigated. The first approach used cloud modification factors that were evaluated using the influence of clouds on the global solar exposures (310-2800 nm) and a model developed to apply these to the clear sky UVA exposures to allow calculation of the five minute UVA exposures for any cloud conditions. The second approach established a relationship between the UVA and the global solar exposures. The models were developed using the first six months of data in 2012 for SZA less than or equal to 70° and were applied and evaluated for the exposures in the second half of 2012. This comparison of the modelled exposures for all cloud conditions to the measured data provided an R(2) of 0.8 for the cloud modification model, compared to an R(2) of 0.7 for the UVA/global model. The cloud modification model provided 73% of the five minute exposures within 20% of the measured UVA exposures. This was improved to 89% of the exposures within 20% of the measured UVA exposures for the cases of cloud with the sun not obscured.

  12. Radiation effects in concrete for nuclear power plants – Part I: Quantification of radiation exposure and radiation effects

    Energy Technology Data Exchange (ETDEWEB)

    Field, K.G., E-mail: fieldkg@ornl.gov; Remec, I.; Pape, Y. Le

    2015-02-15

    Highlights: • Neutron and gamma rays fields in concrete biological shield are calculated. • An extensive database on irradiated concrete properties has been collected. • Concrete mechanical properties decrease beyond 1.0 × 10{sup 19} n/cm{sup 2} fluence. • Loss of properties appears correlated with radiation induced-aggregate swelling. • Commercial reactor bio-shield may experience long-term irradiation damage. - Abstract: A large fraction of light water reactor (LWR) construction utilizes concrete, including safety-related structures such as the biological shielding and containment building. Concrete is an inherently complex material, with the properties of concrete structures changing over their lifetime due to the intrinsic nature of concrete and influences from local environment. As concrete structures within LWRs age, the total neutron fluence exposure of the components, in particular the biological shield, can increase to levels where deleterious effects are introduced as a result of neutron irradiation. This work summarizes the current state of the art on irradiated concrete, including a review of the current literature and estimates the total neutron fluence expected in biological shields in typical LWR configurations. It was found a first-order mechanism for loss of mechanical properties of irradiated concrete is due to radiation-induced swelling of aggregates, which leads to volumetric expansion of the concrete. This phenomena is estimated to occur near the end of life of biological shield components in LWRs based on calculations of estimated peak neutron fluence in the shield after 80 years of operation.

  13. Mathematical Models of Human Hematopoiesis Following Acute Radiation Exposure

    Science.gov (United States)

    2014-05-01

    the model predicts. Radiation dose from skin contamination can result in cutaneous injury leading to systemic responses and may im- pact the observed...medical and performance consequences from radiation and combined injuries , thereby enhancing our understanding of the potential impact of a nuclear...subsequently. In addition to the insight gained from combined injury modeling, the models of hematopoiesis and radiation alone provide clini- cally

  14. Estimates of Radiation Effects on Cancer Risks in the Mayak Worker, Techa River and Atomic Bomb Survivor Studies.

    Science.gov (United States)

    Preston, Dale L; Sokolnikov, Mikhail E; Krestinina, Lyudmila Yu; Stram, Daniel O

    2017-04-01

    For almost 50 y, the Life Span Study cohort of atomic bomb survivor studies has been the primary source of the quantitative estimates of cancer and non-cancer risks that form the basis of international radiation protection standards. However, the long-term follow-up and extensive individual dose reconstruction for the Russian Mayak worker cohort (MWC) and Techa River cohort (TRC) are providing quantitative information about radiation effects on cancer risks that complement the atomic bomb survivor-based risk estimates. The MWC, which includes ~26 000 men and women who began working at Mayak between 1948 and 1982, is the primary source for estimates of the effects of plutonium on cancer risks and also provides information on the effects of low-dose rate external gamma exposures. The TRC consists of ~30 000 men and women of all ages who received low-dose-rate, low-dose exposures as a consequence of Mayak's release of radioactive material into the Techa River. The TRC data are of interest because the exposures are broadly similar to those experienced by populations exposed as a consequence of nuclear accidents such as Chernobyl. In this presentation, it is described the strengths and limitations of these three cohorts, outline and compare recent solid cancer and leukemia risk estimates and discussed why information from the Mayak and Techa River studies might play a role in the development and refinement of the radiation risk estimates that form the basis for radiation protection standards. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Exposure to ionizing radiation induced persistent gene expression changes in mouse mammary gland

    Directory of Open Access Journals (Sweden)

    Datta Kamal

    2012-12-01

    Full Text Available Abstract Background Breast tissue is among the most sensitive tissues to the carcinogenic actions of ionizing radiation and epidemiological studies have linked radiation exposure to breast cancer. Currently, molecular understanding of radiation carcinogenesis in mammary gland is hindered due to the scarcity of in vivo long-term follow up data. We undertook this study to delineate radiation-induced persistent alterations in gene expression in mouse mammary glands 2-month after radiation exposure. Methods Six to eight week old female C57BL/6J mice were exposed to 2 Gy of whole body γ radiation and mammary glands were surgically removed 2-month after radiation. RNA was isolated and microarray hybridization performed for gene expression analysis. Ingenuity Pathway Analysis (IPA was used for biological interpretation of microarray data. Real time quantitative PCR was performed on selected genes to confirm the microarray data. Results Compared to untreated controls, the mRNA levels of a total of 737 genes were significantly (p Conclusions Exposure to a clinically relevant radiation dose led to long-term activation of mammary gland genes involved in proliferative and metabolic pathways, which are known to have roles in carcinogenesis. When considered along with downregulation of a number of tumor suppressor genes, our study has implications for breast cancer initiation and progression after therapeutic radiation exposure.

  16. Cell/Tissue Culture Radiation Exposure Facility Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the development of automated systems to improve radiobiology research capabilities at NASA Space Radiation Laboratory (NSRL) at Brookhaven National...

  17. Effect of Radiation Exposure on the Retention of Commercial NAND Flash Memory

    Science.gov (United States)

    Oldham, Timothy R.; Chen, D.; Friendlich, M.; Carts, M. A.; Seidleck, C. M.; LaBel, K. A.

    2011-01-01

    We have compared the data retention of irradiated commercial NAND flash memories with that of unirradiated controls. Under some circumstanc es, radiation exposure has a significant effect on the retention of f lash memories.

  18. Atomic oxygen and ultraviolet radiation mission total exposures for LDEF experiments

    Science.gov (United States)

    Bourassa, R. J.; Gillis, J. R.; Rousslang, Ken W.

    1992-01-01

    Atomic oxygen and solar radiation exposures were determined analytically for rows, longerons, and end bays of the LDEF. Calculated atomic oxygen exposures are based on an analytical model that accounts for the effects of thermal molecular velocity, atmospheric temperature, number density, spacecraft velocity, incidence angle, and atmospheric rotation. Results also incorporate variations in solar activity, geomagnetic index, and orbital parameters occurring over the six year flight of the spacecraft. Solar radiation exposure calculations are based on the form factors reported in the Solar Illumination Data Package prepared by NASA Langley. The earth albedo value for these calculations was based on the Nimbus 7 earth radiation data set. Summary charts for both atomic oxygen and solar radiation exposure are presented to facilitate the use of the data generated by LDEF experimenters.

  19. Radiation dose evaluation based on exposure scenario during the operation of radioactive waste disposal facility

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jeong Hyoun; Kim Chang Lak; Choi, Heui Joo; Park, Joo Wan [Korea Electric Power Corporation, Nuclear Environment Technology Institute, Taejon (Korea, Republic of)

    1999-07-01

    Radiation dose to worker in disposal facility was calculated by using point kernel MICROSHIELD V5.02 computer code based on exposure scenarios. An conceptual design model for disposal vaults in disposal facility was used for object of shielding calculation model. Selected radionuclides and their activities among radioactive wastes from nuclear power plants were assumed as radiation sources for the exposure calculation. Annual radiation doses to crane workers and to people working on disposal vaults were calculated according to exposure time and distance from the sources with conservative operation scenarios. The scenarios used for this study were based on assumption for representing disposal activities in a future Korean near surface disposal facility. Calculated exposure rates to worker during normal disposal work were very low comparing with annual allowable limit for radiation worker.

  20. Inside the Meteorite — Bacterial Spore Survival After Exposure to Galactic Cosmic Radiation

    Science.gov (United States)

    Moeller, R.; Berger, T.; Matthiä, D.; Okayasu, R.; Kato, T.; Kitamura, H.; Reitz, G.

    2010-04-01

    Based on their unique resistance to various space parameters, bacterial spores are one of the model systems used for astrobiological studies. In our research, we studied the response of Bacillus subtilis spores to the exposure of galactic cosmic radiation.

  1. Medical exposure to ionising radiation and the risk of brain tumours

    DEFF Research Database (Denmark)

    Blettner, Maria; Schlehofer, Brigitte; Samkange-Zeeb, Florence

    2007-01-01

    BACKGROUND: The role of exposure to low doses of ionising radiation in the aetiology of brain tumours has yet to be clarified. The objective of this study was to investigate the association between medically or occupationally related exposure to ionising radiation and brain tumours. METHODS: We...... used self-reported medical and occupational data collected during the German part of a multinational case-control study on mobile phone use and the risk of brain tumours (Interphone study) for the analyses. RESULTS: For any exposure to medical ionising radiation we found odds ratios (ORs) of 0.63 (95...... regions. CONCLUSION: We did not find any significant increased risk of brain tumours for exposure to medical ionising radiation....

  2. The Risk of Radiation Exposure to the Eyes of the Interventional Pain Physician

    Directory of Open Access Journals (Sweden)

    David E. Fish

    2011-01-01

    Full Text Available It is widely accepted that the use of medical imaging continues to grow across the globe as does the concern for radiation safety. The danger of lens opacities and cataract formation related to radiation exposure is well documented in the medical literature. However, there continues to be controversy regarding actual dose thresholds of radiation exposure and whether these thresholds are still relevant to cataract formation. Eye safety and the risk involved for the interventional pain physician is not entirely clear. Given the available literature on measured radiation exposure to the interventionist, and the controversy regarding dose thresholds, it is our current recommendation that the interventional pain physician use shielded eyewear. As the breadth of interventional procedures continues to grow, so does the radiation risk to the interventional pain physician. In this paper, we attempt to outline the risk of cataract formation in the scope of practice of an interventional pain physician and describe techniques that may help reduce them.

  3. Non-ionising radiation human exposure assessment near telecommunication devices in Croatia.

    Science.gov (United States)

    Simunić, Dina

    2006-03-01

    This paper gives an overview of the regulatory acts in non-ionising radiation in the world, with a special emphasis on basic guidelines issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). ICNIRP Guidelines are implemented in many countries worldwide. Croatia has also implemented them indirectly through the European Recommendation 1999/519/EC. The Croatian regulatory acts include the Non-lonising Radiation Protection Act, Ordinance on Electromagnetic Fields (EMF) Protection, and the Ordinance on Basic Requirements for Devices which produce Optical Radiation and Measures for Optical Radiation Protection. Dosimetry and densitometry are compliant with relevant international and European standards. The paper presents an example of densitometric human exposure assessment in complex indoor exposure conditions. In spite of a high number of indoor and outdoor sources and the "worst-case exposure assessment", the results are within the limits defined by the Croatian EMF Ordinance.

  4. Occupational radiation exposure and mortality: second analysis of the National Registry for Radiation Workers

    Energy Technology Data Exchange (ETDEWEB)

    Muirhead, C.R.; Goodill, A.A.; Haylock, R.G.E.; Vokes, J.; Little, M.P.; Jackson, D.A.; O' Hagan, J.A.; Thomas, J.M.; Kendall, G.M.; Silk, T.J.; Bingham, D.; Berridge, G.L.C. [National Radiological Protection Board, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom)

    1999-03-01

    less than zero. For multiple myeloma there was an indication of an increasing trend in risk with external dose (p = 0.06), although the evidence for this trend disappeared after omitting workers monitored for exposure to internal emitters. The second NRRW analysis provides stronger inferences than the first on occupational radiation exposure and cancer mortality; the 90% confidence intervals for the risk per unit dose are tighter than before, and now exclude values which are greater than four times those seen among the Japanese A-bomb survivors, although they are also generally consistent with an observation of no raised risk. Furthermore, there is evidence, of borderline statistical significance, of an increasing risk for leukaemia excluding CLL, and, as with solid cancers, the data are consistent with the A-bomb findings. (author)

  5. Radiation exposure of eyes, thyroid gland and hands in orthopaedic staff: a systematic review

    Directory of Open Access Journals (Sweden)

    Kesavachandran Chandrasekharan Nair

    2012-10-01

    Full Text Available Abstract Background Various procedures, especially minimal invasive techniques using fluoroscopy, pose a risk of radiation exposure to orthopaedic staff. Anatomical sites such as the eyes, thyroid glands and hands are more vulnerable to radiation considering the limited use of personal protective devices in the workplace. The objective of the study is to assess the annual mean cumulative and per procedure radiation dose received at anatomical locations like eyes, thyroid glands and hands in orthopaedic staff using systematic review. Methods The review of literature was conducted using systematic search of the database sources like PUBMED and EMBASE using appropriate keywords. The eligibility criteria and the data extraction of literature were based on study design (cohort or cross-sectional study, study population (orthopaedic surgeons or their assistants, exposure (doses of workplace radiation exposure at hands/fingers, eye/forehead, neck/thyroid, language (German and English. The literature search was conducted using a PRISMA checklist and flow chart. Results Forty-two articles were found eligible and included for the review. The results show that radiation doses for the anatomical locations of eye, thyroid gland and hands were lower than the dose levels recommended. But there is a considerable variation of radiation dose received at all three anatomical locations mainly due to different situations including procedures (open and minimally invasive, work experience (junior and senior surgeons,distance from the primary and secondary radiation, and use of personal protective equipments (PPEs. The surgeons receive higher radiation dose during minimally invasive procedures compared to open procedures. Junior surgeons are at higher risk of radiation exposure compared to seniors. PPEs play a significant role in reduction of radiation dose. Conclusions Although the current radiation precautions appear to be adequate based on the low dose radiation

  6. Radiation exposures of workers and the public associated with the transport of radioactive material in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Schwarz, G.; Fett, H.J.; Lange, F. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Cologne (Germany)

    2004-07-01

    Most radioactive material packages transported emit penetrating ionising radiation and radiation exposures of transport workers and the public may occur during their transport. The radiation exposures incurred by transport workers and members of the public can vary significantly depending on a number of factors: most important is the type of radiation emitted (primarily gamma and neutron radiation), the radiation field intensity in the surrounding of a package and conveyance and the duration of exposure to ionising radiation. The information and guidance material on occupational exposures has primarily been derived from a survey and analysis of personal monitoring data provided by a number of commercial transport operators in Germany known as major carrier and handler organisations of fuel cycle and non-fuel cycle material (in terms of the number of pack-ages and the activity carriaged). To some extent advantage was taken of compilations of statistical transport and exposure data collated within other transport safety analysis studies including research projects funded by the European Commission. The exposure data collected cover the time period of the last 4 - 8 years and are most representative for routine transport operations closely related to the movement phase of packaged radioactive material, i.e. receipt, vehicle loading, carriage, in-transit storage, intra-/intermodal transfer, vehicle unloading and delivery at the final destination of loads of radioactive material and packages and the related supervisory and health physics functions. Radiation dose monitoring of members of the public, however, is generally impracticable and, consequently, the information available relies on employing dose assessment models and reflects radiation exposures incurred by hypothetical or critical group individuals of members of the public under normal conditions of transport.

  7. The assessment of electromagnetic field radiation exposure for mobile phone users

    OpenAIRE

    Buckus Raimondas; Strukcinskiene Birute; Raistenskis Juozas

    2014-01-01

    Background/Aim. During recent years, the widespread use of mobile phones has resulted in increased human exposure to electromagnetic field radiation and to health risks. Increased usage of mobile phones at the close proximity raises questions and doubts in safety of mobile phone users. The aim of the study was to assess an electromagnetic field radiation exposure for mobile phone users by measuring electromagnetic field strength in different settings at the...

  8. Assessment of radiation exposure of nuclear medicine staff using personal TLD dosimeters and charcoal detectors

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, F.; Garcia-Talavera, M.; Pardo, R.; Deban, L. [Valladolid Univ., Dept. de Quimica Analitica, Facultad de Ciencias (Spain); Garcia-Talavera, P.; Singi, G.M.; Martin, E. [Hospital Clinico Univ., Servicio de Medicina Nuclear, Salamanca (Spain)

    2006-07-01

    Although the main concern regarding exposure to ionizing radiation for nuclear medicine workers is external radiation, inhalation of radionuclides can significantly contribute to the imparted doses. We propose a new approach to assess exposure to inhalation of {sup 131}I based on passive monitoring using activated charcoal detectors. We compared the inhalation doses to the staff of a nuclear medicine department, based on the measurements derived from charcoal detectors placed at various locations, and the external doses monitored using personal TLD dosimeters. (authors)

  9. Auditory brainstem response changes during exposure to GSM-900 radiation: an experimental study.

    Science.gov (United States)

    Kaprana, Antigoni E; Chimona, Theognosia S; Papadakis, Chariton E; Velegrakis, Stylianos G; Vardiambasis, Ioannis O; Adamidis, Georgios; Velegrakis, George A

    2011-01-01

    The objective of the present study was to investigate the possible electrophysiological time-related changes in auditory pathway during mobile phone electromagnetic field exposure. Thirty healthy rabbits were enrolled in an experimental study of exposure to GSM-900 radiation for 60 min and auditory brainstem responses (ABRs) were recorded at regular time-intervals during exposure. The study subjects were radiated via an adjustable power and frequency radio transmitter for GSM-900 mobile phone emission simulation, designed and manufactured according to the needs of the experiment. The mean absolute latency of waves III-V showed a statistically significant delay (p < 0.05) after 60, 45 and 15 min of exposure to electromagnetic radiation of 900 MHz, respectively. Interwave latency I-III was found to be prolonged after 60 min of radiation exposure in correspondence to wave III absolute latency delay. Interwave latencies I-V and III-V were found with a statistically significant delay (p < 0.05) after 30 min of radiation. No statistically significant delay was found for the same ABR parameters in recordings from the ear contralateral to the radiation source at 60 min radiation exposure compared with baseline ABR. The ABR measurements returned to baseline recordings 24 h after the exposure to electromagnetic radiation of 900 MHz. The prolongation of interval latencies I-V and III-V indicates that exposure to electromagnetic fields emitted by mobile phone can affect the normal electrophysiological activity of the auditory system, and these findings fit the pattern of general responses to a stressor.

  10. Rays Sting: The Acute Cellular Effects of Ionizing Radiation Exposure.

    Science.gov (United States)

    Franco, A; Ciccarelli, M; Sorriento, D; Napolitano, L; Fiordelisi, A; Trimarco, B; Durante, M; Iaccarino, G

    2016-05-01

    High-precision radiation therapy is a clinical approach that uses the targeted delivery of ionizing radiation, and the subsequent formation of reactive oxygen species (ROS) in high proliferative, radiation sensitive cancers. In particular, in thoracic cancer ratdiation treatments, can not avoid a certain amount of cardiac toxicity. Given the low proliferative rate of cardiac myocytes, research has looked at the effect of radiation on endothelial cells and consequent coronary heart disease as the mechanism of ratdiation induced cardiotoxicity. In fact, little is known concerning the direct effect of radiation on mitochondria dynamis in cardiomyocyte. The main effect of ionizing radiation is the production of ROS and recent works have uncovered that they directly participates to pivotal cell function like mitochondrial quality control. In particular ROS seems to act as check point within the cell to promote either mitochondrial biogenesis and survival or mitochondrial damage and apoptosis. Thus, it appears evident that the functional state of the cell, as well as the expression patterns of molecules involved in mitochondrial metabolism may differently modulate mitochondrial fate in response to radiation induced ROS responses. Different molecules have been described to localize to mitochondria and regulate ROS production in response to stress, in particular GRK2. In this review we will discuss the evidences on the cardiac toxicity induced by X ray radiation on cardiomyocytes with emphasis on the role played by mitochondria dynamism.

  11. DNA repair and cell cycle biomarkers of radiation exposure and inflammation stress in human blood.

    Directory of Open Access Journals (Sweden)

    Helen Budworth

    Full Text Available DNA damage and repair are hallmarks of cellular responses to ionizing radiation. We hypothesized that monitoring the expression of DNA repair-associated genes would enhance the detection of individuals exposed to radiation versus other forms of physiological stress. We employed the human blood ex vivo radiation model to investigate the expression responses of DNA repair genes in repeated blood samples from healthy, non-smoking men and women exposed to 2 Gy of X-rays in the context of inflammation stress mimicked by the bacterial endotoxin lipopolysaccharide (LPS. Radiation exposure significantly modulated the transcript expression of 12 genes of 40 tested (2.2E-06radiation. Three genes of this panel (CDKN1A, FDXR and BBC3 were also highly sensitive to LPS treatment in the absence of radiation exposure, and LPS co-treatment significantly affected their radiation responses. At the protein level, BAX and pCHK2-thr68 were elevated after radiation exposure, but the pCHK2-thr68 response was significantly decreased in the presence of LPS. Our combined panel yields an estimated 4-group accuracy of ∼90% to discriminate between radiation alone, inflammation alone, or combined exposures. Our findings suggest that DNA repair gene expression may be helpful to identify biodosimeters of exposure to radiation, especially within high-complexity exposure scenarios.

  12. Spatial Positioning of RET and H4 Following Radiation Exposure Leads to Tumor Development

    Directory of Open Access Journals (Sweden)

    Yuri E. Nikiforov

    2001-01-01

    Full Text Available Exposure to ionizing radiation is a well-known risk factor for a number of human cancers, including leukemia, thyroid cancer, soft tissue sarcomas, and many others. Although it has been known for a long time that radiation exposure to the cell results in extensive DNA damage, including double strand DNA breaks, the exact mechanisms of radiation-induced carcinogenesis remain unknown. Recently, a large increase in incidence of thyroid cancer was observed in children exposed to radiation after the Chernobyl nuclear accident [1]. A high prevalence of chromosomal rearrangements involving the RET gene was found among these radiation-induced thyroid tumors [2,3]. As a result of such rearrangement, a portion of the RET gene is fused with another gene, typically with the H4 or ELE1. However, since the DNA targets of ionizing radiation are randomly distributed throughout the cell nucleus, the reason for predilection for the RET rearrangements in thyroid cells was unclear.

  13. Effective Patient Education in Medical Imaging: Public Perceptions of Radiation Exposure Risk.

    Science.gov (United States)

    Ludwig, Rebecca L.; Turner, Lori W.

    2002-01-01

    In a cross-sectional survey of 200 adults, less than half agreed with experts on the risks of radiation exposure; 75-90% thought that medical imaging providers should be highly regulated; and less than one-quarter knew that most radiation damage is not permanent. (SK)

  14. 29 CFR 570.57 - Exposure to radioactive substances and to ionizing radiations (Order 6).

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Exposure to radioactive substances and to ionizing radiations (Order 6). 570.57 Section 570.57 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR... walls of solid material and extending from floor to ceiling; (3) The term ionizing radiations shall mean...

  15. Synergistic Effects of Exposure of Surfaces of Ionic Crystals to Radiation and Water

    Energy Technology Data Exchange (ETDEWEB)

    Dickinson, J T.; Nwe, Khin H.; Hess, Wayne P.; Langford, S C.

    2003-03-15

    We present studies of the consequences of simultaneous exposure of inorganic single crystals to radiation and water. The first case consists of a biomineral, CaHPO4-2H2O (brushite), which is a wide band gap, hydrated inorganic single crystal. We examine the laser-induced ion and neutral emissions accompanying 248 nm excimer laser radiation.

  16. Is Ionizing Radiation Harmful at any Exposure? An Echo That Continues to Vibrate.

    Science.gov (United States)

    Azzam, Edouard I; Colangelo, Nicholas W; Domogauer, Jason D; Sharma, Neha; de Toledo, Sonia M

    2016-03-01

    The health risks to humans and non-human biota exposed to low dose ionizing radiation remain ambiguous and are the subject of intense debate. The need to establish risk assessment standards based on the mechanisms underlying low-level radiation exposure has been recognized by regulatory agencies as critical to adequately protect people and to make the most effective use of national resources. Here, the authors briefly review evidence showing that the molecular and biochemical changes induced by low doses of radiation differ from those induced by high doses. In particular, an array of redundant and inter-related mechanisms act in both prokaryotes and eukaryotes to restore DNA integrity following exposures to relatively low doses of sparsely ionizing radiation. Furthermore, the radiation-induced protective mechanisms often overcompensate and minimize the mutagenic potential of the byproducts of normal oxidative metabolism. In contrast to adaptive protection observed at low doses of sparsely ionizing radiation, there is evidence that even a single nuclear traversal by a densely ionizing particle track can trigger harmful effects that spread beyond the traversed cell and induce damaging effects in the nearby bystander cells. In vivo studies examining whether exposure to low dose radiation at younger age modulates the latency of expression of age-related diseases such as cancer, together with studies on the role of genetic susceptibility, will further illuminate the magnitude of risk of exposure to low dose radiation.

  17. Anatomical exposure patterns of skin to sunlight: relative contributions of direct, diffuse and reflected ultraviolet radiation.

    Science.gov (United States)

    Vernez, D; Milon, A; Vuilleumier, L; Bulliard, J-L

    2012-08-01

    The dose-response between ultraviolet (UV) exposure patterns and skin cancer occurrence is not fully understood. Sun-protection messages often focus on acute exposure, implicitly assuming that direct UV radiation is the key contributor to the overall UV exposure. However, little is known about the relative contribution of the direct, diffuse and reflected radiation components. To investigate solar UV exposure patterns at different body sites with respect to the relative contribution of the direct, diffuse and reflected radiation. A three-dimensional numerical model was used to assess exposure doses for various body parts and exposure scenarios of a standing individual (static and dynamic postures). The model was fed with erythemally weighted ground irradiance data for the year 2009 in Payerne, Switzerland. A year-round daily exposure (08:00-17:00 h) without protection was assumed. For most anatomical sites, mean daily doses were high (typically 6.2-14.6 standard erythemal doses) and exceeded the recommended exposure values. Direct exposure was important during specific periods (e.g. midday during summer), but contributed moderately to the annual dose, ranging from 15% to 24% for vertical and horizontal body parts, respectively. Diffuse irradiation explained about 80% of the cumulative annual exposure dose. Acute diffuse exposures were also observed during cloudy summer days. The importance of diffuse UV radiation should not be underestimated when advocating preventive measures. Messages focused on avoiding acute direct exposures may be of limited efficiency to prevent skin cancers associated with chronic exposure. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

  18. 47 CFR 1.1310 - Radiofrequency radiation exposure limits.

    Science.gov (United States)

    2010-10-01

    ... Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz,” ANSI... Criteria for Radiofrequency Electromagnetic Fields,” NCRP Report No. 86, Sections 17.4.1, 17.4.1.1, 17.4.2... 1500 MHz, exposure limits for field strength and power density are also generally based on...

  19. Determinants of personal ultraviolet-radiation exposure doses on a sun holiday

    DEFF Research Database (Denmark)

    Petersen, B; Thieden, E; Philipsen, P A

    2013-01-01

    A great number of journeys to sunny destinations are sold to the Danish population every year. We suspect that this travel considerably increases personal annual ultraviolet-radiation (UVR) exposure doses. This is important because such exposure is the main cause of skin cancer, and studies have ...

  20. 38 CFR 3.311 - Claims based on exposure to ionizing radiation.

    Science.gov (United States)

    2010-07-01

    ... radiation and shall include the following: (i) All forms of leukemia except chronic lymphatic (lymphocytic) leukemia; (ii) Thyroid cancer; (iii) Breast cancer; (iv) Lung cancer; (v) Bone cancer; (vi) Liver cancer... years after exposure; (ii) Leukemia may become manifest at any time after exposure; (iii) Posterior...

  1. Acute effects of solar particle event radiation

    Science.gov (United States)

    Kennedy, Ann R.; Weissman, Drew; Sanzari, Jenine K.; Krigsfeld, Gabriel S.; Wan, X. Steven; Romero-Weaver, Ana L.; Diffenderfer, Eric S.; Lin, L.; Cengel, K.

    2014-01-01

    simulated microgravity (hindlimb suspension), leads to a very high level of morbidity/mortality in mice given a bacterial challenge with non-toxic levels of Pseudomonas aeruginosa or Klebsiella pneumoniae; the threshold for this effect was 1.5 Gy. (v) T-cell activation was reduced in mice exposed to SPE-like radiation with or without simulated hypogravity (either partial weight suspension or hindlimb suspension) (e.g. [4]). (vi) Radiation and simulated hypogravity had synergistic effects on immune system biological endpoints (e.g. [5]). (vii) Pigs exposed to simulated SPE radiation exhibited increases in intracranial pressure that remained elevated over the 90-day experimental period. (viii) A major sparing effect of SPE-like low dose rate radiation (compared with the results for high dose rate radiation) was observed for ferret emesis parameters, such that the differences between the results for ferret exposure to low dose rate radiation (50 cGy/h) and controls were not statistically significant (for doses up to 2 Gy). For high dose rate SPE proton radiation, the threshold value for retching was 75 cGy, and for ferret vomiting, it was 1 Gy.

  2. Exposure of luminous marine bacteria to low-dose gamma-radiation.

    Science.gov (United States)

    Kudryasheva, N S; Petrova, A S; Dementyev, D V; Bondar, A A

    2017-04-01

    The study addresses biological effects of low-dose gamma-radiation. Radioactive (137)Cs-containing particles were used as model sources of gamma-radiation. Luminous marine bacterium Photobacterium phosphoreum was used as a bioassay with the bioluminescent intensity as the physiological parameter tested. To investigate the sensitivity of the bacteria to the low-dose gamma-radiation exposure (≤250 mGy), the irradiation conditions were varied as follows: bioluminescence intensity was measured at 5, 10, and 20°С for 175, 100, and 47 h, respectively, at different dose rates (up to 4100 μGy/h). There was no noticeable effect of gamma-radiation at 5 and 10°С, while the 20°С exposure revealed authentic bioluminescence inhibition. The 20°С results of gamma-radiation exposure were compared to those for low-dose alpha- and beta-radiation exposures studied previously under comparable experimental conditions. In contrast to ionizing radiation of alpha and beta types, gamma-emission did not initiate bacterial bioluminescence activation (adaptive response). As with alpha- and beta-radiation, gamma-emission did not demonstrate monotonic dose-effect dependencies; the bioluminescence inhibition efficiency was found to be related to the exposure time, while no dose rate dependence was found. The sequence analysis of 16S ribosomal RNA gene did not reveal a mutagenic effect of low-dose gamma radiation. The exposure time that caused 50% bioluminescence inhibition was suggested as a test parameter for radiotoxicity evaluation under conditions of chronic low-dose gamma irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Cognitive evoked potentials P300 after radiation exposure.

    Science.gov (United States)

    Loganovsky, K M; Kuts, K V

    2016-12-01

    The study was aimed at evaluating features of brain information processes and cognitive functioning in the remote period after irradiation due to the Chornobyl accident by using cognitive evoked potentials P300. The study included 128 people, 112 male Chornobyl clean up workers in 1986-1987 with the records of radiation doses available in Clinical and Epidemiological Registry (CER) of State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine» (NRCRM) (study group) and 16 unexposed persons due to the Chornobyl disaster (control group). At the time of the survey the average age of clean up workers (M ± SD) was (57.3 ± 5.9) years, range 44-65 years, and of unex posed persons was (57.3 ± 6.5) years, range 44-65 years. Radiation doses were within the range 0.0002-1.23 Gy, with the arithmetic mean dose (M ± SD) of (0.2 ± 0.2) Gy and the geometric mean dose of 0.1 Gy. The radiocerebral effect in the projection of the left posterior superior temporal gyrus (Wernicke's area) proportionally to the radiation dose with the possible threshold of 0.05 Gy of total irradiation was revealed, with increasing radiation dose cognitive component P300 amplitude reduces and its latency period (LP) increases, espe cially at doses > 0.3-0.5 Gy. At doses > 0.5 Gy the functional relationship with the radiation dose for LP P300 increase in the projection of Wernicke's area (r = 0.9; p = 0.027) has been found. The neurophysiological features detected are fully consistent with hypotheses both on radiosensitiv ity of human central nervous system and accelerated aging of the brain under the influence of small doses of ioniz ing radiation, and have questioned the feasibility of long term manned space flights (including Mars) until the development of adequate radiation hygiene standardization for space crews and invention of means for radiation protection of space flights. Further dynamic clinical and neurophysiological

  4. Analysis of Radiation Exposure for Naval Personnel at Operation SANDSTONE.

    Science.gov (United States)

    1983-08-15

    Operation SANDSTONE Dose Reconstruction Methodology I I 2-1 Enewetak Atoll Anchorage Areas 14 2-2 Destroyer Patrol Sector Chart for Operation SANDSTONE 18...2-3 Average Free-Field Radiation Intensity for Southern and Northern Anchorage Areas - Enewetak Atoll 24 2-4 Average Free-Field Radiation Intensity...Operation SANDSTONE was the second nuclear test series held in the Marshall 0 Islands. It consisted of three nuclear weapon tests at Enewetak * Atoll in

  5. Ionizing radiation exposure among kidney transplant recipients due to medical imaging during the pretransplant evaluation.

    Science.gov (United States)

    Nguyen, Kim N; Patel, Anup M; Weng, Francis L

    2013-05-01

    Kidney transplant recipients are at increased risk for malignancies. One recognized risk for malignancy is ionizing radiation. The purpose of this study was to determine, among kidney transplant recipients, the medical imaging procedures that contribute to radiation exposure and their cumulative radiation exposure, as a result of their pretransplant evaluation. Medical records of patients who received a first, kidney-alone transplant during 2008 at a single transplant center were examined. This study identified medical imaging procedures that were performed as prerequisites for deceased donor wait-listing or receipt of live donor kidney transplants and to maintain active status on the wait list. Frequencies of medical imaging procedures and cumulative effective doses of radiation were calculated. Among the 172 kidney transplant recipients, 905 procedures were performed. Seventy patients (40.7%) were exposed to low dose (0-20 mSv), 51 (29.7%) were exposed to moderate dose (>20-50 mSv), 28 (16.3%) were exposed to high dose (>50-100 mSv), and 23 (13.4%) were exposed to very high dose (>100 mSv) cumulative effective radiation. Nuclear stress tests accounted for 82.9% of the total radiation exposure. In multivariate analysis, older age, diabetes, and black race were associated with exposure to >20 mSv radiation during the pretransplant evaluation. Kidney transplant recipients are exposed to large amounts of ionizing radiation from medical imaging during the pretransplant evaluation. The effects of radiation upon malignancy risk and strategies to reduce this radiation exposure warrant further investigation.

  6. A novel dosimeter for measuring the amount of radiation exposure of surgeons during percutaneous nephrolithotomy: Instadose™

    Science.gov (United States)

    Yuruk, Emrah; Gureser, Gokhan; Tuken, Murat; Ertas, Kasim

    2016-01-01

    Introduction The aim of this study was to demonstrate the efficacy of Instadose™, a novel dosimeter designed for radiation workers to provide a measurement of the radiation dose at any time from any computer; to determine the amount of radiation exposure during percutaneous nephrolithotomy (PNL); and to evaluate the factors that affect the amount of radiation exposed. Material and methods Two experienced surgeons wore Instadose™ on the outer part of their lead aprons during the PNL procedures performed between December 2013 and July 2014. Patient demographics and stone characteristics were noted. Factors affecting radiation dose were determined. Fluoroscopic screening time was compared with the amount of radiation in order to validate the measurements of Instadose™. Results Overall, 51 patients with a mean age of 43.41 ±18.58 (range 1–75) years were enrolled. Male to female ratio was 35/16. The amount of radiation was greater than 0.01mSv in only 19 (37.25%) cases. Stone location complexity (p = 0.380), dilation type (p = 0.584), stone size (p = 0.565), dilation size (p = 0.891) and access number (p = 0.268) were not associated with increased radiation exposure. Instadose™ measurements were correlated with fluoroscopic screening time (r = 0.519, p = 0.001). Conclusions Instadose™ is a useful tool for the measurement of radiation exposure during PNL. The advantage of measuring the amount of radiation exposure after each PNL operation is that it may aid urologists in taking appropriate precautions to minimize the risk of radiation related complications. PMID:27551558

  7. QUALITY OF RADIOGRAPHIC IMAGES: LABORATORY EVALUATION OF INTRAORAL FILMS, FILTERS, COLLIMATORS, AND RADIATION EXPOSURE

    Directory of Open Access Journals (Sweden)

    TAMBURUS José Roberto

    1997-01-01

    Full Text Available In order to evaluate density, radiographic contrast and dose of radiation exposure, the author analyzed 80 radiographs containing 640 optical density data of the images of a penetrometer, exposed to the radiation beam with combinations between D and E periapical films, aluminum and copper/aluminum filters, and circular or rectangular collimators. The data obtained were analyzed by ANOVA and allowed the following conclusions: 1 aluminum filtration resulted in improved image contrast; 2 the use of group D film and an aluminum filter produced improved image contrast quality; 3 the rectangular collimator contributed to the production of improved contrast and to the reduction of radiation exposure, but did not affect density; 4 the combination of copper/aluminum filter, E group film and rectangular collimation significantly reduced radiation exposure.

  8. Annealing behavior of radiation damage in JFET-input operational amplifiers

    Institute of Scientific and Technical Information of China (English)

    Zheng Yuzhan; Lu Wu; Ren Diyuan; Wang Yiyuan; Guo Qi; Yu Xuefeng

    2009-01-01

    The elevated and room temperature annealing behavior of radiation damage in JFET-input operational amplifiers (op-amps) were investigated. High-and low-dose-rate irradiation results show that one of the JFET-input op-amps studied in this paper exhibits enhanced low-dose-rate sensitivity and the other shows time-dependent effect. The offset voltage of both op-amps increases during long-term annealing at room temperature. However, the offset voltage decreases at elevated temperature. The dramatic difference in annealing behavior at room and elevated temperatures indicates the migration behavior of radiation-induced species at elevated and room temperatures. This provides useful information to understand the degradation and annealing mechanisms in JFET-input op-amps under total ionizing radiation. Moreover, the annealing of oxide trapped charges should be taken into consideration, when using elevated temperature methods to evaluate low-dose-rate damage.

  9. External radiation dose and cancer mortality among French nuclear workers. Considering potential confounding by internal radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, L.; Laurent, O.; Samson, E.; Caer-Lorho, S.; Laurier, D.; Leuraud, K. [Institute for Radiological Protection and Nuclear Safety, Fontenay aux Roses (France). Ionizing Radiation Epidemiology Lab.; Laroche, P. [AREVA, Paris (France); Le Guen, B. [EDF, Saint Denis (France)

    2016-11-15

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat a l'Energie Atomique), AREVA NC, or EDF (Electricite de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  10. External radiation dose and cancer mortality among French nuclear workers: considering potential confounding by internal radiation exposure.

    Science.gov (United States)

    Fournier, L; Laurent, O; Samson, E; Caër-Lorho, S; Laroche, P; Le Guen, B; Laurier, D; Leuraud, K

    2016-11-01

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat à l'Energie Atomique), AREVA NC, or EDF (Electricité de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  11. Reduction of radiation exposure in catheter ablation of atrial fibrillation: Lesson learned

    Institute of Scientific and Technical Information of China (English)

    Roberto; De; Ponti

    2015-01-01

    Over the last decades, the concern for the radiation injury hazard to the patients and the professional staff has increased in the medical community. Since there is no magnitude of radiation exposure that is known to be completely safe, the use of ionizing radiation during medical diagnostic or interventional procedures should be as low as reasonably achievable(ALARA principle). Nevertheless, in cardiovascular medicine, radiation exposure for coronary percutaneous interventions or catheter ablation of cardiac arrhythmias may be high: for ablation of a complex arrhythmia, such as atrial fibrillation, the mean dose can be > 15 m Sv and in some cases > 50 m Sv. In interventional electrophysiology, although fluoroscopy has been widely used since the beginning to navigate catheters in the heart and the vessels and to monitor their position, the procedure is not based on fluoroscopic imaging. Therefore, nonfluoroscopic three-dimensional systems can be used to navigate electrophysiology catheters in the heart with no or minimal use of fluoroscopy. Although zerofluoroscopy procedures are feasible in limited series, there may be difficulties in using no fluoroscopy on a routine basis. Currently, a significant reduction in radiation exposure towards near zero-fluoroscopy procedures seems a simpler task to achieve, especially in ablation of complex arrhythmias, such as atrial fibrillation. The data reported in the literature suggest the following three considerations. First, the use of the non-fluoroscopic systems is associated with a consistent reduction in radiation exposure in multiple centers: the more sophisticated and reliable this technology is, the higher the reduction in radiation exposure. Second, the use of these systems does not automatically lead to reduction of radiation exposure, but an optimized workflow should be developed and adopted for a safe non-fluoroscopic navigation of catheters. Third, at any level of expertise, there is a specific learning curve for

  12. Operator radiation exposure during transradial coronary angiography : Effect of single vs. double catheters.

    Science.gov (United States)

    Tarighatnia, A; Pourafkari, L; Farajollahi, A; Mohammadalian, A H; Ghojazadeh, M; Nader, N D

    2017-07-17

    The right radial artery has gained popularity as the preferred access site for coronary angiography. To save time and limit the radiation exposure of operators and patients, newly designed catheters can be used to access both the right and left coronary arteries. The aim of this study was to compare operator radiation exposure between single-catheter (SCA) and two-catheter approaches (TCA). In all, 256 patients undergoing diagnostic coronary angiography via the right radial artery in a high-volume medical center were randomized to either the SCA or TCA group. The dose of radiation exposure of the operators was measured by an electronic dosimeter attached to the breast pocket of the operator's apron. The dose-area product and air kerma were used as indices of patient exposure to radiation. The duration of fluoroscopy "beam-on" time, acquisition time, and total duration of the procedure were measured and analyzed for the two groups. Operator radiation exposure was 21.6 ± 11.4 µSv in the SCA group, which was significantly less than 28.0 ± 14.9 µSv in the TCA group. The duration of fluoroscopy was significantly shorter in the SCA group than in the TCA group (152 ± 83 vs. 203 ± 121 s; p exposure of operators to radiation. The shorter duration of fluoroscopy beam-on time and total procedure time may contribute to the lower exposure of operators to radiation.

  13. Initiation-promotion model of tumor prevalence in mice from space radiation exposures.

    Science.gov (United States)

    Cucinotta, F A; Wilson, J W

    1995-08-01

    Exposures in space consist of low-level background components from galactic cosmic rays (GCR), occasional intense-energetic solar-particle events, periodic passes through geomagnetic-trapped radiation, and exposure from possible onboard nuclear-propulsion engines. Risk models for astronaut exposure from such diverse components and modalities must be developed to assure adequate protection in future NASA missions. The low-level background exposures (GCR), including relativistic heavy ions (HZE), will be the ultimate limiting factor for astronaut career exposure. We consider herein a two-mutation, initiation-promotion, radiation-carcinogenesis model in mice in which the initiation stage is represented by a linear kinetics model of cellular repair/misrepair, including the track-structure model for heavy ion action cross-sections. The model is validated by comparison with the harderian gland tumor experiments of Alpen et al. for various ion beams. We apply the initiation-promotion model to exposures from galactic cosmic rays, using models of the cosmic-ray environment and heavy ion transport, and consider the effects of the age of the mice prior to and after the exposure and of the length of time in space on predictions of relative risk. Our results indicate that biophysical models of age-dependent radiation hazard will provide a better understanding of GCR risk than models that rely strictly on estimates of the initial slopes of these radiations.

  14. Inferring ultraviolet anatomical exposure patterns while distinguishing the relative contribution of radiation components

    Energy Technology Data Exchange (ETDEWEB)

    Vuilleumier, Laurent [Federal Office of Meteorology and Climatology, MeteoSwiss, Payerne (Switzerland); Milon, Antoine; Vernez, David [Institute of Work and Health, University of Lausanne and Geneva, Lausanne (Switzerland); Bulliard, Jean-Luc [Cancer Epidemiology Unit, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne (Switzerland); Moccozet, Laurent [Institute of Services Science, University of Geneva (Switzerland)

    2013-05-10

    Exposure to solar ultraviolet (UV) radiation is the main causative factor for skin cancer. UV exposure depends on environmental and individual factors, but individual exposure data remain scarce. While ground UV irradiance is monitored via different techniques, it is difficult to translate such observations into human UV exposure or dose because of confounding factors. A multi-disciplinary collaboration developed a model predicting the dose and distribution of UV exposure on the basis of ground irradiation and morphological data. Standard 3D computer graphics techniques were adapted to develop a simulation tool that estimates solar exposure of a virtual manikin depicted as a triangle mesh surface. The amount of solar energy received by various body locations is computed for direct, diffuse and reflected radiation separately. Dosimetric measurements obtained in field conditions were used to assess the model performance. The model predicted exposure to solar UV adequately with a symmetric mean absolute percentage error of 13% and half of the predictions within 17% range of the measurements. Using this tool, solar UV exposure patterns were investigated with respect to the relative contribution of the direct, diffuse and reflected radiation. Exposure doses for various body parts and exposure scenarios of a standing individual were assessed using erythemally-weighted UV ground irradiance data measured in 2009 at Payerne, Switzerland as input. For most anatomical sites, mean daily doses were high (typically 6.2-14.6 Standard Erythemal Dose, SED) and exceeded recommended exposure values. Direct exposure was important during specific periods (e.g. midday during summer), but contributed moderately to the annual dose, ranging from 15 to 24% for vertical and horizontal body parts, respectively. Diffuse irradiation explained about 80% of the cumulative annual exposure dose.

  15. Analysis of university student awareness of radiation exposures from consumer products

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Hwan [Korean Advance Institute of Science and Technology, Daejeon (Korea, Republic of); Cho, Kun Woo [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-05-15

    Since the terminology 'radioactive consumer product' is not quite familiar to the public and is often considered as negative and detrimental things, the educational curriculum is essential for establishing reliability of nuclear energy related and for the development of better communication strategy of radiation risk with the public. To provide base data which is valuable for establishing efficient curriculum of education and training about radiation safety, it is necessary to apprehend the different level of awareness of radiation exposures classified by various consumer products. On November 2014, a question investigation about asking awareness level of radiation exposure from various consumer products was done for university students who are highly educated. The object students are studied at a four-year-course universities which is located at Daejeon City. Although the average awareness level is comparatively low, the awareness of senior students, who major in radiation, nuclear related departments and male students are relatively high. On the other hand, the awareness of freshman, sophomore, junior students, who do not major in radiation, nuclear related departments and female students are relatively low. It is necessary to provide various information to avoid unnecessary concerns and misconceptions about radiation exposure. This paper will be an instrument for efficient establishment of curriculum of education and training related with radiation safety.

  16. Detection of DNA Damage by Space Radiation in Human Fibroblasts Flown on the International Space Station

    Science.gov (United States)

    Lu, Tao; Zhang, Ye; Wong, Michael; Feiveson, Alan; Gaza, Ramona; Stoffle, Nicholas; Wang, Huichen; Wilson, Bobby; Rohde, Larry; Stodieck, Louis; hide

    2017-01-01

    Space radiation consists of energetic charged particles of varying charges and energies. Exposure of astronauts to space radiation on future long duration missions to Mars, or missions back to the Moon, is expected to result in deleterious consequences such as cancer and comprised central nervous system (CNS) functions. Space radiation can also cause mutation in microorganisms, and potentially influence the evolution of life in space. Measurement of the space radiation environment has been conducted since the very beginning of the space program. Compared to the quantification of the space radiation environment using physical detectors, reports on the direct measurement of biological consequences of space radiation exposure have been limited, due primarily to the low dose and low dose rate nature of the environment. Most of the biological assays fail to detect the radiation effects at acute doses that are lower than 5 centiSieverts. In a recent study, we flew cultured confluent human fibroblasts in mostly G1 phase of the cell cycle to the International Space Station (ISS). The cells were fixed in space after arriving on the ISS for 3 and 14 days, respectively. The fixed cells were later returned to the ground and subsequently stained with the gamma-H2AX (Histone family, member X) antibody that are commonly used as a marker for DNA damage, particularly DNA double strand breaks, induced by both low-and high-linear energy transfer radiation. In our present study, the gamma-H2AX (Histone family, member X) foci were captured with a laser confocal microscope. To confirm that some large track-like foci were from space radiation exposure, we also exposed, on the ground, the same type of cells to both low-and high-linear energy transfer protons, and high-linear energy transfer Fe ions. In addition, we exposed the cells to low dose rate gamma rays, in order to rule out the possibility that the large track-like foci can be induced by chronic low-linear energy transfer

  17. External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

    Energy Technology Data Exchange (ETDEWEB)

    Abo-Elmagd, M. [National Institute for Standard, Radiation Measurements Department, P.O. Box 136 Giza code no. 12211 (Egypt)]. E-mail: abo_elmgd@hotmail.com; Metwally, S.M. [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); Elmongy, S.A. [Atomic Energy Authority, Nuclear Safety, Cairo (Egypt); Salama, E. [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); El-Fiki, S.A. [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt)

    2006-02-15

    Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43{mu}Sv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively.

  18. Full Mission Astronaut Radiation Exposure Assessments for Long Duration Lunar Surface Missions

    Science.gov (United States)

    Adamczyk, Anne; Clowdsley, Martha; Qualls, Garry; Blattnig, Steve; Lee, Kerry; Fry, Dan; Stoffle, Nicholas; Simonsen, Lisa; Slaba, Tony; Walker, Steven; Zapp, Edward

    2011-01-01

    Risk to astronauts due to ionizing radiation exposure is a primary concern for missions beyond Low Earth Orbit (LEO) and will drive mission architecture requirements, mission timelines, and operational practices. For short missions, radiation risk is dominated by the possibility of a large Solar Particle Event (SPE). Longer duration missions have both SPE and Galactic Cosmic Ray (GCR) risks. SPE exposure can contribute significantly toward cancer induction in combination with GCR. As mission duration increases, mitigation strategies must address the combined risks from SPE and GCR exposure. In this paper, full mission exposure assessments were performed for the proposed long duration lunar surface mission scenarios. In order to accomplish these assessments, previously developed radiation shielding models for a proposed lunar habitat and rover were utilized. End-to-End mission exposure assessments were performed by first calculating exposure rates for locations in the habitat, rover, and during Extra-Vehicular Activities (EVA). Subsequently, total mission exposures were evaluated for the proposed timelines. Mission exposure results, assessed in terms of effective dose, are presented for the proposed timelines and recommendations are made for improved astronaut shielding and safer operational practices.

  19. Natural Sources of Radiation Exposure and the Teaching of Radioecology

    Science.gov (United States)

    Anjos, R. M.; Veiga, R.; Carvalho, C.; Sanches, N.; Estellita, L.; Zanuto, P.; Queiroz, E.; Macario, K.

    2008-01-01

    We have developed an experimental activity that introduces concepts of the natural ionizing radiation and its interaction with our contemporary environment that can be used with students from secondary to college level. The experiment is based on the use of traditional and cheap portable Geiger-Muller detectors as survey meters for "in situ"…

  20. Operator radiation exposure in cone-beam computed tomography guidance

    NARCIS (Netherlands)

    Braak, S.J.; Strijen Van, M. J L; Meijer, E.; Heesewijk Van, J. P M; Mali, W. P T M

    2016-01-01

    Objectives: Quantitative analysis of operator dose in cone-beam computed tomography guidance (CBCT-guidance) and the effect of protective shielding. Methods: Using a Rando phantom, a model was set-up to measure radiation dose for the operator hand, thyroid and gonad region. The effect of sterile rad

  1. Natural Sources of Radiation Exposure and the Teaching of Radioecology

    Science.gov (United States)

    Anjos, R. M.; Veiga, R.; Carvalho, C.; Sanches, N.; Estellita, L.; Zanuto, P.; Queiroz, E.; Macario, K.

    2008-01-01

    We have developed an experimental activity that introduces concepts of the natural ionizing radiation and its interaction with our contemporary environment that can be used with students from secondary to college level. The experiment is based on the use of traditional and cheap portable Geiger-Muller detectors as survey meters for "in situ"…

  2. Occupational exposure to radio frequency/microwave radiation and the risk of brain tumors

    DEFF Research Database (Denmark)

    Berg, Gabriele; Spallek, Jacob; Schüz, Joachim

    2006-01-01

    . "High" exposure was defined as an occupational exposure that may exceed the RF/MW-EMF exposure limits for the general public recommended by the International Commission on Non-Ionizing Radiation Protection. Multiple conditional logistic regressions were performed separately for glioma and meningioma......It is still under debate whether occupational exposure to radio frequency/microwave electromagnetic fields (RF/MW-EMF) contributes to the development of brain tumors. This analysis examined the role of occupational RF/MW-EMF exposure in the risk of glioma and meningioma. A population-based, case......-control study including 381 meningioma cases, 366 glioma cases, and 1,494 controls aged 30-69 years was performed in three German regions in 2000-2003. An exposure matrix for occupational activity was constructed by using information on RF/MW-EMF exposure collected in a computer-assisted personal interview...

  3. Non-targeted and delayed effects of exposure to ionizing radiation: II. Radiation-induced genomic instability and bystander effects in vivo, clastogenic factors and transgenerational effects

    Science.gov (United States)

    Morgan, William F.

    2003-01-01

    The goal of this review is to summarize the evidence for non-targeted and delayed effects of exposure to ionizing radiation in vivo. Currently, human health risks associated with radiation exposures are based primarily on the assumption that the detrimental effects of radiation occur in irradiated cells. Over the years a number of non-targeted effects of radiation exposure in vivo have been described that challenge this concept. These include radiation-induced genomic instability, bystander effects, clastogenic factors produced in plasma from irradiated individuals that can cause chromosomal damage when cultured with nonirradiated cells, and transgenerational effects of parental irradiation that can manifest in the progeny. These effects pose new challenges to evaluating the risk(s) associated with radiation exposure and understanding radiation-induced carcinogenesis.

  4. Thyroid Cancer Following Childhood Low-Dose Radiation Exposure: A Pooled Analysis of Nine Cohorts.

    Science.gov (United States)

    Lubin, Jay H; Adams, M Jacob; Shore, Roy; Holmberg, Erik; Schneider, Arthur B; Hawkins, Michael M; Robison, Leslie L; Inskip, Peter D; Lundell, Marie; Johansson, Robert; Kleinerman, Ruth A; de Vathaire, Florent; Damber, Lena; Sadetzki, Siegal; Tucker, Margaret; Sakata, Ritsu; Veiga, Lene H S

    2017-07-01

    The increased use of diagnostic and therapeutic procedures that involve radiation raises concerns about radiation effects, particularly in children and the radiosensitive thyroid gland. Evaluation of relative risk (RR) trends for thyroid radiation doses dose; and possible modifiers of the dose-response, e.g., sex, age at exposure, time since exposure. Pooled data from nine cohort studies of childhood external radiation exposure and thyroid cancer with individualized dose estimates, ≥1000 irradiated subjects or ≥10 thyroid cancer cases, with data limited to individuals receiving doses dose (P dose ranged from 0.0 to 0.03 Gy, with an upper 95% confidence bound of 0.04 Gy. The increasing dose-response trend persisted >45 years after exposure, was greater at younger age at exposure and younger attained age, and was similar by sex and number of treatments. Our analyses reaffirmed linearity of the dose response as the most plausible relationship for "as low as reasonably achievable" assessments for pediatric low-dose radiation-associated thyroid cancer risk.

  5. Radiation Exposure to Staff in Intensive Care Unit with Portable CT Scanner

    Directory of Open Access Journals (Sweden)

    Zhichao Xie

    2016-01-01

    Full Text Available Background. Bedside radiological procedures pose a risk of radiation exposure to ICU staff. The perception of risk may increase the degree of caution among the health care staff and raise new barriers preventing patients from obtaining prompt care. Objective. The aim of this study was to estimate the annual cumulative radiation dose to individual ICU staff. Methods. In this prospective study, forty subjects were required to wear thermoluminescent dosimeter badges during their working hours. The badges were analyzed to determine the exposure after 3 months. Results. A total of 802 radiological procedures were completed at bedside during the study period. The estimated annual dosage to doctors and nurses on average was 0.99 mSv and 0.88 mSv (p<0.001, respectively. Residents were subjected to the highest radiation exposure (1.04 mSv per year, p=0.002. The radiation dose was correlated with day shift working hours (r=0.426; p=0.006 and length of service (r=-0.403; p<0.01. Conclusions. With standard precautions, bedside radiological procedures—including portable CT scans—do not expose ICU staff to high dose of ionizing radiation. The level of radiation exposure is related to the daytime working hours and length of service.

  6. Comparison of radiation exposure during transradial diagnostic coronary angiography with single- or multi-catheters approach.

    Science.gov (United States)

    Plourde, Guillaume; Abdelaal, Eltigani; MacHaalany, Jimmy; Rimac, Goran; Poirier, Yann; Arsenault, Jean; Costerousse, Olivier; Bertrand, Olivier F

    2017-08-01

    To compare radiation exposure during transradial diagnostic coronary angiography (DCA) using standard single- or multi-catheters with different shapes. Transradial DCA can be performed using single- or multi-catheters to canulate left and right coronary ostia. To date, it remains unknown whether there are differences in radiation exposure between the two strategies. From November 2012 to June 2014, 3,410 consecutive patients who underwent transradial DCA were recruited. Groups were based on the initial diagnostic catheter used and were dichotomized between single- and multi-catheters approach. All crossovers were excluded. The multi-catheters approach (Multi) group consisted of Judkins left and right catheters, whereas the single-catheter (Single) group included Amplatz, Barbeau, or Multipurpose catheters. Fluoroscopy time (FT) as a surrogate end-point for total radiation exposure and kerma-area product (KAP; patient radiation exposure) were collected as radiation exposure parameters. A single-catheter strategy was used in 439 patients, while 2,971 patients had a multi-catheters approach. There was no significant difference in FT between groups (2.86 ± 1.48 min for Multi vs. 2.87 ± 1.72 min for Single, P = 0.13). The multi-catheters approach was associated with a significant 15% reduction in KAP (3,599 ± 2,214 cGy · cm(2) vs. 3,073 ± 1,785 cGy · cm(2) , P exposure. Whether single catheter designed for DCA by radial approach can further reduce radiation exposure compared to Judkins catheters remains to be compared in randomized studies. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Transgenerational accumulation of radiation damage in small mammals chronically exposed to Chernobyl fallout.

    Science.gov (United States)

    Ryabokon, Nadezhda I; Goncharova, R I

    2006-09-01

    The purpose of this investigation has been the analysis of the long-term development of biological damage in natural populations of a model mammalian species, the bank vole (Clethrionomys glareolus, Schreber), which were chronically exposed to low doses of ionizing radiation over 22 animal generations within 10 years following the Chernobyl accident. The time course of the biological end-points (chromosome aberrations in bone marrow cells and embryonic lethality) was compared with the time course of the whole-body absorbed dose rate from external and internal exposure in the studied populations inhabiting monitoring sites in Belarus with different ground deposition of radionuclides. The yield of chromosome aberrations and, in lesser degree, embryonic lethality was associated with the radionuclide contamination of the monitoring areas in a dose-dependent manner. As a main feature of the long-term development of biological damage under low dose rate irradiation, permanently elevated levels of chromosome aberrations and an increasing frequency of embryonic lethality have developed over 22 animal generations. This contrasts with the assumption that the biological damage would gradually disappear since in the same period of time the whole-body absorbed dose rate decreased exponentially with a half-value time of about 2.5-3 years. Furthermore, gravid females were captured, and their offspring, born and grown up under contamination-free laboratory conditions, showed the same enhanced level of chromosome aberrations. Therefore the authors suggest that, along with the biological damage attributable to the individual exposure of each animal, the observed cellular and systemic effects reflect the transgenerational transmission and accumulation, via genetic and/or epigenetic pathways, of damage attributable to the chronic low-dose rate exposure of the preceding generations of animals. They also suggest that the level of the accumulated transmissible damage in the investigated

  8. Leukemia incidence among people exposed to chronic radiation from the contaminated Techa River, 1953-2005.

    Science.gov (United States)

    Krestinina, Lyudmila; Preston, Dale L; Davis, Faith G; Epifanova, Svetlana; Ostroumova, Evgenia; Ron, Elaine; Akleyev, Alexander

    2010-05-01

    Beginning in 1950, people living on the banks of the Techa River received chronic low-dose-rate internal and external radiation exposures as a result of releases from the Mayak nuclear weapons plutonium production facility in the Southern Urals region of the Russian Federation. The Techa River cohort includes about 30,000 people who resided in riverside villages sometime between 1950 and 1960. Cumulative red bone marrow doses range up to 2 Gy with a mean of 0.3 Gy and a median of 0.2 Gy. Between 1953 and 2005, 93 first primary cases of leukemia, including 23 cases of chronic lymphatic leukemia (CLL), were ascertained among the cohort members. A significant linear dose-response relationship was seen for leukemias other than CLL (P leukemias other than CLL and less than 0 (95% upper bound 1.4) for CLL.

  9. Radiation Exposure Effects and Shielding Analysis of Carbon Nanotube Materials

    Science.gov (United States)

    Wilkins, Richard; Armendariz, Lupita (Technical Monitor)

    2002-01-01

    Carbon nanotube materials promise to be the basis for a variety of emerging technologies with aerospace applications. Potential applications to human space flight include spacecraft shielding, hydrogen storage, structures and fixtures and nano-electronics. Appropriate risk analysis on the properties of nanotube materials is essential for future mission safety. Along with other environmental hazards, materials used in space flight encounter a hostile radiation environment for all mission profiles, from low earth orbit to interplanetary space.

  10. Radiation resistance of copper alloys at high exposure levels

    Energy Technology Data Exchange (ETDEWEB)

    Garner, F.A. (Pacific Northwest Lab., Richland, WA (USA)); Zinkle, S.J. (Oak Ridge National Lab., TN (USA))

    1990-08-01

    Copper alloys are currently being considered for high heat flux applications in fusion power devices. A review is presented of the results of two separate series of experiments on the radiation response of copper and copper alloys. One of these involved pure copper and boron-doped copper in the ORR mixed spectrum reactor. The other series included pure copper and a wide array of copper alloys irradiated in the FFTF fast reactor 16 refs., 13 figs.

  11. Expression of P53 protein after exposure to ionizing radiation

    Science.gov (United States)

    Salazar, A. M.; Salvador, C.; Ruiz-Trejo, C.; Ostrosky, P.; Brandan, M. E.

    2001-10-01

    One of the most important tumor suppressor genes is p53 gene, which is involved in apoptotic cell death, cell differentiation and cell cycle arrest. The expression of p53 gene can be evaluated by determining the presence of P53 protein in cells using Western Blot assay with a chemiluminescent method. This technique has shown variabilities that are due to biological factors. Film developing process can influence the quality of the p53 bands obtained. We irradiated tumor cell lines and human peripheral lymphocytes with 137Cs and 60Co gamma rays to standardize irradiation conditions, to compare ionizing radiation with actinomycin D and to reduce the observed variability of P53 protein induction levels. We found that increasing radiation doses increase P53 protein induction while it decreases viability. We also conclude that ionizing radiation could serve as a positive control for Western Blot analysis of protein P53. In addition, our results show that the developing process may play an important role in the quality of P53 protein bands and data interpretation.

  12. [Stem cell derived therapy for cutaneous radiation exposure].

    Science.gov (United States)

    Rezvani, M

    2013-12-01

    Radiation injury to skin results in a variety of deterministic effects including inflammatory reactions and cell depletion leading to distinct clinical symptoms following a defined time pattern. Therapeutic approaches are still limited, a complete restitution of affected areas is so far impossible. In the last few years increasing experimental knowledge about acquisition and administration of autologous stem cells also in the field of radiation injuries has been obtained. Evidence reviewed in this article shows that the beneficial effects of stem cell transplantation are not necessarily due to the replacement of damaged cells by transplanted cells but most probably due in the most part to a paracrine effect. Transplanted cells secrete bioactive factors that initiate the stimulation of the host stem cells to regenerate the damaged tissues. Transplanted stem cells produce trophic factors which aid the systemic healing of the victims. Furthermore, administration of stem cell secretomes in the form of conditioned media containing microvesicles or exosomes can be as effective as administering the stem cells. This hypothesis is supported by findings that cell-free derivatives from hMSCs were useful for wound healing purposes and could circumvent the need for intact cells. Furthermore, the beneficial effect of MSC injection on reperfusion and tissue damage in a mouse model of hind limb ischemia could be attributed to paracrine mechanisms with local release of arteriogenic cytokines. Further evaluation of the paracrine potential of autologous stem cells may open new means for treatment of acute as well as chronic sequelae of cutaneous radiation injuries.

  13. Public radiation exposures from a CANDESAL Co-generation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Khaloo, R. [Atomic Energy of Canada Limited, Mississauga, ON (Canada); Simanjuntak, A. [PRSG-BATAN, Tangerang (Indonesia)

    1998-07-01

    As part of an evaluation of the practical and economic viability of using the CANDESAL (CANDU DESALINATION) approach to desalinate water in an Indonesian environment, radiation doses to members of the public were conservatively calculated. The calculations show there is a negligible radiological impact on the public. Conservative radiation doses to members of the critical group (an adult male and a 1-year-old infant) were calculated, according to the CAN/CSA N288.1-M87 compartmental pathways analysis methodology, and show that use of the desalinated water supply would increase the dose to a member of the critical group (adult or infant) by less than 20 {mu}Sv{center_dot}a{sup -1}. About 99% of the dose from the CANDESAL facility is from tritiated heavy water (DTO or HTO) and the rest is from trace concentrations of beta and gamma emitters. The doses to a member of the critical group from a combined CANDU 6 and CANDESAL Co-generation Facility will be less than 4% of the ICRP-60 recommended effective dose limit of 1000 {mu}Sv{center_dot}a{sup -1} to a member of the public. These doses are not only a small fraction of the regulatory dose limits, but are also within the normal variations of natural background radiation levels. (author)

  14. Comparative Measurements of Cosmic Radiation Monitors for Aircrew Exposure Assessment

    Science.gov (United States)

    Getley, I. L.; Bennett, L. G. I.; Boudreau, M. L.; Lewis, B. J.; Green, A. R.; Butler, A.; Takada, M.; Nakamura, T.

    Various commercially available electronic personal dosimeters (EPDs) have recently been flown on numerous scheduled airline flights in order to determine their viability as small, convenient monitors to measure cosmic radiation at altitude. Often, frequent flyers or airline crew will acquire such dosimeters and report the readings from their flights, without due regard for the mixed radiation field at altitude, which is different from the intended fields on land. A sampling of EPDs has been compared to two types of spectrometers, which measure the total radiation spectrum. The "HAWK" tissue equivalent proportional counter is considered a reference instrument and measures the total dose equivalent H*(10). The Liulin-4N and 4SN linear energy transfer spectrometers each have a silicon semiconductor-based PIN diode detector which provides an absorbed dose, D, but have been further developed to provide H*(10). A Thermo Electron FH41B and B-10, and EPD-N2, and several personal dosimeters (Fuji NRY-21 and NRF-20, and RADOS DIS-100) were also flown.

  15. Comparative Measurements of Cosmic Radiation Monitors for Aircrew Exposure Assessment

    Science.gov (United States)

    Getley, I. L.; Bennett, L. G. I.; Boudreau, M. L.; Lewis, B. J.; Green, A. R.; Butler, A.; Takada, M.; Nakamura, T.

    Various commercially available electronic personal dosimeters (EPDs) have recently been flown on numerous scheduled airline flights in order to determine their viability as small, convenient monitors to measure cosmic radiation at altitude. Often, frequent flyers or airline crew will acquire such dosimeters and report the readings from their flights, without due regard for the mixed radiation field at altitude, which is different from the intended fields on land. A sampling of EPDs has been compared to two types of spectrometers, which measure the total radiation spectrum. The “HAWK” tissue equivalent proportional counter is considered a reference instrument and measures the total dose equivalent H * (10). The Liulin-4N and 4SN linear energy transfer spectrometers each have a silicon semiconductor-based PIN diode detector which provides an absorbed dose, D, but have been further developed to provide H * (10). A Thermo Electron FH41B and B-10, and EPD-N2, and several personal dosimeters (Fuji NRY-21 and NRF-20, and RADOS DIS-100) were also flown.

  16. [Occupational radiation exposures during maintenance activities at nuclear power plants].

    Science.gov (United States)

    Imahori, A

    1987-11-01

    Occupational exposures at nuclear power plants occur mostly during maintenance activities rather than during routine reactor operation. In this paper, statistical summaries of occupational exposures during routine maintenance activities for the years 1982-84 at nuclear power plants in Japan are presented, including comparison of the exposure levels by reactor type and by plant age. Average annual collective doses per reactor for BWRs and PWRs are 7.30 man-Sv and 2.84 man-Sv, respectively, and 78% and 89% of annual doses are incurred during maintenance activities. Average annual outage days of BWRs and PWRs for routine maintenance are 102 d and 97 d. Annual collective doses per reactor, most of which occur during maintenance activities, usually increase with plant age. Higher collective doses are observed for routine maintenance performed on older reactors as compared to newer reactors, especially in BWRs. Collective doses accrued during respective routine maintenance activities have a significant correlation with duration of maintenance and number of workers involved in maintenance.

  17. MONITORING OF EXPOSURE RADIATION DOSES LOADS FROM MEDICAL EXPOSURE TO POPULATION OF THE KIROV REGION

    Directory of Open Access Journals (Sweden)

    B. N. Skolotnev

    2012-01-01

    Full Text Available The paper analyzes medical exposure to population of the Kirov region during the period of 50 years (1961–2011 from the main types of X-ray procedures. Steady eduction trend of exposure levels to population with increase of X-ray surveys frequency has been found.

  18. Effects of Radiation Exposure From Cardiac Imaging: How Good Are the Data?

    Science.gov (United States)

    Einstein, Andrew J.

    2012-01-01

    Concerns about medical exposure to ionizing radiation have become heightened in recent years due to rapid growth in procedure volumes and the high radiation doses incurred from some procedures. This article summarizes the evidence base undergirding concerns about radiation exposure in cardiac imaging. After classifying radiation effects, explaining terminology used to quantify the radiation received by patients, and describing typical doses from cardiac imaging procedures, I address the major epidemiological studies having bearing on radiation effects at doses comparable to those received by patients undergoing cardiac imaging. These include studies of atomic bomb survivors, nuclear industry workers, and children exposed in utero to x-rays, all of which have evidenced increased cancer risks at low doses. Additional higher dose epidemiological studies of cohorts exposed to radiation in the context of medical treatment are described and found to be generally compatible with these cardiac-dose-level studies, albeit with exceptions. Using risk projection models developed by the US National Academies that incorporate these data and reflect several evidence-based assumptions, cancer risk from cardiac imaging can be estimated and compared to benefits from imaging. Several ongoing epidemiological studies will provide better understanding of radiation-associated cancer risks. PMID:22300689

  19. Student and intern awareness of ionising radiation exposure from common diagnostic imaging procedures.

    Science.gov (United States)

    Zhou, G Z; Wong, D D; Nguyen, L K; Mendelson, R M

    2010-02-01

    This study aims to evaluate medical student and intern awareness of ionising radiation exposure from common diagnostic imaging procedures and to suggest how education could be improved. Fourth to sixth year medical students enrolled at a Western Australian university and interns from three teaching hospitals in Perth were recruited. Participants were asked to complete a questionnaire consisting of 26 questions on their background, knowledge of ionising radiation doses and learning preferences for future teaching on this subject. A total of 331 completed questionnaires were received (95.9%). Of the 17 questions assessing knowledge of ionising radiation, a mean score of 6.0 was obtained by respondents (95% CI 5.8-6.2). Up to 54.8% of respondents underestimated the radiation dose from commonly requested radiological procedures. Respondents (11.3 and 25.5%) incorrectly believed that ultrasound and MRI emit ionising radiation, respectively. Of the four subgroups of respondents, the intern doctor subgroup performed significantly better (mean score 6.9, P medical student subgroups. When asked for the preferred method of teaching for future radiation awareness, a combination of lectures, tutorials and workshops was preferred. This study has clearly shown that awareness of ionising radiation from diagnostic imaging is lacking among senior medical students and interns. The results highlight the need for improved education to minimise unnecessary exposure of patients and the community to radiation. Further studies are required to determine the most effective form of education.

  20. Methods for reducing patient radiation exposure during proton therapy for eye disease

    Directory of Open Access Journals (Sweden)

    Victor A. Bakaev

    2017-06-01

    Full Text Available The paper is dedicated to techniques for reduction of background radiation in the room for conducting proton eye radiotherapy. The necessity of this reduction stems from the health risk of low-dose effect on the personnel and patients. We have touched the aspects of background reduction both at the cost of secondary particles, produced in beam-forming systems, and the dose reduction for the patient's healthy tissue (when carrying out beam therapy owing to correct assessment of the biological effects of protons with energies up to 60MeV. The obtained calculation results prove that an increase in the proton beam diameter provides the possibility of reducing the background radiation by more than a factor of three in the room and of correspondingly decreasing the body's radiation exposure. It is necessary to take correct account of RBE to reduce the radiation exposure of adjacent organs.