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Although some adverse effects on neurocognitive function have been reported in children and adolescents irradiated prenatally during the atomic bombings and the Chernobyl nuclear accident, little information is available for effects on the elderly. Here we evaluate the effects of prenatal exposure to atomic bomb radiation on subjective neurocognitive function in aged survivors. To evaluate neurocognitive impairment, we mailed the Neurocognitive Questionnaire (NCQ), a self-administered scale, to prenatally exposed survivors, including clinic visitors and non-visitors at the time of the 2011 and 2013 Adult Health Study (AHS) examinations. We received replies from 444 individuals (mean age, 66.9 ± 0.6 years). After adjusting for sex, city, and educational background, we found no significant effects of radiation, clinic visit, or interaction between radiation and clinic visit on the scores of the 4 NCQ factors of metacognition, emotional regulation, motivation/organization, and processing speed. Even in analyses considering gestational age at the time of the bombings, none of the 4 NCQ factor scores was related to maternal uterine dose. There remains the limitation that this study consisted of healthy survivors, but we found no significant radiation effect on late-life cognition in people prenatally exposed to atomic bomb radiation., (©2023 by Radiation Research Society. All rights of reproduction in any form reserved.)

Background: A mathematical model of the radiation-induced cancer was devised to explain the change of incidence rates pursued by Radiation Effect Research Foundation for 25 years., Aim: The aim of this work is construction of mechanisms of radiation-induced cancer and cancers observed in the daily life., Methods and Results: First, we found a way to separate spontaneous cancers from radiation-induced cancers observed among atomic-bomb victims in Hiroshima and Nagasaki districts by using a constructed algorithm. The isolated incidence rates of radiation-induced cancers were reproduced by a two-stage model mechanical collision of impinging radiation with cells and succeeding mutation of the damaged cell to cancer. This model satisfactorily reproduced observed solid cancer incidence rates. We further attempted to construct a mathematical model for the age-dependence of spontaneous cancers appearing in the daily life and concluded that the cancer should be generated at cell division., Conclusion: With these findings, we reached to a conclusion that cancers may be suppressed by eliminating damaged cells with mild-dose radiation., (© 2022 The Authors. Cancer Reports published by Wiley Periodicals LLC.)

In the post-Hiroshima era, atomic cities-designed to survive a nuclear attack-remain in the science fiction realm. Yet Hungarian émigré Paul Laszlo, a successful architect in Southern California suburbia, had a utopian vision for a futuristic, paradoxically luxurious atomic city he called "Atomville," never built but nonetheless seriously proposed. Laszlo was one of the very few architects known to venture into atomic survival on this scale. This article focuses on why the architectural profession for the most part ignored the issues raised by the atomic bomb, and on Laszlo's role as an outlier. It also deals with the genesis of Atomville and its place among the many unrealized ideas put forward in the 1940s and 1950s for urban survival, including underground buildings, urban dispersal, linear cities, and cluster cities.

There are two types of exposure to atomic bomb (A-bomb) radiation: exposure to initial radiation released at the time of the detonation of the bomb, and exposure to residual radiation, which remains afterwards. Health hazards caused by exposure from residual radiation have not yet been clarified. The purpose of our study was to reveal the relationships between mortality risk from solid cancer and residual radiation based on data from the early entrants to Hiroshima. It is hard to identify the individual residual radiation doses. However, these are assumed to depend on the date of entry and the entrants' behavior. Individual behavior is thought to be closely related to gender and age at exposure. We investigated a cohort of 45 809 individuals who were living in Hiroshima Prefecture on 1 January 1970 and were registered on the Database of Atomic Bomb Survivors as entrants after the bombing. Poisson regression methods were used to estimate excess relative risks (ERR) with data cross-classified by sex, age at entry, and date of entry. In males in their 20s, 30s, and 40s at entry and in females less than 10 years old and in their 40s at entry, solid cancer mortality risks were significantly higher among persons who entered the city on the day of the bombing than those who entered three or more days later. With adjustments for the age-dependent sensitivities to radiation exposure, it was extrapolated that middle-aged people who entered the city on the day of the bombing were exposed to higher levels of residual radiation than younger people., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Recent analysis of all solid cancer incidence (1958-2009) in the Life Span Study (LSS) revealed evidence of upward curvature in the radiation dose response among males but not females. Upward curvature in sex-averaged excess relative risk (ERR) for all solid cancer mortality (1950-2003) was also observed in the 0-2 Gy dose range. As reasons for non-linearity in the LSS are not completely understood, we conducted dose-response analyses for all solid cancer mortality and incidence applying similar methods [1958-2009 follow-up, DS02R1 doses, including subjects not-in-city (NIC) at the time of the bombing] and statistical models. Incident cancers were ascertained from Hiroshima and Nagasaki cancer registries, while cause of death was ascertained from death certificates throughout Japan. The study included 105,444 LSS subjects who were alive and not known to have cancer before January 1, 1958 (80,205 with dose estimates and 25,239 NIC subjects). Between 1958 and 2009, there were 3.1 million person-years (PY) and 22,538 solid cancers for incidence analysis and 3.8 million PY and 15,419 solid cancer deaths for mortality analysis. We fitted sex-specific ERR models adjusted for smoking to both types of data. Over the entire range of doses, solid cancer mortality dose-response exhibited a borderline significant upward curvature among males (P = 0.062) and significant upward curvature among females (P = 0.010); for solid cancer incidence, as before, we found a significant upward curvature among males (P = 0.001) but not among females (P = 0.624). The sex difference in magnitude of dose-response curvature was statistically significant for cancer incidence (P = 0.017) but not for cancer mortality (P = 0.781). The results of analyses in the 0-2 Gy range and restricted lower dose ranges generally supported inferences made about the sex-specific dose-response shape over the entire range of doses for each outcome. Patterns of sex-specific curvature by calendar period (1958-1987 vs. 1988-2009) and age at exposure (0-19 vs. 20-83) varied between mortality and incidence data, particularly among females, although for each outcome there was an indication of curvature among 0-19-year-old male survivors in both calendar periods and among 0-19-year-old female survivors in the recent period. Collectively, our findings indicate that the upward curvature in all solid cancer dose response in the LSS is neither specific to males nor to incidence data; its evidence appears to depend on the composition of sites comprising all solid cancer group and age at exposure or time. Further follow up and site-specific analyses of cancer mortality and incidence will be important to confirm the emerging trend in dose-response curvature among young survivors and unveil the contributing factors and sites., (©2022 by Radiation Research Society. All rights of reproduction in any form reserved.)

Context: Recent epidemiological studies have shown increased risk of diabetes among childhood cancer survivors who received high therapeutic doses of radiation, particularly to the total body or to the abdomen. However, the effect of low-to-moderate dose radiation (<4 Gy) on the risk of diabetes is still unknown., Objectives: To investigate the radiation effect on diabetes incidence among atomic bomb (A-bomb) survivors, and whether the dose response is modified by other factors including city, sex, and age at time of bombing (ATB)., Methods: 9131 participants without diabetes at baseline were observed through biennial clinical exams from 1969 to 2015. A Cox proportional hazards model was used to estimate hazard ratios (HR) to evaluate the dose response for diabetes incidence., Results: During the study period, 1417 incident diabetes cases were identified. The overall crude incidence rate was 7.01/103 person-years. Radiation dose was significantly associated with diabetes incidence, with effect modification by city and age ATB. In Hiroshima, at ages 10 and 30 ATB, the HRs at 1 Gy of pancreatic radiation dose were 1.47 (95% CI, 1.31-1.66) and 1.13 (95% CI, 0.97-1.31), respectively. However, no significant radiation dose response was observed at these ages in Nagasaki. The HR for radiation dose was higher among those who were younger ATB and decreased 1% for each additional year of age., Conclusions: Among A-bomb survivors, a radiation association was suggested for incidence of diabetes. Results were inconsistent by city and age ATB, which could indicate potential confounding of the radiation association with diabetes., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

The dose rate of atomic bomb (A-bomb) radiation to the survivors has still remained unclear, although the dose-response data of A-bomb cancers has been taken as a standard in estimating the cancer risk of radiation and the dose and dose-rate effectiveness factor (DDREF). Since the applicability of the currently used DDREF of 2 derived from A-bomb data is limited in a narrow dose-rate range, 0.25-75 Gy/min as estimated from analysis of DS86 dosimetry data in the present study, a non-tumor dose (Dnt) was applied in an attempt to gain a more universal dose-rate effectiveness factor (DREF), where Dnt is an empirical parameter defined as the highest dose at which no statistically significant tumor increase is observed above the control level and its magnitude depends on the dose rate. The new DREF values were expressed as a function of the dose rate at four exposure categories, i.e. partial body low LET, whole body low linear energy transfer (LET), partial body high LET and whole body high LET and provided a value of 14 for environmental level radiation at a dose rate of 10-9 Gy/min for whole body low LET., (© The Author(s) 2021. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology.)

Competing Interests: The author declares no conflicts of interest.

The onset of nuclear warfare in Hiroshima and Nagasaki had far-reaching implications for the world of medicine. The study of the A-bomb and its implications led to the launching of new fields and avenues of research, most notably in genetics and radiation studies. Far less understood and under-studied was the impact of nuclear research on psychiatric medicine. Psychological research, however, was a major focus of post-war military and civilian research into the bomb. This research and the perceived revolutionary impact of atomic energy and warfare on society, this paper argues, played an important role in the global development of post-war psychiatry. Focusing on psychiatrists in North America, Japan and the United Nations, this paper examines the reaction of the profession to the nuclear age from the early post-war period to the mid 1960s. The way psychiatric medicine related to atomic issues, I argue, shifted significantly between the immediate post-war period and the 1960s. While the early post-war psychiatrists sought to help society deal with and adjust to the new nuclear reality, later psychiatrists moved towards a more radical position that sought to resist the establishment's efforts to normalise the bomb and nuclear energy. This shift had important consequences for research into the psychological trauma suffered by victims of nuclear warfare, which, ultimately, together with other research into the impact of war and systematic violence, led to our current understanding of Post-Traumatic Stress Disorder (PTSD).

Context: The risk of thyroid cancer increases and persists for decades among individuals exposed to ionizing radiation in childhood, although the long-term effects of childhood exposure to medium to low doses of radiation on thyroid dysfunction and autoimmune thyroid diseases have remained unclear., Objective: To evaluate radiation dose responses for the prevalence of thyroid dysfunction and autoimmune thyroid disease among atomic bomb survivors exposed in childhood., Design, Setting, and Participants: Hiroshima and Nagasaki atomic bomb survivors who were younger than 10 years old at exposure underwent thyroid examinations at the Radiation Effects Research Foundation between 2007 and 2011, which was 62 to 66 years after the bombing. Data from 2668 participants (mean age, 68.2 years; 1455 women) with known atomic bomb thyroid radiation doses (mean dose, 0.182 Gy; dose range, 0 to 4.040 Gy) were analyzed., Main Outcome and Measures: Dose-response relationships between atomic bomb radiation dose and the prevalence of hypothyroidism, hyperthyroidism (Graves' disease), and positive for antithyroid antibodies., Results: Prevalences were determined for hypothyroidism (129 cases, 7.8%), hyperthyroidism (32 cases of Graves' disease, 1.2%), and positive for antithyroid antibodies (573 cases, 21.5%). None of these was associated with thyroid radiation dose. Neither thyroid antibody-positive nor -negative hypothyroidism was associated with thyroid radiation dose. Additional analyses using alternative definitions of hypothyroidism and hyperthyroidism found that radiation dose responses were not significant., Conclusions: Radiation effects on thyroid dysfunction and autoimmune thyroid diseases were not observed among atomic bomb survivors exposed in childhood, at 62 to 66 years earlier. The cross-sectional design and survival bias were limitations of this study., (Copyright © 2017 Endocrine Society)

Heart disease (HD) mortality is the second leading cause of death in Japan. The HD mortality risk among Atomic bomb survivors is slightly positive but shows a statistically significant dose-response relationship with initial radiation dose, as reported by the Radiation Effects Research Foundation. In that report, dosimetry was based on initial radiation only, with the effect of indirect radiation dose not taken into consideration. The atomic bomb radiation, however, consisted of both initial and residual radiation. We reevaluated the dose-response relationship for HD mortality using exposure distance (ground distance between the location where exposed and the hypocenter) as a surrogate indicator of radiation dose. At Hiroshima University, a cohort study has been conducted with Hiroshima Atomic Bomb Survivors (ABS) since 1970. We selected 29605 subjects from the ABS who were exposed at 3.5 km or less from the hypocenter and alive on January 1, 1970. These subjects, referred to as "Hiroshima hibakusha" in this paper, were followed until December 31, 2010. We stratified the cohort data with respect to sex and age at the time of bombing (ATB) into 10-year age groups. For each stratum, by applying an extended Cox regression model with time-dependent covariates, we analyzed the risk of HD mortality using either initial radiation dose or exposure distance as an explanatory variable. The results indicate a high excess risk in males and older age ATB females who were exposed near the hypocenter. This difference may be explained by the effect of female sex hormone on the circulatory system among young age ATB females. Some unknown risk factor related to exposure distance was also implicated in the elevated risk of HD among the Hiroshima hibakusha, especially in males. This necessitates further study.

Several studies have been conducted on cerebrovascular disease mortality in Atomic bomb survivors. Previous studies have investigated the relationship between mortality and initial radiation dose after adjusting for the effects of sex and age at the time of the bombing (ATB), and detected a weak (but statistically significant) dose-response relationship was detected. The objective of the present study was to examine whether the sex- and age ATB-specific cerebrovascular disease mortality among Hiroshima atomic bomb survivors can be explained by the initial radiation dose. At Hiroshima University, a cohort study has been conducted with Hiroshima Atomic Bomb Survivors (ABS) since 1970. We selected 30,378 subjects from the ABS who were exposed at 3.5 km or less from the hypocenter and still alive on January 1, 1970. These subjects were followed up until December 31, 2010. The cohort data were stratified with respect to sex and age ATB into 10-year age groups. For each stratum, using Cox regression, we performed survival analyses of the risk of cerebrovascular mortality using the initial radiation dose and the exposure distance (the ground distance between the exposure location and the hypocenter) as explanatory variables. The results indicated that the risks to females exposed at 10 to 19 years old were highly dependent on the initial radiation dose (hazard ratio: 1.51, p < 0.001), while the risks to males were not. There might exist some radiation exposure effects limited to women who were in their teens at the time of exposure. However, the background mechanisms remain unclear, necessitating further study.

Following the atomic bomb attacks on Japan in 1945, scientists from the United States and Japan joined together to study the Hibakusha - the bomb affected people in what was advertised as a bipartisan and cooperative effort. In reality, despite the best efforts of some very dedicated and earnest scientists, the early years of the collaboration were characterized by political friction, censorship, controversy, tension, hostility, and racism. The 70-year history, scientific output and cultural impact of the Atomic Bomb Casualty Commission and the Radiation Effects Research Foundation are described in the context of the development of Occupied Japan.

Groups of Japanese and American scientists, supported by international collaborators, have worked for many years to ensure the accuracy of the radiation dosimetry used in studies of health effects in the Japanese atomic bomb survivors. Reliable dosimetric models and systems are especially critical to epidemiologic studies of this population because of their importance in the development of worldwide radiation protection standards. While dosimetry systems, such as Dosimetry System 1986 (DS86) and Dosimetry System 2002 (DS02), have improved, the research groups that developed them were unable to propose or confirm an additional contribution by residual radiation to the survivor's total body dose. In recognition of the need for an up-to-date review of residual radiation exposures in Hiroshima and Nagasaki, a half-day technical session was held for reports on newer studies at the 59 th Annual HPS Meeting in 2014 in Baltimore, MD. A day-and-a-half workshop was also held to provide time for detailed discussion of the newer studies and to evaluate their potential use in clarifying the residual radiation exposure to atomic bomb survivors at Hiroshima and Nagasaki. The process also involved a re-examination of very early surveys of radioisotope emissions from ground surfaces at Hiroshima and Nagasaki and early reports of health effects. New insights were reported on the potential contribution to residual radiation from neutron-activated radionuclides in the airburst's dust stem and pedestal and in unlofted soil, as well as from fission products and weapon debris from the nuclear cloud. However, disparate views remain concerning the actual residual radiation doses received by the atomic bomb survivors at different distances from the hypocenter. The workshop discussion indicated that measurements made using thermal luminescence and optically stimulated luminescence, like earlier measurements, especially in very thin layers of the samples, could be expanded to detect possible radiation exposures to beta particles and to determine their significance plus the extent of the various residual radiation areas at Hiroshima and Nagasaki. Other suggestions for future residual radiation studies are included in this workshop report.

Background: No clear epidemiological hereditary effects of radiation exposure in human beings have been reported. However, no previous studies have investigated mortality into middle age in a population whose parents were exposed to substantial amounts of radiation before conception. We assessed mortality in children of the atomic bomb survivors after 62 years of follow-up., Methods: In this prospective cohort study, we assessed 75 327 singleton children of atomic bomb survivors in Hiroshima and Nagasaki and unexposed controls, born between 1946 and 1984, and followed up to Dec 31, 2009. Parental gonadal doses of radiation from the atomic bombings were the primary exposures. The primary endpoint was death due to cancer or non-cancer disease, based on death certificates., Findings: Median follow-up was 54·3 years (IQR 45·4-59·3). 5183 participants died from disease. The mean age of the 68 689 surviving children at the end of follow-up was 53·1 years (SD 7·9) with 15 623 (23%) older than age 60 years. For parents who were exposed to a non-zero gonadal dose of radiation, the mean dose was 264 mGy (SD 463). We detected no association between maternal gonadal radiation exposure and risk of death caused by cancer (hazard ratio [HR] for 1 Gy change in exposure 0·891 [95% CI 0·693-1·145]; p=0·36) or risk of death caused by non-cancer diseases (0·973 [0·849-1·115]; p=0·69). Likewise, paternal exposure had no effect on deaths caused by cancer (0·815 [0·614-1·083]; p=0·14) or deaths caused by non-cancer disease (1·103 [0·979-1·241]; p=0·12). Age or time between parental exposure and delivery had no effect on risk of death., Interpretation: Late effects of ionising radiation exposure include increased mortality risks, and models of the transgenerational effects of radiation exposure predict more genetic disease in the children of people exposed to radiation. However, children of people exposed to the atomic bombs in Hiroshima and Nagasaki had no indications of deleterious health effects after 62 years. Epidemiological studies complemented by sensitive molecular techniques are needed to understand the overall effects of preconception exposure to ionising radiation on human beings., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Very high levels of ionizing radiation exposure have been associated with the development of soft-tissue sarcoma. The effects of lower levels of ionizing radiation on sarcoma development are unknown. This study addressed the role of low to moderately high levels of ionizing radiation exposure in the development of soft-tissue sarcoma., Methods: Based on the Life Span Study cohort of Japanese atomic-bomb survivors, 80,180 individuals were prospectively assessed for the development of primary soft-tissue sarcoma. Colon dose in gray (Gy), the excess relative risk, and the excess absolute rate per Gy absorbed ionizing radiation dose were assessed. Subject demographic, age-specific, and survival parameters were evaluated., Results: One hundred and four soft-tissue sarcomas were identified (mean colon dose = 0.18 Gy), associated with a 39% five-year survival rate. Mean ages at the time of the bombings and sarcoma diagnosis were 26.8 and 63.6 years, respectively. A linear dose-response model with an excess relative risk of 1.01 per Gy (95% confidence interval [CI]: 0.13 to 2.46; p = 0.019) and an excess absolute risk per Gy of 4.3 per 100,000 persons per year (95% CI: 1.1 to 8.9; p = 0.001) were noted in the development of soft-tissue sarcoma., Conclusions: This is one of the largest and longest studies (fifty-six years from the time of exposure to the time of follow-up) to assess ionizing radiation effects on the development of soft-tissue sarcoma. This is the first study to suggest that lower levels of ionizing radiation may be associated with the development of soft-tissue sarcoma, with exposure of 1 Gy doubling the risk of soft-tissue sarcoma development (linear dose-response). The five-year survival rate of patients with soft-tissue sarcoma in this population was much lower than that reported elsewhere.

Past exposure to atomic bomb (A-bomb) radiation has exerted various long-lasting deleterious effects on the health of survivors. Some of these effects are seen even after >60 yr. In this study, we evaluated the subclinical inflammatory status of 442 A-bomb survivors, in terms of 8 inflammation-related cytokines or markers, comprised of plasma levels of reactive oxygen species (ROS), interleukin (IL)-6, tumor necrosis factor α (TNF-α), C-reactive protein (CRP), IL-4, IL-10, and immunoglobulins, and erythrocyte sedimentation rate (ESR). The effects of past radiation exposure and natural aging on these markers were individually assessed and compared. Next, to assess the biologically significant relationship between inflammation and radiation exposure or aging, which was masked by the interrelationship of those cytokines/markers, we used multivariate statistical analyses and evaluated the systemic markers of inflammation as scores being calculated by linear combinations of selected cytokines and markers. Our results indicate that a linear combination of ROS, IL-6, CRP, and ESR generated a score that was the most indicative of inflammation and revealed clear dependences on radiation dose and aging that were found to be statistically significant. The results suggest that collectively, radiation exposure, in conjunction with natural aging, may enhance the persistent inflammatory status of A-bomb survivors.

The Radiation Effects Research Foundation succeeded 28 years' worth of activities of the Atomic Bomb Casualty Commission on long-term epidemiological studies in Hiroshima and Nagasaki. It has three major cohorts of atomic bomb survivors, i.e. the Life Span Study (LSS) of 120,000 people, the In Utero Cohort of 3600 and the Second Generation Study (F(1)) of 77,000. The LSS and F(1) studies include a periodic health examination for each sub-cohort, i.e. the Adult Health Study and the F(1) Clinical Study, respectively. An extensive individual dose estimation was conducted and the system was published as the Dosimetry System established in 2002 (DS02). As results of these studies, increases of cancers in relation to dose were clearly shown. Increases of other mortality causes were also observed, including heart and respiratory diseases. There has been no evidence of genetic effects in the survivors' children, including cancer and other multi-factorial diseases. The increase in the expected mortality number in the next 10 y would allow the analyses of further details of the observed effects related to atomic bomb exposures.

Many studies have been conducted by the Radiation Effects Research Foundation (RERF) to assess the radiation effects on human beings of atomic bombs, and numerous data have been collected, including records of medical examinations and questionnaires, analytical results, inventories of biosamples and published or unpublished documentation. Some of those data have been stored and analysed since the Atomic Bomb Casualty Commission (later reorganised as RERF) was established in 1947. RERF has made an effort to establish an archival database system so that an RERF researcher can access data at any time without difficulty. Under development is a new database system with the capability to handle a very large amount of data and permit future bioinformatics analyses of data, such as that required in genomics and proteomics analyses.

This paper describes ultra low-level gamma-ray spectrometry measurements of the (60)Co activity distribution inside one 52 mm and one 41 mm thick steel sample. The samples had been exposed to the Hiroshima atomic bomb and were from the Aioi bridge and the Yokogawa bridge. Both samples were measured in a recent study aiming to back up model calculation of Hiroshima dosimetry. The (60)Co activity distributions found in this study support the assumptions made in the previous study., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The non-cancer mortality data for cerebrovascular disease (CVD) and cardiovascular diseases from Report 13 on the atomic bomb survivors published by the Radiation Effects Research Foundation were analysed to investigate the dose-response for the influence of radiation on these detrimental health effects. Various parametric and categorical models (such as linear-no-threshold (LNT) and a number of threshold and step models) were analysed with a statistical selection protocol that rated the model description of the data. Instead of applying the usual approach of identifying one preferred model for each data set, a set of plausible models was applied, and a sub-set of non-nested models was identified that all fitted the data about equally well. Subsequently, this sub-set of non-nested models was used to perform multi-model inference (MMI), an innovative method of mathematically combining different models to allow risk estimates to be based on several plausible dose-response models rather than just relying on a single model of choice. This procedure thereby produces more reliable risk estimates based on a more comprehensive appraisal of model uncertainties. For CVD, MMI yielded a weak dose-response (with a risk estimate of about one-third of the LNT model) below a step at 0.6 Gy and a stronger dose-response at higher doses. The calculated risk estimates are consistent with zero risk below this threshold-dose. For mortalities related to cardiovascular diseases, an LNT-type dose-response was found with risk estimates consistent with zero risk below 2.2 Gy based on 90% confidence intervals. The MMI approach described here resolves a dilemma in practical radiation protection when one is forced to select between models with profoundly different dose-responses for risk estimates.

Iron can be a potent pro-oxidant and, on this basis, elevated body iron may increase the risk of cancer. Although epidemiological evidence is mixed, there is overall support for this possibility. In addition, because of this same oxidative capacity, body iron levels may alter radiation sensitivity. In the present study, a nested case-control study of breast cancer was conducted in Japanese atomic bomb survivors. Stored serum samples from the Adult Health Study cohort were assayed for ferritin levels and joint statistical analyses were conducted of ferritin and radiation dose on the risk of breast cancer. Serum ferritin is the best feasible indicator of body iron levels in otherwise healthy people. A total of 107 cases and 212 controls were available for analysis. The relative risk (RR) of breast cancer for a 1 log unit increase in ferritin was 1.4 (95% confidence interval 1.1-1.8). This translates to an RR of 1.64 comparing high and low values of the interquartile range among controls (58 and 13.2 ng/mL, respectively). The results support the hypothesis that elevated body iron stores increase the risk of breast cancer. However, the study was inconclusive regarding the question of whether body iron alters radiation-induced breast cancer risk., (© 2011 Japanese Cancer Association.)

Background: The nuclear weapons industry has long been known as a source of beryllium exposure., Methods: A total of 1,004 former workers from a nuclear weapons assembly site in the Midwest were screened for sensitization to beryllium (BeS). The screenings were part of the Department of Energy (DOE) Former Worker Program established in 1996., Results: Twenty-three (2.3%) workers were found sensitized to beryllium and this prevalence was comparable to other DOE sites. Occasional, direct exposure to beryllium through machining and grinding of copper-beryllium (Cu-Be) 2% alloy tools was found to increase the risk of sensitization compared to background exposure (OR = 3.83; 95% CI: 1.04-14.03) with a statistically significant trend (P = 0.03) revealing that particular jobs are associated with sensitization. Exposure potential in this study was estimated based on job titles and not personal exposure information., Conclusions: These results confirm the need to screen workers using beryllium alloy tools in other industries and for consideration of altering work practices., (Copyright © 2010 Wiley-Liss, Inc.)

For 63 years scientists in the Atomic Bomb Casualty Commission and its successor, the Radiation Effects Research Foundation, have been assessing the long-term health effects in the survivors of the atomic bombings of Hiroshima and Nagasaki and in their children. The identification and follow-up of a large population (approximately a total of 200,000, of whom more than 40% are alive today) that includes a broad range of ages and radiation exposure doses, and healthy representatives of both sexes; establishment of well-defined cohorts whose members have been studied longitudinally, including some with biennial health examinations and a high survivor-participation rate; and careful reconstructions of individual radiation doses have resulted in reliable excess relative risk estimates for radiation-related health effects, including cancer and noncancer effects in humans, for the benefit of the survivors and for all humankind. This article reviews those risk estimates and summarizes what has been learned from this historic and unique study.

During the 1960s through 1980s the United States and several other nations developed, and even considered deploying, enhanced-radiation warheads (ERWs). The main effect of ERWs (sometimes called "neutron bombs"), as compared to other types of nuclear weapons, is to enhance radiation casualties while reducing blast and thermal damage to the infrastructure. Five nations were reported to have developed and tested ERWs during this period, but since the termination of the "Cold War" there have been no threats of development, deployment, or use of such weapons. However, if the technology of a quarter of a century ago has been developed, maintained, or even advanced since then, it is conceivable that the grim possibility of future ERW use exists. The type of destruction, initial triage of casualties, distribution of patterns of injury, and medical management of ERWs will be shown to significantly differ from that of fission weapons. Emergency response planners and medical personnel, civilian or military, must be aware of these differences to reduce the horrible consequences of ERW usage and appropriately treat casualties.

Background: : Radiation exposure is an established cause of clinical thyroid cancer, but little is known about radiation effects on papillary microcarcinoma (PMC) of the thyroid, a relatively common subclinical thyroid malignancy. Because the incidence of these small thyroid cancers has been increasing, it is important to better understand them and their relation to radiation., Methods: : PMCs were identified in a subset of 7659 members of the Life Span Study of atomic bomb survivors who had archived autopsy or surgical materials. We conducted a pathology review of these specimens and evaluated the histological features of the tumors and the association between PMCs and thyroid radiation dose., Results: : From 1958 to 1995, 458 PMCs were detected among 313 study subjects. The majority of cancers exhibited pathologic features of papillary thyroid cancers. Overall, 81% of the PMCs were of the sclerosing variant and 91% were nonencapsulated, psammoma bodies that occurred in 13% and calcification was observed in 23%. Over 95% had papillary or papillary-follicular architecture and most displayed nuclear overlap, clear nuclei, and nuclear grooves. Several of these features increased with increasing tumor size, but no association was found with radiation dose. A significant radiation-dose response was found for the prevalence of PMCs (estimated excess odds ratio/Gy = 0.57; 95% confidence interval, 0.01-1.55), with the excess risk observed primarily among women., Conclusions: : Exposure to low-to-moderate doses of ionizing radiation appears to increase the risk of thyroid PMCs, even when exposure occurs during adulthood. Cancer 2010. (c) 2010 American Cancer Society.

Objective: To investigate the degree to which ionising radiation confers risk of mortality from heart disease and stroke., Design: Prospective cohort study with more than 50 years of follow-up., Setting: Atomic bomb survivors in Hiroshima and Nagasaki, Japan., Participants: 86 611 Life Span Study cohort members with individually estimated radiation doses from 0 to >3 Gy (86% received <0.2 Gy)., Main Outcome Measures: Mortality from stroke or heart disease as the underlying cause of death and dose-response relations with atomic bomb radiation., Results: About 9600 participants died of stroke and 8400 died of heart disease between 1950 and 2003. For stroke, the estimated excess relative risk per gray was 9% (95% confidence interval 1% to 17%, P=0.02) on the basis of a linear dose-response model, but an indication of possible upward curvature suggested relatively little risk at low doses. For heart disease, the estimated excess relative risk per gray was 14% (6% to 23%, P<0.001); a linear model provided the best fit, suggesting excess risk even at lower doses. However, the dose-response effect over the restricted dose range of 0 to 0.5 Gy was not significant. Prospective data on smoking, alcohol intake, education, occupation, obesity, and diabetes had almost no impact on the radiation risk estimates for either stroke or heart disease, and misdiagnosis of cancers as circulatory diseases could not account for the associations seen., Conclusion: Doses above 0.5 Gy are associated with an elevated risk of both stroke and heart disease, but the degree of risk at lower doses is unclear. Stroke and heart disease together account for about one third as many radiation associated excess deaths as do cancers among atomic bomb survivors.

Developing a mass-casualty medical response to the detonation of an improvised nuclear device (IND) or large radiological dispersal device (RDD) requires unique advanced planning due to the potential magnitude of the event, lack of warning, and radiation hazards. In order for medical care and resources to be collocated and matched to the requirements, a [US] Federal interagency medical response-planning group has developed a conceptual approach for responding to such nuclear and radiological incidents. The "RTR" system (comprising Radiation-specific TRiage, TReatment, TRansport sites) is designed to support medical care following a nuclear incident. Its purpose is to characterize, organize, and efficiently deploy appropriate materiel and personnel assets as close as physically possible to various categories of victims while preserving the safety of responders. The RTR system is not a medical triage system for individual patients. After an incident is characterized and safe perimeters are established, RTR sites should be determined in real-time that are based on the extent of destruction, environmental factors, residual radiation, available infrastructure, and transportation routes. Such RTR sites are divided into three types depending on their physical/situational relationship to the incident. The RTR1 sites are near the epicenter with residual radiation and include victims with blast injuries and other major traumatic injuries including radiation exposure; RTR2 sites are situated in relationship to the plume with varying amounts of residual radiation present, with most victims being ambulatory; and RTR3 sites are collection and transport sites with minimal or no radiation present or exposure risk and a victim population with a potential variety of injuries or radiation exposures. Medical Care sites are predetermined sites at which definitive medical care is given to those in immediate need of care. They include local/regional hospitals, medical centers, other sites such as nursing homes and outpatient clinics, nationwide expert medical centers (such as cancer or burn centers), and possible alternate care facilities such as Federal Medical Stations. Assembly Centers for displaced or evacuating persons are predetermined and spontaneous sites safely outside of the perimeter of the incident, for use by those who need no immediate medical attention or only minor assistance. Decontamination requirements are important considerations for all RTR, Medical Care, and Assembly Center sites and transport vehicles. The US Department of Health and Human Services is working on a long-term project to generate a database for potential medical care sites and assembly centers so that information is immediately available should an incident occur.

Aim: The aim of the present research is to clarify the nursing care conducted just before and after the atomic bombing of Hiroshima in 1945., Methods: Five surviving nurses, who were registered nursing staff at that time in Hiroshima, offered to participate in this research. Individual interviews were conducted in order to obtain the information concerning the nursing activities in the disaster-stricken areas. The collected information was collated with the documents with regard to the atomic bombing in Hiroshima, and compared with the current studies concerning nursing in disaster., Findings: The five nurses who participated in the study made it clear that, from the day of the bombing, nursing care activities changed moment by moment according to the condition of the radiation victims, the stricken areas and the relief systems. Under these circumstances, the nurses tried to help the victims of the bombing by devising anything useful for nursing care., Conclusion: The research participants left their messages, pointing out that nurses' mental attitude to those in front of them as patients is one of the most important things to keep in mind following any major disaster.

Purpose: The immune systems of the atomic-bomb (A-bomb) survivors were damaged proportionately to irradiation levels at the time of the bombing over 60 years ago. Although the survivor's immune system repaired and regenerated as the hematopoietic system has recovered, significant residual injury persists, as manifested by abnormalities in lymphoid cell composition and function. This review summarizes the long-lasting alterations in immunological functions associated with atomic-bomb irradiation, and discusses the likelihood that damaging effects of radiation on the immune system may be involved partly in disease development so frequently observed in A-bomb survivors., Conclusions: Significant immunological alterations noted include: (i) attrition of T-cell functions, as reductions in mitogen-dependent proliferation and interleukin-2 (IL-2) production; (ii) decrease in helper T-cell populations; and (iii) increase in blood inflammatory cytokine levels. These findings suggest that A-bomb radiation exposure perturbed one or more of the primary processes responsible for T-cell homeostasis and the balance between cell renewal and survival and cell death among naive and memory T cells. Such perturbed T-cell homeostasis may result in acceleration of immunological aging. Persistent inflammation, linked in some way to the perturbation of T-cell homeostasis, is key in addressing whether such noted immunological changes observed in A-bomb survivors are in fact associated with disease development.