Incidence of Diabetes in the Atomic Bomb Survivors: 1969-2015

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 9,131 participants without diabetes at baseline were observed through biennial clinical exams from 1969-2015. 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, 1,417 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 Truman Administration and Non-use of the Atomic Bomb During the Korean War, June 1950 to January 1953

<p>This thesis examines the Truman administration's non-use of nuclear weapons during the Korean War, June 1950 to January 1953. It investigates the entirety of the Truman administration's experience of the Korean War, rather than focusing on certain key periods. By examining official documentation, memoirs, newspaper reports, and information about public opinion, this thesis explains why the Truman administration chose not to utilise the atomic arsenal. It examines the opinions and influence of significant decision makers such as President Harry S. Truman, Secretary of State Dean Acheson, and Director of the Policy Planning Staff Paul H. Nitze. Truman, as president and ultimate decision maker, will be paid special attention, not least on account of his unique experience of having ordered the atomic attacks on Japan in 1945. This thesis also looks into the position of high-ranking military officers, such as General Omar N. Bradley, General Hoyt S. Vandenberg, and General Matthew B. Ridgway. In order to explain non-use, this thesis also investigates the influence of foreign allies and foreign opinion, particularly that expressed by the United Kingdom, the United States' most important ally. The role of public opinion within the United States is also considered. By examining in detail all of these factors and building a composite picture of the forces acting upon the administration, this thesis provides a more rounded and nuanced view of non-use by the Truman administration during the Korean War than that offered by the existing scholarship. It demonstrates that non-use was always a complex and problematic matter.</p>

The Truman Administration and Non-use of the Atomic Bomb During the Korean War, June 1950 to January 1953

<p>This thesis examines the Truman administration's non-use of nuclear weapons during the Korean War, June 1950 to January 1953. It investigates the entirety of the Truman administration's experience of the Korean War, rather than focusing on certain key periods. By examining official documentation, memoirs, newspaper reports, and information about public opinion, this thesis explains why the Truman administration chose not to utilise the atomic arsenal. It examines the opinions and influence of significant decision makers such as President Harry S. Truman, Secretary of State Dean Acheson, and Director of the Policy Planning Staff Paul H. Nitze. Truman, as president and ultimate decision maker, will be paid special attention, not least on account of his unique experience of having ordered the atomic attacks on Japan in 1945. This thesis also looks into the position of high-ranking military officers, such as General Omar N. Bradley, General Hoyt S. Vandenberg, and General Matthew B. Ridgway. In order to explain non-use, this thesis also investigates the influence of foreign allies and foreign opinion, particularly that expressed by the United Kingdom, the United States' most important ally. The role of public opinion within the United States is also considered. By examining in detail all of these factors and building a composite picture of the forces acting upon the administration, this thesis provides a more rounded and nuanced view of non-use by the Truman administration during the Korean War than that offered by the existing scholarship. It demonstrates that non-use was always a complex and problematic matter.</p>

Japanese pediatric and adult atomic bomb survivor dosimetry: potential improvements using the J45 phantom series and modern Monte Carlo transport

The radiation exposure estimates for the atomic bomb survivors at Hiroshima and Nagasaki have evolved over the past several decades, reflecting a constant strive by the Radiation Effects Research Foundation (RERF) to provide thorough dosimetry to their cohort. Recently, a working group has introduced a new series of anatomical models, called the J45 phantom series, which improves upon those currently used at RERF through greater age resolution, sex distinction, anatomical realism, and organ dose availability. To evaluate the potential dosimetry improvements that would arise from their use in an RERF Dosimetry System, organ doses in the J45 series are evaluated here using environmental fluence data for 20 generalized survivor scenarios pulled directly from the current dosimetry system. The energy- and angle-dependent gamma and neutron fluences were converted to a source term for use in MCNP6, a modern Monte Carlo radiation transport code. Overall, the updated phantom series would be expected to provide dose improvements to several important organs, including the active marrow, colon, and stomach wall (up to 20, 20, and 15% impact on total dose, respectively). The impacts were especially significant for neutron dose estimates (up to a two-fold difference) and within organs which were unavailable in the previous phantom series. These impacts were consistent across the 20 scenarios and are potentially even greater when biological effectiveness of the neutron dose component is considered. The entirety of the dosimetry results for all organs are available as supplementary data, providing confident justification for potential future DS workflows utilizing the J45 phantom series.

How Safe Are Radiation Doses in Diagnostic Radiology? A Historical Perspective and Review of Current Evidence

The “no dose is safe” linear no-threshold (LNT) model forms the basis for radiation safety in radiology practice. This model has its origins in observations of germline mutations in fruit flies exposed to X-rays. After World War II, quantitative risk estimates of radiation injury are primarily derived from the atomic bomb survivor Life Span Study. Current understanding of tissue response to radiation has raised doubts about the validity of LNT model at low doses encountered in the practice of diagnostic radiology. This article traces the evolution of basic radiation safety concepts and provides a bird's eye view of the Life Span Study and other studies which throw light on the matter. The arguments for an alternative, threshold, or even hermetic models of dose response are examined. The relevance of these developments to the nuclear power industry is also outlined.

What Would Become of Nuclear Risk if Governments Changed Their Regulations to Recognize the Evidence of Radiation’s Beneficial Health Effects for Exposures That Are Below the Thresholds for Detrimental Effects?

The 1953 Atoms for Peace Speech to the United Nations proposed applying nuclear energy to essential needs, including abundant electrical energy. The widespread fear of ionizing radiation from nuclear facilities and medical procedures began after the United States National Academy of Sciences performed a study of radiation dangers to the human genome. This study, initiated and managed by an oil industry benefactor, recommended in 1956 that the risk of radiation-induced mutations be assessed using the linear no-threshold dose-response model instead of the threshold model. It was followed by a study that wrongly linked low radiation to cancer among the atomic bomb survivors. The ensuing controversy resulted in a compromise. The National Committee on Radiation Protection adopted the precautionary principle policy in 1959, justified by fear of cancer and lack of knowledge. The United States and all other countries followed this recommendation, which remains unchanged 62 years later. Its impact on nuclear energy and medicine has been profound. Many costly regulations have been enacted to prevent very unlikely human or equipment failures—failures that would lead to radiation exposures that are below the dose thresholds for lasting harmful effects. Potential low-dose radiation therapies, against inflammation, cancer, autoimmune, and neurodegenerative diseases, are shunned.

Lifetime Risk Assessment of Lung Cancer Incidence for Nonsmokers in Japan Considering the Joint Effect of Radiation and Smoking Based on the Life Span Study of Atomic Bomb Survivors

Background: The lifetime risk of lung cancer incidence due to radiation for nonsmokers is overestimated because of the use of the average cancer baseline risk among a mixed population, including smokers. In recent years, the generalized multiplicative (GM)-excess relative risk (ERR) model has been developed in the life span study of atomic bomb survivors to consider the joint effect of radiation and smoking. Based on this background, this paper discusses the issues of radiation risk assessment considering smoking in two parts.Materials and Methods: In Part 1, we proposed a simple method of estimating the baseline risk for nonsmokers using current smoking data. We performed sensitivity analysis on baseline risk estimation to discuss the birth cohort effects. In Part 2, we applied the GM-ERR model for Japanese smokers to calculate lifetime attributable risk (LAR). We also performed a sensitivity analysis using other ERR models (e.g., simple additive (SA)-ERR model).Results and Discussion: In Part 1, the lifetime baseline risk from mixed population including smokers to nonsmokers decreased by 54% (44%–60%) for males and 24% (18%–29%) for females. In Part 2, comparison of LAR between SA- and GM-ERR models showed that if the radiation dose was ≤200 mGy or less, the difference between these ERR models was within the standard deviation of LAR due to the uncertainty of smoking information.Conclusion: The use of mixed population for baseline risk assessment overestimates the risk for lung cancer due to low-dose radiation exposure in Japanese males.