Biodefense Project

在环境研究中心进行的大多数剂量学工作都直接或间接地应用于评估涉及环境辐射的生物恐怖主义事件的辐射剂量。自2005年以来，REB所有与生物恐怖主义有关的研究都是根据NIAID和NCI之间的机构间协议资助的。稳定染色体畸变的生物剂量学分析：辐射剂量的生物监测可以为个人和群体提供重要的、独立的辐射照射估计，特别是在无法获得辐射照射物理测量的情况下。稳定染色体畸变（SCA）或易位已成为辐射照射流行病学研究中应用最广泛的生物剂量学方法，因为它具有很好的辐射剂量-反应曲线特征，并且易位在辐射照射多年后仍可检测到。目的是在未暴露人群中根据年龄、性别、种族和吸烟状况确定染色体易位频率的基线水平。我们联系了美国和国际上的实验室，他们报告了使用FISH的正常人易位频率的数据。收集并分析了1957名未暴露个体的易位数据。确定易位频率与年龄和吸烟状况的关系。光激发发光（OSL）和人类牙釉质用于回顾性剂量估计：REB和合作者正在开发一种替代技术，用于在放射或核事故和恐怖袭击中暴露于电离辐射的个体的体内回顾性辐射剂量估计。该技术是基于人类牙釉质的光刺激发光（OSL）信号。从NIDCR收集了100多颗牙齿，并进行了许多测量，以确定技术的可行性，并确定了几百毫戈瑞的近似检测限。改进的开发正在进行中。放射性核素研究：甲状腺功能亢进患者131I生物动力学数据分析：本研究旨在定量分析1961年之前最初接受放射性碘治疗甲状腺毒症的3000多名患者体内碘-131 （131I）运动的生物动力学数据，这些患者参加了最初的甲状腺毒症随访健康研究（TTFUS）。建立了一个健壮的碘生物动力学模型，并计算了143例甲状腺、碘化物和蛋白结合碘（PBI）患者的生物动力学模型参数和器官剂量系数。外推整个队列的剂量估计。KinDose（动力学数据剂量估计软件）是一种软件工具，用于计算体内放射性生物动力学测量的器官剂量，并使用SAAM II模拟和建模软件对数据进行分析。放射性沉降档案：世界范围内放射性沉降的历史文献和数据库的发展，以改进放射性沉降预测模型。REB和合作者开发了第一个全球放射性尘埃数据的综合数据库，作为一个可访问的研究工具，其中包含从环境测量实验室（EML）获得的全球放射性尘埃沉积数据的扫描和可搜索的历史文件收集。利用这个数据库，REB研究人员正在开发改进的局部和全球沉降物扩散模型，用于预测未来核武器爆炸时的沉降。哈萨克斯坦与接触放射性沉降物有关的甲状腺结节和疾病的研究。原子能机构正在进行一项调查，以估计1949年至1962年期间在哈萨克斯坦塞米巴拉金斯克核试验场（SNTS）进行的地面核试验所产生的放射性沉降物对儿童的内部和外部辐射剂量。剂量测定工作是一项研究的关键组成部分，该研究使用美国/俄罗斯联合剂量测定法、二维蒙特卡罗（2DMC）策略进行不确定剂量估计，以及焦点小组访谈策略收集个人消费率和其他行为的数据，以评估辐射暴露与甲状腺疾病风险之间的关系。马绍尔群岛，剂量和癌症风险评估。根据国会的授权，对在马绍尔群岛进行的核试验的辐射剂量和风险的评估已经完成。此外，还对马绍尔群岛人口中癌症的基线率进行了估计，并完成了预计因辐照而患癌症（甲状腺癌、胃癌、结肠癌、红骨髓癌）的预测。美国人口（包括印第安人）在三位一体核试验中接受的辐射剂量分析。根据国会的授权，对1945年7月在新墨西哥州进行的第一次核试验的剂量和风险进行了部分评估。根据1945年7月在新墨西哥州进行的第一次核试验trinity，对新墨西哥州居民进行了初步剂量计算（全身和甲状腺）。基于网络的辐射剂量和风险计算器。根据美国国家科学院的建议，正在对美国人民因在世界各地进行的核武器试验所产生的放射性沉降物中的碘-131而受到的甲状腺辐射剂量进行估计，包括编制一个基于网络的计算器，用于估计相应的个人甲状腺辐射剂量和相关的甲状腺癌风险。辐射事故后果评估（切尔诺贝利事故）外部暴露研究（清理工人）在切尔诺贝利白血病研究第二阶段的框架内，进行了所有访谈，并重建了所有骨髓剂量。内部暴露研究（公众成员）对二万五千名乌克兰和白俄罗斯人甲状腺癌流行病学研究的分析几乎完成，这些人在切尔诺贝利事故发生时作为儿童受到了暴露。已重新分析了因摄入131I而引起的甲状腺剂量，约占所有照射途径中甲状腺剂量的95%。在乌克兰，已经对不确定性进行了详细评估，其中区分了共有和非共有的组成部分。在白俄罗斯：(1)年龄和地区依赖性甲状腺肿块的评估；(2)事故发生后两个月内在白俄罗斯收集的环境辐射测量数据；（三）评估人体外部和内部污染对甲状腺直接测量用辐射装置读出的信号的贡献；(4)从131I的摄入量估计甲状腺剂量。

Most of the dosimetry work that is carried out at REB has direct or indirect applications to the assessment of radiation doses from bioterrorism events involving environmental radiation. Since 2005, all of the bioterrorism-related studies at REB are funded under an Inter-Agency Agreement between NIAID and NCI. BIODOSIMETRY Analysis of stable chromosome aberrations: Biological monitoring of radiation dose can contribute important, independent estimates of radiation exposure for individuals and populations, especially when physical measurements of radiation exposure are unavailable. Stable chromosome aberrations (SCA) or translocations have been the most widely applied biodosimetry in epidemiologic studies of radiation exposure, because of well-characterized radiation dose-response curves and the persistence of translocations that can be detected many years after radiation exposure. The goal was to establish baseline levels of chromosome translocation frequencies by age, gender, ethnicity and smoking status in unexposed populations. Labratories both in the US and internantionally were contacted that had reported data on translocation frequencies in normal persons using FISH. Translocation data on 1,957 unexposed individuals, were collected and analyzed. Relationships of translocation frequency by age and smoking status were determined. Optically stimulated luminescence (OSL) and human tooth enamel for retrospective dose estimation: REB and collaborators are developing an alternative technique for in vivo retrospective estimation of radiation doses of individuals exposed to ionizing radiation in radiological or nuclear accidents and terrorist attacks. This technique is based on the Optically Stimulated Luminescence (OSL) signal of human dental enamel. More than 100 teeth have been collected from the NIDCR and many measurements made to establish viability of technique and establish approximate limits of detection of a few hundred mGy. Development of refinements are underway. RADIONUCLIDES Radionuclide Studies: Analysis of 131I biokinetic data for hyperthyroid patients: This study is designed to quantitatively analyze biokinetic data on the movement of Iodine-131 (131I) within the human body in more than 3,000 patients who were originally treated with radioactive iodine for thyrotoxicosis prior to 1961, and who were enrolled in the original Thyrotoxicosis Follow-up Health Study (TTFUS). Development of a robust biokinetic model for iodine was completed and the parameters of the biokinetic model and the organ dose coefficients were calculated for the group of 143 patients with iodine measurements in thyroid, iodide, and protein-bound iodine (PBI). Dose estimation was extrapolated for entire cohort. A software tool, KinDose (Kinetic Data Dose Estimation Software) was developed to calculate organ doses from biokinetic measurements of radioactivity in the body when the data are analyzed with the SAAM II simulation and modeling software. RADIOACTIVE FALLOUT Archival of historical documents on worldwide fallout and development of a database to improve fallout prediction models. REB and collaborators develops the first comprehensive database of worldwide fallout data as an accessible research tool containing scanned and searchable historical document collection obtained from the Environmental Measurements Laboratory (EML) for data on fallout deposition worldwide. Using this database REB investigators are developing improved models of local and global fallout dispersion useful for predicting deposition in the event of future nuclear weapons explosions. Study of thyroid nodules and disorders related to exposure to radioactive fallout in Kazakhstan. The REB is conducting an investigation to estimate internal and external radiation dose among persons exposed as children to radioactive fallout from above ground nuclear tests conducted at the Semipalatinsk Nuclear Test Site (SNTS) in Kazakhstan between 1949 and 1962. The dosimetry effort is a critical component of a study evaluating the association between radiation exposure and the risk of thyroid disease using U.S./Russian joint dosimetry methodology, the two-dimensional Monte Carlo (2DMC) strategy for dose estimation with uncertainty, and focus group interview strategy for collection of data on individual consumption rates and other behaviors. Marshall Islands, dose and cancer risk assessment. As mandated by Congress, the assessment of radiation doses and risks from nuclear tests conducted in the Marshall Islands was completed. In addition, an estimation of the baseline rate of cancers among the Marshallese population was made and a projection of cancers (thyroid, stomach, colon, red bone marrow) expected as a result of exposure was completed. An analysis of radiation doses received by the U.S. population including Native Americans by the TRINITY nuclear test.) As mandated by Congress, the assessment of doses and risks from the first nuclear test conducted in New Mexico in July 1945 has been partially conducted. Preliminary dose calculations (whole body and thyroid) have been made for residents of New Mexico from TRININTY ,the first nuclear test,New Mexico in July 1945. Web-based fallout dose and risk calculator. As recommended by the National Academies of Science, the estimation of the thyroid radiation doses received by the American people as a result of I-131 in fallout from nuclear weapons tests conducted worldwide is underway including the preparation of a web-based calculator for estimating the corresponding individual thyroid radiation doses and the related thyroid cancer risk. EVALUATION OF CONSEQUENCES OF RADIATION ACCIDENTS (Chornobyl accident) External exposure study (clean-up workers) Within the framework of the second phase of the Chornobyl leukemia study, all interviews were conducted and all bone-marrow doses were reconstructed. Internal exposure study (members of the public) Analysis is almost completed for the epidemiological studies of thyroid cancer among twenty five thousand Ukrainian and Belarusian individuals who were exposed as children at the time of the Chornobyl accident. The thyroid doses resulting from intakes of 131I, which contribute about 95% of the thyroid dose from all pathways of exposure, have been reanalyzed. In Ukraine, a detailed assessment of the uncertainties, in which shared and unshared components are separated, has been performed. In Belarus: (1) the assessment of the age- and region-dependent thyroid masses; (2) the environmental radiation measurements that were collected in Belarus during the two months following the accident; (3) the assessment of the contribution of external and internal contaminations of the body to the signal read by the radiation devices used for the direct thyroid measurements; and (4) the thyroid dose estimates from intakes of 131I.