The estimation of the thyroid doses received in Belarus after the Chernobyl accident is based on the analysis of exposure-rate measurements performed with radiation detectors placed against the necks of about 130,000 residents. The purpose of these measurements was to estimate the 131I activity contents of the thyroids of the subjects. However, because the radiation detectors were not equipped with collimators and because the subjects usually wore contaminated clothes, among other factors, the radiation signal included, in addition to the gamma rays emitted during the decay of the 131I activity present in the thyroid, contributions from external contamination of the skin and clothes and internal contamination of organs other than the thyroid by various radionuclides. The assessment of the contributions of the external and internal contamination of the body to the radiation signal is divided into two parts: (1) the estimation of the radionuclide activities deposited on, and incorporated in, various parts of the body, and (2) the responses of the radiation detectors to the gamma rays emitted by the radionuclides deposited on, and incorporated in, various parts of the body. The first part, which is presented in this paper, includes a variety of exposure scenarios, models, and calculations for 17 of the most abundant gamma-emitting radionuclides contributing to the thyroid detector signal, while the second part is presented in a companion paper. The results presented in the two papers were combined to calculate the contributions of the external and internal contamination of the body to the radiation signal, and, in turn, the 131I activities in the thyroids of all subjects of an epidemiologic study of thyroid cancer and other thyroid diseases among 11,732 Belarusian-American cohort members who were exposed in childhood and adolescence.

中文翻译：

---

切尔诺贝利事故后在白俄罗斯进行的甲状腺131I测量结果对身体和衣服的外部和内部放射性污染的影响。第 1 部分：外部和内部放射性污染的估计。


对切​​尔诺贝利事故后白俄罗斯接受的甲状腺剂量的估计是基于对放置在约 130,000 名居民颈部的辐射探测器进行的暴露率测量的分析。这些测量的目的是估计受试者甲状腺的 131I 活性含量。然而，由于辐射探测器没有配备准直器，而且受试者通常穿着受污染的衣服，除其他因素外，辐射信号除了甲状腺中 131I 活性衰变期间发出的伽马射线外，还包括来自各种放射性核素对皮肤和衣服的外部污染以及除甲状腺以外的器官的内部污染。身体外部和内部污染对辐射信号的贡献的评估分为两个部分：(1) 沉积在身体各个部位和融入身体各个部位的放射性核素活度的估计，以及 (2)辐射探测器对沉积在身体各部位或融入身体各部位的放射性核素发射的伽马射线的响应。本文介绍的第一部分包括对甲状腺探测器信号有贡献的 17 种最丰富的伽马发射放射性核素的各种暴露场景、模型和计算，而第二部分则在另一篇论文中介绍。 两篇论文中提出的结果相结合，计算了身体外部和内部污染对辐射信号的贡献，进而计算了甲状腺癌和其他疾病流行病学研究中所有受试者甲状腺中的 131I 活性。 11,732 名白俄罗斯裔美国人队列成员在童年和青少年时期暴露于甲状腺疾病。