Studies of Populations Exposed to Enviromental Sources of Radiation

对核试验或事故中暴露于粉尘的人群的研究是该项目的一个主要重点。乌克兰切尔诺贝利核反应堆事故导致白俄罗斯、乌克兰西北部和与俄罗斯接壤的省份儿童甲状腺癌病例史无前例地增加。在能源部(DOE)和核管理委员会(NRC)的协助下，NCI组织了对白俄罗斯39000名儿童和乌克兰34000名儿童的长期后续研究。到目前为止，大约20,000名受试者的甲状腺已经进行了筛查。在白俄罗斯的一项甲状腺癌病例对照研究中，根据个人剂量估计，甲状腺癌和I-131之间存在统计学上显著的剂量特异性联系。居住在俄罗斯特恰河沿岸的村民暴露于来自马亚克核设施的慢性外部和内部辐射。癌症死亡率正在接受一组约2.8万人的评估，这些人接受了倾倒在河流中的放射性废物的大剂量辐射。目前的工作重点是追踪原始人口以获取重要状况信息；以及利用辐射影响研究剂量估计联合协调委员会进行剂量重建。辐射流行病学处对哈萨克斯坦塞米巴拉金斯克原子弹武器试验场附近严重暴露和轻度暴露的村庄的3000名居民进行了甲状腺筛查研究，这些居民在暴露于放射性尘埃时不到15岁。来自美国和哈萨克斯坦的医生团队通过超声波和针吸活检对甲状腺进行筛查。目前正在努力重建剂量，并将估计的个人剂量与问卷数据和剂量的生物标记联系起来。

Studies of populations exposed to fallout from nuclear tests or accidents are a major focus of this project. The Chernobyl nuclear reactor accident in Ukraine has led to an unprecedented increase in thyroid cancer among children in Belarus, northwestern Ukraine, and bordering Russian provinces. With the assistance of the Department of Energy (DOE) and the Nuclear Regulatory Commission (NRC), NCI has organized long-term follow-up studies of 39,000 children in Belarus and 34,000 in Ukraine. To date, the thyroid glands of approximately 20,000 subjects have been screened. In a case-control study of thyroid cancer in Belarus, with individual dose estimates, a statistically significant dose-specific link between thyroid cancer and I-131 was demonstrated.Villagers living along the banks of the Techa River in Russia were exposed to chronic external and internal radiation from the Mayak nuclear facility. Cancer mortality is being evaluated in a cohort of approximately 28,000 people who received large doses of radiation from the radioactive waste dumped into the river. Current efforts focus on tracing the original population for vital status information; and on dose reconstruction, using the Joint Coordinating Committee for Radiation Effects Research dose estimates. The Radiation Epidemiology Branch conducted a thyroid screening study of 3,000 residents of heavily exposed and lightly exposed villages near the Semipalatinsk Atomic Bomb Weapons Test Site in Kazakstan exposed to radioactive fallout, who were under 15 years of age at exposure. Screening of thyroid glands by ultrasound and needle biopsy was performed by a team of physicians from the U.S. and Kazakstan. Efforts are currently underway for dose reconstruction and to link the estimated individual doses to questionnaire data and biological markers of dose.