Studies of Populations Exposed to Occupational Sources o

美国放射技术人员队列中的癌症和其他死亡风险 1982年，放射流行病学分支（REB）与明尼苏达大学合作，在146,022名美国人中开展了一项全国范围的癌症发病率和死亡率队列研究。S.放射技术人员。该队列中73%为女性，这为研究长期低至中等剂量辐射照射对乳腺癌和甲状腺癌的影响提供了难得的机会，这两个部位是妇女辐射致癌的两个最敏感器官。其他癌症和非癌症严重疾病的结果也正在评估与长期低至中等剂量暴露的关系。2001年以来的主要研究结果包括：1950年以前，随着工作年限的增加，乳腺癌的死亡风险显著增加; 1950年以前，随着工作年限的增加，脑血管病的死亡风险显著增加;与SEER相比，发现乳腺癌（女性）、甲状腺癌和黑色素瘤的发病风险显著升高，并对无应答进行了调整。内部队列分析显示，与1940年以前工作相关的乳腺癌发病风险显著升高，与1950年以前工作相关的黑色素瘤和非黑色素瘤皮肤癌发病风险显著升高，与1950年以前工作>5年相关的非慢性淋巴细胞白血病发病风险适度升高，以及与1960年以前工作相关的甲状腺癌发病风险升高。而与肺癌没有关联。ATM基因的突变分析显示，这些基因的突变不太可能占遗传性乳腺癌的很大比例，但一些低频多态性可能增加乳腺癌的风险;一级亲属中乳腺癌的亲属队列分析发现，先证者的HER 2变异状态与非显著性风险升高相关，与XRCC 1 194和BRIP 1 919变异体相关的风险显著增加，与APEX 148和BRCA 2 372变异体相关的风险显著降低。在过去一年中，在重建历史剂量方面取得了进展，目前正在进行这项工作，以提供1916年至2005年期间每名技术人员每年工作的年度和累积职业徽章剂量（个人剂量当量）估计数，以及器官和组织吸收剂量，包括骨髓、女性乳腺、甲状腺、卵巢、睾丸、肺和皮肤。年剂量被定义为密度分布，以考虑估计值中的不确定性。在过去的一年中，进行了第三次后续调查，扩大了遗传研究，并对剂量评估进行了进一步的改进。 接触钚和长期外辐射的俄罗斯核工作人员的癌症死亡率 目前正在对一组26 000名Mayak核设施工人（在俄罗斯联邦）进行研究，因为他们是长期受到高剂量外部辐射和钚照射的独特职业群体。对于白血病、肺癌、肝癌和骨癌（作为单一类别进行分析）以及肺癌、骨癌和肝癌以外的所有实体癌的死亡率，证明了外部辐射照射的剂量-反应关系。按性别、接触时的年龄和接触后的时间划分的风险模式与在原子弹幸存者中观察到的风险模式大致相似。死亡率分析还清楚地表明，体内接触钚会导致肺癌、肝癌和骨癌的过度风险，这些部位受到钚的最高剂量。最近进行的肺癌死亡率的剂量反应分析表明，钚对肺的内部剂量和外部剂量有显著的相关性（p < 0.001）。

Cancer and Other Mortality Risks in a Cohort of U.S. Radiologic Technologists In 1982, the Radiation Epidemiology Branch (REB), in collaboration with the University of Minnesota, initiated a nationwide cohort study of cancer incidence and mortality among 146,022 U. S. radiologic technologists. The cohort is 73% female, offering a rare opportunity to study effects of protracted low- to moderate-dose radiation exposure on breast and thyroid cancer, the two most sensitive organ sites for radiation carcinogenesis in women. Other cancer and non-cancer serious disease outcomes are also being evaluated in relation to protracted low-to-moderate dose exposures. Major findings since 2001 include: Mortality risks for breast cancer increased significantly with increasing number of years worked before 1950; mortality from cerebrovascular diseases increased significantly with earlier year first worked and with number of years worked before 1950; significantly elevated risks were found for incident cancers of the breast (female), thyroid, and melanoma compared to SEER and adjusted for non-response. Internal cohort analyses revealed significantly elevated incidence risks for breast cancer associated with working before 1940, melanoma and non-melanoma skin cancers related to working before 1950, modest elevated risk for non-chronic lymphocytic leukemia related to working >5 years before 1950, and a suggested elevated risk for thyroid cancer with working before 1960, while no associations were found for lung cancer. Mutational analysis of the ATM genes revealed that mutations in these genes are unlikely to account for a significant fraction of inherited breast cancer but a few low-frequency polymorphisms may increase breast cancer risk; kin-cohort analyses of breast cancer among first-degree relatives found a non-significant elevated risk associated with HER2 variant status of probands, significantly increased risks associated with XRCC1 194 and BRIP1 919 variants, and significantly reduced risks associated with APEX 148 and BRCA2 372 variants. During the past year, progress was made on historical dose reconstruction, which is being undertaken to provide estimates of annual and cumulative occupational badge doses (personal dose equivalent) for each technologist for each year worked from 1916 through 2005, as well as absorbed doses to organs and tissues including bone-marrow, female breast, thyroid, ovary, testes, lung and skin. The annual doses are defined as density distributions to account for uncertainties in the estimates. During the past year, a third follow-up survey was conducted, the genetic studies were expanded, and additional refinements were made to the dose assessment. Cancer Mortality in Russian Nuclear Workers Exposed to Plutonium and Protracted External Radiation A cohort of 26,000 Mayak nuclear facility workers (in the Russian Federation) is being studied because they comprise a unique occupational group for protracted exposure to external radiation at high doses and exposure to plutonium. Dose-response relationships for exposure to external radiation were demonstrated for mortality from leukemia; cancers of the lung, liver and bone (analyzed as a single category); and all solid cancers other than lung, bone and liver cancer. Patterns of risk by sex, age at exposure and time since exposure were generally similar to those observed in A-bomb survivors. Mortality analyses have also clearly demonstrated that internal exposure to plutonium results in excess risks for cancers of the lung, liver and bone cancers, the sites receiving the highest doses from plutonium. Recently conducted dose-response analyses of lung cancer mortality indicated significant associations for both internal dose to the lung from plutonium and external dose (p < 0.001).