Division of Cancer Epidemiology & Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD.
Retired (NCI/NIH).
Health Phys. 2020 Oct;119(4):478-493. doi: 10.1097/HP.0000000000001333.
The Trinity nuclear test, conducted in 1945, exposed residents of New Mexico to varying degrees of radioactive fallout. Companion papers in this issue have detailed the results of a dose reconstruction that has estimated tissue-specific radiation absorbed doses to residents of New Mexico from internal and external exposure to radioactive fallout in the first year following the Trinity test when more than 90% of the lifetime dose was received. Estimated radiation doses depended on geographic location, race/ethnicity, and age at the time of the test. Here, these doses were applied to sex- and organ-specific risk coefficients (without applying a dose and dose rate effectiveness factor to extrapolate from a population with high-dose/high-dose rates to those with low-dose/low-dose rates) and combined with baseline cancer rates and published life tables to estimate and project the range of radiation-related excess cancers among 581,489 potentially exposed residents of New Mexico. The total lifetime baseline number of all solid cancers [excluding thyroid and non-melanoma skin cancer (NMSC)] was estimated to be 183,000 from 1945 to 2034. Estimates of ranges of numbers of radiation-related excess cancers and corresponding attributable fractions from 1945 to 2034 incorporate various sources of uncertainty. We estimated 90% uncertainty intervals (UIs) of excess cancer cases to be 210 to 460 for all solid cancers (except thyroid cancer and NMSC), 80 to 530 for thyroid cancer, and up to 10 for leukemia (except chronic lymphocytic leukemia), with corresponding attributable fractions ranging from 0.12% to 0.25%, 3.6% to 20%, and 0.02% to 0.31%, respectively. In the counties of Guadalupe, Lincoln, San Miguel, Socorro, and Torrance, which received the greatest fallout deposition, the 90% UI for the projected fraction of thyroid cancers attributable to radioactive fallout from the Trinity test was estimated to be from 17% to 58%. Attributable fractions for cancer types varied by race/ethnicity, but 90% UIs overlapped for all race/ethnicity groups for each cancer grouping. Thus, most cancers that have occurred or will occur among persons exposed to Trinity fallout are likely to be cancers unrelated to exposures from the Trinity nuclear test. While these ranges are based on the most detailed dose reconstruction to date and rely largely on methods previously established through scientific committee agreement, challenges inherent in the dose estimation, and assumptions relied upon both in the risk projection and incorporation of uncertainty are important limitations in quantifying the range of radiation-related excess cancer risk.
三位一体核试验于 1945 年进行，使新墨西哥州的居民受到不同程度的放射性沉降物的影响。本期的配套论文详细介绍了一项剂量重建的结果，该剂量重建估计了 1945 年三位一体试验后第一年从内照射和外照射到新墨西哥州居民的放射性沉降物中吸收的组织特异性辐射剂量，当时 90%以上的终身剂量已被吸收。估计的辐射剂量取决于地理位置、种族/民族以及试验时的年龄。在这里，这些剂量被应用于按性别和器官特异性风险系数（不应用剂量和剂量率效应系数将高剂量/高剂量率人群外推至低剂量/低剂量率人群），并结合基线癌症率和已发表的生命表，以估计和预测 581489 名潜在暴露于新墨西哥州的居民中与辐射相关的过量癌症的范围。从 1945 年到 2034 年，所有实体癌（不包括甲状腺癌和非黑色素瘤皮肤癌（NMSC））的终身基线总数预计为 183000 例。1945 年至 2034 年，辐射相关过量癌症数量和相应归因分数的估计范围纳入了各种不确定性来源。我们估计，所有实体癌（不包括甲状腺癌和 NMSC）的过量癌症病例 90%置信区间（UI）为 210 至 460，甲状腺癌为 80 至 530，白血病（除慢性淋巴细胞白血病外）为 10，相应的归因分数范围为 0.12%至 0.25%、3.6%至 20%和 0.02%至 0.31%。在接收放射性沉降物最多的瓜达卢佩、林肯、圣米格尔、索科罗和托兰斯县，估计归因于三位一体试验放射性沉降物的甲状腺癌预计占比的 90%UI 为 17%至 58%。癌症类型的归因分数因种族/民族而异，但对于每个癌症分组，所有种族/民族群体的 90%UI 都重叠。因此，在接触三位一体放射性沉降物的人中发生或将要发生的大多数癌症可能与三位一体核试验的辐射暴露无关。虽然这些范围基于迄今为止最详细的剂量重建，并在很大程度上依赖于科学委员会协议先前确立的方法，但剂量估计中固有的挑战以及风险预测和不确定性纳入中所依赖的假设，都是在量化与辐射相关的过量癌症风险范围方面的重要限制。
