Mortality in a combined cohort of uranium enrichment workers

Abstract

Objective To examine the patterns of cause-specific mortality and relationship between internal exposure to uranium and specific causes in a pooled cohort of 29,303 workers employed at three former uranium enrichment facilities in the United States with follow-up through 2011. Methods Cause-specific standardized mortality ratios (SMRs) for the full cohort were calculated with the U.S. population as referent. Internal comparison of the dose-response relation between selected outcomes and estimated organ doses was evaluated using regression models. Results External comparison with the U.S. population showed significantly lower SMRs in most diseases in the pooled cohort. Internal comparison showed positive associations of absorbed organ doses with multiple myeloma, and to a lesser degree with kidney cancer. Conclusion In general, these gaseous diffusion plant workers had significantly lower SMRs than the U.S. population. The internal comparison however, showed associations between internal organ doses and diseases associated with uranium exposure in previous studies.

Circulatory disease in French nuclear fuel cycle workers chronically exposed to uranium: a nested case–control study

“…Most of latter studies reported ERR of 10% per gray. Nevertheless, it should be noted that several previous α-radiation low-dose radiation studies obtained similarly elevated risk estimates in the analyses of lung cancer mortality and internal lung dose due to uranium: French uranium miners (ERR/Gy 503.2, 95% CI 121.5 to 1225.0),41 US Fernald Feed Materials Production Centre (ERR/Gy 22, 95% CI −9.3 to 70)42 and US uranium enrichment workers (ERR/Gy −750, 95% CI −2310 to 1120) 43. These high estimates may indicate a difficulty in extrapolating risk above the doses concentrated in a very low dose range and prove a necessity for future combined studies to gain in statistical power.…”

Dose‐response relationships between internally‐deposited uranium and select health outcomes in gaseous diffusion plant workers, 1948‐2011

“…The details on the cohort and case ascertainment were described previously . Briefly, the study subjects included a pooled cohort of workers from three uranium enrichment facilities: K‐25, PORTS, and PGDP.…”

“…Operations at fuel cycle facilities present a potential for worker exposures to various uranium compounds that are known or suspected to cause adverse human health effects. Yiin et al examined the patterns of cause‐specific mortality in a combined cohort of 29 303 workers from three gaseous diffusion plants (GDP) in the United States: the Oak Ridge Gaseous Diffusion Plant (also known as K‐25) in Oak Ridge, Tennessee (TN), the Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio (OH), and the Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky (KY). Although workers at these former uranium enrichment facilities had significantly lower standardized mortality ratios (SMRs) for most diseases than the U.S. population, excess SMRs that were not statistically significant were observed in kidney cancer, bone cancer, non‐Hodgkin's lymphoma (NHL), and chronic renal diseases.…”

“…This aim of the current study was a more in‐depth examination of the dose‐response relationships found for these health outcomes in the previously assembled cohort of uranium enrichment workers by including estimated doses to the kidney, bone surface, and red bone marrow from contaminant radionuclides plutonium‐239 ( 239 Pu) and technetium ( 99 Tc) in recycled uranium as potential confounders. This current study also includes evaluation of linear‐quadratic and restricted cubic splines regression models in addition to the linear excess relative risk (ERR) model reported in the previous study . The clarification of the relationship between kidney and red bone marrow dose from occupational exposure to uranium and health risk will aid in evaluating current levels of protection and ultimately reduce cancer mortality for workers in the uranium fuel cycle.…”

Internal dose assessment for the French cohort of uranium workers

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Recently, several epidemiological studies [1][2][3][4][5][6][7][8][9][10][11][12][13][14] were dedicated to identifying potential health effects from incorporated radionuclides. To do so, the exposure and/or dose of individuals were quantified and associations with health status investigated.

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