Analysis of mortality in a pooled cohort of Canadian and German uranium processing workers with no mining experience

Abstract

PurposeLong-term health risks of occupational exposures to uranium processing were examined to better understand potential differences with uranium underground miners and nuclear reactor workers.MethodsA cohort study of mortality of workers from Port Hope, Canada (1950–1999) and Wismut, Germany (1946–2008) employed in uranium milling, refining, and processing was conducted. Poisson regression was used to evaluate the association between cumulative exposures to radon decay products (RDP) and gamma-rays and causes of death potentially related to uranium processing.ResultsThe pooled cohort included 7431 workers (270,201 person-years of follow-up). Mean RDP exposures were lower than in miners while gamma-ray doses were higher than in reactor workers. Both exposures were highly correlated (weighted rho = 0.81). Radiation risks of lung cancer and cardiovascular diseases (CVD) in males were increased but not statistically significant and compatible with risks estimated for miners and reactor workers, respectively. Higher RDP-associated CVD risks were observed for exposures 5–14 years prior to diagnosis compared to later exposures and among those employed <5 years. Radiation risks of solid cancers excluding lung cancer were increased, but not statistically significant, both for males and females, while all other causes of death were not associated with exposures.ConclusionsIn the largest study of uranium processing workers to systematically examine radiation risks of multiple outcomes from RDP exposures and gamma-rays, estimated radiation risks were compatible with risks reported for uranium miners and nuclear reactor workers. Continued follow-up and pooling with other cohorts of uranium processing workers are necessary for future comparisons with other workers of the nuclear fuel cycle.Electronic supplementary materialThe online version of this article (doi:10.1007/s00420-017-1260-9) contains supplementary material, which is available to authorized users.

Radiation databases and archives – examples and comparisons

“…Studies so far have shown that there is a significant relationship between cumulative radon exposures and extrapulmonary cancers, but the significance is lost when accounting for possible confounding factors such as arsenic or dust exposure (Kreuzer et al 2008). There are also pooled analyses being done for the risks of radon exposure from miners in different countries (Leuraud et al 2011;Zablotska et al 2018). This type of meta-analysis is feasible because the Wismut Cohort data is open to the public by request.…”

Cohort profile: four early uranium processing facilities in the US and Canada

“…uranium enrichment workers), and they should be carefully evaluated in separate studies. To date, only a few studies have conducted dose-response analyses of uranium processing workers with individual radiation doses (Dupree-Ellis et al 2000;Guseva Canu et al 2010;Silver et al 2013;Zablotska et al 2013;Gillies and Haylock 2014;Kreuzer et al 2015;Zablotska et al 2018;Zhivin et al 2018;Golden et al 2019). A limited number of these studies estimated individual doses from uranium or other radionuclides (Silver et al 2013;Kreuzer et al 2015;Zhivin et al 2018;Golden et al 2019), and study findings were constrained by relatively small sample sizes.…”

Comparative proteomic analysis in serum of former uranium miners with and without radon induced squamous lung cancer

“…Uranium minerals are associated with radioactive elements such as radium and radon in the ore which arise from the radioactive decay [ 1 ]. Radium decay due to emitted high-LET alpha-radiation has been found to be carcinogenic to humans [ 2 ].…”

“…Uranium underground miners are primarily exposed to internal ionizing radiation from radon decay products especially α-emitters such as 222 Rn, 218 Po, 214 Pb, 214 Bi and 214 Po and also to dust with high contents of crystalline silica via inhalation [ 3 ]. To a lesser extent, they are also exposed to uranium ore dust and to external ɣ-rays, both of which are important to consider for risk to organs other than lungs [ 1 ]. Uranium mining and processing with a total yield of 231,000 tones of Uranium took place by the Wismut Company, East Germany between the years 1946 and 1990.…”