Radiation Effects on Mortality from Solid Cancers Other than Lung, Liver, and Bone Cancer in the Mayak Worker Cohort: 1948–2008

Abstract

Radiation effects on mortality from solid cancers other than lung, liver, and bone cancer in the Mayak worker cohort: 1948–2008. The cohort of Mayak Production Association (PA) workers in Russia offers a unique opportunity to study the effects of prolonged low dose rate external gamma exposures and exposure to plutonium in a working age population. We examined radiation effects on the risk of mortality from solid cancers excluding sites of primary plutonium deposition (lung, liver, and bone surface) among 25,757 workers who were first employed in 1948–1982. During the period 1948–2008, there were 1,825 deaths from cancers other than lung, liver and bone. Using colon dose as a representative external dose, a linear dose response model described the data well. The excess relative risk per Gray for external gamma exposure was 0.16 (95% CI: 0.07 – 0.26) when unadjusted for plutonium exposure and 0.12 (95% CI 0.03 – 0.21) when adjusted for plutonium dose and monitoring status. There was no significant effect modification by sex or attained age. Plutonium exposure was not significantly associated with the group of cancers analyzed after adjusting for monitoring status. Site-specific risks were uncertainly estimated but positive for 13 of the 15 sites evaluated with a statistically significant estimate only for esophageal cancer. Comparison with estimates based on the acute exposures in atomic bomb survivors suggests that the excess relative risk per Gray for prolonged external exposure in Mayak workers may be lower than that for acute exposure but, given the uncertainties, the possibility of equal effects cannot be dismissed.

Breast cancer risk and protracted low-to-moderate dose occupational radiation exposure in the US Radiologic Technologists Cohort, 1983–2008

“…The difference in the ERRs for Japanese and western women appeared to be largely due to marked differences in the baseline rates in Japan from those in western countries. The latest incidence ERR estimate in the cohort of Russian women who received chronic low-dose-rate environmental exposures (Davis et al , 2015) is only slightly higher than that seen in this study, whereas the breast cancer mortality ERR in the Mayak plutonium production workers (Sokolnikov et al , 2015) was somewhat lower than our USRT estimate.…”

“…The estimate corresponds to the ERR at attained age 50 years.dFrom Davis et al (2015).eFrom Sokolnikov et al (2015).…”

Biological Effectiveness of Ionizing Radiation: Acute vs. Protracted Exposures

“…In the author's opinion, the dose-effect relationships with non-neoplastic diseases [30][31][32][33][34] call in question such relationships with cancer, reported e.g. in the studies [23,24,[35][36][37][38][39][40][41][42][43] including those cited in [2,25] in support of the DDREF lowering. Although there may be some risk of cardiovascular disease at high dose and dose-rate exposures [16], existing data are insufficient to confirm a cause-effect relationship between radiation and cardiovascular diseases at doses below 1-2 Gy, while plausible biological mechanisms are unknown [44].…”

Correction of confidence intervals in excess relative risk models using Monte Carlo dosimetry systems with shared errors

“…Support for the study of this cohort is currently provided by the Russian Ministry of Health and (through a bi-national cooperative agreement between Russia and the United States) from the U.S. Department of Energy. As currently defined, the cohort includes 25,757 people who began work at one of the main plants (reactor complex, radiochemical plant, or plutonium production plant) or in one of two auxiliary departments (water treatment or mechanical repair) between 1948 and 1982 [22]. About 25% of the cohort members are women.…”