Mortality from cancer and non-cancer diseases in the Lithuanian cohort of Chernobyl cleanup workers (2001–2020)

Abstract

We examined the mortality risk from cancer and non-cancer diseases from 2001 to 2020 among Lithuanian Chernobyl cleanup workers exposed to ionizing radiation while working in areas contaminated by the Chernobyl nuclear power plant (NPP) accident. The mortality risk was estimated by calculating the standardized mortality ratio (SMR) with a 95% confidence interval (CI). A total of 1922 deaths were registered among the 5562 traced men. The all-cause mortality was slightly elevated (SMR = 1.07, 95% CI, 1.03–1.12), as was the mortality from all malignant neoplasms (SMR 1.15, 95% CI, 1.06–1.26), with the highest risk observed for smoking-related cancers (SMR 2.70, 95% CI, 2.44–2.99). The SMR for all circulatory diseases was also a little higher compared with the general Lithuanian male population (SMR 1.09, 95% CI, 1.02–1.18), particularly for cerebrovascular diseases (SMR 1.46, 95% CI, 1.22–1.74). For diseases of the circulatory system and all malignant neoplasms, the mortality risks were similar in both groups of documented external radiation doses (<100 and ≥100 mSv). The only exception pertains to hypertensive disease, where the SMR was higher in the dose group exceeding 100 mSv, compared with the dose group of ≤100 mSv (SMR 1.68, 95% CI, 1.03–2.74 vs. 1.4, 95% CI, 0.84–2.32, respectively). Continuing follow-up of mortality patterns of cancer and non-cancer diseases within the cohorts of Chernobyl cleanup workers provides important information about the long-term impact of the Chernobyl accident on health.