Data from the German
uranium miners cohort study were analyzed to investigate the
radon-related risk of mortality from
cancer and
cardiovascular diseases. The Wismut cohort includes 58,987 men who were employed for at least 6 months from 1946 to 1989 at the former Wismut
uranium mining company in Eastern Germany. By the end of 2003, a total of 3,016
lung cancer deaths, 3,355 deaths from extrapulmonary
cancers, 5,141 deaths from
heart diseases and 1,742 deaths from
cerebrovascular diseases were observed. Although a number of studies have already been published on various endpoints in the Wismut cohort, the aim of the present analyses is to provide a direct comparison of the magnitude of
radon-related risk for different
cancer sites and
cardiovascular diseases using the same data set, the same follow-up period and the same statistical methods. A specific focus on a group of
cancers of the extrathoracic airways is also made here, due to the assumed high organ doses from absorbed
radon progeny. Internal Poisson regression was used to estimate the excess relative risk (ERR) per unit of cumulative exposure to
radon in working level months (WLM) and its 95% confidence limits (CI). There was a statistically significant increase in the risk of
lung cancer with increasing
radon exposure (ERR/WLM = 0.19%; 95% CI: 0.17%; 0.22%). A smaller, but also statistically significant excess was found for
cancers of the extrathoracic airways and trachea (ERR/WLM = 0.062%; 95% CI: 0.002%; 0.121%). Most of the remaining nonrespiratory
cancer sites showed a positive relationship with increasing
radon exposure, which, however, did not reach statistical significance. No increase in risk was noted for
coronary heart diseases (ERR/WLM = 0.0003%) and
cerebrovascular diseases (ERR/WLM = 0.001%). The present data provide clear evidence of an increased
radon-related risk of death from
lung cancer, some evidence for an increased
radon-related risk of death from
cancers of the extrathoracic airways and some other extrapulmonary
cancers, and no evidence for mortality from
cardiovascular diseases. These findings are consistent with the results of other miner studies and dosimetric calculations for
radon-related organ doses.