Epidemiological evidence of lung cancer risk from radon is based mainly on studies of underground miners where occupational exposures were, historically, relatively high in comparison to residential indoor exposure. However, radiation protection measures have caused radon levels in uranium mines to decrease significantly in more recent periods. Miners' occupational exposure is limited to their working years while they are exposed to environmental radon at home over their entire lifetime. Even during their limited working years, workers spend much more time at home than in workplaces. The biological effect of radon in mines cannot be distinguished from the biological effect of residential radon. Therefore, for an exposure-risk relationship study of former uranium miners, excess radon-induced lung cancer cases should be related to the combined radon exposure cumulated in workplaces and at homes in excess of the radon exposure of the reference population. This is especially important when residential radon levels differ or vary significantly between miners and the reference population over the course of extended follow-up years. This paper reviews some recent studies on former uranium miners, shares what seems controversial to the author and wonders whether lifetime exposure at home to widely varying radon concentrations can actually impact the quality of exposure assessment, and hence impact the results of the exposure-risk relationship.

• Keywords
• Exposure assessment, Radon-222, Risk assessment, Uranium miners,
• MeSH
• Housing MeSH
• Adult MeSH
• Risk Assessment MeSH
• Mining * MeSH
• Middle Aged MeSH
• Humans MeSH
• Neoplasms, Radiation-Induced epidemiology   MeSH
• Occupational Diseases epidemiology   MeSH
• Occupational Exposure * MeSH
• Air Pollutants, Radioactive * MeSH
• Radon * MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Uranium * MeSH
• Air Pollution, Indoor MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Czech Republic epidemiology   MeSH
• France epidemiology   MeSH
• Names of Substances
• Air Pollutants, Radioactive * MeSH
• Radon * MeSH
• Uranium * MeSH

The aim of the present study was to evaluate the risk of lung cancer from combined exposure to radon and smoking. Methodologically, it is based on case-control studies nested within two Czech cohort studies of nearly 11,000 miners followed-up for mortality in 1952-2010 and nearly 12,000 inhabitants exposed to high levels of radon in homes, with mortality follow-up in 1960-2010. In addition to recorded radon exposure, these studies use information on smoking collected from the subjects or their relatives. A total of 1,029 and 370 cases with smoking information have been observed in the occupational and environmental (residential) studies, respectively. Three or four control subjects have been individually matched to cases according to sex, year of birth, and age. The combined effect from radon and smoking is analyzed in terms of geometric mixture models of which the additive and multiplicative models are special cases. The resulting models are relatively close to the additive interaction (mixing parameter 0.2 and 0.3 in the occupational and residential studies, respectively). The impact of the resulting model in the residential radon study is illustrated by estimates of lifetime risk in hypothetical populations of smokers and non-smokers. In comparison to the multiplicative risk model, the lifetime risk from the best geometric mixture model is considerably higher, particularly in the non-smoking population.

• MeSH
• Mining MeSH
• Smoking adverse effects   MeSH
• Humans MeSH
• Lung Neoplasms epidemiology   etiology   MeSH
• Air Pollutants, Radioactive adverse effects   MeSH
• Radon adverse effects   MeSH
• Risk MeSH
• Case-Control Studies MeSH
• Uranium MeSH
• Environmental Exposure adverse effects   analysis   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic epidemiology   MeSH
• Names of Substances
• Air Pollutants, Radioactive MeSH
• Radon MeSH
• Uranium MeSH