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.

• Klíčová slova
• Exposure assessment, Radon-222, Risk assessment, Uranium miners,
• MeSH
• bydlení MeSH
• dospělí MeSH
• hodnocení rizik MeSH
• hornictví * MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádory vyvolané zářením epidemiologie   MeSH
• nemoci z povolání epidemiologie   MeSH
• pracovní expozice * MeSH
• radioaktivní látky znečišťující vzduch * MeSH
• radon * MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• uran * MeSH
• znečištění vzduchu ve vnitřním prostředí MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Francie epidemiologie   MeSH
• Názvy látek
• radioaktivní látky znečišťující vzduch * MeSH
• radon * MeSH
• uran * MeSH

The biologically based two-stage clonal expansion (TSCE) model is used to analyze lung cancer in several miners studies, two new ones (Czech, French) and two historic ones (Chinese, Colorado). In all cases, the model assumptions are identical. An action of radiation on initiation, promotion, and transformation is allowed. While all four studies indicate a highly significant action of radiation on promotion, the action on initiation is not significant in the French cohort, and barely significant in the Colorado miners cohort. No action on transformation is found in the Colorado miners, while the other data sets indicate a borderline significance. The model can describe all the data sets adequately, with different model parameters. The observed patterns in exposure, time since beginning of exposure, birth year, age and calendar year are reproduced well. The doubling exposure rate for initiation is about 3.5 WLM/year in the new data sets, while it is higher in the historic data sets. For transformation the doubling rate is about 20 WLM/year for the new data sets, while again the historic data give higher estimates. The action of radiation on promotion is quite different in the four data sets. These differences also induce different risk estimates at low exposures. The larger power of the new studies at these low exposures, compared to the historic data requires less extrapolation when the risk at very low exposures is estimated.

• MeSH
• algoritmy MeSH
• biologické modely * MeSH
• dávka záření MeSH
• hodnocení rizik metody   MeSH
• hornictví statistika a číselné údaje   MeSH
• incidence MeSH
• kohortové studie MeSH
• lidé MeSH
• monitorování radiace metody   MeSH
• nádory plic mortalita   MeSH
• nádory vyvolané zářením mortalita   MeSH
• obsah radioaktivních látek v organizmu MeSH
• počítačová simulace MeSH
• proporcionální rizikové modely MeSH
• radon analýza   MeSH
• relativní biologická účinnost MeSH
• rizikové faktory MeSH
• věkové rozložení MeSH
• vztah dávky záření a odpovědi MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky kontrolované MeSH
• klinické zkoušky MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• validační studie MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Čína epidemiologie   MeSH
• Colorado epidemiologie   MeSH
• Francie epidemiologie   MeSH
• Názvy látek
• radon MeSH

A two-mutation carcinogenesis model with clonal expansion of pre-malignant cells is used to describe lung cancer mortality data from studies on French and Czech miners with relatively low exposures to radon. The aim was to derive radon-induced lung cancer risk estimates applicable to different populations using a model description consistent with both cellular dose-response relationships, and previous model analyses of animal and human epidemiological data. The significantly different baseline lung cancer risks for the two cohorts that include the effects from the unknown smoking habits, are described with different background model parameters. A uniform description of the effect of radon for both miner cohorts is achieved by applying the same multiplicative effect for radon on the background mutation rates in the model. Incorporating the effects of decreased cellular proliferation at very advanced age improves the description of the baseline lung cancer risk, but does not lead to significant changes in the estimated radiation parameters. Here, a multi-stage model demonstrates the possibility of transferring radon-induced lung cancer risks across populations. The inherent age-time dose-rate relationships in the model allow for extrapolation to lifelong exposures to residential radon concentrations. The resulting cumulated (lifetime) risks from continuous exposure to low-level radon concentrations were found to agree with the results of the BEIR VI models.

• MeSH
• algoritmy MeSH
• analýza přežití MeSH
• biologické modely * MeSH
• dávka záření MeSH
• hodnocení rizik metody   MeSH
• hornictví * MeSH
• incidence MeSH
• kohortové studie MeSH
• lidé MeSH
• monitorování radiace metody   MeSH
• mutační analýza DNA metody   MeSH
• nádory plic mortalita   MeSH
• nádory vyvolané zářením mortalita   MeSH
• obsah radioaktivních látek v organizmu MeSH
• orgánová specificita MeSH
• počítačová simulace MeSH
• radiometrie metody   MeSH
• radon * analýza   MeSH
• relativní biologická účinnost MeSH
• rizikové faktory MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Francie epidemiologie   MeSH
• Názvy látek
• radon * MeSH