Correlation between Rn exposure and 210Po activity in Yugoslavian rural communities

Abstract

Background: In epidemiological studies investigating radon-related health risk, the radon exposures are often derived from contemporary short-term radon measurements. Recent radon measurements, taken over a period of 1 year in dwellings, are often casually extrapolated and taken to be representative for periods spanning several decades. By simply considering the well-known variability of radon concentrations in dwellings and its sensibility to trivial factors such as living habits or minor changes in the dwelling itself, an amount of skepticism concerning the reliability of this practice should arise. In mining areas, this variability is already well acknowledged since mining conditions, such as ventilation of mine shafts, flooding of mine galleries, etc., are known to be able to change radon concentrations in dwellings built on top of mine shafts for over more than one decade. Methods: This study was conducted in stable rural communities in Yugoslavia. Present radon concentrations were compared to an indicator of past radon concentrations, that is the 210Po activity, fixed on glass surfaces or in the bulk of voluminous materials. Results: In less than 50% of the cases, the past and present radon concentrations agree within a factor of 2. Conclusions: This comparison indicates that even in stable rural communities, deriving past radon concentrations by extrapolating present ones is not a particularly good practice.