The planned Brazilian indoor radon survey--concepts and particular challenges.

Similar to the tendency in Europe and North America, awareness towards environmental hazards to health has been rising strongly in Brazil for some years. Among these, indoor radon (Rn) is increasingly being acknowledged as an indoor pollutant that contributes to lung cancer and which one therefore attempts to limit by regulations. Scattered regional surveys performed in Brazil have shown that Rn problem may exist in certain regions, but not much is known about its possible overall extent. Therefore, the idea of a national survey has been brought forward. It is still in the conceptual phase; in this contribution, the authors present the state of knowledge and addressing of particular challenges that can be expected to be encountered.