Radon in indoor spaces: an underestimated risk factor for lung cancer in environmental medicine

Occupational medicine has long recognized radon to be a cause of lung cancer, especially among miners working under ground. Until recently, however, little scientific evidence was available about the risk to the general population caused by indoor radon.

The authors analyzed literature that they found by a selective search in the light of the recently published S1 guideline of the German Society of Occupational and Environmental Medicine (Deutsche Gesellschaft für Arbeitsmedizin und Umweltmedizin) and a recent publication of the German Commission on Radiological Protection (Strahlenschutzkommission).

Exposure to indoor radon and its decay products is a major contributor to the radiation exposure of the general population. In Germany, the mean radiation exposure due to radon in living rooms and bedrooms is about 49 Bq/m(3). It is well documented in the scientific literature that indoor radon significantly increases the risk of lung cancer, probably in a linear dose-response relationship with no threshold. Every 100 Bq/m(3) increase in the radon concentration is estimated to increase the relative risk for lung cancer by 8% to 16%. After cigarette smoking, radon is the second main cause of lung cancer in the general population without occupational exposure.

From the point of view of preventive environmental medicine, it is important to identify buildings with high radon concentrations, initiate appropriate measures, and minimize radon exposure, particularly in new buildings.