Indoor radon exposure and lung cancer in Belgium

Indoor radon is the most important source of ionising radiation for the general public and is estimated to be a causal factor for lung cancer. Most risk assessment for low doses are based upon extrapolations of the observations among high exposed groups. As the validity of such procedure is still a controversal matter and in order to obtain direct epidemiological evidence, a case-control study about radon and lung cancer was set-up in southern Belgium. All subjects are recruited at the department of pneumology of the clinic of the catholic university of Louvain at Mont Godinne. In the first year some 130 persons entered the study. Preliminary analysis of the data gives an odds ratio of 4.2 for the exposed group of male smoking cases compared to the matched non exposed control group.