Exposure to residential radon and lung cancer in never-smokers: the preliminary results of the LCRINS study.

INTRODUCTION AND OBJECTIVE Residential radon is the second most important risk factor for lung cancer and the first among never-smokers. The objective of this study is to report the concentrations of residential radon in a series of never-smoker cases recruited in a multicenter study of cases and controls in northwestern Spain. In this study, all the hospitals in the Spanish province of Galicia and one from Asturias participated. PATIENTS AND METHODS The present article includes a series of cases with residential radon measurements. All the subjects were personally interviewed, 3 ml of blood were taken from each, and they were each given instructions about how to place a residential radon detector in their homes. RESULTS Sixty-nine case subjects were recruited, 84% of whom were women with a mean age of 71, and 81% of whom had adenocarcinoma. The average concentration of residential radon in the cases was 237 Bq/m(3), while the average concentration in the Galician population is 79 Bq/m(3). No relationship was observed between the concentration of residential radon and either sex or age at the time of diagnosis of the cases, but there was a tendency towards having a greater concentration in those diagnosed with small-cell and large-cell carcinoma. CONCLUSIONS The concentrations of residential radon in the cases included are very high at about three times the average concentration of residential radon to which the general population of Galicia is exposed.