RESIDENTIAL RN-222 EXPOSURE AND LUNG-CANCER - EXPOSURE ASSESSMENT METHODOLOGY

Although occupational epidemiological studies and animal experimentati on provide strong evidence that radon-222 (Rn-222) progeny exposure ca uses lung cancer, residential epidemiological studies have not confirm ed this association. Past residential epidemiological studies have yie lded contradictory findings. Exposure misclassification has seriously compromised the ability of these studies to detect whether an associat ion exists between Rn-222, exposure and lung cancer. Misclassification of Rn-222 exposure has arisen primarily from. I) detector measurement error; 2) failure to consider temporal and spatial (222)R, variations within a home; 3) missing data from previously occupied homes that cu rrently are inaccessible; 4) failure to link Rn-222 concentrations wit h subject mobility; and 5) measuring Rn-222 gas concentration as a sur rogate for Rn-222 progeny exposure. This paper examines these methodol ogical dosimetry problems and addresses how we are accounting for them in an ongoing, population-based, case-control study of Rn-222 and lun g cancer in Iowa.