CASE-CONTROL STUDY OF RESIDENTIAL RADON AND LUNG-CANCER IN WINNIPEG, MANITOBA, CANADA

A case-control study of lung cancer in relation to exposure to radon i n homes in Winnipeg, Manitoba, Canada, was conducted during 1983-1990. In total, 738 individuals with histologically confirmed incident case s of lung cancer were interviewed, along with 738 controls matched on age (+/- 5 years) and sex. Radon dosimeters were placed in all residen ces in which the study subjects had reported living within the Winnipe g metropolitan area for at least 1 year. Radon dosimetry was done by m eans of integrated alpha-track measurements over a 1-year period. In t he homes monitored, the average level of radon-222 was about 120 becqu erels (Bq)/m(3) in the bedroom area and 200 Bq/m(3) in the basement. A fter adjusting for cigarette smoking and education, no increase in the relative risk for any of the histologic types of lung cancer observed among the cases was detected in relation to cumulative exposure to ra don.