Lung cancer mortality among nonsmoking uranium miners exposed to radon daughters.
Roscoe-RJ; Steenland-K; Halperin-WE; Beaumont-JJ; Waxweiler-RJ
JAMA J Am Med Assoc 1989 Aug; 262(5):629-633
A cohort mortality study of 516 white, male, nonsmoking uranium miners was performed to identify risk factors associated with lung cancer in this occupational group. Only men who had never smoked were selected from a larger cohort which had been followed for 35 years. Radon daughter exposure was expressed in terms of working months (WLM). Vital status was determined for each cohort participant from linkage with various federal records. Data were analyzed by a life table system developed for NIOSH. Person year calculations were made for strata defined by age, WLM, calendar periods, and periods after first uranium mining. Expected number of deaths was estimated, and standardized mortality ratios (SMR) were calculated. Comparisons were made with nonsmoking veteran's mortality rates, and with the general United States nonsmoking population. Mean age for living participants at the end of study was 56 years. Mean time in underground uranium mining was 52 months. Median radon daughter exposure was 296 WLM. Mean time from first mining employment to death or end of study was 28 years. A total of 14 lung cancer deaths were found. The SMR based on the veterans' comparison was 12.7. The Axelson rate comparison included 77 additional participants who were cigar and pipe smokers; 19 lung cancer deaths were found in this augmented cohort, resulting in an SMR of 9.3. The SMR calculated for nonmalignant respiratory disease mortality was 11.7. The authors conclude that exposure to radon daughters in nonsmoking underground uranium miners increases the risk of lung cancer death 12 fold.
NIOSH-Author; Lung-cancer; Epidemiology; Exposure-levels; Mortality-rates; Occupational-exposure; Radiation-exposure; Radiation-hazards; Radon-daughters; Underground-miners; Uranium-miners
Journal of the American Medical Association