SMRs were all below 100. All deaths from infective and parasitic diseases and diabetes were significantly lower in hourly but not salaried workers. Deaths from respiratory, gastrointestinal, circulatory, and genitourinary diseases were all significantly increased in both hourly and salaried workers, but SMRs were below 100. External causes of death were significant in salaried workers only, but again SMRs were below 100.
Mortality in 22,552 employees of the Atomic Weapons Establishment in the UK was studied by Beral et al. (1988). All employees who worked at the Aldermaston, Fort Halstead, Orfordness, Foulness, and Woolwich Common facilities at any time from January 1, 1951, to December 31, 1982, were included in the study. The average followup time was 18.6 years.
Exposure of 9,389 workers to uranium and other radiation sources was measured with dosimeters. The average cumulative whole-body exposure to external radiation was 7.8 mSv. Internal radiation dose was not estimated, because the dose probably would have varied from organ to organ and absorption and deposition of radionuclides are “often difficult to assess from external measurements.”
PYARs were calculated from the date of first hire or January 1, 1951, if the worker was recruited before then (records were incomplete before 1951). The data were stratified by age, sex, calendar period, and social class.
Overall mortality in the employees was lower than that in the general population. Mortality in the employees with radiation records was similar to that in other employees. However, after a 10-year lag, mortality from prostatic cancer (RR, 2.23; 95% CI, 1.13-4.56) and mortality from cancers of ill-defined and secondary sites (RR, 2.37; 95% CI, 1.23-4.56) were significantly increased. A significant dose-response trend was also noted for prostatic cancer when uranium exposure and cumulative whole-body exposure to external radiation were monitored.
The study used a relatively large cohort but was limited in that fewer than half the workers had individual monitored exposure and smoking information was lacking.
In this study of uranium workers in Egypt, Shawky and colleagues (2002) monitored external radiation exposure at two uranium-processing sites. The study population consisted of 86 processors at milling, monazite-production, and yellow-cake production locations who handled ores and materials that had high concentrations of naturally occurring radioactive materials. Work histories and descriptions were recorded. Dust monitoring and bioassays were conducted to determine radiation exposure of workers. Hematologic and renal-function measures were assessed in a clinical evaluation in which all study subjects