| This analytic data file set consists of four files generated for the cohort mortality study of white males employed at ORNL by Harvey Checkoway, et al., published in the British Journal of Industrial Medicine in 1985. |
| The publication focuses on 8,375 white males employed at ORNL for at least 1 month (30 days) between 1943 and 1972. The study presents internal comparisons of mortality (standardized rate ratios) between subgroups of the cohort according to radiation dose level and duration of employment in various job categories. No consistent gradients of cause-specific mortality were assessed with respect to radiation exposure. Among monitored workers, deficits in mortality due to arteriosclerotic heart disease and all cancers were found. However, elevated (but not statistically significant) SMRs were seen for all leukemia, cancer of the prostate, and Hodgkin's disease. |
| There are four analytic files in the ORX10A01 data file set. The first file, ORX10A01_d1 (X1CH0210), provides information for 12 employment groupings, which were based on an examination of each individual's work history and on the calculation of a 10-year latency period for each person. The second file, ORX10A01_d2 (X1CH0810), contains external radiation doses as assessed from external monitoring data. The third file, ORX10A01_d3 (X1CH1201), contains all demographic data and summary exposure data pertaining to the cohort. This file contains one record per individual in the cohort, whereas the other files may contain several or no records per individual, depending on the availability of monitoring data for those individuals. The fourth file, ORX10A01_d4 (CUMEXP), contains all internal monitoring data pertinent to the cohort. |
| Vital status was ascertained for 92.2% of the cohort of 8,375 white males through December 31, 1977, the study end date. There were 966 deaths identified, and death certificates were obtained for 939 (97.2%) of these deaths. External and internal exposures to radiation were examined. |
| ORNL began monitoring personnel for exposure to penetrating external radiation, primarily gamma rays, in 1943. Pocket chambers were used until June 1944, when film dosimeters (film badges) became the primary dosimeters. Film dosimeters were used for personnel monitoring until 1975, when they were replaced with thermoluminescent dosimeters. From 1943 until the early 1950s, the usual practice was to provide personal dosimeters to only those workers entering designated areas where the potential for exposure was presumed to exist. Subsequently, all workers at ORNL were monitored for exposure to radiation. In 1951, based primarily on the potential for contamination from their work area, some workers began to be monitored by urine bioassays for internal exposure to radionuclides. Additional workers were monitored to evaluate exposures incurred during incidents. Internal exposures were determined by results of urine and fecal bioassays and whole- body counting. For purposes of the study, internal monitoring results were used to place the worker into one of three exposure categories each year. Quantitative dose estimates due to internally deposited radionuclides were not available because they usually were not required to be calculated in the past, and all of the basic data needed to compute doses for the many radionuclides used at ORNL were not computerized. However, knowledgeable plant health physicists and dosimetrists state that the majority of internal monitoring results for this cohort suggest small internal doses, especially when compared to external doses. |
