| This data file set consists of three analytic files for the cohort mortality study of white males employed at the Y-12 Facility in 1947 to 1974 by Harvey Checkoway, et al., published in the American Journal of Epidemiology in 1988. |
| This study examines the mortality of a cohort of 6,781 white males who worked at the Y-12 Facility for at least 30 days between May 4, 1947 and December 31, 1974. This cohort included workers who were known to have worked only at Y-12. Individuals who worked at Y-12 when TEC operated the facility (which was before May 4, 1947) or who worked at any other DOE-owned or operated facility were excluded. Workers in this cohort were exposed to low levels of alpha and gamma radiation while working with uranium compounds at an enriched nuclear materials fabrication plant. Relative to U.S. white males, the cohort experienced mortality deficits from all causes of death combined, from cardiovascular diseases, and from most site-specific cancers. When compared with national and state rates, excess mortality due to cancer of the lungs, brain, and central nervous system were seen. Dose-response trends, which diminished in magnitude when a 10-year latency assumption was applied, were detected for lung cancer mortality with respect to cumulative alpha and gamma radiation. The most pronounced trend associated with gamma doses was among workers who received doses equal to or greater than 5 rem of alpha radiation. There were 22 workers who received greater than or equal to 10 rem of external radiation, including 8 workers involved in a criticality accident at the facility in 1958. |
| There are three analytic files in this data file set. The first file, ORY12A01_d1 (LDBEST01), contains annual and cumulative lung doses for each person for the years 1947 through 1979. Estimates of doses delivered to the lungs were based on results of urinalysis measurements and in vivo counting of internally deposited uranium. The second file, ORY12A01_d2 (Y1ANGE14), contains demographic, work history, and vital status data for the cohort. The third file, ORY12A01_d3 (Y1ANFB03), contains annual and cumulative penetrating doses that were compiled from external personnel monitoring information. Periods in which a worker was not in the monitoring program were assigned doses of zero, under the assumption that only workers with a reasonable likelihood of exposure had been monitored. |
| Vital status was ascertained for 6,477 workers (95.5% of the cohort) through December 31, 1979, the study end date. There were 862 deaths identified (12.7%), and death certificates were obtained for 846 (98.1%) of these deaths. Eighty-five percent of the cohort was followed for at least 10 years. The median duration of follow-up was 20.6 years, and the cohort contributed 133,535 person-years of observation. |
| Workers at Y-12 were exposed to radiation resulting from external sources (primarily gamma radiation from the uranium decay series) and from internal deposition of uranium (primarily alpha particles). Personal monitoring for external exposure began in 1948 with the use of film dosimeters. They were used for personnel monitoring until the late 1970s, when they were replaced with TLDs. Monitoring for internal exposure to uranium began in 1950, but was not in full effect until 1953. By 1961, the internal monitoring program included in vivo measurements, such as lung counting. Metabolic models were used to convert urinalysis and in vivo measurements to lung doses for each worker. |
