| This analytic data file set consists of one file generated for a retrospective cohort mortality study of all workers at the K-25 Facility in Oak Ridge, Tennessee, who were employed for at least 30 days and hired before January 1, 1985 by Donna Cragle. |
| Of the 35,712 workers in the study cohort 72.1% were white males, 3.4% were nonwhite males, 22.6% were white females, and 1.9% were nonwhite females. Full-scale operation at the facility began in January of 1945, and more than 57% of the members of study cohort were hired by the end of that year. Although the plant was in operation until 1985, less than 16% of the cohort was employed for 10 or more years, while 44% was employed for less than 1 year. Unlike most occupational cohorts, no healthy worker effect was seen for these workers. Further, there were statistically significantly elevated standardized mortality ratios for white males for all causes (1.03, 95% CI = 1.01- 1.05), along with malignant and non-malignant respiratory diseases and bone cancer. |
| The single analytic file, ORK25A02_d1 (ANALUPD1), contains a record, which includes vital status as of January 1, 1990, demographic, and work history data, for 40,785 employees of both genders and all races who were employed for at least 30 days and hired before January 1, 1985. Due to "critical errors" in their data, mainly missing race, gender, or paycode status, 5,073 of these individuals were eliminated from the study cohort. |
| The last SSA submission for this population provided "alive" status as of January 1, 1985. The "alive" category is no longer obtainable from SSA. However, NDI provides a record of all deaths occurring since January 1, 1979. If not identified as deceased by SSA or NDI, individuals last known to be alive before January 1, 1979 were considered lost to follow-up on the last date known alive while those known to be alive after January 1, 1979 were considered alive at the end of the study. There were 12,848 deaths from all causes with death certificates available for 97.8% of these individuals. The number of deaths by race/gender groups were 10,956 white males, 370 nonwhite males, 1,412 white females, and 110 nonwhite females. |
| K-25 produced enriched uranium through gaseous diffusion processes. There were numerous occupational exposures at the site with soluble uranium being a major contributor. Other potential hazards included some external radiation, insoluble uranium oxides, uranium hexafluoride, hydrofluoric acid, solvents, laboratory chemicals such as fluorocarbons, metallic nickel, and epoxy resins and hardeners. Mortality outcomes of special interest because of the particular occupational exposures present included cancers of the respiratory, lymphatic, and hematopoietic systems and non-malignant diseases of the kidney and respiratory system. |
