| This analytic data file set consists of three files constructed for a cohort mortality study of production workers at the Hanford Site in Richland, Washington for NIOSH by Steve Wing et al., University of North Carolina at Chapel Hill. |
| The Hanford Site was constructed along the Columbia River in South Central Washington State during World War II as a plutonium production factility. After the war, the Hanford Site continued to produce plutonium for the U.S. weapons arsenal and also conducted research and development in reactor design, fuel fabrication, chemical separations, and biological effects of plutonium. |
| The first file is a general analysis file HFWC94A1_d1 (hfan2g01). This file consists of a single record for each worker who met the criteria for inclusion in the study. It contains demographic, vital status, cause of death, and essential work history information. Records are identified by the research staff at the University of North Carolina at Chapel Hill (UNCID). |
| The second file contains annual external doses, HFWC94A1_d2 (hfan2a01). This single record file consists of a record for each worker in the study. Records are identified by UNCID. The file contains information on both recorded and estimated annual whole body doses for each year from 1944 to 1989. Annual whole body doses include cumulated gamma, x-ray, neutron, and tritium doses. Doses are recorded in mSv. |
| The third file contains plutonium exposure data, HFWC94A1_d3 (hfan2p01). This file consists of a single record for each worker in the study. Records are identified by UNCID. The file contains information on the number of days in each work year in routine plutonium exposed jobs, the number of days in each work year in non-routine plutonium exposed jobs, and information about workers with confirmed internal depositions of radioactive materials. |
| A study cohort of Hanford workers who were hired between 1944 and 1978 was defined. Workers had at least one annual external dosimetry record and had been employed at least 180 days by a prime contractor. Four workers were excluded due to involvement in radiation accidents and/or unusually high annual external radiation dose estimates (>250 mSv). In order to minimize problems of missing or incomplete radiation exposure information, workers known to have been employed at other Department of Energy sites and workers with dose records from nuclear sites, if doses were available only as cumulative doses, were excluded. In order to minimize potential bias due to long periods of worker selection prior to start of follow-up, workers who were first hired by construction contractors and those who were hired at Hanford 2 or more years prior to achieving eligibility for the study were excluded. |
| Follow-up of vital status was conducted through 1994 using information from Social Security Administration searches, records of the Health Care Financing Agency, the NDI, and the Washington State Department of Licensing (driver's license bureau). Workers who were confirmed alive as of January 1, 1979 were assumed to be alive December 31, 1994 if there was no indication of death through NDI or other sources. Workers who could not be identified as dead or alive at the end of 1994 were censored as of their date of last observation. Death certificates were obtained from state departments of vital statistics. Underlying and contributory causes of death were coded to the ninth revision of the International Classification of Diseases (ICD9). |
| A detailed work history file indicating dates of employment, as well as job titles and areas/departments, was constructed. External radiation dose was estimated via a nearby procedure for any year that a worker was employed at the Hanford site but an external radiation dose record was not available. In addition, the potential for plutonium exposure via a simple job exposure matrix was estimated. The matrix had three dimensions: job title, area/process (reactor, separations, research and development, other), and time period (1944 ro 1967 and 1968 to 1989). An industrial hygienist classified each cell in the table in the following categories: 0 = minimal potential for exposure to plutonium, 1 = non-routine or limited potential for exposure to plutonium, 2 = routine potential for exposure to plutonium. The number of days a worker spent in jobs with routine and non-routine potential for plutionium exposure was calculated. |
