Objective The Paducah Gaseous Diffusion Plant (PGDP) became operational in 1952; it is located in the western part of Kentucky. We conducted a mortality study for adverse health effects that workers may have suffered while working at the plant, including exposures to chemicals. Materials and Methods We studied a cohort of 6820 workers at the PGDP for the period 1953 to 2003; there were a total of 1672 deaths to cohort members. Trichloroethylene (TCE) is a specific concern for this workforce; exposure to TCE occurred primarily in departments that clean the process equipment. The Life Table Analysis System (LTAS) program developed by NIOSH was used to calculate the standardized mortality ratios for the worker cohort and standardized rate ratio relative to exposure to TCE (the U.S. population is the referent for age-adjustment). LTAS calculated a significantly low overall SMR for these workers of 0.76 (95% CI: 0.72–0.79). A further review of three major cancers of interest to Kentucky produced significantly low SMR for trachea, bronchus, lung cancer (0.75, 95% CI: 0.72–0.79) and high SMR for Non-Hodgkin's lymphoma (NHL) (1.49, 95% CI: 1.02–2.10). Results No significant SMR was observed for leukemia and no significant SRRs were observed for any disease. Both the leukemia and lung cancer results were examined and determined to reflect regional mortality patterns. However, the Non-Hodgkin's Lymphoma finding suggests a curious amplification when living cases are included with the mortality experience. Conclusions Further examination is recommended of this recurrent finding from all three U.S. Gaseous Diffusion plants.

Background:We sub-divided a cohort of 6820 workers at the Paducah (KY) Gaseous Diffusion Plant (PGDP) which was traced from 1953 to 2003. The subdivisions were made to assess the mortality risks in a sub-group of workers employed solely during the plant's refit period, a time of suspected higher exposure to metal dusts (nickel, arsenic, chromium and ura nium) and trichloroethylene. Methods: This article describes a comparison of exposures and causes of death for 754 workers employed exclusively during the period of 1975-1979, with 1554 workers who worked in this period as well as other years. This interval was when the gaseous diffusion cascade facilities were refit. The workers employed 'only' during this period have a variety of deterministic factors (age-at-hire, duration of employment) that distinguish this sub-group of employees from the 'longterm' workforce. Results: The 'only 1975-1979' workers had a larger fraction of minorities and female workers. This 'only' subgroup was disproportionately employed in unskilled labor positions. The 'only' workers were younger than the referent group, and a 14-year earlier mean age at death. The all-cause mortality standardized rate ratio [SRR] was 1.58 [95% Cl: 0.97-2.42]. The 'only' group was significantly different from the 'ever' workers with respect to suicides, SRR = 3.74 [95% Cl: 1.86-6.69], and for homicides, . Conclusions: These elevated mortality risks do not seem to be due to PGDP employment exposures to metal dusts or trichloroethylene. Socio-economic factors may be a determinant for the patterns of suicides and murders described for this sub-group of employees. These findings provide guidance for communities with a dominant local employer. Persons who experience shortterm hiring may warrant public health services to mitigate their risk of tragic deaths. A case-control study of these deaths is recommended to clarify individual risk behaviors.