Mortality study of Los Alamos workers with higher exposures to plutonium

A group of white male workers with the highest internal depositions of plutonium at the Los Alamos National Laboratory was selected in 1974 for a study of mortality. This group of 224 persons includes all those with an estimated deposition (in 1974) of 10 nanocuries or more of plutonium, principally /sup 239/Pu but also in some cases /sup 238/Pu. Follow-up of these workers is 100% complete through 1980. Smoking histories were obtained on all persons. Exposure histories for external radiation and plutonium were reviewed for each subject. Standardized mortality ratios (SMR) were calculated using rates for white males in the United States population, adjusted for age and year of death. SMRs are low for all causes of death (56; 95% CI 40, 75) or for all malignant neoplasms (54; 95% CI 23,106). Cancers of interest for plutonium exposures, including cancers of bone, lung, liver, and bone marrow/lymphatic systems, were infrequent or absent. The absence of a detectable excess of cancer deaths is consistent with the low calculated risk to these workers using current radiation risk coefficients. An alternate theory that suggests much higher risk of lung cancer due to synergistic effects of smoking and inhaled insoluble plutonium particles is notmore » supported by this study.« less