External radiation exposure and mortality in a cohort of uranium processing workers.

In a study of 2,514 White male workers employed between 1942 and 1966 at a US uranium processing plant, mortality was compared with overall US mortality, and the relation between external ionizing radiation and cancer was evaluated. Through 1993, 1,013 deaths occurred. The mean cumulative dose was 47.8 mSv. The standardized mortality ratio (SMR) was 0.90 for all causes of death and 1.05 for all cancers. Many cancer sites had elevated SMRs. Among nonmalignant outcomes, the SMR for chronic nephritis was 1.88 (six deaths observed). An excess relative risk estimate of 10.5 per Sv (10 cases) was observed for kidney cancer; this may have resulted from chance, internal radiation, or chemical exposures not considered.