Mortality among male workers at a thorium-processing plant

摘要: The long-term health effects of exposure to thorium are interest because the possible increased use as an energy source in reactors using 232Th produce 233U. Mortality is described a cohort 3039 men who were employed between 1940 and 1973 at company involved production rare earth chemicals from monazite sand. Based on deaths ascertained by Social Security Administration mortality rates for U.S. white males, standardized ratio (SMR) all causes was 1.05 with 95% confidence limits (95% CL) 0.96 1.15. Much excess attributable non-occupational motor vehicle accidents (SMR = 1.64; CL 1.16 2.23), but SMRs also high lung cancer (1.44; 0.98 2.02), pancreatic (2.01; 0.92 3.82), diseases respiratory system (1.31; 1.83). In subgroup 592 worked least one year selected jobs (indicative highest thoron) that followed up more intensively, SMR significantly elevated (i.e. 4.13; 1.34 9.63). 1.68 0.81 3.09), while 1.20 0.52 2.37). Information smoking habits sample survivors suggested could have explained part system. Continued follow-up through morbidity studies needed evaluate further radioactivity extraction process.