Natural radiation dose to Gammarus from Hudson River

The purpose of this investigation is to evaluate the natural radiation dose rate to whole body and components of the Gammarus species, a zooplankton which occurs in the Hudson River among other places, and to compare the results with the upper limits of dose rates from man-made sources. The alpha dose rates to the exoskeleton and soft tissues are about 10 times the average alpha dose rate to the whole body, assuming uniform distribution of 226Ra. The natural alpha radiation dose rate to Gammarus represents only about 5 p. cent of the total natural dose to the organism, i. e., 492 mrad/yr. The external dose rate due to 40K, 238U plus daughters and 232Th plus daughters accumulated in the sediments comprise 91 p. cent of that total natural dose rate, the remaining percentage being due to natural internal beta emitters and cosmic radiation. Man-made sources can cause an external dose rate up to 224 mrad/yr, which comprises roughly 1/3 of the total dose rate (up to 716 mrad/yr; natural plus man-made) to the Gammarus of Hudson River in front of Indian Point Nuclear Power Station. However, in terms of dose- equivalent the natural sources of radiation would contribute more than 75 p. cent of the total dose to Gammarus

Elemental concentrations in bones from an ancient Egyptian mummy and from a recent man

Differences in elemental concentrations in bones taken from an ancient Egyptian mummy and a contemporary man were investigated by using proton induced x-ray emission (PIXE) in combination with Rutherford backscattering (RBS). Remarkable differences were noticed in the Fe/Ca and Pb/Ca relative concentrations, which were consistently higher in the contemporary man. 5 refs., 2 figs., 2 tabs

Lung cancer in uranium miners and the implications of the U/V ratio in uranium-bearing particles

Several geological formations mined for uranium ore during and after the second World War had been mined earlier for vanadium. Most miners and millers from the Utah-Colorado mining region worked with this ore or its tailings at one time or another. Preliminary investigation to determine the size and location of uranium-bearing particles retained in the lungs of a former uranium miner and miller from this region, who died of lung cancer (mesothelioma), showed a high nonuniform distribution of vanadium. This observation leads to the hypothesis that the vanadium content in that lung could be associated with inhaled particles. Further examination of spectra of characteristic x-rays obtained by scanning microPIXE (particle induced x-ray emission) of an autopsy sample of this lung indicated that vanadium was indeed present in localized sites within the 20 ..mu..m spatial resolution of the proton beam. This work points out that the vanadium found in the lungs of this former miner and miller is nonuniformly distributed, and can be used for site localization and size determination of inhaled particles retained in the lungs. The meaning of U/V ratios in dust particles and in lungs is discussed. Further studies are in progress to: (1) locate uranium-bearing particles in lung tissues of former uranium miners and millers; and (2) evaluate the local alpha doses received from these particles. 11 refs., 3 figs., 1 tab