The second point makes the matrix matching of standards to samples for direct analysis impossible and, in order to normalize all samples to a similar matrix, the analysis of a diluted (or digested) solution is preferable. High instrumental sensitivity is then required to reliably measure the resulting single digit pg g-1 uranium concentrations. While the quantification of uranium is therefore d...

Uranium is an alpha-emitting, radioactive, heavy metal that occurs naturally in nearly all rocks and soils. Twenty-two isotopic forms of uranium have been identified, mainly associated with nuclear reactor operations or high-energy physics experiments; the most prevalent isotopes found in the environment are the three naturally-occurring isotopes: U, U, and U. Most uranium isotopes undergo deca...

Following exposure to aerosols of depleted uranium (DU), biological samples show the presence of a synthetic mixture of natural uranium and DU. By partitioning the uranium in the 24-h urine sample along the isotopic fractions of natural uranium and DU, one can study the kinetics of these subpopulations independently. A linear model is developed to estimate the lung burden of DU from measurement...

Slabs of natural and depleted uranium are used routinely to calibrate personal dosimeters and radiation survey instruments for beta radiation. However, little information is available on the absorbed dose rate produced by a uranium slab as a function of depth in matter. In this study, an extrapolation chamber was used to measure the dose rate produced by natural uranium at a variety of depths i...

Discharge from former uranium mining and milling areas is world wide a source of elevated uranium contents in wetlands. The efficiency of organic rich wetland environments for entrapment and accumulation of uranium was assessed in this work using hydrogeochemical field studies of natural small-sized wetlands in Thuringia and Saxony, Eastern Germany. The objective was to estimate, if artificial ...

Depleted uranium (DU) is a by-product from the chemical enrichment of naturally occurring uranium. Natural uranium is comprised of three radioactive isotopes: (238)U, (235)U, and (234)U. This enrichment process reduces the radioactivity of DU to roughly 30% of that of natural uranium. Nonmilitary uses of DU include counterweights in airplanes, shields against radiation in medical radiotherapy u...

A study of future energy requirements and of the potential of various energy sources (coal, oil, gas, nuclear power, hydropower and solar energy) indicates that the contribution to be made by nuclear fission, now competitive with conventional energy sources, will grow steadily over the next few decades. Whereas the amount of fuel which has to be fabricated each year for the operation of a nucle...

Uranium oxide particles were dispersed into the environment from a factory in Colonie (NY, USA) by prevailing winds during the 1960s and '70s. Uranium concentrations and isotope ratios from bulk soil samples have been accurately measured using inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) without the need for analyte separation chemistry. The natural range of uranium concent...

OBJECTIVES To assess the distribution and risk factors of depleted uranium uptake in military personnel who had taken part in the invasion of Iraq in 2003. METHODS Sector field inductively coupled plasma-mass spectrometry (SF-ICP-MS) was used to determine the uranium concentration and (238)U/(235)U isotopic ratio in spot urine samples. The authors collected urine samples from four groups iden...

Uranium accumulates in bone, affects bone metabolism in laboratory animals, and when ingested in drinking water increases urinary excretion of calcium and phosphate, important components in the bone structure. However, little is known about bone effects of ingested natural uranium in humans. We studied 146 men and 142 women 26-83 years of age who for an average of 13 years had used drinking wat...