Kidney uranium

Studies show that the main sites of uranium deposition ate the renal cortex and the Hvet (8). Uranium is also stored in bones deposition in soft tissues is almost negligible. Utanium(VI) is deposited mostly in the kidneys and eliminated with the urine whereas, tetravalent uranium is preferentially deposited in the Hvet and eliminated in the feces. The elimination of uranium absorbed into the blood occurs via the kidneys in urine, and most, - 84%, of it is cleared within 4 to 24 hours (8). 

Uranium as of 12/08/03 zero as of 12/08/03 30ug/L Increased risk of cancer, kidney toxicity Erosion of natural deposits... 

Animal studies indicate that the primary toxic effect of uranium exposure is on the kidney, with particular damage to the proximal tubules. Functionally, this may result in increased excretion of glucose and amino acids. Structurally the necrosis of tubular epithelium leads to formation of cellular casts in the urine. If exposure is insufficient to cause death from renal failure, the mbular lesion is reversible with epithelial regeneration. Although bone is the other major site of deposition, there is no evidence of toxic or radiocarcinogenic effects to bone or bone marrow from experimental studies. ... 

Nephrotoxins Hie tenn refers to a specific target organ characterization of effect. Nephrotoxins are chemicals which produce kidney damage. Signs and symptoms are edema and proteinuria. Examples are halogenated hydrocarbons and uranium. 

Once uranium is in the systemic circulation, it is transported as various complexes in the blood. The predominant form of uranium is as a bicarbonate complex, the stability of which is highly dependent on the pH of the solution (ATSDR, 1999 Chevari and Likhner, 1968). In the kidneys, the bicarbonate complex is filtered at the renal glomerulus and excreted in the urine (Adams and Spoor, 1974 ATSDR, 1999 Blantz, 1975 Bowman and Foulkes, 1970 Brady... 

Studies in humans have shown that approximately 66% of an intravenous injection of uranium is eliminated from the plasma within 6 min, while 99% of the uranium is eliminated from the plasma 20 hours after injection (ATSDR, 1999 Harley et al, 1999 Luessenhop et al, 1958). Another study has shown that the kidneys excrete over 90% of intravenously injected soluble hexavalent uranium salt, with less than 1% excreted in the feces approximately 70% of the dose is excreted within the first 24 h (Bassett et al, 1948). 

Adams, N., Spoor, N.L. (1974). Kidney and bone retention functions in the human metabolism of uranium. Phys. Med. Biol 19 460-71. 

Carriere, M., Avoscan, L., Collins, R., Carrot, F., Khodja, H., Ansoborlo, E., Gouget, B. (2004). Influence of uranium speciation on normal rat kidney (NRK-52E) proximal cell c 4otoxicity. Chem. Res. Toxicol. 17 446-52. 

When you eat foods and drink liquids containing uranium, most of it leaves within a few days in your feces and never enters your blood. A small portion will get into your blood and will leave your body through your urine within a few days. The rest can stay in your bones, kidneys, or other soft tissues. A small amount goes to your bones and may stay there for years. Most people have a very small amounts of uranium, about l/5,000th of the weight of an aspirin tablet, in their bodies, mainly in their bones. 

Like adults, children are exposed to small amounts of uranium in air, food, and drinking water. However, no cases have been reported where exposure to uranium is known to have caused health effects in children. It is possible that if children were exposed to very high amounts of uranium they might have damage to their kidneys like that seen in adults. We do not know whether children differ from adults in their susceptibility to health effects from uranium exposure. 

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