Cadmium in kidney

Impalas (Aepyceros melampus) found dead in Kruger National Park, South Africa, had elevated concentrations of copper in livers (maximum 444 mg/kg FW) and kidneys (maximum 141 mg/kg FW) authors assert that copper poisoning is the most likely cause of death (Gummow et al. 1991), but this needs verification. Copper concentrations in bones, kidneys, and livers of white-tailed deer (Odocoileus virginianus) near a copper smelter and from distant sites are about the same. However, deer near the smelter have significantly elevated concentrations of cadmium in kidneys and livers, lead in bone, and zinc in kidneys (Storm et al. 1994). 

In terrestrial mammals, cadmium tends to accumulate with increasing age in kidneys and livers of hares, moles and shrews, deer, caribou (Rangifer tarandus), and musk ox (Ovibos moschatus). Concentration of cadmium in kidney of deer increased from <0.002 mg/kg DW at age zero to 10.5 at age 7 years in males in females, these values were 6.5 mg/kg DW at age 3, 12.5 at age 7, and 20.0-... 

E ig. 4. Schematic representation of cadmium accumulation in renal cortex as a function of duration of exposure. Corresponding levels of cadmium in kidney cortex (CdKc), liver (CdL), and urine (CdU) and of the estimated cadmium body burden (Cd-body) are indicated. The CdU levels were obtained from (a) the relationship log CdU.CdKc or (b) the relationship log CdU.-Cd-body. These relationships between the various parameters apply only to Cd workers without renal dysfunction (from Roels et al. 1981a)... 

Cadmium is effectively accumulated in the kidneys. When the cadmium concentration exceeds 200 gg/g in the kidney cortex, tubular damage will occur in 10% of the population, and proteins begin to leak into urine (proteinuria). When the concentration of cadmium in the kidney cortex exceeds 300 pg/g, the effect is seen in 50% of the exposed population. Typically, excretion of low-molecular weight proteins, such as beta-microglobulin, is increased, due to dysfunction of proximal tubular cells of the kidney. The existence of albumin or other high-molecular weight proteins in the urine indicates that a glomerular injury has also taken place. The excretion of protein-bound cadmium will also be increased. 

The site of accumulation may define tlie point of toxic action. Inorganic mercury accumulation in the kidneys causes sever functional impairment Kidney damage has been shown to occur when the accumulated total of cadmium in the kidney cortex reaches 100-200 ppm... 

Barregard, L., Svalander, C., Schiitz, A., Westberg, G., Blohme, I., Molne, J., Attman, P.-O., and Haglind, P., Cadmium, mercury and lead in kidney cortex of the general Swedish population A study of biopsies from living kidney donors, Environment and Health Perspectives, 107, 867-871, 1999. 

There is a protein, metallothionine, which is found in kidney and which binds cadmium and zinc very effectively. This may well be related to the bacterial protein. We see that biological systems have developed highly selective ways of countering the influence of poisonous metals. The protection involves the interaction between a selected protein and a given metal. We can now return to platinum chemistry. 

Cadmium is nutritionally non-essential, toxic and a ubiquitous environmental pollutant. It is found in leafy vegetables, grains and cereals, and since it is present in substantial amounts in tobacco leaves, cigarette smokers on a packet a day can easily double their cadmium intake. It has a long biological half-life (17-30 years in man), accumulates in liver and kidneys and its toxicity involves principally kidney and bone (Goyer, 1997).While Cd interferes primarily with calcium, it also interacts with zinc and can induce the synthesis of metallothionein. Cadmium bound to metallothionein in liver or kidney is thought to be non-toxic, but cadmium in plasma... 

Recommendations for cadmium in air and human health protection under the worst scenario (Table 1.8) assume that total daily air intake is 27.14 m3 for an adult human who spends about 6.3 h in occupational exposure to air containing 100 pg Cd/m3 (USEPA 1980). Under these conditions, a 70-kg adult would retain about 361 pg Cd/day, based on an absorption factor of 0.5 (USEPA 1980), and most of this cadmium would probably be translocated to the kidney a critical threshold level of 200 mg Cd/kg in the kidney would be reached in about 1.52 years. It is not now known... 

In birds, copper concentrations in kidneys of the willow ptarmigan (Lagopus lagopus) are positively correlated with concentrations of cadmium (Wren et al. 1994). 

Females fed diets for 12 weeks containing 80 mg Pb/kg ration (as lead acetate) alone or in combination with 8 mg Hg/kg (as methylmercury chloride), or 80 mg Cd/kg ration (as cadmium chloride), ora mixture of Pb, Hg, and Cd Renal corpuscles of ducks fed Pb, Fig, or Cd alone or in two-way combinations had minor ultrastructural changes when compared to controls. The diet containing all three metals caused marked ultrastructural changes in kidney 40... 

Rao, P.V.V.P., S.A. Jordan, and M.K. Bhatnagar. 1989. Ultrastructure of kidney of ducks exposed to meth-ylmercury, lead and cadmium in combination. Jour. Environ. Pathol. Toxicol. Oncol. 9 19-44. 

Holterman, W.F.M.O., P. de Voogt, and J.H.J.C. Peereboom-Stegeman. 1984. Cadmium/zinc relationships in kidney cortex and metallothionein of horse and red deer histopathological observations on horse kidneys. Environ. Res. 35 466-481. 

Sato, M. and Y. Nagai. 1989. Effect of zinc deficiency on the accumulation of metallothionein and cadmium in the rat liver and kidney. Arch. Environ. Contam. Toxicol. 18 587-593. 

Several occupational studies reveal that cadmium can slowly accumulate in kidneys and impair kidney function. These studies involved exposure by... 

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