Urine chromium

There appears to be a chromium pool in individuals who are not chromium deficient (136). When there is an increase in level of cHculating insulin in response to a glucose load, an increase in circulating chromium occurs over a period of 0.5—2 h. This is foUowed by a decline and excretion of chromium in urine increases. Chromium deficiency is indicated when no increase or a small increase in blood chromium level or urine chromium occurs. 

Biological monitoring has been used to relate serum and urine chromium levels to occupational exposure levels. A statistically significant (r=0.95, p<0.001) relationship between total chromium exposure and urinary chromium concentrations at the end of the workday were observed in five welders exposed to chromium(VI) compounds. The urinary chromium concentrations of 40-50 pg/L immediately after work... 

Serum and urine concentrations of chromium were significantly elevated in a group of 73 tannery workers, compared to a group of 52 control subjects, at the end of the workweek on Friday and before exposure began on Monday. Serum and urine chromium levels did not correlate with length of... 

Ding WJ, Chai Z, Duan P, et al. 1998. Serum and urine chromium concentrations in elderly diabetics. Biol Trace Elem Res 63 231-237. 

Morris B, MacNeil S, Fraser R, et al. 1995b. Increased urine chromium excretion in normal pregnancy. Clin Chem 41(10) 1544-1545. 

Randall JA, Gibson RS. 1987. Serum and urine chromium as indices of chromium status in tannery workers. Proc Soc Exp Biol Med 185 16-23. 

Simpson JR and Gibson RS. 1992. Hair, serum, and urine chromium concentrations in former employees of the leather tanning industry. Biol Trace Elem Res 32 155-159. 

Sjogren B, Hedstrom L, Ulfvarson U. 1983. Urine chromium as an estimator of air exposure to stainless steel welding fumes. Int Arch Occup Environ Health 51 347-354. 

Intestinal absorption of is low, ranging from 0.4% to 2.5%, so fecal output is mainly unabsorbed dietary chromium. Absorption is increased marginally by ascorbic acid, amino adds, oxalate, and other dietary factors. After absorption, chromium binds to plasma transferrin with an affinity similar to that of iron. It then concentrates in human liver, spleen, other soft tissue, and bone. Urine chromium output is around 0.2 to 0.3 U,g/day, the amount excreted being to some extent dependent upon intake. Paradoxically, urine output appears to be relatively increased at low dietary levels. Thus 2% is lost in urine at an intake of lOpg/day, but only 0.5% at an intake of 40pg/day. Both running and resistive exercise increases urine chromium excretion. 

The detection of increased amounts of chromium in urine is a confirmation of recent occupational or environmental exposure to excess chromium. It also may be usefiil to monitor urine chromium in trials that use pharmacological dosages of chromium, both to confirm compliance and to detect potential toxicity. This is possible using available graphite furnace AAS instrumentation. ... 

Absorbed chromium is principally excreted in the urine with a small amount being eliminated in hair, sweat, and bile. Urine levels appear to be a useful indicator of chromium intake when dietary intake is >40 p.g/day however, excretion becomes constant when the intake is <40 jt,g/day. Urine chromium levels have been reported to be increased in diabetes, glucose loading, strenuous running, and physical trauma. Anderson has stated that urine chromium does not appear to be related to blood glucose, insulin, lipid, or any other studied clinical variables [11]. 

Urine chromium determined by ETAAS with Zeeman background correction and standard addition procedure outlined in this section has a reported detection limit of 0.1 p.g/liter. This is an outline of the method of Fleischer [46]. The reference provides detailed directions for this analysis. 

Total chromium in urine End of shift at end of workweek 30 pg/g creatinine B... 

Ross, R. T., Gonzalez, J. G., and Segar, D. A. "The Direct Determination of Chromium In Urine by Selective Volatilization with Atom Reservoir Atomic Absorption". Anal. Chlm. Acta (1973), 63, 205-209. 

There are a number of other elements appearing from time to time in the laboratory. From these, chromium and nickel are most common. Both appear in enhanced concentrations in workers exposed to welding fumes, in galvanization processes, and in processing of ores. Prolonged exposure to Cr and/or Ni causes cancer and affects the kidney. Preferred methods of determination of Ni and Cr in urine are GF-AAS. Because of the risk of contamination of the very low concentrations in urine, extreme precautions in sample handling and analysis must be carried out. 

S. Milardovic, Z. Grabaric, M. Tkalcec, and V. Rumenjak, Determination of oxalate in urine using an amperometric biosensor with oxalate oxidase immobilized on the surface of a chromium hexacyanoferrate-modified graphite electrode. J. AOAC Int. 83,1212—1217 (2000). 

Urine (anti- 12-hydroxy- endrin glucuronide) Addition of sodium metaperiodate to urine followed by heating to 70 °C for 45 minutes, addition of carbonate buffer, and extraction with hexane confirmation of analyte by conversion to 12-ketoendrine with chromium trioxide in ovridine GC/ECD No data 92 at 10.5 ppm Baldwin and Hutson 1980... 

An accurate determination of copper and zinc traces in human serum samples from the International Measurement Evaluation Programme-17 launched by IRMM (Geel) has been made by isotope dilution TIMS.38 An analytical method for the multi-element determination of metals (Ti, V, Cr, Co, Ni and Mo) potentially released from dental implants and prostheses into human body fluids (in blood and urine) by ICP-MS (double-focusing sector field instrument and quadrupole instrument with octopole collision cell) for medical studies was developed in Sanz-Medel s group.39 The Cr and Co concentrations found in blood samples of patients with chromium-cobalt based alloy varied in the sub-p,gl 1 range and were not significantly higher than the basal levels found by other authors.40... 

A gold(I)/tri(methoxyphenyl) phosphine complex incorporated into PVC membranes led to formulation of ISEs with fast (14 s) Nernstian response (10 2-10 6 M) to perchlorate, with excellent selectivity even over chlorate in both water and urine [28]. Chromium porphyrins in PVC gave ISEs with near-Nernstian response to salicylate (10 2-10 6 M) with UV spectra confirming binding of salicylate to the chromium atom [29]. 

An interesting finding regarding potentially toxic chromium (and cobalt) in the body is elevated blood and urine levels of these metals in patients who have undergone total hip replacement.5 The conclusion of the study was that devices such as prosthetic hips that involve metal-to-metal contact may result in potentially toxic levels of metals in biological fluids. 

Several biologically important metals can be determined directly in body fluids, especially urine, by atomic absorption. In the simplest cases, the urine is diluted with water or acid and a portion analyzed directly by graphite furnace atomic absorption, taking advantage of the very high sensitivity of that technique for some metals. Metals that can be determined directly in urine by this approach include chromium, copper, lead, lithium, and zinc. Very low levels of metals can be... 

Chromium can be measured in the hair, urine, serum, red blood cells, and whole blood. 

However, since chromium(III) is an essential nutrient, low levels of chromium are normally found in body tissues and urine. Tests for chromium exposure are most useful for people exposed to high levels. These tests cannot determine the exact levels of chromium you may have been exposed to or predict whether or not health effects will occur. High chromium levels in the urine and red blood cells indicate exposure to chromium(VT) or chromium(III) compounds. 

Since the body changes chromium(VI) to chromium(III), the form of chromium that you were exposed to cannot be determined from levels in the urine. Much more chromium(VI) can enter red blood cells than chromium(III), but chromium(VT) can be changed to chromium(III) within these cells. Therefore, chromium levels in the red blood cells indicate exposure to... 

Exposure of rats to sodium dichromate at 0.4 mg chromium(VI)/m3 for 90 days did not cause abnormalities, as indicated by histopathological examination of the kidneys. Serum levels of creatinine and urea and urine levels of protein were also normal (Glaser et al. 1985, 1990). Furthermore, no renal effects were observed in rats exposed to 0.1 mg chromium/m3 as sodium dichromate (chromium(VI)) or as a 3 2 mixture of chromium(VI) trioxide and chromium(III) oxide for 18 months, based on histological examination of the kidneys, urinalysis, and blood chemistry (Glaser et al. 1986, 1988). Rats exposed to 15.5 mg chromium(IV)/m3 as chromium dioxide for 2 years showed no histological evidence of kidney damage or impairment of kidney function, as measured by routine urinalysis. Serum levels of blood urea nitrogen, creatinine, and bilirubin were also normal (Lee et al. 1989). 

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