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PubMed2004

[Extraction catalytic spectrophotometric determination of trace chromium by synergetic catalytic effect].

In this paper, a new synergetic extraction catalytic spectrophotometric method for the determination of trace chromium was studied. The method is based on the iron(III) and chromium(VI) synergetic catalyzed oxidation of o-aminophenol by hydrogen peroxide in weak acidic medium at pH 5.5. The reaction time, concentration of o-aminophenol in aqueous phase, and degree of reaction were controlled by extraction equilibrium. The absorbance of organic phase was measured at 424 nm. The linear range of the method is 0.0010-0.90 mg x L(-1). The detection limit for chromium(VI) is 5.0 x 10(-6) g x L(-1). The relative standard deviation (n = 11) for 0.20 microg x mL(-1) level of Cr(VI) is 2.0%. The method has been applied to the determination of chromium in tap water and waste water with satisfactory results.

Aminophenols↗
PubMed2005

[Regulation of chromium on gene expression of skeletal muscles in diabetic rats].

OBJECTIVE: To study the regulation of chromium on gene expression related to metabolism of skeletal muscles in diabetic rats. METHODS: Male Wistar rats were assigned to three groups: normal control group (NC), alloxan-induced diabetic control group (DM), and DM with chromium supplementation group (DM + Cr). 200 microg Cr/kg bw perday was supplemented orally for 60 days. At the end of the treatment, the changes in gene expression among three groups were studied by mRNA differential display technique combined with cDNA fragments cloning, sequencing and BLASTn analysis. RESULTS: 11 cDNA fragments larger than 400bp expressed differences in skeletal muscles between DM + Cr group and DM group were isolated, 4 of them expressed higher in DM + Cr group, while the rest expressed higher in DM group. Cr-3 and GLUT4 are homologous with sequence identities of 98% and Cr-5 and IRS-1 are homologous with sequence identities of 100%. The expression level of GLUT4 mRNA in DM + Cr group are higher than those of DM group. CONCLUSION: Chromium supplementation could induce the expression of GLUT4 mRNA on skeletal muscles in diabetic rats. It may be one of the molecular mechanisms that chromium could improve the disorders of glucose and lipids metabolism in diabetic rats.

Animals↗
PubMed1992

Blood chromium and nickel in relation to respiratory symptoms among industrial workers.

Seventy-eight workers exposed to fumes and dust of nickel and chromium in their occupation in the glass industry were studied for respiratory symptoms in relation to nickel and chromium concentrations in their blood. A significant (p less than 0.01) association was observed between respiratory symptoms and elevated blood nickel and chromium. An interaction between nickel and chromium was found in relation to the prevalence of respiratory symptoms.

Adolescent↗
PubMed2006

[Effects of chromium and fish oil on the level of leptin and insulin in obese rats].

OBJECTIVE: In order to study the effects of chromium and fish oil on the level of leptin and insulin in obese rats, 32 obese model rats were divided randomly into four groups: fish oil group (5 ml/kg bw), chromium group (3 mg/kg bw), fish oil + chromium group and high fat diet group. METHODS: In the end of the experiment (6 weeks) fats around kidney and spermary were weighted and blood samples were collected to determine the level leptin and insulin. RESULTS: The results showed that the level of leptin and insulin in experimental groups were lower than those in high fat diet group. The ratios of fats around kidney and/or around spermary to body weight in experimental groups were lower than those in high fat diet group. CONCLUSION: Chromium and fish oil possible depress the high level of leptin and insulin in obese model rats.

Animals↗
PubMedDate not supplied

[Clinical and toxicologic problems related to acute poisoning with chromium].

Clinical course and toxicological findings in 18 patients intoxicated with ingested chromium salts are presented. Seventeen of these patients ingested potassium and sodium dichromate while the remaining patient--chromic acid. The first stage of 6-valent chromium is characterized by its irritating effect on the gastro-intestinal mucous membrane manifested by diarrhoea, vomiting often with blood, leading to severe water-electrolyte disorders, acidosis and shock. Lesions to kidneys, liver and myocardium may develop in the next stage. Probably endothelium is also in injured with resulting increase in its permeability. Acute renal failure is not seen even with high levels of chromium in the urine provided, that the recovery from the shock is prompt, and adequate diuresis induced with mannitol and/or furosemide is maintained. All patients with blood chromium concentration exceeding 1 mg/100 g died. This level is of prognostic and diagnostic value indicating an ingestion and absorption of the high doses of this metal.

Adult↗
PubMed1990

Quantitative chemical analysis of nickel-chromium dental casting alloys.

Twenty-nine brands of dental casting nickel-chromium alloys made in Japan for small castings were analyzed by electron probe X-ray microanalyzer. Nickel-chromium alloys for metal-ceramic application were composed primarily of nickel, chromium, and molybdenum with the exception of one brand. Of the nickel-chromium alloys for inlay, crown, and bridgework applications, 11 of the 22 alloys were up to the standard of the Ministry of Welfare specifications. And additive metal elements of these alloys were molybdenum, iron, copper, manganese, aluminum, silicon, tin, indium, silver, titanium, and gallium.

Chromium Alloys↗
PubMed1990

Cadmium, nickel, chromium and lead accumulate in human lymphocytes and interfere with PHA-induced proliferation.

The in vitro effect of five toxic metals (cadmium, lead, nickel, barium, chromium III and VI) on PHA-induced blastogenesis in human lymphocytes was investigated by [3H]-thymidine incorporation. With the exception of hexavalent chromium, the metals tested were in the chloride forms. The levels of metals associated with lymphocytes were measured under our experimental procedure. An inhibitory effect was found when cadmium was added at doses which closely approximate those of occupationally exposed subjects. Hexavalent chromium and nickel showed a biphasic pattern, with a stimulatory effect at the lowest concentrations tested (10(-8)-10(-6) mol/L) and an inhibitory effect on thymidine incorporation at concentrations higher than 10(-6) and 10(-4) mol/L, respectively. No effect was observed when lead, barium, and trivalent chromium were added to the culture medium. All metals showed the ability to enter the lymphocytes or to adhere to their surface, and the interaction appeared to be quite stable, with the exception of barium. The relationship between metal accumulation and [3H]-thymidine incorporation in the cells is discussed.

Adult↗
PubMedDate not supplied

[Effects of hexavalent chromium at non-lethal concentrations on the enzymology of the intestine of Salmo gairdneri and Dicentrarchus labrax (Pisces)].

Effects of non lethal concentrations of hexavalent chromium on intestinal enzymology of Salmo gairdneri and Dicentrarchus labrax (Pisces). The effects of an exposure to potassium dichromate on intestinal enzyme activities (Alkaline phosphatase, maltase, leucine amino peptidase and ATPases) have been studied on a fresh water fish (Salmo gairdneri) and a salt water fish (Dicentrarchus labrax). Fish were exposed at seasonal temperatures (13 or 21 degrees C) to toxic concentrations equal to 1/10 of the 24 h-LC 50 (i.e. 18 mg/l Cr for trout and 5 mg/l Cr for bass) during respectively 13 and 21 days. Intoxicated trout stopped feeding and showed a decrease in their intestinal weight at the end of the experiments. A decrease of brush border membrane activities (Alkaline phosphatase, maltase and leucine amino peptidase) were also observed. These alterations have been interpreted as the consequence of the chromium induces fasting. Intoxicated bass showed no alterations of their feeding habits. Two specific effects of chromium on enzyme activities have been found: a severe decrease of the alkaline phosphatase activity and an increase of the Na/K ATPase activity. These enzyme activities could be useful indicators of chromium intoxication in marine fish.

Adenosine Triphosphatases↗
PubMed1988

Concentration of nickel and chromium in serum: influence of blood sampling technique.

In the determination of nickel and chromium in serum, contamination is the most important source of error. In this study the influence of needle type and collection device was investigated. For each of 20 subjects the concentrations of nickel and chromium in serum obtained by the following techniques of blood collection were compared: closed collection system (acidwashed polyethylene syringes) + (A) steel needle (Terumo), (B) teflon i.v. cannula (Abbocath-T), and (C1) teflon i.v. cannula (Venflon); (C2) open collection system (acidwashed polyethylene tubes) + teflon i.v. cannula (Venflon). For each technique the first 5 ml of blood were discarded. No statistically significant differences were found between serum concentrations of nickel and chromium in specimens collected with the sampling techniques A, B, C1 and C2. This study has shown that identical results for concentrations of nickel and chromium in serum are obtained independent of whether a steel needle or a teflon i.v. cannula is used for blood sampling, provided the first 5 ml of blood are discarded. Likewise, identical results are obtained independent of whether specimens are collected in a closed or an open collection system, provided collection devices are acidwashed and sampling takes place under hospital conditions.

Adult↗
PubMed1988

[Preanalytical factors in chromium analysis of blood samples].

The problems connected with the collection of blood samples for chromium determination are shown with particular reference to the risk of chromium contamination which characterizes venous and capillary blood sampling. The use of various types of blood taking equipment (syringes with steel needles, platinum/ruthenium needles, intravenous catheters and lancets in steel of quarz) have been compared and analyzed (with references to the potential sources of chromium contamination during the collection and conservation of blood samples). By the use of the use of ETA-AAS "Zeema" procedure the references values of chromium in serum, read cells and whole blood in normal unexposed subjects living in a region of Northern Italy (Lombardy) have been determined.

Blood Specimen Collection↗
PubMed1988

Influence of chronic diabetes on tissue and blood cells status of zinc, copper, and chromium in the rat.

The influence of chronic diabetes on zinc, copper and chromium status in the urine, plasma, liver, kidney, bone, muscle, lymphocytes and erythrocytes was investigated in rats 180 days after streptozotocin injection, in comparison to age matched normal rats. The concentration and tissue content of zinc and copper were increased significantly in the liver, femur, erythrocyte and lymphocyte of the diabetic rats in addition to an increase in their urinary loss. In contrast, the concentration of zinc, copper and chromium in the kidney of the diabetic rats and the concentration of copper in the muscle and of chromium in the liver of the diabetic rats were similar to those of the normal rats. There was also a marked deficiency of zinc in the muscle and of chromium in the bone of the diabetic rats. The potential significance of altered trace metal metabolism during long term changes in endocrine status, and the possible explanation and significance of the variable concentrations of essential metals in different organs of streptozotocin induced chronic diabetic rats is discussed. The importance of erythrocyte and leukocyte zinc concentration as a mirror to their relative concentration in other tissue of animals and humans with type I diabetes is raised.

Animals↗
PubMed1986

Chromium metabolism and its role in disease processes in man.

Chromium is an essential element required for normal carbohydrate and lipid metabolism. Insufficient dietary Cr has been linked to maturity-onset diabetes and cardiovascular diseases. The dietary Cr intake of most individuals is considerably less than the suggested safe and adequate intake. Consumption of refined foods, including simple sugars, exacerbates the problem of insufficient dietary Cr since these foods are not only low in dietary Cr but also enhance additional Cr losses. Chromium losses are also increased due to pregnancy, strenuous exercise, infection, physical trauma and other forms of stress. Supplementation of Cr to normal free-living individuals often leads to significant improvements in glucose tolerance, serum lipids including high-density lipoprotein cholesterol, insulin and insulin binding. Chromium also tends to normalize blood sugar. Chromium supplementation of subjects with elevated blood sugar following a glucose load leads to a decrease in blood sugar while hypoglycemics respond to supplemental Cr by an increase in hypoglycemic glucose values, increased insulin binding and alleviation of hypoglycemic symptoms. In summary, dietary intake of Cr is suboptimal and this is exacerbated by increased Cr losses due to stress and certain refined foods including simple sugars that enhance Cr losses. Supplemental Cr is associated with improvements of risk factors associated with maturity-onset diabetes and cardiovascular diseases.

Adult↗
PubMed1986

[Behavior of the trace element chromium in coronary arteriosclerosis].

The present literature is submitted to a searching examination concerning the behaviour of the trace element chromium in coronary arteriosclerosis. Since 1978 chromium has been determined by three research groups in the plasma or serum of patients with ischaemic heart disease, in which cases their results are contradictory. The reason is evident: it is difficult to measure reliably the element chromium and the appearing problems are occasionally underestimated. Reliable and reproducible determinations of chromium demand especially equipped laboratories in order to avoid the contamination of tests, a sensitive and specific equipment and above all very experienced analyticians.

Chromium↗
PubMed1985

Chromium-induced cross-linking of nuclear proteins and DNA.

The in vivo cross-linking of proteins to DNA in intact Novikoff ascites hepatoma cells exposed to the chromium salt K2CrO4 was studied. DNA-protein complexes were assayed by high speed centrifugation of cells solubilized in buffered 4% sodium dodecyl sulfate and by electrophoretic identification of proteins associated with DNA-containing pellets. Further evidence of DNA-protein complexes, not dissociable in this buffer, was obtained by CsCl gradient centrifugation. Time dependence experiments showed that detectable cross-linking occurred after cells were exposed to chromium salt for at least 4 h, and the amount of DNA-protein complexes increased with longer incubation times. Complex formation occurred only with chromium salt concentrations of 200 microM or greater, and maximal cross-linking was effected at 5 mM. Immunotransfer methodology employing antibodies to nuclear matrix fraction and lamins was used to identify some of the polypeptides comprising the cross-linked complexes. These studies indicated specificity of chromium-induced complex formation within the nuclear protein fractions assayed. Our results document the ability of chromate to produce specific DNA-protein cross-links in living cells.

Animals↗
PubMed1985

Arsenic toxicosis and suspected chromium toxicosis in a herd of cattle.

Arsenic toxicosis and suspected chromium toxicosis were diagnosed in a herd of cattle that ingested ashes from lumber treated with copper, chromium, and arsenic. Findings included peracute death, depression, ataxia, weakness, recumbency, and watery diarrhea. Chemical analyses of liver, kidney, abomasal contents, rumen contents, and ashes revealed high concentrations of arsenic and chromium. Histologically, specimens of abomasum and duodenum had diffuse mucosal degeneration and engorged capillaries. Epithelial cells of the proximal convoluted tubules and distal collecting tubules of the kidney were swollen and had mild granular cytoplasmic degeneration. Burning lumber treated with copper, chromium, and arsenic does not remove the heavy metals from them, and ingestion of the ashes from the wood constitutes a hazard to livestock health.

Animals↗
PubMed1984

Kinetics of nickel and chromium in rats exposed to different stainless-steel welding fumes.

The kinetics of nickel and chromium from welding fumes were studied in the rat. To study the retention, the duration of exposure was one hour per working day for one, two, three, and four weeks. For the clearance study the follow-up period after four weeks' exposure was 106 days. Multi-element chemical analysis of the fumes and dried lungs was done using instrumental neutron activation analysis, and the concentrations in the body fluids were determined by atomic absorption spectroscopy. The maximum lung retention of metal inert-gas (MIG) welding fumes was somewhat higher than that of manual metal arc (MMA) welding fumes. The estimated maximum concentrations in the lungs were 9.5 micrograms/g and 150 micrograms/g for nickel after four weeks' exposure to MMA and MIG welding fumes. The corresponding concentrations of chromium were 78 micrograms/g and 310 micrograms/g. The measured concentrations were lower, however. The amounts of nickel cleared from the lungs during the MMA and MIG exposures were 0.9 microgram and 8 micrograms. The corresponding amounts of chromium were 9.6 micrograms and 2 micrograms. Practically all of the lost metals were found in the urine, in which the excretion rates were 0.07 microgram/d (MMA) and 0.39 microgram/d (MIG) for nickel and 0.23 microgram/d (MMA) and 0.11 microgram/d (MIG) for chromium.

Aerosols↗
PubMedDate not supplied

Chromium: an essential micronutrient.

A balanced, varied and "prudent" diet is likely to furnish the chromium requirement, whereas a high-fat, high-sugar, high-alcohol diet would not. A "prudent" diet will confer health benefits in addition to those derived form the adequacy of chromium intake, and it will obviate the need for supplementation with chromium compounds that are commercially available, but not scientifically proven to be effective. Chromium supplementation, other than by dietary means, should be used only when advised by and under the supervision of a physician.

Adult↗
PubMed1982

Lipid accumulation in chromium poisoned rats.

Interference of chromium with the hepato-renal lipids in rat (Rattus rattus albino) was investigated using histochemical and biochemical parameters. Present results show that chromium stimulates the accumulation of triglycerides and phospholipids in both liver and kidney. Biochemical data on total lipids show that chromium enhanced the rate of lipid accumulations. Since lipids accumulate if the factors necessary for their utilization are missing, it is concluded that chromium manipulates an increase in the input of free fatty acids (FFA) causing triglyceride formation and inhibits mitochondrial phosphorylation. Inhibition of esterases has also been proposed as the reason for increased phospholipid accumulation.

Animals↗