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PubMedDate not supplied

Blood distribution of nickel, cobalt, and chromium following intramuscular injection into hamsters.

In vivo experiments were undertaken to study the transport of metal ions away from the intramuscular (IM) injection site and to study the binding of the metals to blood cells. Hamsters were injected intramuscularly with metal salts or with corrosion products generated by fretting corrosion of 316 LVM stainless steel or MP-35N plates and screws. The animals were bled at 0 time, and 2, 4, 6, 24, 48, and 96 h after injection. The concentration of nickel, cobalt, and chromium in the serum, attached to red cells, and attached to white cells was determined. This study showed that metals are rapidly transported from the intramuscular site with high levels in the blood by 2 h. The level of metal in the blood varied considerably with nickel being transported in high concentration to the blood, chromium with a valence of 6+ being transported to the blood, and cobalt and chromium with a valence of 3+ being transported less to the blood. The highest amount of cell binding was observed with chromium 6+. Cobalt showed negligible binding to blood cells. When all the metal salts injected together were compared with the individual salts injected alone, there was no difference. This indicated that the each metal behaves independently of the presence of the others.

Animals↗
PubMed2003

Cytoprotective activity of Amla (Emblica officinalis) against chromium (VI) induced oxidative injury in murine macrophages.

The cytoprotective and immunomodulating properties of Emblica officinalis (Amla) against chromium (VI) induced oxidative damage are reported. Chromium (VI) at 1 micro g/mL concentration was highly cytotoxic. It enhanced free radical production and decreased reduced glutathione (GSH) levels and glutathione peroxidase (GPx) activity in macrophages. The presence of Amla resulted in an enhanced cell survival, decreased free radical production and higher antioxidant levels similar to that of control cells. Further, chromium (VI) treatment resulted in decreased phagocytosis and gamma-interferon (gamma-IFN) production while Amla inhibited chromium induced immunosuppression and restored both phagocytosis and gamma-IFN production by macrophages significantly.

Animals↗
PubMed2001

The effect of chromium on the hemoglobin concentration of Limnodrilus hoffmeisteri (Oligochaeta: Tubificidae).

The purpose of this study was to determine the toxic effects of polluted sediments, mainly chromium, the El Niagara reservoir (Aguascalientes, Mexico) on a benthic oligochaete species. Acute toxicity tests with hexavalent chromium in an artificial sediment-water system resulted in 24-, 48-, and 96-h LC50 values of 49.53, 22.81, and 5.11 mg available chromium/kg dry sediment, respectivley, in Limnodrilus hoffmeisteri. The uptake of chromium by tubificids from artificial and polluted reservoir sediments was found to increase with metal concentration in sediments and exposure time. The increase was higher in experiments with artificial sediment. Cr concentration in worms was related to hemoglobin content, which decreased significantly when Cr concentrations were above 1.0 microg/g dry weight. Bioavailable chromium in the El Niágara reservoir sediments may be an important factor limiting the benthic species in this ecosystem.

Animals↗
PubMed2002

Ecotoxicity of chromium (III) to Eisenia fetida, Enchytraeus albidus, and Folsomia candida.

Despite growing concerns about the potential adverse effects of elevated chromium concentrations in the environment, only a few terrestrial toxicity data are available. Therefore, chronic toxicity of chromium(III) was assessed for Eisenia fetida, Enchytraeus albidus, and Folsomia candida, the three invertebrates for which standard test protocols are available. The 21-day EC(50) for the cocoon production of E. fetida was 892 (679-1110) mg Cr/kg dry weight. Based on the reproduction, a 42-days EC(50) of 637 (355-791) mg Cr/kg dry weight was observed for E. albidus, while for F. candida a 28-day EC(50) of 604 (254-3380) mg Cr/kg dry weight was noted. Although the presented data can be considered a step forward in the assessment of the potential risks of chromium(III) in terrestrial environments, further research is needed to evaluate the influence of soil parameters on the toxicity of chromium and to quantify the effect of aging on bioavailability.

Animals↗
PubMed1993

Hygienic behaviour in chromium plating industries.

The impact of hygienic behaviour on the uptake of chromium has been studied in two small chromium plating factories. The correlation between the environmental monitoring measure (Cr-A) and the biological monitoring measure (Cr-U) varied between the two factories. In one factory (I) the correlation between Cr-U and Cr-A was 0.68 (P < 0.001), while in the other factory (II) it was negative (r = -0.64, P = 0.03). However, in both populations a significant impact of hygienic behaviour on the variance in Cr-U levels could be detected. In factory I, explained variance could be enhanced to R2 = 0.94 (P < 0.001) when considering expressions of hygienic behaviour. In factory II, a strong relation proved to exist between Cr-U and dermal uptake. For the various questions referring to skin problems and possible dermal uptake, the correlation with Cr-U is up to 0.70 (P = 0.03). When comparing the results for the two factories, it is shown that in addition to individual differences in hygienic behaviour, general hygienic conditions also have an impact on uptake of chromium. In factory II, where many efforts were made to prevent exposure to chromium, Cr-U was significantly lower than in factory I (P < 0.001).

Adult↗
PubMed1993

Danish external quality assessment scheme: an interlaboratory comparison study on lead, cadmium and chromium in lyophilized human blood concentrate.

A Danish External Quality Assessment Scheme (EQAS) was carried out by the Danish National Institute of Occupational Health during the period 1988-1992. The scheme was implemented for 29 international laboratories from 15 countries assaying lead, cadmium, and chromium in human blood to ascertain the systematic error and uncertainty of the analytical methods. In the survey the quality control material AMI B701-B705, based on lyophilized human whole-blood concentrate, were used. As an estimate of the true values the reference values used in this evaluation were (a) the computed values, i.e., sum of the basal and spiked trace element concentration, and (b) the consensus values normally used in the Danish EQAS. This international evaluation of lead, cadmium, and chromium in human blood demonstrated that the use of lyophilized human blood concentrate quality control materials combined with this scheme is valuable in estimating the systematic error and the uncertainty of the analytical methods. For evaluating analytical performance, the computed values were preferable to the consensus values for lead and cadmium in human blood. Due to analytical difficulties suitable reference values were not established for chromium in blood. The study revealed analytical difficulties for cadmium and chromium in human blood. The assessment of laboratories according to established performance indexes indicates that few laboratories can maintain these performance indexes.

Cadmium↗
PubMed1992

Modulation of chromium(VI) toxicity by organic and inorganic sulfur species in yeasts from industrial wastes.

Two chromium(VI) resistant yeast strains (Candida sp. and Rhodosporidium sp.) were isolated from industrial wastes. Four different yeasts, three from the Industrial Yeast Collection and one of pharmaceutical origin, were also studied in relation to chromate toxicity and its alleviation by sulfur species. The growth of yeasts from industrial wastes was inhibited by 50% by high concentrations of Cr(VI): Candida sp. by 4 mM Cr(VI) and Rhodosporidium sp. by 10 mM Cr(VI) in Sabouraud Broth medium. The other Cr(VI)-sensitive yeasts were inhibited by 0.1 mM Cr(VI). The general mechanism of chromium resistance in Candida sp. and Rhodosporidium sp. was due to reduced uptake of chromium, but not to biological reduction from Cr(VI) to Cr(III). In Cr(VI)-sensitive yeasts, chromium was accumulated as much as 10-fold, as in Saccharomyces cerevisiae. Cr(VI) toxicity in Candida sp. was modulated from Cr(VI)-resistance to Cr(VI)-hypersensitivity depending on the addition of methionine, cysteine, sulfate and djenkolic acid. If Candida sp. was grown in the presence of S-amino acids, especially methionine, it was more resistant than if the sulfur source was sulfate. When sulfate transport was enhanced by addition of djenkolic acid, Candida sp. became hypersensitive. Rhosporidium sp. was always resistant to Cr(VI) because sulfate transport was inefficient and it assimilated sulfur as S-amino acids. Cr(VI)-sensitive yeasts required larger amounts of S-amino acids, especially methionine, to tolerate Cr(VI) toxicity. Cysteine was toxic for C.famata 6016 above 50 microM.

Amino Acids, Sulfur↗
PubMed1989

Interaction between diazepam and oral antidiabetic agents on serum glucose, insulin and chromium levels in rats.

This study was undertaken to investigate the effect of diazepam in the presence and absence of glibenclamide, metformin or their combination on serum levels of glucose, insulin and chromium in rats. Results indicated that diazepam (10 mg/kg i.p.) induced marked hyperglycaemic effects in hyperglycaemic rats. This effect was associated with significant reductions in serum chromium levels and insignificant reduction in serum insulin levels. Diazepam-induced hyperglycaemia was counteracted by concurrent administration of glibenclamide (5 mg/kg orally), metformin (500 mg/kg orally) or their combination. The effect of diazepam on serum chromium level was counteracted partially by administration of glibenclamide and augmented in the presence of metformin or its combination with glibenclamide. It is concluded that the diazepam-induced hyperglycaemia, as well as the hypoglycaemic effect of glibenclamide, might be related to changes in serum chromium levels.

Animals↗
PubMed1995

[Chromium in Austrian foods].

The chromium content in foods is relatively low and the most foods have a content below 0.1 ppm. Only spices, cacao, cacao products, poppy and whole meal products contain higher contents. The often published high chromium content of corn germ oil could not be verified. We did not find any chromium enrichment in the entrails of a cow. In addition the chromium contents of each food are strong deviated. The analysed values were sometimes lower than in literature. We expect that the elder values are higher because of different contaminations in some cases.

Austria↗
PubMed1989

Copper, chromium, manganese, nickel and zinc in kidneys of cattle, pigs and sheep and in chicken livers in The Netherlands.

Kidneys of cattle, pigs and sheep and chicken livers have been analyzed for contents of copper, chromium, manganese, nickel and zinc. Mean levels found for copper, manganese and zinc correspond well with results of earlier studies as well as with literature data. Contents measured for chromium and nickel are very low: for nickel in porcine kidneys and sheep kidneys median values of 0.045 and 0.022 mg/kg were found. Average contents for nickel in the other tissues and for chromium in all tissues investigated are below 0.01 mg/kg fresh mass. These results for chromium and nickel correspond well with recent results from Sweden, but are lower than most published values.

Abattoirs↗
PubMed1976

The effect of in vivo chromium exposure on Na/K-and Mg-ATPase activity in several tissues of the rainbow trout (Salmo gairdneri).

The effect of in vivo chromium exposure on Na/K-and Mg-ATPase activity was studied in several tissues of the rainbow trout, Salmo gairdneri. Those tissues studied were: intestine, gill, liver, and kidney. Tissue chromium levels were determined for control rainbow trout and trout exposed to 2.5 mg Cr/1 (as chromate) for 48 hours. After exposure to chromium, inhibition of Na/K-ATPase activity, but not Mg ATPase activity, was observed. These results may partially explain the detrimental effects of hexavalent chromium on fish.

Adenosine Triphosphatases↗
PubMed1994

Death by tanning--a case of fatal basic chromium sulphate poisoning.

A woman ingested 400 ml of leather tanning solution containing 48 g of basic chromium sulphate (CrOHSO4). This substance forms hydrogen ions and trivalent chromium when it reacts with tissue proteins. The patient died of cardiogenic shock, complicated by pancreatitis and gut mucosal necrosis and haemorrhage. There are no reported cases of toxicity due to oral ingestion of trivalent chromium. Toxicity of hexavalent and trivalent chromium is discussed and suggestions made for management of future cases.

Adult↗
PubMed1992

Cytotoxic effects of hexavalent chromium in cultured murine macrophages.

The in vitro effect of hexavalent chromium (CrVI) on mouse peritoneal macrophages was investigated. Our results demonstrate the existence of a threshold concentration of 2.5 microM of CrVI above which chromium affects the viability of macrophages in a concentration dependent manner. Morphological changes were seen with increasing concentrations of chromium. Evidence is presented that protein production (virus-induced interferon) in murine peritoneal macrophages was impaired by hexavalent chromium at low concentrations, while random migration and phagocytic activity were only affected at high concentrations of CrVI.

Animals↗
PubMedDate not supplied

Chromium, glucose tolerance, and diabetes.

Chromium functions in maintaining normal glucose tolerance primarily by regulating insulin action. In the presence of optimal amounts of biologically active chromium, much lower amounts of insulin are required. Glucose intolerance, related to insufficient dietary chromium, appears to be widespread. Improved chromium nutrition leads to improved sugar metabolism in hypoglycemics, hyperglycemics, and diabetics.

Adolescent↗
PubMedDate not supplied

The isolation of glucose tolerance factors from brewer's yeast and their relation to chromium.

A new dietary factor, the glucose tolerance factor (GTF), was reported in 1957 that improved impaired glucose tolerance in rats. Most studies on GTF have used brewer's yeast as the starting material, and it has been postulated that the active material is a low-mol wt organic complex containing Cr3+. It seemed thus important to isolate an active GTF from chromium-rich yeast (228 ppm Cr) obtained by incubation with chromium and to compare each fraction with corresponding ones from untreated yeast (0.48 ppm Cr). We developed an isolation and purification procedure by fractionation of yeast extract on an anion and cation exchange resin, and tested the GTF activity (glucose oxidation) on rat adipocytes. PIXE (proton-induced X-ray emission) was used to measure the chromium content of the individual fraction. Individual fractions with GTF activity did not differ between Cr-rich and Cr-deficient yeast, and there was no relationship between Cr content and GTF activity. This does not support the hypothesis that chromium is an obligatory constituent of the GTF, assuming that GTF is a unique substance.

Adipose Tissue↗
PubMedDate not supplied

Chromium induced clinical improvement in symptomatic hypoglycemia.

The present study included 20 patients indicating clinical symptoms of hypoglycemia, of which 19 showed a minimal glucose level in the tolerance curve above 2.2 mmol/L (limit for glucose induced hypoglycemia). This clinical state is defined here as "symptomatic hypoglycemia." All individuals were studied for effects of a daily intake for three mo of a yeast chromium supplement (125 micrograms Cr/d). The patients were followed by means of their oral glucose tolerance curve (1 g glucose/kg body wt) and by an interrogation scheme prior to during and after chromium supplementation. During three mo of chromium supplementation, a decrease was found in the negative part of the glucose tolerance curve, i.e., the part of the curve being below the fasting level in eight patients (40%). However, one mo after treatment, 10 patients out of 13 (77%) showed decreased areas of the negative part of the glucose tolerance curve compared to the values during treatment, and 11 out of 15 (73%) showed decreases in the negative part of the curve when post-treatment data were compared to ante-treatment data. The subjective clinical effects were followed by means of a questionnaire. Subjectively, the effects of organo-chromium were especially pronounced on chilliness. Thus seven (47%) indicated improvement and two (15%) indicated that the chilliness disappeared. However, trembling, emotional instability, and disorientation symptoms improved as well.

Adult↗
PubMed2005

In vitro permeation of chromium species through porcine and human skin as determined by capillary electrophoresis-inductively coupled plasma-sector field mass spectrometry.

Since the species that trigger chromium allergy are not yet known, it is important to gain more of an insight into the mechanism of chromium transport through the skin and into the relationship between chromium allergy and chromium species. In vitro permeation studies with porcine and human skin were performed using a Franz static diffusion cell. Investigations attempted to elucidate (i) which Cr compounds are able to permeate through skin, (ii) the influence the Cr concentration in the donor solution has on the Cr permeation, and (iii) the effect that the time of exposure to the donor solution has on Cr permeation. Capillary electrophoresis hyphenated to inductively coupled plasma-sector field mass spectrometry (CE-ICP-SFMS) was used to separate and quantify the Cr species in the receptor fluid. 50 mmol L(-1) phosphate buffer (pH 2.5) was used for CE separation, and two different electrophoretic runs were carried out (in the positive and negative modes). Pneumatic nebulization (PN)-ICP-SFMS was used in order to quantify the total amount of Cr absorbed by the skin after microwave-assisted acid digestion of the tissue. Cr(VI) was found to pass most easily through the skin. Nevertheless, Cr(VI) was also shown to be absorbed more efficiently by the skin than Cr(III), an observation attributed to a more pronounced rejection of the positively charged Cr(III) ions by the skin barrier. These results were in good agreement with in vitro permeation studies previously reported in the literature in which other analytical techniques were used. Differences observed in the permeation of Cr following the application of aqueous Cr donor solutions and Cr-containing simulated sweat donor solutions are also described.

Acids↗
PubMed2000

Flame atomic absorption spectrometric determination of trace chromium in various standard samples after preconcentration with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol.

Chromium can be quantitatively retained as 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-tetra-phenylborate(TPB) complex onto microcrystalline naphthalene in the pH range 4.8-5.9 from a large volume of aqueous solutions of various standard samples. After filtration, the solid mass consisting of the chromium complex and naphthalene was dissolved with 5 mL of dimethylformamide and the metal was determined by air-acetylene FAAS. A detection limit of 4 ng/mL for chromium was established. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the trace determination of chromium in various standard alloys and biological samples.

Anions↗