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PubMed1984

Urinary excretion of chromium as an indicator of exposure to trivalent chromium sulphate in leather tanning.

Two workers exposed to trivalent chromium sulphate in a leather tannery had high concentrations of chromium in the urine. The concentration of chromium showed a workshift-related diurnal fluctuation, but it was remarkably high even after a vacation, indicating accumulation of chromium in the body. The concentrations of chromium in the workplace air, as collected on filters using standard techniques, were below 30 micrograms/m3. The chromium in the air was present in the form of large droplets not collected by the standard techniques. In the blood stream, chromium was transported exclusively in the plasma. No absorption of chromium through the skin could be detected. Absorption from the gastrointestinal tract was calculated to explain the findings.

Adult↗
PubMed1994

Nasal septum lesions caused by chromium exposure among chromium electroplating workers.

A chromium electroplating worker, suffering from epistaxis during work, was found to have nasal septum perforation. To determine the etiology and prevalence of nasal septum lesions, we conducted a survey of seven chromium electroplating factories and examined 79 workers. Forty workers from three aluminum electroplating factories were also enrolled as the reference group. Subjects were thoroughly examined by an otolaryngologist and each of them provided a blood and urine sample. A questionnaire interview regarding symptoms of the upper respiratory tract, past medical history, life style, and work history was also conducted. Air chromium concentrations were measured by taking area samples for 4-6 hours. Based on field observation and chromium measurements, we divided chromium electroplating into three different exposure zones: workers directly dealing with electroplating tanks (n = 31), other process workers (n = 29), and office workers and drivers (n = 19). Among the 79 chromium electroplating workers, there were 16 cases of nasal septum perforation, and 42 with either scar formation or ulceration; 10 chromium electroplating workers developed skin ulcers after performing chrome plating. No workers from aluminum electroplating factories had any nasal septum or skin abnormalities. There was a consistent trend between the degree of chromium exposure and the signs and symptoms related to the nose, throat, and skin. Immediate improvement of occupational hygiene is warranted.

Adult↗
PubMed2005

Capillary electrophoresis hyphenated to inductively coupled plasma-sector field-mass spectrometry for the detection of chromium species after incubation of chromium in simulated sweat.

The presence of chromium in chromium-tanned leather represents a considerable health problem since it can lead to chronic allergic contact dermatitis. Apart from trivalent chromium (Cr(III)), which is used for tanning, leather often contains hexavalent chromium (Cr(VI)), resulting from the oxidation of Cr(III) during the tanning process. This study deals with the chromium compounds in simulated sweat when brought into contact with Cr(III) or Cr(VI) and with chromium-tanned leathers. A capillary electrophoresis (CE) method was developed, with inductively coupled plasma-sector field-mass spectrometry (ICP-SF-MS) for element-specific detection. Two different electrophoretic runs, applying once the positive and once the negative polarity mode, were necessary for the detection of positively and negatively charged chromium species. Although sometimes described in the literature, a pre-run derivatization of the chromium-species was not performed here to prevent species transformation. 50 mmol.L(-1) sodium phosphate at a pH of 2.5 was used as CE separation buffer and as make-up liquid for the CE-ICP-SF-MS interface. When applied to simulated sweat samples incubated with Cr(VI), this method showed that methionine is responsible for the reduction of Cr(VI) into Cr(III), which, at its turn, forms a complex with lactic acid. In the case of sweat plus Cr(III), the latter step was also seen. Applied to simulated sweat in contact with leather samples, the method developed showed the presence of the former species among a much more complex pattern.

Chromium↗
PubMed1997

Efficacy of chromium picolinate and chromium chloride as potential carcass modifiers in swine.

We conducted two experiments to evaluate the effects of chromium picolinate and chromium chloride (CrCl3) on growth performance, carcass composition, percentages and accretion rates of carcass tissues and chemical components, and blood metabolites in pigs. In Exp. 1, 35 individually penned pigs were fed a fortified, corn-soybean meal basal diet (.95% lysine) supplemented with 0, 200, or 400 micrograms/kg of Cr from chromium picolinate or 5,000 or 25,000 micrograms/ kg of Cr from CrCl3. Each diet was fed to seven pigs for 35 d (19.6 to 43.2 kg BW). Addition of 200 micrograms/kg of Cr from chromium picolinate increased ADG (P < .07) and ADFI (P < .03) but did not affect feed:gain ratio. Backfat measurements and longissimus muscle area were not affected by either source of Cr. The percentages of muscle, fat, bone, and skin from the right ham and the percentages of water, protein, lipid, and ash from the left carcass were not significantly altered by Cr. The addition of 200 micrograms/kg Cr from chromium picolinate increased (P < .07) the accretion rate of lipid in the carcass. In Exp. 2, 42 individually penned pigs (three from each of 14 litters) were fed a fortified, corn-soybean meal basal diet (.95% lysine from 19 to 55 kg; .80% lysine from 55 to 109 kg) without or with 200 micrograms/kg of Cr from chromium picolinate or 5,000 micrograms/kg of Cr from CrCl3. Dietary Cr addition had no effect on the performance or backfat measurements of the pigs; however, both sources of Cr increased (P < .07) longissimus muscle area. The percentages and accretion rates of muscle tissue were increased (P < .001) and the percentages of fat tissue were decreased (P < .001) in pigs fed Cr, with chromium picolinate being more effective than CrCl3 (P < .05). The percentages (P < .01) and accretion rates (P < .07) of carcass protein were increased and the percentages and accretion rates of carcass lipid were decreased (P < .04) in pigs fed Cr. No changes in blood metabolites occurred as a result of supplemental Cr in either experiment. These results suggest that chromium picolinate is more effective than CrCl3 and that Cr must be supplemented throughout the growing-finishing period to improve the carcass composition.

Animals↗
PubMed1982

Dialysis treatment of acute chromium intoxication and comparative efficacy of peritoneal versus hemodialysis in chromium removal.

External burns with chromic acid have been fatal even in cases with corrosions covering less than 10% of the body surface area. We observed a 19-year-old man with third-degree burns and chromium intoxication following accidental contact of both legs with chromium acid solution. The initial course was characterized by serum chromium levels known to be usually lethal (220 micrograms/100 ml), complete anuria, hepatic damage and progressive anemia. Aggressive peritoneal dialysis with a total duration of 252 h between the 4th and 22nd day after exposure caused a progressive decrease in serum chromium levels and resulted in a complete recovery after 35 days. The comparative efficacy of peritoneal versus hemodialysis in chromium removal was evaluated in 5 patients with acute renal failure who were treated with peritoneal dialysis and in 6 patients with end-stage renal failure who underwent hemodialysis. Following intravenous injection of 500 muCi51CrCl3 chromium clearance averaged 0.8 +/- 0.3 ml/min and 2.5 +/- 0.8 ml/min during peritoneal dialysis (n = 50) or hemodialysis (n = 24), respectively. It is concluded that hemodialysis is about 3 times as effective as peritoneal dialysis in chromium removal per unit of time. However, the possibility of applying uninterrupted peritoneal dialysis during the first few days suggests that this method is at least equivalent to hemodialysis for treatment in the initial stage of chromium intoxication.

Acute Disease↗
PubMed1975

[Studies on the behavior of chromium in serum and urine in polytraumatized patients as well as on the chromium concentration of various infusion solutions].

Determinations of the oligoelement chromium were carried out by flameless atomic absorption spectroscopy in serum, whole blood, and urine of patients, undergoing intensive care, as well as in a great part of the solutions used for parenteral nutrition. With rising amino acid and protein content, respectively, the chromium content of the infusion solutions increased due to contamination. Pure nonglucose-carbohydrate-electrolyte solutions contained 16.5-49.0 mug chromium/litre, amino acid-carbohydrate solutions 36.5-105.0 mug chromium/litre and human albumin solutions, depending on concentration, 86.9-394.2 mug chromium/litre. The average chromium concentration in the patients' serum was 11.3 +/- 0.26 mug/litre, which is twenty times more than the normal values determined by this method, and increased from 8.3 to 16.4 mug/litre within the first seven days. The urinary chromium concentrations were 37.7 +/- 4.1 mug/litre, being three times higher than the average serum values, but remained constant from day to day. The approximate chromium administration by parenteral infusion therapy was 160-250 mug chromium/day, the urinary chromium excretion was 111 +/- 20.5 mug/day. Consequently, great amounts of parenterally supplied chromium seem to be stored in the patients' tissues. Effects and risks for the organism caused by these unphysiological chromium concentrations are discussed.

Accidents, Traffic↗
PubMed2005

Non-destructive rapid analysis discriminating between chromium(VI) and chromium(III) oxides in electrical and electronic equipment using Raman spectroscopy.

The European Union has banned chromium(VI) compounds in electrical and electronic equipment (EEE), such as chromate conversion coating films. Chromium(III) compounds are not banned. Using Raman spectroscopy without any preparation, we distinguished chromium(VI) oxide from chromium(III) oxide and chromium(III) hydroxide in chromate conversion coating films. Raman bands of chromium(VI) oxide were detected in films at around 1000 and 500 cm(-1), while chromium(III) compounds generated no bands in the region between 2000 and 200 cm(-1). The analysis took about 1 min, whereas the usual diphenylcarbazide-colorimetric method for analyzing chromium(VI) compounds takes about 10 h.

Journal Article↗
PubMed1997

The effects of particulate cobalt, chromium and cobalt-chromium alloy on human osteoblast-like cells in vitro.

Particulate wear debris can induce the release of bone-resorbing cytokines from cultured macrophages and fibroblasts in vitro, and these mediators are believed to be the cause of the periprosthetic bone resorption which leads to aseptic loosening in vivo. Much less is known about the effects of particulate debris on the growth and metabolism of osteoblastic cells. We exposed two human osteoblast-like cell lines (SaOS-2 and MG-63) to particulate cobalt, chromium and cobalt-chromium alloy at concentrations of 0, 0.01, 0.1 and 1.0 mg/ml. Cobalt was toxic to both cell lines and inhibited the production of type-I collagen, osteocalcin and alkaline phosphatase. Chromium and cobalt-chromium were well tolerated by both cell lines, producing no cytotoxicity and no inhibition of type-I collagen synthesis. At the highest concentration tested (1.0 mg/ml), however, chromium inhibited alkaline phosphatase activity, and both chromium and cobalt-chromium alloy inhibited osteocalcin expression. Our results clearly show that particulate metal debris can modulate the growth and metabolism of osteoblastic cells in vitro. Reduced osteoblastic activity at the bone-implant interface may be an important mechanism by which particulate wear debris influences the pathogenesis of aseptic loosening in vivo.

Alkaline Phosphatase↗
PubMed1997

Chromium as an industrial carcinogen: Part II. Chromium in human tissues.

A continuation of the findings in a study of workers hired in 1931-1937 in a chromate plant, directed at the evaluation of the carcinogenic risk of insoluble, soluble, and total chromium. Chemical analyses of tissues of autopsies, identified by age at hire, cumulative exposure to insoluble, soluble, and total chromium and interval since last exposure are cited for three lung cancer cases. Histological identification of insoluble chromium was demonstrated. Marked deposition and retention of concentrations of chromium was noted 18.0 years since last exposure. In one case with cumulative exposure to insoluble chromium of 10.74 mg versus 0.63 mg for soluble chromium and histological demonstration of insoluble chromium, chrysotile was also identified.

Autopsy↗
PubMed2002

On-line filtration system for determining total chromium and chromium in the soluble fraction of industrial effluents by flow injection flame atomic absorption spectrometry.

Two manifolds were assessed for the purpose of determining both the total chromium content and that present as a soluble form in industrial effluents by flow injection flame atomic absorption spectrometry (FI-FAAS). To determine the chromium content in the soluble fraction the samples were used without additional treatment, a 0.45 microm filter being included in the FI system. To determine the total chromium content, the samples were acidified with nitric acid 20% (v/v) and heated for 30 s in a microwave oven (temperatures of about 70 degrees C were reached). The problem posed by the very different concentration range in which total and soluble chromium are present was overcome by using programmed flow rate methodology and by only partially emptying the sample loop. A personal computer controlled both the rotation speed of a peristaltic pump and the volume of sample injected into the system, thus obtaining the dispersion degree required. Using the manifold proposed, the chromium content in the soluble fraction can be determined in the 0.5-20 microg mL(-1) range using a 10 microg mL(-1) single standard for calibration. To determine the total chromium content, a calibration line in the 20-200 microg mL(-1) range was obtained using a single 50 microg mL(-1) chromium standard solution. The reliability of the semi-automatic devices was verified by comparing the results obtained with those found by treating the samples and using both FAAS in a conventional way and a spectrophotometric method using diphenylcarbazide at the 95% confidence level (ANOVA test). The proposed procedures showed a RSD lower than +/-3%.

Chromium↗
PubMed2004

Microscopic analysis of the chromium content in the chromium-induced malignant and premalignant bronchial lesions of the rat.

OBJECTIVE: Our previous studies demonstrated that the frequency of gene instability in lung cancer of chromate workers was very high, but the frequencies of the p53 and ras gene mutations were low. To clarify the carcinogenesis of chromate in the lung, we established a chromate-induced cancer model in the rat proximal airway and examined the relationship between chromium accumulations and the chromium-induced cancer and premalignant bronchial lesions of the rat. METHODS: Fifteen male, bred, 12-week-old Jcl-Wister rats were used. A pellet of strontium chromate were inserted into the bronchus of the rats. The rats were sacrificed 9 months after the pellet was inserted. We pathologically examined the region of the bronchi to which the pellet was attached. We quantified the amount of chromium accumulation in the bronchial lesions using a microscopic X-ray fluorescence analyzer. RESULTS: Of the 15 rats, 1 rat had a lesion of squamous cell carcinoma (SCC), 7 rats had carcinoma in situ (CIS) or dysplasia, 8 rats had squamous metaplasia, and 5 rats had goblet cell hyperplasia. The amounts of chromium accumulation in normal epithelium (n=24), goblet cell hyperplasia (n=14), squamous metaplasia (n=8), and dysplasia plus CIS plus SCC (n=9) were 500+/-1354, 713+/-1062, 941+/-1328, and 3511+/-4473 (mean+/-SD) counts/s/mA, respectively. The amount of chromium accumulation was significantly increased according to the progression of malignant change of the bronchial epithelium (Spearman's correlation coefficient by ranks, rs=0.454, P<0.01). CONCLUSIONS: The amount of chromium accumulation was significantly increased according to the progression of malignant change of the bronchial epithelium. Examining the genetic alterations of histologic changes in this model was helpful in elucidating the process of carcinogenesis of chromium in the lung.

Animals↗
PubMed2005

Unusual reactivity in a commercial chromium supplement compared to baseline DNA cleavage with synthetic chromium complexes.

Commercially available chromium supplements were tested for their DNA cleavage ability compared with synthetic chromium(III) complexes, including chromium(III) tris-picolinate [Cr(pic)3], basic chromium acetate [Cr3O(OAc)6]+, model complexes, and recently patented Cr-complexes for use in supplements or therapy. Four different supplements (P1-P4) were tested for their DNA cleaving activity in the presence and the absence of H2O2, dithiothreitol (DTT) or ascorbate. One supplement, P1, showed nicking of DNA in the absence of oxidant or reductant at 120 microM metal concentration. Different lot numbers of P1 were also tested for DNA cleavage activity with similar results. Commercial supplements containing Cr(pic)3 nicked DNA at 120 microM metal concentrations in the presence of 5 mM ascorbate or with excess hydrogen peroxide, analogous to reactions with synthetic Cr(pic)3 reported elsewhere. Another chromium (non-Cr(pic)3) supplement, P2, behaves in a comparable manner to simple Cr(III) salts in the DNA nicking assay. Chromium(III) malonate [Cr(mal)2] and chromium(III) acetate [Cr(OAc)] can nick DNA in the presence of ascorbate or hydrogen peroxide, respectively, only at higher metal concentrations. The Cr(III) complexes of histidine, succinate or N-acetyl-L-glutamate do not nick DNA to a significant degree.

Acetates↗
PubMed1997

Subtoxic intracellular trivalent chromium is not mutagenic: implications for safety of chromium supplementation.

For reasons that are outlined, toxicologists have long suspected that intranuclear trivalent chromium mediates much if not all of the well-documented genotoxicity of hexavalent chromium. However, more recent evidence suggests that this genotoxicity is in fact attributable to free radical damage catalyzed by hexavalent chromium under reducing aerobic conditions. Subtoxic intranuclear concentrations of trivalent chromium, while they can be clastogenic in vitro, do not appear to induce point mutations and thus are unlikely to mediate the carcinogenicity of hexavalent compounds. Furthermore, there is considerable doubt that sublethal doses of trivalent chromium can produce tissue levels high enough to induce clastogenic damage in vivo. These considerations elucidate the virtual non-toxicity of orally-administered trivalent chromium in any dose, and strongly suggest that dietary supplementation with trivalent chromium in reasonable amounts is unlikely to carry any genotoxic risk. However, further animal studies are advisable to rule out the possibility of clastogenicity when grossly 'megadose' amounts are ingested.

Animals↗
PubMed1992

Simultaneous determination of chromium(III) and chromium(VI) in aqueous solutions by ion chromatography and chemiluminescence detection.

A method for the simultaneous determination of chromium(iii) and chromium(vi) in a flow system based on chemiluminescence was developed. A Dionex cation-exchange guard column was used to separate chromium(iii) from chromium(vi), and chromium(vi) was reduced by potassium sulfite, whereupon both species were detected by use of the luminol-hydrogen peroxide chemiluminescence system. Linear calibration for both species was established over the concentration range 1-1000 micrograms l-1. The precision at the 20 micrograms l-1 level was 3.5% for chromium(iii) and 3.3% for chromium(vi), respectively. The detection limit was 0.5 micrograms l-1 for both species. Data were in agreement with Zeeman-effect background corrected atomic absorption spectrometry measurements.

Chromatography, High Pressure Liquid↗
PubMed1997

[Effect of chromium yeast and chromium picolinate on body composition of obese, non-diabetic patients during and after a formula diet].

The objective of this study was to assess the effects of chromium yeast and chromium picolinate on lean body mass during and after weight reduction with a very-low-calorie diet. 36 obese (BMI 33.7 +/- 5.4 kg/m2), non-diabetic patients aged 45 +/- 6 years undergoing a 8-week very-low-calorie diet followed by a 18-week maintenance period. During the whole 26 week treatment period subjects received either placebo or chromium yeast (200 micrograms/d) or chromium-picolinate (200 micrograms/d) in a double-blind manner. Body weight was measured as BMI and body composition after calculation from skinfold thickness. As a result all three groups showed comparable weight loss after 8 and 26 weeks. Lean body mass was reduced in all groups after 8 weeks. However, after 26 weeks chromium picolinate supplemented subjects showed increased lean body mass (p < 0.029) whereas the other treatment groups still had reduced lean body mass. Chromium picolinate, but not chromium yeast, is able to increase lean body mass in obese patients in the maintenance period after a very-low-calorie diet without counteracting the weight loss achieved.

Adult↗
PubMed1996

Speciation studies by capillary electrophoresis- Simultaneous determination of chromium(III) and chromium(VI).

A method for the simultaneous determination of chromium(III) and chromium(VI) by capillary electrophoresis (CE) has been developed. The chromium(III) has been chelated with 1,2-cyclohexanediaminetetraacetic acid (CDTA) in order to impart a negative charge and similar mobility to both the chromium(III) and the chromium(VI) species. The effects of the amount of the reagent, pH and heating time required to complete the complexation have been studied. Factors affecting the CE behaviour such as the polarity of electrodes and the pH of electrophoretic buffer have been investigated. The separated species have been monitored by direct UV measurements at 214 nm. The detection limits achieved are 10 microg/l for Cr(VI) and 5 microg/l for Cr(III) and linear detector response is observed up to 100 mg/l. The procedure has been applied to the determination of both chromium species in industrial electroplating samples and its accuracy was checked by comparing the results (as total chromium) with those of atomic absorption spectrometry. No interference occurred from transition metal impurities under optimized separation conditions. The method is also shown to be feasible for determining Cr(III) as well as other metal ions capable to form complexes with CDTA (like iron(III), copper(II), zinc(II) and manganese(II)) in pharmaceutical preparations of essential trace elements.

Journal Article↗
PubMed2005

A newly synthetic chromium complex--chromium(phenylalanine)3 improves insulin responsiveness and reduces whole body glucose tolerance.

Low-molecular-weight organic chromium complexes such as chromium picolinate are often used as dietary supplements to improve insulin sensitivity and to correct dyslipidemia. However, toxicity associated with such chromium compounds has compromised their therapeutic value. The aim of this study was to evaluate the impact of a newly synthesized complex of chromium with phenylalanine, Cr(pa)3 on insulin-signaling and glucose tolerance. Cr(pa)3 was synthesized by chelating chromium(III) with D-phenylalanine ligand in aqueous solution. In mouse 3T3-adipocytes, Cr(pa)3 augmented insulin-stimulated glucose-uptake as assessed by a radioactive-glucose uptake assay. At the molecular level, Cr(pa)3 enhanced insulin-stimulated phosphorylation of Akt in a time- and concentration-dependent manner without altering the phosphorylation of insulin receptor. Oral treatment with Cr(pa)3 (150 microg/kg/d, for six weeks) in ob/ob+/+ obese mice significantly alleviated glucose tolerance compared with untreated obese mice. Unlike chromium picolinate, Cr(pa)3 does not cleave DNA under physiological reducing conditions. Collectively, these data suggest that Cr(pa)3 may represent a novel, less-toxic chromium supplement with potential therapeutic value to improve insulin sensitivity and glycemic control in type II diabetes.

Adipocytes↗
PubMed2003

Determination of chromium(III) and total chromium in water by derivative atomic absorption spectrometry using flow injection on-line preconcentration with a double microcolumn.

A rapid and sensitive method has been proposed for the sequential determination of chromium(III) and total chromium in water samples by flame atomic absorption spectrometry combined with a flow injection on-line preconcentration on a double-microcolumn. The chromium(III) and total chromium in samples were retained on a double-microcolumn with a cation exchange resin, respectively, and eluted directly into a nebulizer by 3 mol L(-1) HNO3. The characteristic concentration (gives a derivative absorbance of 0.0044) and the detection limit (3sigma) for chromium were 0.512 microg L(-1) and 0.647 microg L(-1) for a preconcentration time of 1 min, respectively. This is an improvement of 20 and 14-times than those of conventional FI-FAAS. The proposed method allows the determination of chromium in the range of 0-90 microg L(-1) with a relative standard deviation of 3.63% at the 10 microg L(-1) level. The method has been applied for the analysis of chromium in reference water of National Research Center for Certified Reference Materials (GBW08607) and other water samples with satisfactory results.

Journal Article↗