Effect of nickel(II) chloride on iron content in rat organs after oral administration

The effect of oral administration of nickel(II) chloride on iron content in serum and certain body organs of rats was investigated. The male adult rats were given 300 and 1200 ppm Ni in drinking water for 90 d. The iron content in serum, liver, kidney, lung, spleen, and brain was analyzed 30 and 90 d postexposure. The hemoglobin, hematocrit, and body and organ weights were also measured. Nickel given in drinking water led to a pronounced increase in iron content in serum and the liver, as compared to control rats. This effect was related to Ni concentration in the water. There was not great time-dependent difference in the iron content as a response to continuous nickel treatment, except the lung of 1200-ppm Ni-treated rats. In relation to hematological parameters, Ni supplementation did not affect any of them. Body weight significantly decreased, and lung weight was significantly increased in 1200-ppm Ni-treated rats. The results of this study indicate that nickel ingestion (300 and 1200 ppm in the drinking water) induces the iron uptake by serum and some organs of rats. The highest amount of iron was found in the liver of all exposed animals, and the time-dependent difference in iron content was observed in the lung of 1200-ppm Ni-treated rats.     

Iron,copper, and zinc status in rats fed supplemental nickel

Literature data concerning the effect of increasing dietary Ni concentrations on Fe, Cu, and Zn status in rats are sparse and, in part, controversial. Therefore, the effects of the addition of either 0, 3, 50, or 100 mg Ni/kg diet on Fe, Cu, and Zn status of rats were investigated in two separate experiments. Purified diets were used that were composed according to the established nutrient requirements of rats. Ni in kidney was increased with increasing Ni intakes. Dietary Ni did not significantly influence Fe concentrations in plasma, liver, kidney, femur, and spleen. Likewise, the addition of Ni to the diet did not alter Cu status. Zn concentrations in femur were significantly decreased after feeding the diets with 100 mg Ni/kg. However, Zn in plasma, liver, kidney, and spleen was not affected. It is concluded that variations in dietary Ni concentrations have no major impact on Fe, Cu, and Zn status in rats.     

Levels and distribution of zinc,copper, magnesium,and calcium in rats fed different levels of dietary zinc

Effects of altered dietary zinc on levels of zinc, copper, magnesium, and calcium in organ and peripheral tissues were studied. When rats fed a zinc-deficient diet (1.3 μg Zn/g) for 28 d were compared with rats fed a control diet (37.5 μg Zn/g), levels of zinc were slightly lower in plasma, hair, and skin and 50% lower in femur and pancreas, whereas the levels of copper were higher in all tissue except plasma. Magnesium levels were higher than controls in the heart and lower in the spleen, whereas the calcium levels were lower in plasma, lung, spleen, kidney, and skin and strikingly higher in brain, hair, and femur. When rats fed a zinc-supplemented diet (1.0 mg Zn/g) were compared to the same conrols, levels of zinc in these were higher in all organs and peripheral tissues studied, except heart, lung, and liver; copper levels were higher in liver, kidney, and spleen; magnesium levels were significantly higher in the spleen, but were little affected in other tissues, although calcium levels were higher in pancreas, spleen, kidney, and skin and lower in plasma and hair. These data indicate that overall copper organ and peripheral tissue levels are affected inversely, and zinc and calcium levels directly, by zinc nutriture.     

The effect of sodium selenite toxicity on tissue distribution of zinc,iron, and copper in rats

Male Sprague-Dawley rats were used to determine the effects of suptoxic and toxic concentrations of selenite in the drinking water on tissue distribution of zinc (Zn), iron (Fe), and copper (Cu). Se (as sodium selenite) was provided in drinking water at concentrations of 0, 2, 4, and 8 ppm. At 19 d, half of the rats in 4 and 8 ppm Sesupplemented groups were kept on drinking water alone for additional 13 d. All rats were sacrificed at the end of 32 d of experiment. Heart, liver, and kidney were analyzed for the concentrations of Fe, Zn, and Cu by atomic absorption spectrophotometry and of Se by a fluorometric method. Results indicated that rats receiving 4 and 8 ppm Se in drinking water showed a marked reduction in food intake and a reduced growth rate. These adverse effects were quickly reversed when high Se intake was discontinued. Se toxicity caused minimal change in zinc status, reduced tissue iron concentrations and caused a marked increase in copper contents in heart, liver, and kidney. The latter findings were only partly reversed after removal of Se in drinking water. The accumulation of Cu in the tissues of Se-toxic rats provides the evidence of some interaction between Se and Cu.     

Effect of zinc on biological half-lives of 65Zn in whole body and liver and on distribution of 65Zn in different organs of rats following nickel toxicity

This study was designed to determine the effect of zinc on the biological half-lives of ⁶⁵Zn in whole body and liver and on distribution of ⁶⁵Zn in different organs of rats following nickel toxicity. Sprague-Dawley (SD) rats received either nickel in the form NiSO₄·6H₂O at a dose of 800 mg/L in drinking water, zinc in the form of ZnSO₄·7H₂O at a dose of 227 mg/L in drinking water, and nickel plus zinc or drinking water alone for a total duration of 8 wk. All of the rats were injected with a tracer dose of 0.37 MBq ⁶⁵Zn at the end of the treatment period. The effects of different treatments were studied on biological half-lives of ⁶⁵Zn in whole body and liver and on the distribution of ⁶⁵Zn in different organs of rats. In the present study, we have noted that nickel treatment to normal rats caused a significant decrease in the slow component (Tb₂) in liver, which improved following zinc supplementation. Nickel administration to normal-diet-fed animals caused significant lowering in the percentage uptake of ⁶⁵Zn values in the brain, liver, and intestine. However, the administration of zinc to nickel-treated rats improved the status of ⁶⁵Zn in different organs. The Tb₂ in the liver and the percentage uptake of ⁶⁵Zn values elevated following zinc supplementation to nickel-treated rats.     

In situ distribution and speciation of toxic copper, nickel, and zinc in hydrated roots of cowpea

The phytotoxicity of trace metals is of global concern due to contamination of the landscape by human activities. Using synchrotron-based x-ray fluorescence microscopy and x-ray absorption spectroscopy, the distribution and speciation of copper (Cu), nickel (Ni), and zinc (Zn) was examined in situ using hydrated roots of cowpea (Vigna unguiculata) exposed to 1.5 μm Cu, 5 μm Ni, or 40 μm Zn for 1 to 24 h. After 24 h of exposure, most Cu was bound to polygalacturonic acid of the rhizodermis and outer cortex, suggesting that binding of Cu to walls of cells in the rhizodermis possibly contributes to the toxic effects of Cu. When exposed to Zn, cortical concentrations remained comparatively low with much of the Zn accumulating in the meristematic region and moving into the stele; approximately 60% to 85% of the total Zn stored as Zn phytate within 3 h of exposure. While Ni concentrations were high in both the cortex and meristem, concentrations in the stele were comparatively low. To our knowledge, this is the first report of the in situ distribution and speciation of Cu, Ni, and Zn in hydrated (and fresh) plant tissues, providing valuable information on the potential mechanisms by which they are toxic.     

The Effect of Electrolyte Type and Concentration on the Release of Cd,Cu, Ni,and Zn in Some Contaminated Calcareous Soils

This paper reports the results of desorption experiments of cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn) from some contaminated calcareous soils under four electrolyte types (CaCl₂, MgCl₂, NaCl and Na₂SO₄) with different electrolyte concentrations (0.5, 4 and 10 mM). Among electrolytes, CaCl₂ significantly released more metals from soils. There was a negative relationship between total Cu and Zn content and percentage of Cu and Zn released (average of electrolyte concentrations) using CaCl₂ solution, indicating a higher Cu and Zn released when their total content was low. Generally, Cd, Cu, and Zn speciation was affected by both type of electrolytes and their concentrations, whereas Ni speciation stayed mostly stable and was almost unaffected by applied solutions. It can be suggested that beside competition with cations, chloro-complexation is important parameter in Cd release, while CuOH⁺, and to some extent ZnOH⁺ are important species affecting release of Cu and Zn. The distribution coefficient (K_d) values for each metals greatly varied with the types of electrolytes and electrolyte concentration. On the basis of average percentage of metal released under different electrolytes and concentrations the following sequences was found: Cd > Cu > Ni > Zn. The results are important in understanding the mobility of metals under different solutions and indicating that, Cd and Zn soils may pose a higher and lower mobility and ecological risk in contaminated calcareous soils, respectively.     

Effects of interaction between65Zn,cadmium, and copper in rats

Distribution and retention of zinc in the presence of cadmium and copper was studied in rats exposed repeatedly to these metals. The experiment was performed on white rats of the Wistar strain. The animals were divided into four groups/five rats each: 1)⁶⁵ZnCl₂; 2)⁶⁵ZnCl₂+CdCl₂; 3)⁶⁵ZnCl₂+CuCl₂; and 4) control group. Rats were administered sc every other day for two weeks:⁶⁵ZnCl₂−5 mg Zn/kg; CdCl₂−0,3 Cd/kg; and CuCl₂−2 mg Cu/kg. The zinc content was measured in rat tissues by γ-counting. Effect of Cd and Cu on subcellular distribution of zinc in the kidney and liver and on the level of metallothionein were also examined. Whole body retention of zinc under the influence of cadmium was lower than that observed in animals treated with zinc alone. However, copper increased twofold the whole body retention of zinc. Cadmium elevated the accumulation of zinc only in the kidneys nuclear fraction and liver soluble fraction. In the kidneys and liver, copper elevated the accumulation of zinc, in the nuclear, mitochondrial, and soluble fractions. The level of metallothionein-like proteins (MT) in the kidneys after a combined supply of zinc and copper was significantly increased with respect to the group of animals treated with zinc alone. These results indicated complex interactions between cadmium, copper, and zinc that can affect the metabolism of each of the metals.     

Effect of acute administration of mercuric chloride on the disposition of copper, zinc, and iron in the rat

The present study was designed to investigate the effect of mercuric chloride administration on copper, zinc, and iron concentrations in the liver, kidney, lung, heart, spleen, and muscle of rats. The results showed that after dose and time exposure to mercuric chloride, the concentration of mercury in the six tissues was significantly elevated. Data showed that there were no interaction between mercury and tissue iron. There was a considerable elevation of the content of copper in the kidney and liver. The most significant changes in the copper concentration took place in the kidneys. About a twofold increase in the copper content of the kidney was noted after exposure to mercuric chloride (3 mg and 5 mg/kg). Only slight elevations in the copper content occurred in the liver, especially in high dose and longer exposure time. In the remaining organs, the copper content was not changed significantly (p>0.05). The most significant changes in the zinc concentration took place in liver, kidney, lung, and heart (5 mg/kg). Marked changes in kidney zinc concentrations were observed at any of the specified doses. Zinc concentrations were significantly increased in kidney of rats sacrificed 9–48 h after sc injection of HgCl₂ (5 mg/kg); in liver obtained from rats at 18, 24, or 48 h after injection; and in lung after 24 or 48 h of treatment. The heart and spleen zinc concentrations were elevated at 24 and 48 h after injection of HgCl₂ (5 mg/kg), respectively. The results of this study implicate that effects on copper and zinc concentrations of the target tissues of mercury may play an important role in the pathogenesis of acute mercuric chloride intoxication.     

Age related changes in weight and the concentrations of zinc and copper in the brain of the adult rat

Two groups of adult male rats aged 15 weeks and 49 weeks, 15 rats in each group, were analysed for the concentrations of the trace elements zinc (Zn) and copper (Cu) in serum, liver, kidney, and five parts of the brain (cortex, corpus striatum, hippocampus, midbrain + medulla, and cerebellum). All organs increased in weight from 15 weeks to 49 weeks. In all parts of the brain, except for corpus striatum, there was a significant increase of the weights. The dry weight (% of wet) increased in all parts of the brain. In serum, the Zn and Cu concentrations increased from 15 weeks to 49 weeks. In the liver, both concentrations decreased and in the kidney the concentrations increased with increasing age. The Zn concentrations increased in cortex and corpus striatum and decreased in cerebellum and hippocampus. The Cu levels increased in all parts of the brain with the largest changes in corpus striatum. For rats aged 49 weeks, a significant correlation was found between the Cu concentrations of corpus striatum or midbrain + medulla and the fluid consumption. The findings of the present study reveal a dynamic age-related pattern of changes in the concentrations of Zn and Cu in different organs of the adult rat. This stresses the need of age-matching as an important control in experiment studies.     

The effect of malathion,diazinon, and various concentrations of zinc,copper, nickel,lead, iron,and mercury on fish

Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls.     

The effect that nickel,copper, and zinc salts have on seed germination and initial ontogenesis of water parsnip (<Emphasis Type="Italic">Sium latifolium</Emphasis> L.) and wood club-rush (<Emphasis Type="Italic">Scirpus silvaticus</Emphasis> L.)

The effect that nickel, copper, and zinc sulfates have on seed germination and the initial stages of the ontogenesis of water parsnip and wood club-rush has been investigated. Nickel and copper in the concentration range of 250–500 mg/l and zinc at a concentration of 500 mg/l were the most toxic for water parsnip seeds, while, for the wood club-rush seeds, maximum toxicity was observed at Ni and Cu concentrations ranging from 50 to 500 mg/l and at Zn concentrations of 250–500 mg/l. The development of water parsnip seedlings was normal at Ni concentrations of 1–25 mg/l, Cu concentrations of 1–10 mg/l, and Zn concentrations up to 50 mg/l; the development of wood club-rush seedlings was normal at a Ni concentration of 1 mg/l, and Cu and Zn concentrations of 1–25 mg/l. A further increase in the concentration caused photosynthesis suppression, slower growth of the vegetation organs, and their subsequent necrosis. Water parsnip is more resistant to the toxicants.     

Metabolism of zinc and copper in the neonate: Zinc thionein in developing rat brain,heart, lung,spleen, and thymus

In a continuing study of the importance of metallothionein (MT) in the growth and development of neonates, zinc and copper metabolism in rat brain, heart, lung, spleen, and thymus has been analyzed in 5, 10, 15, 20 and 25 day old rats. Total, cytosol, and MT zinc and copper concentrations and organ contents were determined. Zinc, but very little, if any copper was associated with MT in these organs. Concentrations ranged from 0.03 to 3.3 μg Zn in MT/g; organ contents ranged from 0.003 to 2.2 μg Zn in MT/organ. Brain exhibited the highest concentrations and contents of zinc in MT, approaching the levels found in kidneys. Rank order of organ contents of zinc in MT was brain > lung > heart, spleen, thymus, during this neonatal growth period. When organ growth was rapid, a large percentage (20–95%) of the cytosolic zinc present in these organs was associated with MT, as has been previously observed with liver, kidneys, and testes. None of these organs undergoes the dramatic changes in zinc and copper metabolism previously observed in neonatal rat liver and gastrointestinal tract, and in maturing testes. They are more comparable to kidneys in their concentrations of zinc in MT. Like testes, little copper is found in these organs.     

Kidney and liver metallothioneins in rats after administration of an organic compound

Intubation of rats with alpha-mercapto-beta-(2-furyl)-acrylic acid (MFA) for 5 days at 50 mg/kg caused a 7-fold increase in kidney copper concentration, a 2-fold increase in kidney zinc concentration, and a 20% increase in liver zinc concentration. The proteins which bound the increased metals were purified and identified as metallothioneins by their amino acid compositions. Two isoforms were isolated from each organ. Renal thioneins appeared identical to counterpart hepatic apoproteins, but the former bound Cu and Zn in a 2:1 mole ratio and the latter bound only Zn. Kidney contained over 10 times more metallothionein per g of tissue than did liver. In rats previously administered MFA, injection of cadmium sulfate resulted in rapid displacement of liver metallothionein-bound Zn by Cd under conditions where minimal metallothionein was found in Cd-dosed animals not administered MFA. We conclude that MFA induces metallothionein biosynthesis in kidney and liver of normal rats; this is a novel effect for an organic compound.     

Effects of Formaldehyde Inhalation on Zinc,Copper and Iron Concentrations in Liver and Kidney of Male Rats

In the present study, adult Wistar albino male rats were exposed to formaldehyde at different periods (subacute and subchronic) and concentrations (5.0 and 10.0 ppm) in order to figure out the changes in the concentration of Zn, Cu and Fe. It was observed that the formaldehyde inhalation caused gradual decline of body weights in the experimental groups when compared with control groups. It was found that subacute (4-week) or subchronic (13-week) exposure to formaldehyde for rats may cause growth retardation. After inhalation procedure, concentration of copper, zinc and iron were determined in liver and kidney tissues of rats using atomic absorption spectrophotometer. In addition, concentrations of Cu, Zn and Fe changed by the effect of formaldehyde in subacute and subchronic groups.     

Properties of metallothionein induced by zinc, copper and cadmium in the frog, Xenopus laevis

1. Repeated injections of zinc (Zn) and copper (Cu) into the frog Xenopus laevis caused accumulations of the respective metals in the liver and kidney. 2. The accumulated metals in the liver supernatant fractions were present as Zn- and Cu-binding proteins of the same properties as that of metallothionein (MT) induced by cadmium (Cd) injections. 3. The affinity of Zn, Cu and Cd ions to the metal-binding protein was in the decreasing order of Cu, Cd and Zn. 4. The Xenopus MT induced by Cd was unstable and disrupted easily to give two peaks as if the MT consists of two isometallothioneins.     

Elemental alterations during the exposure of 1,2-dichloroethane (EDC), Disulfiram (DSF), and EDC-DSF to male Sprague-Dawley rats

Trace elements participate in the organ specific impact of 1,2-dichloroethane (EDC) and Disulfiram (tetraethylthiuram disulfide; Antabuse (DSF)) administered singly or together, on male Sprague-Dawley rats exposed by diet (AIN-76) to DSF (0 and 0.15% for 10 d before and during exposure to EDC) and by inhalation to EDC (0,153, 304, 455 ppm (v/v); 7 h/d for 5 d/wk for 30 exposure days). Kidney, liver, spleen, and testes at exposure d 30 as well as progressive urine samples were examined for elemental content by simultaneous inductively coupled plasma atomic emission spectroscopy. Each compound singly or together produced EDC dose related (r≥0.8) changes in metal content in organs relative to controls. There were increases induced by EDC alone for P and Sr in the liver and decreases for Fe, Mg, and P in the spleen. EDC in DSF-exposed animals caused increases in Ca, Cu, Fe, Mn, and S and a decrease in K in the liver; increases in Ca, Cu, Fe, Mn, Mo, P, and S and a decrease of Zn in the testes; an increase in Fe and a decrease in K in the spleen; and an increase of P in the kidney. DSF alone increased Cu in the liver but decreased it in the testes and kidney; Pb was increased in the liver and kidney and Zn in the liver, spleen, and kidney; Al and Si were increased also in the liver, S in the spleen, and K in the kidney; Mn and Na were decreased in the kidney. The organs showing histopathology (the liver and testes) both showed increases in Ca, Cu, Fe, Mn, and S. Metals in urine characterized a “shock” impact of the initial exposure by initial excretion of Na and retention of most other elements. After steady state (>12 d), EDC alone caused increases for Sr and Zn; for EDC-DSF, EDC also decreased Na in addition to the changes elicited by DSF alone (increases in S and Zn and a decrease for Cu). The results were interpreted from the perspective of the effects of metals on the glutathione detoxicative pathway, the concentration of free diethyldithiocarbamate in urine, and an interaction with bone. Mechanisms of action of EDC, DSF, and EDC-DSF must include consideration of trace elements in addition to organic intermediates, metabolites, and enzymes.     

Electrochemical synthesis and crystal structures of nickel(II), copper(II), zinc(II) and cadmium(II) complexes with N,N′-bis[(4-methylphenyl)sulfonyl]ethylenediamine

The electrochemical oxidation of anodic metal (nickel, copper, zinc and cadmium) in acetonitrile solutions containing N,N′-bis[(4-methylphenyl)sulfonyl]ethylenediamine H₂L and an additional nitrogen coligand, such as 1,10-phenanthroline, yielded mixed complexes of general formula [ML(phen)₂] (M=Ni, Cu, Zn and Cd). The compounds have been characterized by microanalysis, IR and UV-Vis (Ni, Cu complexes) spectroscopy, FAB mass spectrometry, ¹H NMR spectroscopic studies (Zn, Cd complexes) and EPR spectroscopy (Cu and Ni complexes). All compounds have also been characterized by single crystal X-ray diffraction. The molecular structures of these compounds consist of individual monomeric molecules in which the metal atom is in an [MN₆] distorted octahedral environment.     

Changes in the total content of iron,copper, and zinc in serum,heart, liver,spleen, and skeletal muscle tissues of rats infected withTrypanosoma cruzi

The effects of theTrypanosoma cruzi infection on the total content of the essential trace elements iron (Fe), copper (Cu), and zinc (Zn) in serum, heart, liver, spleen, and skeletal muscle were determined in “Wistar” rats inoculated with reticulotropic “Y” strain trypanosoms (Tryps) in their slender blood form. The 250 rats were divided in two groups of 80 rats (L-1 and L-2) and one of 90 (C) used as controls. L-1 and L-2 were inoculated with 2×10⁵ and 5×10² Tryps, respectively. Ten rats of the C group were killed the inoculation day (i), and ten rats of each group chosen at random were killed and blood parasitemia determined at 5, 10, 15, 20, 25, 30, 60, and 90 post-i days covering the infection acute-phase myocarditis. Previously cryohomogenized and lyophilized tissues were digested in an HNO₃ ⁻ H₂O₂ mixture with the aid of a microwave oven, and the elements Fe, Cu, and Zn were determined by Flame Atomic Absorption Spectrometry. Generally, more intense changes were observed in the L-1 group. Serum Fe and Zn levels are lower and Cu levels higher in groups L-1 and L-2 than in C. However, Fe is not significantly sequestered in the liver during the acute phase of the infection as expected, but of the tissues studied, the spleen was the main site of Fe binding. Zn tended to increase in all tissues, except in the spleen, where during the acute phase of the infection, the total content of Zn in groups L-1 and L-2 was lower than in group C. Cu increased mainly in the spleen and muscle. In general, each tissue presented its own pattern of redistribution related to its nature, functions, and number of parasites inoculated, and these patterns may have been altered by the tropism of the parasite.     

Effects of the Oral Administration of K<Subscript>2</Subscript>Cr<Subscript>2</Subscript>O<Subscript>7</Subscript> and Na<Subscript>2</Subscript>SeO<Subscript>3</Subscript> on Ca,Mg, Mn,Fe, Cu,and Zn Contents in the Heart,Liver, Spleen,and Kidney of Chickens

This study aimed to investigate the effects of selenium on the ion profiles in the heart, liver, spleen, and kidney through the oral administration of hexavalent chromium. Approximately 22.14 mg/kg b.w. K₂Cr₂O₇ was added to water to establish a chronic poisoning model. Different selenium levels (0.00, 0.31, 0.63, 1.25, 2.50, and 5.00 mg Na₂SeO₃/kg b.w.) around the safe dose were administered to the experimental group model. Ca, Mg, Mn, Fe, Cu, and Zn were detected in the organs through flame atomic absorption spectrometry after these organs were exposed to K₂Cr₂O₇ and Na₂SeO₃ for 14, 28, and 42 days. Results showed that these elements exhibited various changes. Ca contents declined in the heart, liver, and spleen. Ca contents also decreased on the 28th day and increased on the 42nd day in the kidney. Mn contents declined in the heart and spleen but increased in the kidney. Mn contents also decreased on the 28th day and increased on the 42nd day in the liver. Cu contents declined in the heart and spleen. Cu contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Zn contents declined in the heart and spleen. Zn contents increased on the 28th day and decreased on the 42nd day in the liver and kidney. Fe contents decreased in the heart and liver. Fe contents increased on the 28th day and decreased on the 42nd day in the spleen and kidney. Mg contents did not significantly change in these organs. Appropriate selenium contents enhanced Mn and Zn contents, which were declined by chromium. Conversely, appropriate selenium contents reduced Ca, Fe, and Cu contents, which were increased by chromium. In conclusion, the exposure of chickens to K₂Cr₂O₇ induced changes in different trace elements, and Na₂SeO₃ supplementation could alleviate this condition.