Levels of some trace elements in selected autopsy organs,and in hair and blood samples from adult subjects of the Italian population

This study, which is part of a research program for the determination of trace element reference levels in various human tissues for the Italian population, presents the concentrations of Se, Hg, Cr, Cs, Sc, Rb, Zn, Fe, Co, and Sb in lung, liver, spleen, and kidney autopsy samples taken from 14 adult subjects of the Italian population who died from accidental causes. Concentrations of the same trace elements are given also for blood and hair samples taken from subjects of the general Italian population and of a population group living in a small coastal town that has an average annual fish consumption well above the national average. The analytical method used was Instrumental Neutron Activation Analysis. The levels and distribution of the trace elements in the various human organs examined are analyzed and discussed.     

Correlations between trace element levels in head hair and blood components of Nigerian subjects

Elemental concentrations in head hair and blood (whole-blood, erythrocytes and plasma) of 28 Nigerian subjects were determined using instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE) techniques. Correlations found between different elements in hair and blood are reported. Hair levels of both zinc and chlorine were found to be significantly correlated with their levels in erythrocytes.     

Plasma trace elements concentrations in trained subjects after exposure to hypokinesia and daily hyperhydration

The objective of this investigation was to evaluate the effect of a daily intake of fluid and salt supplementation (FSS) on blood plasma trace elements concentrations in physically healthy volunteers after exposure to 364 d of hypokinesia (decreased number of steps per day). The studies were performed after exposure to 364 d of Hypokinesia (HK) on 30 long-distance runners of volunteers who had a VO₂ max 67 mL/kg/min and were ranging in the age of 19–24 yrs. Prior to their exposure to HK all volunteers were on an average of 10,000 steps/d. For the simulation of the hypokinetic effect the volunteers were kept under an average of 3000 steps/d. All volunteers were divided into three equal groups. The first group of volunteers subjected to HK and received daily FSS (water 26 mL/kg body wt and sodium chloride 0.16 g/kg body wt.), the second groups of volunteers submitted only to HK, and the third group of volunteers underwent a normal ambulatory life and served as control. The content of manganese, calcium, magnesium, iron, lead, copper, tin, nickel, zinc and cobalamine were determined in blood plasma of volunteers. By the end of the hypokinetic period the blood plasma concentration of microelements increased significantly in the hypokinetic subjects (second group), whereas in the hyperhydrated subjects (first group) decreased. It was concluded that prolonged restriction of motor activity induced significant increases in blood trace elements concentrations whereas daily hyperhydration had a normalizing effect on their concentration in blood plasma. This indicates that daily hyperhydration may be used to normalize blood plasma concentrations of microelements in physically healthy volunteers subjected to prolonged restriction of motor activity.     

Identifying sources of groundwater pollution using trace element signatures

A simple receptor modeling approach has been applied to groundwater pollution studies and has shown that maker trace elements can be used effectively in source identification and apportionment. Groundwater and source materials from one coal-fired and five oil-fired power plants, and one coal-tar deposit site have been analyzed by instrumental neutron activation analysis for more than 20 minor and trace elements. In one of the oil-fired power plants, trace element patterns indicated a leak from the hazardous waste surface impoundments owing to the failure of a hypolon liner. Also, the extent and spatial distribution of groundwater contamination have been determined in a coal-tar deposit site.     

Measurement of exchange of trace metals between the body and its surroundings with the use of trace methodology

Application of general tracer theory to the problem of estimating fluxes of tracee between the gastrointestinal tract and the body proper, from observations of the movement of tracer, shows that a number of assumptions must be fulfilled. Two specific sets of assumptions are discussed and, in both cases, measurement of tracer fluxes yields information on the integrated absorption of the tracee.     

Study of trace elements in blood of cancer patients by proton-induced X-ray emission (PIXE) analysis

Proton-induced X-ray emission (PIXE) analysis was employed to determine the concentrations of six elements in the plasma and erythrocytes of 18 cancer subjects (15 males and 3 females) with neoplastic disorders and in 70 controls (35 males and 35 females). It was found that the concentrations of Br, K, and Zn were significantly elevated in the erythrocytes of the cancer subjects compared to the controls, whereas the concentration of Fe was significantly depressed, but with no difference observed in the concentration of Ca. In the plasma, the concentrations of Br, Cu, Ca, and K were significantly elevated, whereas the concentrations of Fe and Zn were found to be significantly depressed compared to the controls.     

Magnesium loading effect on magnesium deficiency in endurance-trained subjects during prolonged restriction of muscular activity

The aim of this study was to evaluate the effect of magnesium (Mg) loading (10.0 mg Mg/kg body wt) and daily Mg supplements (5.0 mg Mg/kg body wt) on Mg deficiency shown by increased and not by decreased serum Mg concentration during hypokinesia (decreased km number/d). The studies were done during 30 d of prehypokinesia and 364 d of hypokinesia (HK) periods. Forty endurance-trained volunteers aged 22–26 yr with a peak VO2 max of 66.3 mL·kg⁻¹ min⁻¹ and with an average 15.0 km/d running distance were chose as subjects. They were equally divided into four groups:

Concentrations of essential elements after repeated administrations of tin and selenium

To study effects of simultaneous administration of tin (Sn) and selenium (Se) on concentrations of several essential elements, mice were injected with either SnCl2 (ip) or Na2SeO3 (sc), alone or both compounds at a daily dose of 5 mumol/kg each for 12 consecutive days. Mice were sacrificed at 20 h after the last injection and concentrations of Sn, Se, Na, Ca, Zn, P, Fe, K, and Mg in the liver, kidney, spleen, pancreas, testis, seminal vesicle, lung, femoral muscle, and femoral bone were determined. In the control mice, Sn and Se concentrations were the highest in bone (0.69 micrograms Sn and 6.93 micrograms Se/g dry wt). Administered Sn was found to accumulate in all organs except the testis. Among the essential elements determined, Na was the most affected in terms of concentration in the organs and Mg was the least affected element in these organs. Among the organs tested, each elemental concentration in the pancreas was most affected. Simultaneous injections of Sn and Se appeared to keep the correlation coefficients between elements similar to those found in the control mice.     

A survey of trace elements in fresh-water fish and rice along the Han River by neutron activation analysis

For a case study of environmental pollution, radiochemical neutron activation analysis (RNAA) was applied to the crucian and rice collected along the Han River. The crucian was analyzed for three times in 1973, 1987, and 1990. Sixteen trace elements (Hg, Cd, As, Br, Cu, Na, K, Se, Cr, Hf, Rb, Fe, Zn, Co, La, and Cs) were determined by RNAA using distillation and diethyldithiocarbamate extraction methods. Contents of Na, K, Se, Hf, Fe, Zn, and Co were almost constant regardless of the sampling place and year. The contents of the other elements showed increasing trends down river, especially in the first investigation. At the lower part of the river, the contents showed decreasing trends with the time of sampling, especially during the first two investigations. These trends were typical for Hg and Cd. Rice was analyzed by the same method for 12 elements, and the results showed no regional trends, but have decreased after 1973.     

Dietary calcium and blood lead levels in women

Nutritional factors are known to influence metabolism and toxicity of several metals in animal experiments, but relevant human data are scarce and inconclusive. In this work, we tested the hypothesis that dietary calcium influences lead metabolism in humans. Blood lead concentrations were used as indicators of lead exposure and metabolism. Two groups of peasant women living in similar conditions in two different regions in Yugoslavia (100 in each) were chosen as subjects for this purpose. In region A, the dietary calcium intake was about 940 mg, and in region B about two times lower, i.e., 450 mg/day. The average blood lead concentration was significantly lower in women from region A (69 micrograms/L) than from region B (83 micrograms/L). Our results support the assumption that adequate calcium intake might be one of the preventive measures for decreasing lead absorption. This new evidence, sought for some time by nutritionists and toxicologists, needs further international confirmation.     

Changes in pulmonary Cu−Zn contents in superior mesenteric artery occlusion shock of rabbit

Contents of Cu and Zn of into-pulmonary blood (IPB), out-pulmonary blood (OPB), Lung tissue, and supernatant and macrophages of Lung Lavage were determined in superior mesenteric artery occlusion (SMAO) shock of rabbits. Zn of pulmonary tissue was 11.42 +/- 0.60 and 14.52 +/- 1.78 (micrograms/g wet wt) in SMAO shock and control groups, respectively. Content of Zn was found to be lower, Cu was not changed, and Cu/Zn ratio increased in lung tissue in SMAO shock. Contents of Cu and Zn in other samples were not changed. The results suggest that lower Zn in lung tissue related to acute lung injury.     

Cadmium-induced alterations in ocular trace elements

The present report demonstrates, for the first time, that feeding rats 50 ppm cadmium for just 7 wk results in detectable levels of cadmium in the eye of rats. Furthermore, these ocular cadmium concentrations affect significant alterations in the levels of the essential trace elements selenium, calcium iron, and copper in the eye. Rats were fed a low-selenium (<0.02 ppm selenium), high-copper basal diet (50 ppm copper) supplemented with 0, 0.1, and 0.5 ppm selenium. The animals were either untreated or treated with 50 ppm cadmium admixed with their feed. Cadmium treatment resulted in significant reductions (up to 50%) in ocular selenium. Furthermore, rats fed the basal diet and given 100 ppm cadmium via their feed for 6 wk exhibited a 69% reduction in the activity of the selenoenzyme, glutathione peroxidase, in the eye. Cadmium treatment also resulted in reductions of up to 50% in ocular calcium, irrespective of dietary selenium supplementation. Iron levels were increased by 30% in rats fed the low-selenium diet and decreased by as much as 40% in rats fed the selenium-supplemented diets, compared to animals fed identical levels of selenium without cadmium. Ocular copper levels were significantly increased only in rats fed the low-selenium diet and treated with cadmium. Ocular zinc levels were not significantly affected by dietary cadmium or selenium.     

Effects of etretinate on the distribution of elements in rats

We studied in the rat the effects of the drug etretinate (Tigason), given at three doses 3, 10, and 30 mg/kg body wt for 1 mo, on the concentrations of Na, K, Ca, Mg, Fe, S, P, Cu, and Zn in the plasma, brain, thymus, heart, liver, lung, kidney, testicle, muscle, and bone. The elements were simultaneously determined in tissues after nitric acid dissolution by inductively coupled plasma emission spectrometry using a JY 48 instrument. At the dose of 3 mg/kg, etretinate did not induce any statistically significant modifications of the element distribution. At the dose of 10 mg/kg, the main observed modifications were in plasma an increase of copper (+38%) and a decrease of zinc (-25%). At the highest dose of 30 mg/kg, some variations of the concentrations of elements in tissues were observed. But, on no account did retinoids induce an alteration of the mineral composition of bone, despite obvious macroscopic bone alterations.     

Metabolic deposition of selenium and cadmium into the hair and other tissues of the guinea pig

To better understand the significance of hair trace-element measurements and their relationships with the trace-element levels in body organs and fluids, a series of controlled animal experiments were conducted in which several trace elements were periodically measured during a 90-day chronic exposure to selenium and cadmium. Chronic selenium exposure appeared to be reflected by elevated selenium levels in the hair, kidneys, and liver. Chronic cadmium exposure, although reflected by kidney and liver elevation, appeared not to be reflected by corresponding increases in its concentration in the hair.     

Determination of main and trace element contents in human brain by NAA and ICP-AES methods

A study was undertaken to determine the average values for elements in normal human brain (11 individuals, age group 65–75). Twelve brain parts were selected from both hemispheres. Determinations were carried out by NAA and ICP-AES. The main elements (Na, K, Mg, Ca, Fe, P, S) and trace elements (Al, B, Co, Cr, Cu, Mn, Ni, Pb, Zn) were investigated. Quality control was ensured by using NBS Bovine Liver SRM. The results obtained with independent methods were compared, and the data show a good correlation. On the basis of these investigations, the regional distribution of elements can be given.     

Elemental concentrations in Nigerians with affective disorders using proton-induced X-ray emission

The concentrations of a number of elements are determined in the plasma and erythrocytes of 21 Nigerians (11 females, 10 males) with symptomatic affective disorders (11 depressives, 10 manics) and in 40 normal controls using proton-induced X-ray emission (PIXE) analysis. The study shows that there is significant elevation of plasma K and Zn, as well as the erythrocyte S in the patients relative to the controls. The plasma and erythrocyte Cu, and the erythrocyte P, Ca, Fe, and Zn are significantly lower in the patients compared to the controls. However, the plasma levels of Ca, S, Fe, and Br are similar in both the patients and the controls. Similarly, the concentrations of K, Br, and Rb show no significant difference in the erythrocytes of patients and controls.     

Mercury and selenium distribution in human kidney cortex

Concentration of mercury and selenium were analyzed in tissue fractions of human kidney cortex samples from seven autopsy cases. Total mercury content ranged between 0.3–9.0 nmol Hg/g wet wt. Between 27–61% of the total mercury was found in the 105,000g supernatant of the tissue homogenate from six cases. In kidney cortex from the seventh case, a deceased dentist with the highest concentration of mercury, only 3% of the total mercury was found in the 105,000g supernatant and about 88% in a SDS-insoluble fraction. In this fraction the molar ratio between mercury and selenium was close to 1∶1. This study supports results from previous animal studies and indicates that mercury in human kidney cortex could be deposited in forms with different solubility. It could be of importance to speciate different forms of mercury in tissues according to solubility and association to selenium when interpretations of mercury concentrations are made.     

Enhancement of the kidney Cd burden by SH-containing chelating agents

The accumulation of Cd in the kidneys is enhanced markedly if chelating agents that contain SH-groups like 2,3 dimercaptopropanol (BAL) are injected immediately after the metal. This is not a transient effect but persists for more than 3 d. It is less pronounced at higher chelate doses or when the pH of urine is increased. Our experiments indicate that chelating agents, which form unstable complexes at acid pH and are able to pass through the cell membrane, will cause metal accumulation in the kidneys.     

Decreased thiamine and magnesium levels in the potentiation of the neurotoxicity of lead in occupational lead exposure

The relationship between blood lead (Pb) and serum levels of calcium and of neural nutrients such as thiamine and magnesium (Mg) has been determined in a Nigerian population that is occupationally exposed to Pb. Forty-seven male Pb workers were recruited as test subjects and 25 males unexposed to Pb served as controls. The test subjects were classified into three groups, based on severity of exposure to Pb. Blood lead (BPb) and the serum levels of Mg, thiamine, and calcium were determined in both test subjects and controls. The mean blood Pb level was not significantly higher in Pb workers. In contrast, Mg and thiamine levels were significantly decreased (p<0.05; p<0.01, respectively). However, the calcium level was not significantly lower in test subjects than in controls. Also, there was a significant negative correlation between serum thiamine and blood Pb levels (r=-0.50; p<0.01). Furthermore, there was a significant negative correlation between serum calcium and BPb levels (r=-0.41; p<0.01). This study has shown that relatively low BPb levels can enhance Pb absorption and also potentiate Pb neurotoxicity in the presence of decreased serum thiamine and Mg levels.     

Determination of trace elements in human serum by inductively coupled plasma-mass spectrometry

The determination of trace and ultratrace elements in human serum by ICP-MS is described. The accuracy of the method is tested using a “second generation” human serum reference material. Elements determined include Fe, Co, Cu, Zn, Br, Rb, Sr, Mo, and Cs. The method is compared to nuclear analytical methods (NAA, PIXE). Perspectives for the future are also discussed.