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PubMed1991

A general multiple-compartment model for the transport of trace elements through animals.

Multiple-compartment models employed in the analysis of trace element transport in animals are often based on linear differential equations which relate the rate of change of contaminant (or contaminant concentration) in each compartment to the amount of contaminant (or contaminant concentration) in every other compartment in the system. This has the serious disadvantage of mixing intrinsic physiological properties with the geometry of the animal. The basic equations on which the model presented here is developed are derived from the actual physical process under way and are capable of separating intrinsic physiological properties from geometry. It is thus expected that rate coefficients determined through this model will be applicable to a wider category of physiologically similar animals. A specific application of the model for the study of contamination of sheep--or indeed for any ruminant--is presented, and the temporal evolution of contaminant concentration in the various compartments of the animal is calculated. The application of this model to a system of compartments with changing geometry is also presented.

Animals↗
PubMed2006

Total and partial digestion of sediments for the evaluation of trace element environmental pollution.

Four different sample treatment methods for the determination of trace elements have been compared: a total digestion with HNO3-H2O2-HF using microwave, and three different standardized methods of fractionation: BCR three-steps sequential extraction, USEPA standard 3050B and ISO standard 11466. The four treatment methods were applied to the determination of Cu and Ni in four samples collected in different areas of Cienfuegos Bay (Cuba). The location of samples and the analytes were selected on the basis of results obtained by previous studies. Analyses following total digestion and BCR three-steps procedure were performed by inductively coupled plasma mass spectroscopy whereas analyses following EPA and ISO procedures were performed by flame atomic absorption spectroscopy. The results obtained have been compared with an estimated anthropic fraction evaluated in each sampling point as the difference between the total concentration and an estimated background concentration level. The BCR three-steps provided the best approximation of the estimated anthropic fraction and was therefore applied also in the determination of Pb and Cd for further consideration.

Cadmium↗
PubMed2004

Posidonia oceanica as a biomonitor of trace elements in the Gulf of Naples: temporal trends by lepidochronology.

Levels of Hg, Cd, Pb, Cu, Zn, Fe, and Mn were assessed by using Posidonia oceanica as a bioindicator in the Gulf of Naples (southern Italy). Lepidochronology, which enables retroactive dating of scales and rhizomes of this seagrass, was combined with atomic spectrometry to assess temporal trends of trace elements in dated scales and rhizomes over a 10-year period. Lepidochronology occasionally has been used to monitor Hg in dated scales, but never has been used to determine concentrations of other trace elements in dated rhizomes. Data were compared between various structural parts of seagrass and between sampling sites. Concentrations of some elements found in dated scales or rhizomes showed a similar trend in most of the sites; increasing for Hg and Cu and decreasing for Pb, Fe, and Zn. Contaminant levels indicated by seagrass meadows varied from metal to metal. Concentrations of Hg, Cd, and Pb fell within the ranges measured in other areas considered to have low levels of heavy metal pollution, whereas Cu, Mn, and Zn had higher concentrations only in some years. However, on the basis of other studies, none of the sampling sites are considered to have high contamination levels.

Age Factors↗
PubMed1977

Trace elements (zinc, cobalt, selenium, rubidium, bromine, gold) in human placenta and newborn liver at birth.

Concentrations of zinc, cobalt, selenium, rubidium, bromium, and gold have been determined by neutron activation analysis in 18 placental and 6 liver tissue samples at birth. Their respective mean concentrations +/- standard deviations (parts per million) were 58 +/- 10, 0.060 +/- 0.036, 1.90 +/- 0.41, 14.0 +/- 3.5, 26.9 +/- 14.3, and 0.31 +/- 0.14 in placenta, and 651 +/- 257, 0.156 +/- 0.077, 4.52 +/- 1.96, 9.2 +/- 3.7,11.2 +/- 4.1, and 0.12 +/- 0.06 in liver tissue. Thus, we observed that the mean concentrations of essential trace elements (zinc, cobalt, and selenium) were significantly higher in liver than in placenta, whereas the nonessential trace elements (rubidium, bromium, and gold) were found in significantly higher concentrations in placenta than in liver tissue.

Bromine↗
PubMed2004

Concentrations of trace elements in muscle of sturgeons in the Caspian Sea.

Concentrations of 21 trace elements were determined in muscle of beluga (Huso huso), Persian sturgeon (Acipenser persicus), Russian sturgeon (Acipenser gueldenstaedtii), ship sturgeon (Acipenser nudiventris) and stellate sturgeon (Acipenser stellatus) collected from coastal regions of Azerbaijan, Iran, Kazakhstan and Turkmenistan, surrounding the Caspian Sea during 2000-2001. Concentrations of Mn, Co, Cu, Mo, Sn, Hg, Pb and Bi in the muscle were apparently different among the five species of sturgeons. Especially, beluga showed the highest concentrations of Hg, Pb and Mn in all the five species. In addition, more than half of the individuals of beluga exceeded the guideline level (0.3 microg/g wet wt.) of Hg for food in UK. However, V, Cr, Zn, Ga, Rb, Sr and Ba concentrations were similar among five sturgeons. Growth-dependent increase in Hg in beluga, Cu in Persian sturgeon, and Zn in Russian sturgeon were observed, whereas V, Mn, Co, Cu, Ga, Sr, Mo, Sn, Hg and Bi concentrations in Persian sturgeon, Pb in ship sturgeon, and Cr, Mn, and Rb in stellate sturgeon were negatively correlated with body length. All species of sturgeon in Azerbaijan showed the highest concentration of Sr and the lowest concentration of Rb, while the five sturgeons from Iran showed opposite trends. Concentration of V, which is present in oil, in sturgeons in the Caspian Sea was considerably lower than that of fish from Kuwait, but was comparable to that of Cambodia and the Gulf and Gulf of Oman. To our knowledge, this study provides the first extensive data on multielemental accumulation in sturgeons of the Caspian Sea.

Animals↗
PubMedDate not supplied

[Lipid peroxidation and the trace element content of the blood in patients with lichen ruber planus of the oral mucosa].

Examinations of 143 patients with lichen planus of the buccal mucosa and of 45 normal subjects included studies of lipid peroxidation (LPO) activity and of anti-radical defence system, as well as measurements of a number of blood trace elements. Plasma and red cell LPO intensity in the patients was several times higher than in the controls. Plasma glutathione peroxidase activity was found essentially reduced in the patients, whereas in red cells this activity surpassed 5 times the normal values. Glutathione reductase plasma activity was elevated and its red cell activity decreased. These findings indicate significant LPO disorders in the patients with lichen planus; their blood trace element levels were also found changed.

Adult↗
PubMed2004

A model for evaluation of the phytoavailability of trace elements to vegetables under the field conditions.

Currently, several single extraction methods are used for the evaluation of the phytoavailability of metals using pot experiments. A systematic comparison, however, is lacking. It is especially true for the field studies. This study was to investigate the phytoavailability of trace elements to vegetables grown on metal-contaminated soils under the field conditions. All soils collected were typical calcareous soils in northern China. Four frequently used methods using CaCl2, diethylenetriaminepentaacetic acid (DTPA), CH3COOH, and water as extractants were compared for phyto-availability. The concentrations of metals extracted by these four extraction methods ranged from 3.42 to 815, 1.51- 6965, 0.732-24473, 0.688-7863, 0.246-685, 1.99-5337 0.203-4649 ng/g for Cr, Ni, Zn, Cu, Cd, Pb and REEs, respectively. Simple correlation analysis indicated that a significant correlation (Cr: r = 0.5411**; Zn: r = 0.6352**; Cd: r = 0.6979**; Pb: r = 0.5537** and REEs: r = 0.5185** -0.6684**) was observed between the CaCl2-extractable metals in soil solution and that in Chinese cabbage. In addition, soil pH, organic matter (OM), and cation exchange capacity (CEC) also affect the phytoavailability. An empirical model was developed to express the combined effect of soil properties on the phytoavailability. The stepwise multiple regression analysis demonstrated that the phytoavailability of trace elements strongly correlated with the extractable fraction by CaCl2, total metal concentration in soils, and soil pH, OM, CEC. This model can describe approximately 75-95% of the variability of metal uptake and the r2 values ranged from 0.741** to 0.954**, which were much better than the single correlation analysis. For celery and cole, a strong correlation was obtained for Cr, Ni, Zn, Cu, Cd, La, Ce, Pr and Nd. For spinach and Chinese cabbage, however, a positive correlation was only observed for 1 and 3 metals, respectively. Generally, the developed empirical model can integrate the combined effects of soil properties, extractable metal fractions in soil solutions and plant species on the phytoavailability of metals to vegetables in the field conditions.

Biological Availability↗
PubMed2004

Alterations in plasma essential trace elements selenium, manganese, zinc, copper, and iron concentrations and the possible role of these elements on oxidative status in patients with childhood asthma.

The aim of the present study is to evaluate the status of plasma essential trace element selenium (Se), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) concentrations and the effect of these elements on oxidative status in patients with childhood asthma. Plasma Se, Mn, Cu, and Zn concentrations were determined by atomic absorption spectrophotometry (AAS) and Fe concentrations, malondialdehyde (MDA), and total antioxidant capacity (TAC) were determined by the colorimetric method. The plasma MDA/TAC ratio was calculated as an index of oxidative status. Plasma albumin levels were measured to determine nutritional status. Plasma Fe concentrations, MDA levels and the MDA/TAC ratio were significantly higher (p<0.001, p<0.001, and p<0.01, respectively) and Se and Mn concentrations and TAC were lower (p<0.01, p<0.05, and p<0.01, respectively) in patients when compared to the healthy subjects. Plasma Zn, Cu, and albumin levels were not found to be significantly different in patients and controls (p>0.05). There were positive relationships between plasma MDA and Fe (r=0.545, p<0.001) and TAC and Se (r= 0.485, p<0.021), and a negative correlation between TAC and MDA values (r= -0.337, p<0.031) in patients with childhood asthma. However, there was no correlation between these trace elements and albumin content in patient groups. These observations suggest that increased Fe and decreased Se concentrations in patients with childhood asthma may be responsible for the oxidant/antioxidant imbalance.

Adolescent↗
PubMed2002

Trace element status and early physical growth of exclusively breastfed normal and asphyxiated Nigerian babies.

Serial anthropometry and assay of plasma iron (Fe), zinc (Zn) and copper (Cu) were done on 72 babies with birth asphyxia during the first six months of life to assess the pattern of their physical growth and trace element status, respectively. Eighty-seven non-asphyxiated babies served as controls. The mothers of babies in both groups also had their plasma assayed for Fe, Zn and Cu immediately following delivery. Asphyxiated babies were lighter than non-asphyxiated controls during the first two months of life and they also had smaller mean occipito-frontal circumference at birth. While Fe, Zn and Cu status was generally comparable in both groups, the newborn Cu concentrations were very low compared with earlier reports. No baby showed any overt signs of trace element deficiency.

Apgar Score↗
PubMed2006

Dietary mineral and trace element intake and squamous cell carcinoma of the esophagus in a Chinese population.

Few studies have been conducted in low-selenium areas of China to assess the relationships between dietary intake of selenium and zinc and the risk of squamous cell carcinoma of the esophagus (SCCE). We studied dietary mineral and trace element intake and risk of SCCE in a population- based, case-control study in Taixing, China, in 2000. A total of 218 SCCE patients and 415 population healthy controls were interviewed using a standard dietary and health questionnaire. The median and quartiles were calculated to represent the average level and distribution of selected dietary minerals and trace elements estimated by the Chinese Standard Tables of Food Composition. The adjusted odds ratios (ORs) comparing the highest with the lowest quartiles were 0.30 (95% confidence intervals, CIs = 0.13-0.67) for selenium intake and 0.28 (95% CI = 0.11-0.70) for zinc intake with obvious dose-dependent patterns (P values for trend = 0.01). The adjusted OR for the combined effect of selenium and zinc intake was 0.53 (95% CI = 0.29-0.96) after controlling for potential confounding factors, including age, gender, educational level, body mass index, and total energy intake. Our results suggested that the potential joint effect of zinc and selenium might contribute to SCCE risk. Increased dietary intake of selenium and zinc may decrease the risk of SCCE in a low-selenium area of China.

Aged↗
PubMed1985

Grace A. Goldsmith Award lecture. Trace element regulation of immunity and infection.

Protein-calorie malnutrition is associated with impaired immunocompetence and increased susceptibility to infection. Clinically evident nutritional deficiency syndromes, however, are composite of deficits of many essential nutrients, each of which may exert an important regulating effect on immunity. Among other nutrients, several trace elements have been shown to regulate immune responses, particularly cell-mediated immunity. Zinc undernutrition results in lymphoid atrophy and reduced capacity to respond to many T-cell-dependent antigens. Plaque forming cell response to heterologous erythrocytes is decreased, as is the function of B cells. In zinc deficient rodents, the generation of cytotoxic lymphocytes in the spleen is reduced. Antibody-dependent cell-mediated cytotoxicity is largely unchanged. In acrodermatitis enteropathica, lymphocyte proliferation response to mitogens is decreased and there are significant changes in delayed hypersensitivity responses and in the proportion of various T cell subsets. Neutrophil function is not changed by zinc deficiency. Iron deficiency results in a slight decrease in the number of rosette-forming T cells and a significant impairment of lymphocyte response to mitogens and antigens. Polymorphonuclear leukocytes are unable to kill ingested bacteria and fungi in an efficient manner. Copper deficiency impairs cell-mediated immunity, as does selenium deficiency when it is associated with vitamin E lack. Several pathogenetic mechanisms may underlie such alterations in immunity. Many heavy metals impair immune responses. These effects of trace elements on immunity may have important fundamental and practical implications.

Animals↗
PubMed2005

Hepatic and renal concentrations of 10 trace elements in crocodiles (Crocodylus niloticus) in the Kafue and Luangwa rivers in Zambia.

Hepatic and renal concentrations of the elements arsenic, cadmium, cobalt, copper, lead, manganese, mercury, molybdenum, selenium and zinc were determined in samples collected from four crocodiles from the Kafue River, Kafue National Park and five crocodiles from the Luangwa River, Luangwa National Park, Zambia. The concentrations of the essential elements were similar to those reported in other vertebrates. Arsenic and cadmium concentrations were low (medians below 0.05 microg As/g and below 0.16 microg Cd/g, wet wt.). Mercury and lead concentrations were several orders of magnitude higher (medians up to 3.7 microg Hg/g, and up to 8.7 microg Pb/g, all wet wt.) than in hippopotami from the same rivers, probably as a result of food-chain biomagnification. Judging by the results obtained in this study, pollution from the mining activity around the Kafue River drainage area in the Copperbelt region has not significantly influenced the trace element concentrations in tissues of the crocodiles in the Kafue National Park. The trace element concentrations measured may serve as reference values in future studies on crocodilians.

Alligators and Crocodiles↗
PubMed2001

Trends in certified reference materials for the speciation of trace elements.

The measurement of the chemical species of elements (instead of the total element concentration) has become an irreversible trend in analytical chemistry. The motivation lies in the fact that the biochemical and geochemical behaviour of an element is governed by its species. Quality assurance of the analytical procedures used for speciation analysis requires the analysis of representative reference materials, certified for the relevant species. Up to now the number of existing certified reference materials for trace element species is very limited. The most important ones are environmental CRMs certified for trialkyltin compounds, methylmercury, Cr(III)/Cr(VI) and food CRMs certified for arsenic species and methylmercury. Major developments are to be expected in CRMs focussed on environmental problems, including waste treatment, on bioavailability of trace elements in food and on bio-monitoring in occupational health and hygiene. It is, however, unlikely that the producers of CRMs will ever be able to cover all needs. Add to this that many, very active species are notoriously unstable and/or short living and require in-situ analysis. This will lead to different analytical developments, such as analyses in-situ, where the classical concept of CRMs may not stand firm anymore.

Animals↗
PubMed1996

Preliminary report of trace elements in mothers and newborns living in the Kola Peninsula and Arkhangelsk region of Russia compared to Norwegian populations.

Recently, considerable attention has been allotted to the possible health effects of the industrial pollution in the regions adjoining the Norwegian-Russian border. As a measure of general health, the status of trace elements and some clinical-chemical parameters in serum and blood that reflect general health was assessed for 50 consecutive obstetric patients presenting at delivery departments of local hospitals in the Kola Peninsula, Arkhangelsk and selected centres in Norway. A written questionnaire and consent form were completed by each participant. Specimens of maternal and cord blood were collected. Corresponding samples were analyzed for copper, zinc, selenium, iron and ferritin. We found a lower birth weight in the Russian centres. The measurement of trace elements showed a higher iron status for the Russian females and relatively low serum zinc levels were observed in both the Russian and the Norwegian communities. It may be concluded that with the exception of zinc, the mineral status in the Norwegian and Russian arctic centres considered appears to be satisfactory.

Arctic Regions↗
PubMed1994

Effect of radiodetoxified endotoxin and trace elements on reticulo-endothelial system damaged by ethanol in rats.

For the demonstration of RES activity 99-mTc labelled nano-albumon micro-colloid solution (prepared by OSSKI, Budapest, Hungary) was injected into the prepared jugular vein of narcotized rats and the clearance rate was investigated. The effects of various materials have been observed on RES in vivo. Continuous consumption of 20% ethanol solution for 15 weeks decreased the phagocytic activity. One hundred microgram/100 g body weight (i.v.) of the radio-detoxified endotoxin preparation (RD-LPS, TOLERIN) prepared from Escherichia coli endotoxin by 60Co-gamma irradiation (150 KGy) increased the granulopectic activity of RES of intoxicated animals. The preparation containing trace elements also increased the former activity and the treatment consisting of the use of both trace elements and RD-LPD was as effective as the RD-LPD per sc.

Animals↗
PubMed1986

Biological monitoring of environmental pollution and human exposure to some trace elements.

The extent of environmental pollution and resulting human exposure to hazardous toxic chemicals in the environment is often difficult to assess. One of the possible alternative approaches to this problem is the use of the biological indicators to demonstrate environmental pollution. This approach appears to be particularly suitable for demonstrating exposure to potentially toxic trace elements. In addition to analyses of plant and animal specimens the element content of human hair as an indicator of exposures to arsenic, mercury, cadmium, lead, antimony, manganese, nickel and cobalt has been repeatedly confirmed as reliable, provided the analyses were carried out and evaluated on group diagnostic basis and were done in groups of individuals occupationally not exposed to these metals. Preferably groups of 10-year-old children are to be used when only environmental pollution is to be taken into account. Hair samples are incomparably easier to collect, transport and store than the alternative biological material such as blood and urine used commonly to demonstrate exposure to various toxic agents. Biological monitoring of environmental pollution cannot replace the standard procedures of measuring air, water and soil pollution; however, the technique appears to have the potential of being an effective tool search for the extent of environmental pollution and for delimitation of territorial boundaries of areas affected most by hazardous emissions containing potentially toxic trace elements.

Activation Analysis↗
PubMed1990

[Morphological evaluation and analysis of trace elements in the liver of rats who were fed with feed containing power station ashes].

The experiment was carried out on white Wistar rats. The rats in the experimental groups received fodder containing power station ashes for various periods of time (from 6 to 18 weeks). During the experiment, the body weight of rats was recorded, the amount of trace elements in the liver was estimated, and morphological tests of the liver were carried out. The results of these experiments indicate that feeding the rats on fodder containing power station ashes causes several percent increase in the body weight and slight differences in accumulation of trace elements. Morphological changes in the liver are connected with the vacuolization of the hepatocytes' cytoplasma and an increase in the amount of phagocytic cells in hepatic sinuses. The intensity of morphological changes was correlated with the time of experiment.

Animal Feed↗
PubMed2006

Treatment of acid mine drainage with fly ash: removal of major contaminants and trace elements.

Acid mine drainage (AMD) has been reacted with two South African fly ashes in a batch setup in an attempt to evaluate their neutralization and major, trace elements removal capacity. Different fly ash: acid mine drainage ratios (FA: AMD) were stirred in a beaker for a set time and the process water analyzed for major, trace elements and sulphate content. The three factors that finally dictated the nature of the final solution in these neutralization reactions were the FA: AMD ratio, the contact time of the reaction and the chemistry of the AMD. Efficiency of the elements removal was directly linked to the amount of FA in the reaction mixture and to the final pH attained. Most elements attained approximately 100% removal only when the pH of minimum solubility of their hydroxides was achieved (i.e., Mg = 10.49-11.0, Cu(2+) = 6, Pb(2+) = 6-7). Dissolution of CaO and subsequent precipitation of gypsum and formation of Al, Fe oxyhydroxysulphates, Fe oxyhydroxides with subsequent adsorption of sulphate contributed to the sulphate attenuation. Significant leaching of B, Sr, Ba and Mo was observed as the reaction progressed and was observed to increase with quantity of fly ash in the reaction mixture. However B was observed to decrease at high FA: AMD ratios probably as result of co-precipitation with CaCO(3(s)).

Acids↗