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PubMed2005

Emissions of mercury and other trace elements from coal-fired power plants in Japan.

To evaluate trace element emissions from modern coal-fired power plants into the atmospheric environment in Japan, trace elements in the coal used in electric utility boilers, stack concentrations, emission rates and emission ratios of coal-fired power plants, and proportions of trace elements in coal-fired power plants were studied. The elements were As, B, Be, Cd, Co, Cr, F, Hg, Mn, Ni, Pb, Sb, Se and V, which are designated in the Law of Pollutant Release and Transfer Register. The particulate trace elements were collected in an electrostatic precipitator and a wet desulfurization scrubber. Emissions into the atmosphere were lower than 1% of the quantity in coal, but the volatile trace elements showed somewhat higher emission ratios. For mercury, the mean concentration in coal was 0.045 ppm, the mean emission rate was 4.4 microg/kW h, and the mean emission ratio was 27%, the highest ratio among all elements in this study. The total annual emission of mercury from coal-fired power plants of the electric power industry in Japan was estimated to be 0.63 t/y. On the basis of these data, the atmospheric environment loads from a coal-fired power station were investigated. The calculation of stack gas dispersion showed that maximum annual mean ground level concentrations were in the order of 10(-2) to 10(-5) of the background concentrations, and that the adverse effect of the emissions from the coal-fired power station was small.

Air Pollutants↗
PubMed2004

Trace element changes in sclerotic heart valves from patients are expressed in their blood.

The pathogenesis of some heart diseases has been associated with changes in the balance of certain trace elements. However, whether blood trace element changes exist that are related to changes in the cardiovascular system are, in most cases, unknown. In this study, blood trace element levels were analysed in 46 patients with non-rheumatic aortic valve sclerosis that were previously shown to have a disturbed trace element balance in their valve tissue, including 11/15 elements. Results showed significant changes of blood levels of 8/15 trace elements in these patients when compared with blood levels in 46 healthy controls. Of these elements, Cd and Mg were the only elements that increased in both blood and valves. Cu and Se were increased in blood but decreased in valves, whereas Co and Zn were decreased in blood but increased in valves. Several elements (As, Ca, Fe, Pb, and V) were unchanged in blood although changed in valves. Although Mn and Hg showed changes in blood, this was not evident in the valves. Al and Ag were the only elements that did not change in both blood and valves. Significant covariation in blood and valve levels was only observed for Al and Pb. The recorded pattern of trace element changes indicates a complex competition/exchange between body compartments in this disease, where the increased blood Cu/Zn ratio suggests an ongoing infectious/inflammatory process.

Adult↗
PubMed2002

International legislation on trace elements as contaminants in food: a review.

Environmental contaminants such as trace elements may be present in all foods. Foods, raw materials and ingredients for food production are to an increasing extent traded across borders. Hence, there is a need for international legislation on trace elements as contaminants in food. In 1961, the FAO and WHO established the Codex Alimentarius to elaborate international food legislation. Contaminants in food are handled by the Codex Committee for Food Additives and Contaminants (CCFAC). The Codex Alimentarius system for developing legislation concerning trace elements as contaminants in food is based upon the Codex General Standard for Contaminants and Toxins in Food (GSCTF). By October 2001, the principles for setting maximum limits (MLs) for contaminants in food are agreed, and work is in progress on MLs for trace elements such as lead and cadmium in the various food categories. The status for the proposals is presented and discussed. The EU Regulation 466/2001 of 8 March 2001 sets MLs for lead and cadmium in various foods. This regulation will apply from 5 April 2002. The EU regulation is more detailed but similar to the Codex draft standards for lead and cadmium in food. In future, legislators and administrators in the Codex and EU and analytical chemists will discuss how to use more and better analytical data as risk-management tools to protect public health. Trace elements' speciation is an important aspect of this discussion.

European Union↗
PubMed1996

[Two dimensional imaging and functional evaluation of trace elements on tissues and organs by x-ray spectroscopy].

Trace elemental composition in tissues and organs was investigated to clarify the two dimensional imaging and functional evaluation using x-ray spectroscopy such as non-destruction x-ray analytical microscope (x-ray guide tube 100 microns). Al, Si, P, S, Cl, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, and Br tissues and organs, i.e., bromoderma exfolistiv squama, olfactory epithelium and anthracosis specimens were detected in microscopic area (about 10-25 mm) of the specimens and a fluorescent x-ray analysis of elemental imaging and mapping at the same time. The specimens can be observed in atmospheric pressure. The non-destruction x-ray analytical microscopic technique of trace element in biological tissues and organs was carried out on functional evaluation of trace elements, and it is shown that the technique is a useful analytical technique, which enables the detection of many trace elements simultaneously and provides image, mapping information on the diagnostic analysis of many diseases affecting the joints.

Animals↗
PubMed1996

Trace element concentrations in the fruit peels and trunks of Musa paradisiaca.

Chemical analyses for the elementary compositions of the ashes of the fruit peels and trunks of the tropical plantain Musa paradisiaca have been undertaken. The elements, categorized as trace elements, generally are found to have higher mean concentrations in the fruit peels than in the trunks (except in the case of Zn). Their peel-trunk uptake ratios have been calculated and range between 1 and 4, showing normal levels of accumulations in the fruit peels over the trunks.

Copper↗
PubMedDate not supplied

[Trace element imbalance in children with environmentally induced pathology].

The study examined the balance of trace elements in children with nontoxic goiter and alopecia and attempted to consider these entities in terms of multiple trace element deficiencies. All the children examined children with nontoxic goiter and alopecia were found to have lower concentrations of essential elements (Cu, Zn, Fe) and higher levels of toxic trace elements (Sr, Ni Cr), but more pronounced in children with alopecia. In this connection, it is necessary to further establish a correlation between chronic exposure to environmental trace elements and the levels of trace elements in the biosubstrates (blood, hair) of children living in an industrial town.

Adolescent↗
PubMed1996

[Liver diseases and essential trace elements].

The significance of the biochemical and nutritional roles of trace elements is widely recognized, since metals are found as constituent components of many metalloproteins and metalloenzymes. Some trace elements such as copper act as cofactors against hepatic fibrosis in chronic liver diseases, particularly in the biosynthesis of collagen. As the disease progress from chronic hepatitis to liver cirrhosis, serum calcium, magnesium, phosphorus and zinc concentrations decrease, while the copper concentration increases. In the patients with hepatocellular carcinoma, serum concentrations of trace elements are similar to those of liver cirrhosis. In the patients with acute hepatitis, serum calcium, magnesium and zinc concentrations decrease, while phosphorus, iron and copper concentrations decrease. These trace element abnormalities may reflect such pathological conditions as liver dysfunction, cholestasis, hepatic fibrosis or liver regeneration.

Humans↗
PubMed1999

[Interactions of trace elements during their metabolism].

On the basis of the analysis of the literature data and results of own examinations the following conclusion is made: even practically healthy people can have deficiency of trace elements, and the change of trace elements proportion in a ration can influence essentially homeostasis of trace elements with subsequent damage to body functions. The basic cause of deficiency of trace elements in the body is unbalanced relation of various food components intensifying or inhibiting assimilation of trace elements, inadequate consumption of trace elements and their losses during vital activity.

Adolescent↗
PubMed2004

Role of trace elements zinc, copper and magnesium during pregnancy and its outcome.

Trace element deficiencies have been documented to play an important role in determination of the fetal outcome. Pregnant women in developing countries have been reported to consume diets with a lower density of minerals and vitamins. Deficiencies of trace elements like zinc, copper and magnesium have been implicated in various reproductive events like infertility, pregnancy wastage, congenital anomalies, pregnancy induced hypertension, placental abruption, premature rupture of membranes, still births and low birth weight. The present review article highlights the important of role played by zinc, copper and magnesium during pregnancy and its outcome. The role of individual trace elements and in combination with other trace elements has not been completely documented. There is a need to undertake further studies in this field.

Adolescent↗
PubMed1998

Altered plasma and mucosal concentrations of trace elements and antioxidants in active ulcerative colitis.

BACKGROUND: The production of free radicals is increased in inflammatory bowel disease, and trace elements are crucial components of several antioxidants. Trace elements deficiency may therefore compromise the defense against oxidative damage. The aims of this study were to measure plasma and tissue concentration of trace elements and antioxidants and to relate this to disease activity. METHODS: A 10-ml blood sample and six colonic biopsy specimens were obtained from 24 patients with either active ulcerative colitis or in remission and 10 patients with irritable bowel syndrome for measurement of trace elements and trace element-dependent enzymes. RESULTS: Patients with moderately active disease had significantly lower plasma iron, selenium, and glutathione peroxidase levels than patients in remission and controls, whereas no significant differences were found between the zinc and copper values of patients and controls. Mucosal concentrations of zinc and metallothionein were reduced, whereas iron and glutathione peroxidase concentrations were increased in patients with endoscopically active disease as compared with controls and patients in remission. CONCLUSIONS: Patients with ulcerative colitis have altered plasma and tissue levels of trace elements and antioxidant-related enzymes. The resulting reduced protection against free radicals may contribute to the inflammatory process.

Adult↗
PubMed2002

[Association of p53, PCNA expression and trace element content in esophageal mucosa].

BACKGROUND & OBJECTIVE: There were abnormal changes of trace element in esophageal cancer patient's hair and serum in the high risk area. But it was still unknown that the relationship between p53 and proliferating cell nuclear antigen(PCNA) expression and the trace element content in varied esophageal mucosa. This study was designed to probe the relationship of trace element content and p53 mutation, PCNA expression in esophgeal mucosa. METHODS: Esophageal biopsy specimen of 151 cases were divided into four groups (normal, esophagitis, dysplasia, and early carcinoma). The quantitative determination of trace element was performed was performed by using X-ray energy spectrometry and the detection of PCNA expression and p53 mutation was performed by using S-P immunohistochemistry method. RESULTS: The contents of Zn, Se, Mo, were 1.74 +/- 0.32, 1.53 +/- 0.64, 0.58 +/- 0.21, 0.20 +/- 0.08; 0.15 +/- 0.06, 0.10 +/- 0.03, 0.04 +/- 0.02, 0; 4.73 +/- 1.31, 3.45 +/- 1.19, 3.51 +/- 1.32, 2.51 +/- 1.04; respectively in four groups. There was a significant difference in varied histological typies(P < 0.05). The contents of Cu/Zn, Ni were 0.57 +/- 0.17, 0.89 +/- 0.18, 2.45 +/- 0.48, 2.92 +/- 1.08; 0.45 +/- 0.05, 1.27 +/- 0.11, 2.46 +/- 0.24, 2.58 +/- 0.33; respectively, which increased gradually in pace with upgrade of esophageal lesions, with significant difference (P < 0.05). The postive rates of p53 and PCNA were 0, 46.15%, 100%; 31.19%, 84.62%, 100% respectively in normal esophageal epithelium, dysplasia, and early carcinoma, with significant difference (P < 0.01), and had significant correlation to trace element. CONCLUSION: The content variation of Zn, Se, Mo, Cu, Ni could be possessed of certain effect on p53 mutation and PCNA overexpression of esophageal epithelium in the high risk area.

Adult↗
PubMedDate not supplied

PIXE determination of essential trace elements in some traditional Chinese medicines.

The essential trace elements in 30 traditional Chinese medicines, (24 tonics and 6 nontonics) were determined by proton-induced X-ray emission. The authors' previous suggestion that traditional Chinese medicines may be classified by the order of magnitude of their essential trace elements, thus indicating their pharmacological effects, is not justified. The pharmacological effect of a trace element or its essentiality may be dependent on some ligand that can be chelated with it. A nonlinear mapping algorithm, however, shows that the 30 traditional Chinese medicines are nearly separated into two groups, indicating their tonic or nontonic pharmacological effects.

Drugs, Chinese Herbal↗
PubMed1983

Relationship between trace element concentrations in human blood and atmospheric aerosol.

Trace element concentrations in human blood from the U.K., measured by Hamilton et al., are found to be correlated to those of atmospheric aerosol from the U.K., or to an aerosol composition averaged over the globe. The correlation to aerosol is much stronger than to crustal rock or sea water. Elemental enrichment factors for blood are all equal to or greater than those for aerosol. Two possible reasons for the correlation are advanced: aerosol is probably a major source of the trace elements which enter the food chain, and aerosol samples the earth's surface where the food chain originates. The present finding suggests that aerosol plays a major role in the global cycling of the trace elements which enter the blood, with important implications for human health.

Aerosols↗
PubMed1990

Trace elements in drug addicts.

We studied trace elements (zinc, copper, magnesium, iron, and lithium) by atomic absorption spectrophotometry in the plasma and erythrocytes of 120 subjects: 20 healthy controls and 100 parenteral drug addicts (69 heroin and 31 heroin + other drugs). Plasma Zn and intraerythrocytic Zn and Fe were decreased, whereas plasma and intraerythrocytic Cu were significantly increased in the group of drug addicts with respect to the healthy controls. Moreover, a period of abstinence longer than 10 days was associated with lower plasma levels of Zn and Li in subjects who had taken drugs shortly before they were examined. The presence of serological markers against HBV and HIV did not seem to influence the behavior of the trace elements in blood.

Adolescent↗
PubMedDate not supplied

Zinc, copper, manganese, and iron balance of parenterally fed very low birth weight preterm infants receiving a trace element supplement.

To evaluate a pediatric trace element supplement (Ped-El, Pharmacia) 18 metabolic balance studies were completed in 13 infants (mean birth weight 909 +/- 67 g, x +/- SEM; mean gestational age 27.2 +/- 1 weeks) who received total parenteral nutrition. The supplement supplied 40 micrograms/kg/day of zinc resulting in negative retention of 226 micrograms/kg/day. Copper infused at 20 micrograms/kg/day led to a positive retention of 8 micrograms/kg/day and an increase in serum Cu (p less than 0.05) not related to Cu intakes. Manganese infused at 40 micrograms/kg/day was nearly all retained (88 +/- 16% retention). Iron infused at 120 micrograms/kg/day led to a positive retention of 93 micrograms/kg/day. Although plasma ferritin and percent transferrin saturation were elevated, only plasma Fe values were correlated with Fe intake. This trace element supplement does not appear suitable for very low birth weight preterm infants.

Copper↗
PubMed1997

Trace element status of hemodialyzed patients.

The trace elements Ba, Bi, Cd, Co, Cs, Cu, Hg, La, Mn, Mo, Pb, Rb, Sb, Sn, Sr, Tl, and Zn were determined by inductively coupled plasma mass spectrometry in plasma samples of 68 hemodialysis patients. The same elements (with exception of La and Mn) were also determined in whole blood after mineralization with high-purity nitric acid/hydrogen peroxide in a closed-pressurized microwave system. The accuracy and precision was checked by analyzing two Seronorm "whole blood" reference materials. All samples were contaminated with barium (heparinized tubes) and the plasma samples with tin (collection tubes). The concentrations for Bi, Hg, Pb, Rb, Sb, and Sr in whole blood were within the literature ranges for healthy adults. All of the concentrations for Co, and some of the concentrations for Cd, Cs, Tl, and Zn were higher than the high limits of the normal ranges. Approximately 14% of the Cu concentrations were lower than the low limit of the normal range. The Mo and Sn concentrations are difficult to evaluate, because the normal ranges appears to be unreliable. All concentrations for Cd, Co, Mo, Pb, Sn, and Sr and some of the concentrations for Cu (15%) and Mn (75%) in the plasma samples were higher than the high limits of the normal ranges. The concentrations for Rb tended to be lower than the normal range. To establish unequivocally the causes for elevated and reduced concentrations of trace elements in whole blood and plasma of dialysis patients, all fluids in the dialysis process must be investigated.

Adult↗
PubMed1978

Trace elements in kidney stones from three areas in the United States.

A large number of trace elements has been found in calcium stones (whewellite, weddellite, and apatite) and in struvite. Significantly fewer elements, with lower abundances, are found in uric acid and cystine. With the exception of four trace elements (lead, silicon, strontium, and zine), the trace element assemblages are identical in the oxalates (whewellite and weddellite); struvite is also similar but with notable exceptions. In general, apatite contains approximately twice the level of trace element abundances as do the oxalates. This study is based on the distribution of 20 elements in 186 mimeralogically identified urinary calculi from three generalized areas of the United States (northeast, southeast, and midwest). In general, there is no statistical difference in the trace element assemblages of mineralogically identical stones from the three areas.

Aluminum↗