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Trace elements in major solid-pesticides used in the Gaza Strip.

This study describes the purity of pesticides used in Gaza in terms of trace elements. A semi-quantitative EMMA-XRF technique and quantitative ICP/OES was used to determine the concentrations of Al, As, Ba, Br, Ca, Cd, Co, Cr, Cu, Fe, K, Mn, Ni, Pb, Rb, Sc, Se, Sr, Ti and Zn in 50 of the most commonly used solid pesticides collected from the five central shops in the Gaza Strip. The results revealed that the pesticides contain considerable amounts of trace elements and do not comply with the expected-theoretical structure of each species. Moreover, they do not reflect the actual constituents mentioned in the trade labels. Interviews with market owners and field surveys confirmed that the pesticides were not pure. In some cases they have been mixed in local markets with minor inorganic species without a scientific basis. They may also have been smuggled into Gaza with differing impurities. The results indicate that pesticides should be considered as a source of certain trace metals (particularly Cu, Mn and Zn) and other elements (Br, Sr and Ti), which may affect their mass balances in soil and groundwater as well as their plant uptake. Different scenarios and calculation models of the transport of trace elements in soil and groundwater of the Gaza Strip should include pesticides as an additional source.

Environmental Monitoring↗

Trace element concentration in human brain. Activation analysis of cobalt, iron, rubidium, selenium, zinc, chromium, silver, cesium, antimony and scandium.

Up to 60 tissue samples were dissected from 13 human brains in defined regions and were analysed by means of neutron activation analysis for trace element concentration of cobalt, iron, rubidium, selesium, zinc, chromium, silver, cesium, antimony and scandium. It was shown that the variation in concentration of the non-essential elements in the different brain regions was greater than the corresponding variations in concentration of the essential elements. The mean values of Fe and Rb concentrations were higher in the basal ganglia than in the cortex areas. With increasing age the Fe concentration in the human brain was found to increase and that of Rb to decrease. Comparison of the trace element concentration in corresponding areas of the right and left hemispheres showed highly significant positive correlations for the essential elements. The concentration of each of the essential elements Fe, Rb and Zn was also found to differ significantly between defined functional regions. The characteristic distribution of essential trace elements in different areas is discussed in the light of known metabolic functions of these elements.

Adult↗

Assessment of vitamin and trace element supplementation in severely burned patients undergoing long-term parenteral and enteral nutrition.

The efficacy of an oral supplement of vitamins and trace elements during a longterm artificial parenteral and enteral nutrition was investigated for 3 months in patients with extensive burns. Thirty severely burned patients (22 male, 8 female, age 41 +/- 18 years, range 23-59 years, 33 +/- 12% total body surface area burn, 22% +/- 8 full thickness burn surface area) were included. Every 10 days, from day 10 until day 90, we determined serum levels of: *vitamins B1, B12, A, E, *folic acid, *copper, zinc, iron, *transferrin, albumin, prealbumin, total proteins, *fibronectin, retinol binding protein (RBP), *calcium, *phosphorus, *triglycerides, *total cholesterol, *C reactive protein (CRP), *erythrocyte folic acid. The mean daily nutritional support was 60 Kcals and 0.4 g N per kg of body weight, 70% enterally and 30% parenterally administered, with enteral vitamin and trace element supplementation. On day 10, there was a decrease of the serum level of 19/20 parameters. For 8 parameters (vitamin A, total cholesterol, iron, transferrin, fibronectin, phosphorus, RBP, total proteins), the level was lower than usual. Between day 10 and day 20, a significant normalization of 6 of them was noted, the average levels of transferrin and iron remaining below normal values until day 50. There was a significant decrease in C-reactive protein levels, however above normal limits. No deficiency in vitamins or trace elements was found. Cyclic variations of serum levels occurred which may be more related to volemic, hydroelectrolytic, endocrine and inflammatory disorders than to nutritional problems.

Journal Article↗

Mass balance of trace elements in Walker branch watershed: relation to coal-fired steam plants.

A mass balance study of trace element flows at the TVA Allen Steam Plant at Memphis showed that most of the released Hg, some Se, and probably most Cl and Br are discharged to the atmosphere as gases. The elements As, Cd, Cu, Ga, Mo, Pb, Sb, Se, and Zn were concentrated in fly ash compared to slag and were more concentrated in the ash discharged through the stack than in that collected by the precipitator, while Al, Ba, Ca, Ce, Co, Eu, Fe, Hf, K, La, Mg, Mn, Rb, Sm, Sr, Ta, Th, and Ti showed little preferential partitioning between the slag and the collected or discharged fly ash. The elements Cr, Cs, Na, Ni, U, and V exhibited behavior intermediate between the latter two groups. This information about stack emissions of trace elements from the Allen Plant was used to estimate the likely range of air concentrations and input (dry and wet deposition) to the Walker Branch Watershed. The watershed, which is on the ERDA reservation at Oak Ridge, is within 20 km of three coal-fired steam plants, two in the TVA system and one belonging to ERDA. The estimated input values are compared to measurements of Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn in wet precipitation falling on the watershed during 1973 and 1974. Dry deposition of these elements could not be measured directly but estimates indicated that this could be of the same order of magnitude as the rainwater input. A six-month mass balance indicated that the watershed efficiently retains Pb (97-98% of the atmospheric input,) Cu (82-84%), while Cr (69%), Mn (57%), Zn (73%), and Hg (69%) are less well retained.

Air↗

Distribution of trace elements in the lipid and nonlipid matter of hair.

We studied the effect of lipid removal on the concentrations of 13 trace elements measured in human hair. We used a pooled specimen of hair from a barber shop, initially washed with de-ionized water, with ultrasonic cleaning, then analyzed for Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Si, Sr, and Zn with use of an inductively coupled plasma emission spectrometer. The lipid was removed by Soxhlet extraction with ethanol, and the hair was re-analyzed. We found several elements present in a relatively large proportion (greater than 20%) in the lipid fraction, mainly Na, K, Ca, Mg, Ni, and Sr. We suggest that removal of part or all of the lipids from hair by using detergents or other lipid-removing solvents for washing may account for the variability in data on elements in hair reported by different laboratories, and that those elements largely present in the lipid fraction are the result of environmental exposure, whereas those retained in the hair fiber after lipid removal can be attributed to nutritional and clinical aspects. We believe that such determination of the distribution of elements may help validate the use of hair in assessing trace elements in the body.

Adult↗

[Spectrometric determination of trace elements in pagoda flower].

The twelve trace elements in the pagoda flower, including K, Na, Ca, Mg, Pb, Cd, Cu, Mn, Co, Zn, Cr and Fe were determined simultaneously by FAAS. The relative standard deviation of the method is 0.07%-2.31%, and the recovery is 97.0%-107.0%. The analytical results were satisfactory. The results showed that there were comparatively rich metal elements in the pagoda flower. Proportions of the twelve elements are in the order that K > Ca > Mg > Na > Fe > Zn > Cu > Mn > Co > Pb > Cr > Cd. It implied that the nutritive value of the pagoda flower is high.

Clerodendrum↗

Zinc and other trace elements in liver cirrhosis.

Alterations in trace element concentrations may be observed in patients with chronic liver disease. Notably, selenium and zinc levels are reduced both in serum and in liver tissue of cirrhotic patients. Low selenium levels have been involved in the pathogenesis of liver damage as this element is important in controlling the levels of toxic oxygen radicals in the cells. Zinc deficiency has been involved in the pathogenesis of a number of clinical findings in chronic liver disease. These include the possible role of zinc deficiency in the pathogenesis of hepatic encephalopathy, by inducing alterations in urea metabolism. In CC14 cirrhotic rats oral zinc supplementation reduces ammonia levels and increases OCT activity in the liver. Oral zinc supplementation has been also proposed in the treatment of cirrhotic patients with chronic hepatic encephalopathy, the results however are not yet conclusive.

Humans↗

[Prolonged pregnancy and trace elements: iron].

Iron is an essential trace element and it is well known that the iron requirement steadily increase during pregnancy. The aim of this investigation was to compare the serum iron levels in normal and serotine pregnancy. Twenty-six women with serotine pregnancy (19 in 42 and 7 in 43 gestation week (g.w.)) were included in the study. The control group is consisted from 74 women with normal pregnancy. The serum iron concentration is elevated in the women with serotine pregnancy (24.59 +/- 11.60 mmol/(l), but the difference was not significant. The group with serotine pregnancy in 42 g.w. has even lower serum iron concentration than the women with normal pregnancy (19.44 +/- 6.52 mmol(l). The serum iron concentration was significantly elevated (p < 0.001) in serotine pregnancy in 43 g.w. compared with normal pregnancy as well as with serotine pregnancy in 43 g.w. The possible pathogenetic mechanisms of the observed changes are discussed.

Analysis of Variance↗

Assessment of nutritional status and trace element contamination of holm oak woodlands through analyses of leaves and surrounding soils.

The nutritional status and trace element contamination of holm oak woodlands in Vesuvius National Park were assessed by analyses of Quercus ilex L. leaves and surrounding soils. The concentrations of Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V and Zn were measured in 1-year-old leaves, and in the soils at 0-5 and 15-20 cm depths. The potentially available concentrations were also measured for the soils. The leaf element concentrations were similar to the Q. ilex chemical fingerprint, thus indicating a good nutritional status and the absence of short-term trace element depositions. Total K and V were more abundant in the deep soil layers than in the surface ones, whereas Cd and Pb showed higher values in the surface soils. This suggests that long-term soil accumulations of Cd and Pb are due to atmospheric input. The soil availabilities of Cd, Pb and Zn were high, and Cr availability was very low. A correlation between the available concentrations in the deep soil layers and leaf concentrations was found only for Zn.

Metals, Heavy↗

Trace element distribution in growing feathers: additional excretion in feather sheaths.

The use of feathers is a non-invasive and repeatable method for biomonitoring trace element levels in birds and their ecosystems. Trace element levels were examined in different parts of growing flight feathers from young common terns (Sterna hirundo) to determine distribution of heavy metals and selenium, potential bias from using partially grown feathers, and whether additional heavy metals and selenium are excreted in feather sheaths that are sloughed before feathers are usually sampled. Lead and mercury levels were significantly higher in the distal fully formed portion of the growing feather (with no residual blood supply) compared to the proximal, growing portion of the feather with a residual blood supply, but no significant differences were evident for cadmium and selenium. These results suggest that using partially grown feathers underestimates the amount of lead and mercury in fully formed feathers and that higher levels of lead and mercury are sequestered in feathers than are present in the blood at any one time. Significantly higher concentrations of lead and cadmium, and significantly lower levels of mercury were in the sheath compared to the whole feather blade. These data suggest that birds excrete more lead and cadmium during molt than previously thought.

Animals↗

Multielement determination and speciation of major-to-trace elements in black tea leaves by ICP-AES and ICP-MS with the aid of size exclusion chromatography.

A multielement determination of major-to-trace elements in black tea leaves and their tea infusions was carried out by ICP-AES (inductively coupled plasma atomic emission spectrometry) and ICP-MS (inductively coupled plasma mass spectrometry). Tea infusions were prepared as usual tea beverage by brewing black tea leaves in boiling water for 5 min. About 40 elements in tea leaves and tea infusions could be determined over the wide concentration range in 8 orders of magnitude. The extraction efficiency of each element was estimated as the ratio of its concentration in tea infusions to that in tea leaves. From the experimental results for the extraction efficiencies, the elements in black tea leaves were classified into three characteristic groups: (i) highly-extractable elements (>55%): Na, K, Co, Ni, Rb, Cs and Tl, (ii) moderately-extractable elements (20-55%): Mg, Al, P, Mn and Zn, and (iii) poorly-extractable elements (<20%): Ca, Fe, Cu, Sr, Y, Zr, Mo, Sn, Ba and lanthanoid elements. Furthermore, speciation of major-to-trace elements in tea infusions was performed by using a combined system of size exclusion chromatography (SEC) and ICP-MS (or ICP-AES). As a result, many diverse elements were found to be present as complexes associated with large organic molecules in tea infusions.

Chromatography, Gel↗

Release of trace elements in wetlands: role of seasonal variability.

Dissolved concentrations were determined for Fe, Mn, Al, Cu, Zn, La, U, Th, Cd and As in a wetland and its recipient stream to reveal the effect of seasonal changes in environmental conditions on the cycling and transfer of trace elements at the transition between terrestrial and aquatic ecosystems. These preliminary results from the wetland show marked seasonal changes in dissolved concentration for all elements except Zn and Cu. Concentrations are found to be low until about mid-February and then increase abruptly. The onset of trace element release appears to coincide with a marked decline in redox potential and increase of organic carbon content. Because this decline is itself correlated with a pronounced increase in temperature and dissolved Fe. Mn and organic carbon content, we suggest that the microorganisms which use soil iron and manganese oxy-hydroxides as electron acceptors catalyzed the change in redox conditions and induced an increase of DOC. Temporal changes were also observed in the recipient stream which showed marked positive concentration peaks during stormflow events (except Zn). The seasonal processes occurring in the wetland appear to play a major role in determining the amount of trace elements which are transferred from the wetland to the river.

Copper↗

[Effect of the long-term intake of yttrium in drinking water on trace elements in F1 generation mice].

The effects of the long-term intake of yttrium on trace elements in tissues and yttrium in brain of F1 generation mice were studied so as to elucidate some physiological function of the rare earths. The mice were fed with Y3+ (0, 23.25 mg/L, 2325.00 mg/L) dissolved water at different levels for seven months. The level of trace elements such as Cu, Cd, Pb and Y in brain and Se in brain, liver, spleen and kidney of F1 generation mice were measured by ICP-MS and atom fluorescent method. The results showed that, compared with control mice, significant changes in content of Se (P < 0.05) in spleen and Y (P < 0.05) in brain were observed, but no changes were found in content of Pb, Cd, and Cu in brain for the high dose group, and an increase was detected in content of Se(P < 0.05) in spleen for the low dose group, suggesting that long-term intake of Y3+ might enhance the absorption of Se in some tissue that might be one of the biological effect of rare earth and, Y3+ might enter young mammalian brain.

Animals↗

On the toxic effects of tetraethyl lead and its derivatives on the chrysophyte Poterioochromonas malhamensis. VII. Protective action of thiol compounds, vitamins, trace elements, and other agents.

The influence of 45 different substances on the growth inhibiting effects of triethyl lead chloride (TriEL) in cultures of the unicellular alga Poterioochromonas malhamensis was studied. Ten thiol or disulfide compounds, 9 vitamins, 12 trace elements, 14 miscellaneous agents, and 9 combinations of these agents were tested. The agents were applied to the algal cultures in three different concentrations simultaneously with 10 microM TriEL and incubated for 72 hr. While none of the tested thiol and disulfide compounds remarkably protected the algae from TriEL toxicity, two vitamins (tocopheryl acetate, ascorbic acid), one trace element (zinc), adenosine-5'-triphosphate Na2 salt, cyclic AMP, and concanavalin A as well as combinations of some of these agents were found to suppress markedly the growth inhibiting effects of TriEL. Zinc was the most effective agent; it increased algal growth in TriEL-treated cultures by about 70 times as compared with cultures containing TriEL alone. A combination of 10 essential trace elements was even more protective and almost completely suppressed TriEL toxicity. In contrast to this, some of the other agents potentiated the toxic effects of TriEL (e.g., magnesium, molybdenum, caffeine, deuteriumoxide, chlorpromazine, dimethylsulfoxide) in the tested concentration ranges. The most protective agents Zn, VitC, and VitE did not prevent the inhibitory effects of TriEL on microtubule (MT) assembly in vitro, suggesting that their in vivo protection is based on mechanisms other than direct protecting MTs from the attack of the lead compound. Zn had no direct influence on the stability and half life of TriEL in the growth medium. The lack of protection found by the thiol compounds used suggests that most probably general thiol interaction of TriEL is not its major toxic mechanism of action. It is postulated that the protective action of Zn, VitE, and VitC is directly or indirectly mediated by suppression of TriEL-induced peroxidation processes in the poisoned algae. The protective agents found provide a basis for further screening experiments in order to test their "therapeutic" potency in experimental animals poisoned with organolead.

Disulfides↗

Health effects of natural dust: role of trace elements and compounds.

This article reviews the health effects of trace elements carried in natural dusts of geologic or geochemical origin. The sources of these dusts are diverse, including volcanoes, dust storms, long-range transport of desert dust, and displacement through natural processes such as landslides and earthquakes. The primary focus is dust exposures affecting communities rather than occupational groups (which have been comprehensively explored in other publications). The principal elements and compounds reviewed are trace metals (including As, Hg, Cd, and Fe), radioactive elements, fluoride, silicates, natural asbestiform compounds, and alkali salts. The pathways by which such agents affect human populations are explored, including carriage through water, air, soil, and the food chain. The mechanisms of biotoxicity and the acute and chronic consequences on health associated with these elements are described. The discussion explores problems inferring risk and disease causation from natural dust exposures using standard epidemiological indicators, particularly for chronic outcomes, and will argue for the importance of the ecological perspective in assessing pathogenesis. The authors stress the global scale of the problem, which remains underevaluated and underreported in terms of health implications.

Animals↗

[Determination of trace elements in Chinese traditional medicines by atomic absorption spectrometry].

The 9 kinds of Chinese traditional medicines which are used to cure diabetes including Xiaokewan, Yuquanwan, Kelening, Jiangtangshu, Jiangtang I-V are digested with HNO3-HClO4 (4:1) mixed acid. The 12 trace elements of copper, zinc, nickel, cobalt, manganese, chromium, molybdenum, iron, calcium, magnesium, cadmium and lead in the solution are determined by atomic absorption spectrometry. Its recovery ratio by standard addition is 97%-105%, and RSD is lower than 5%. This method has good accurate. The results obtained show that except Cd and Pb all other ten trace elements contents in the drug are high. The results of this paper provide useful data for studying the relation between the contents of these trace elements and the medical effect.

Copper↗

The relationship between trace elements and cardiac markers in acute coronary syndromes.

Previous studies have demonstrated increased serum copper and iron levels and decreased selenium and zinc levels in patients with myocardial infarction. Furthermore, the prognostic value of the levels of trace elements in myocardial infarction has been stressed. We examined serum levels of Cu, Fe, Zn and Se, as well as glutathione peroxidase (GPx), a selenoenzyme with antioxidant properties, and C-reactive protein (CRP), a marker of inflammation, in acute coronary syndromes (ACS) regarding their relationship to cardiac troponins and creatine kinase-MB mass (CK-MBm), important prognostic markers. Serum trace elements, GPx activity and CRP were determined in 70 patients with ACS who were admitted within 12 h after the onset. Differences in these parameters were evaluated in three groups of patients divided according to the levels of cardiac markers: group III consisted of patients with high increases in cTnT, cTnI and CK-MBm (> or =0.9 ng/mL, > or =1.0 ng/mL, > or =30 ng/mL, respectively), patients with milder increases in these markers were included in groups II and I consisted of patients with values just above the upper reference limits. Serum Fe levels increased significantly in group II and even more prominently in group III compared to group I (p = 0.04, 0.002, respectively). There was no significant difference between groups II and III. The increase in serum Cu was significant in group III compared to both groups II and I (p = 0.04, 0.001, respectively). There was no significant difference between groups I and II regarding Cu and Zn. The decrease in serum Se and GPx levels was significant only between groups III and I (p = 0.004 for Se and p = 0.0001 for GPx). CRP levels showed a significant increase in group III compared to groups II and I (p = 0.03 and 0.001). CRP showed a significant positive and GPx a significant negative correlation to the cardiac markers cTnT, cTnI and CK-MBm. Cu was positively correlated to all cardiac markers, while the positive correlation between Fe and cardiac markers was significant only for cTnI. Both Zn and Se were negatively correlated to cTnT, and Se was also to cTnI. In conclusion, the increase in serum levels of Cu and Fe and the decrease in serum levels of Zn and Se in patients with higher levels of troponins and CK-MBm imply that trace element levels are related to the degree of myocardial damage and thus may play a role in the pathogenesis of ischemic heart disease. The strong correlations between cardiac markers and both CRP and GPx suggest that these parameters are promising prognostic factors in acute coronary syndromes.

Adult↗

The distribution patterns of trace elements in the brain and erythrocytes in a rat experimental model of iodine deficiency.

Cretinism is a disease characterized by neurological defects associated with severe iodine deficiency. In a rat model of severe iodine deficiency, we investigated the distribution pattern of trace elements (iodine [I], selenium [Se], and bromine [Br] in brain tissue samples; potassium [K], calcium [Ca], manganese [Mn], iron [Fe], copper [Cu], zinc [Zn], rubidium [Rb], and lead [Pb] in erythrocytes) after supplementing the rats with I and/or Se. Neutron activation analysis, proton induced x-ray emission and x-ray fluorescence were used. The serum levels of total and free thyroxine (T4, FT4), and of total, free, and reverse triiodothyronine (T3, FT3, rT3, respectively) were assessed by radioimmunoassay. The results were statistically evaluated by one-way analysis of variance and bivariate correlation. The study indicated that the levels of T4, FT4, and rT3 increased in the serum of iodine-deficient rats supplemented with I or I + Se. In the same animals, we documented alterations of the content of Br in the brain, and of Zn, Mn, Cu, and Rb in erythrocytes, whereas the brain content of I and Se was unchanged. Thus, I and I + Se supplementation improves thyroid hormone metabolism but affects the content of selected trace elements in erythrocytes and of Br in the brain. The data stimulate further clarification of the role of trace elements in the central nervous system.

Animals↗