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Neurobiol. Aging 2005 26 439 447 Gilbert, M. E., Lasley, S. M. (2007) Developmental lead (Pb

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The heavy metal (cadmium, Cd; chromium, Cr; copper, Cu; nickel, Ni; lead, Pb and zinc, Zn), sodium (Na) and sulphur (S) contamination of roadside topsoils and the accumulation of these elements in chicory (Cichorium intybus L.) as indicator plant was studied at different sites in Nyíregyháza (Hungary) between 1994 and 1996. In roadside urban topsoils (collected from a depth of 0–10 cm at a distance of 0.1 or 0.2–4.0 m from..

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Concentration of carbon (C), oxygen (O), nitrogen (N), magnesium (Mg), aluminium (Al), silicon (Si), phosphorus (P), mercury (Hg), sulphur (S), lead (Pb), chlorine (Cl), potassium (K), cadmium (Cd), calcium (Ca), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu) and zinc (Zn), in the form of weight percentage, in the needles of different age classes, current and previous year one, of two sites, Risnjak National Park and Donja Dobra (control), were measured by X-ray microanalysis (EDAX) in the Scanning Electron Microscope in silver fir trees (Abies alba Mill.). The analysis suggests that accumulation of elements, in both years, particularly that of heavy metals, appeared in polluted site, like Risnjak, in the higher amount, whereas in non polluted, like Donja Dobra, in the lower amount. Moreover, it seems likely that elements at the first sites were accumulated and contaminated in very young current year needles, while in non polluted in somewhat older, the previous year ones.

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Energy dispersive X-ray fluorescence (EDXRF) analysis of aerosol samples in Nairobi is presented. Results show that elemental concentrations are of the order of 10–4 to 10–6 g/m3 for most elements analyzed. The total suspended particulate (TSP) matter was between 30–80 g/m3 for the entire sampling period between December 1993 to October 1994. Levels of lead (Pb) are below WHO guidelines. However, the obtained bromine (Br) to Pb ratio: 0.3–0.51, shows the origin of Pb to be from vehicular emissions. This ratio was particularly high during the months of April to July 1994 which were also found to be very active in terms of weather parameters.

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Activated carbons (AC) have been long recognized as prominent absorbents in industries and feature numerous applications in preventing or absorbing the harmful gases and liquids and could be employed for filtration and remediation or even reutilization of chemicals. In order to investigate the capacity of AC in reducing the absorption of heavy metals (HM) including lead (Pb) and cadmium (Cd) and dual complex (Pb × Cd) by spinach, a factorial experiment in a completely randomized design with three replications on a pot trial was conducted. Three factors including five levels of AC 0, 5000, 10000, 15000, 20000 mg/kg soil, one concentration level of Pb 4,000 mg/kg soil and one concentration level of cadmium Cd 8 mg/kg soil were tested. The index of heavy metal concentration was calculated in leaf, stem and root and their corresponding dry weights. Results illustrated that in contaminated soils, plants with AC exhibited a superior reduction of absorption of HM vis-à-vis the plants without AC. The foremost result regarding the impact of AC on reducing the concentration of Pb and Cd was observed in 20,000 level of AC. This reveals that AC declined the soil contamination and lessened the accumulation of HM into the shoots and roots. Results suggest that the application of AC may be an eligible solution for decreasing the translocation of HM into the plants.

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Chronic lead (Pb) intoxication has been linked to Alzheimer's disease (AD). Lead, like many heavy elements, tends to accumulate in bone. PIXE is a powerful analytical tool which permits the determination of Pb at the g/g level without requiring sample digestion. GFAAS is one of the most sensitive methods for the determination of Pb and is capable of determining ng/g levels in solution. For bone analyses by GFAAS, sample dissolution and a matrix modifier are required. Rib bone samples were analyzed for Pb by PIXE and GFAAS. IAEA Animal Bone (H-5) was used as a secondary standard for Pb with both methods to ensure accuracy. The range of Pb concentrations in human rib bone was 1.4–11.5 g/g for the trabecular surface by PIXE, 1.3–45 g/g for the cortical surface by PIXE, and 1.54–11.75 g/g for whole bone by GFAAS. No significant difference (p>0.05) was found for AD versus control for either surface or for whole bone.

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Potato and beetroot were grown on soils previously treated with heavy metal salts. Each particular microelement had a high concentration in both potato and beetroot [cadmium (Cd) 3.7 and 55.4, lead (Pb) 8.1 and 3.0, and mercury (Hg) 5.8 and 6.8 mg/kg dry matter, respectively]. In a metabolic balance trial 16 New Zealand White rabbits were fed 50 grams of basal diet and potato or beetroot ad libitum. The apparent digestibility of major nutrients and the accumulation of the microelements in different organs were investigated. Both potato and beetroot samples of high Pb and Hg content had the significantly (p < 0.05) lowest digestibility of organic matter and nitrogen-free extract. The Cd ingested from both potato and beetroot accumulated in the kidneys and liver (2.85 and 1.48 as well as 0.459 and 0.265 mg/kg, respectively). All the microelements (Cd, Pb and Hg) accumulated in the testicles (0.196, 0.32 and 0.199 mg/kg, respectively), reducing the rate of spermatogenesis. The tissue retention ofheavy metals depends not only on the element itself, but also upon the ‘carrier’ feedstuff.

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A new heterobimetallic nitrilotriacetatoperoxotitanate complex of titanium and lead [Pb(H2O)3]2[Ti2(O2)2O(nta)2]·4H2O (C6H6O6N=H3nta) was isolated in pure crystals directly from the solution containing tetrabutyl orthotitanate, hydrogen peroxoide, lead acetate, and nitrilotriacetic acid at pH = 2.0–4.0. The isolated complex was characterized by elemental analyses, IR spectrum, thermal analysis (TG), and single-crystal X-ray diffraction. The single-crystal X-ray structural analysis revealed that the titanium atom is N,O,O′,O′′-chelated by the nitrilotriacetate and O,O′-chelated by the peroxo group and was coordinated to the bridging O atom in an overall pentagonal-bipyramidal geometry. The thermal decomposition of this precursor led to the formation of phase-pure lead titanate (PbTiO3) at ≥450 °C. The morphology, microstructure, and crystalline of the resulting PbTiO3 product have been characterized by BET, transmission electron microscopy, and powder X-ray diffraction. The TEM micrographs revealed that the size of the as-synthesized crystallines to be 50–100 nm range. The BET measurement revealed that the PbTiO3 powders had a surface area of 5.6 m2/g.

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Alteration of the antioxidant system may be related to lead (Pb) hepatotoxicity. This study was carried out to investigate the possible beneficial effect of thymoquinone (TQ), the major active ingredient of volatile oil of Nigella sativa seeds, against Pb-induced liver antioxidant defense system impairment. Adult male rats were randomized into four groups: control group received no treatment, Pb group was exposed to 2000 ppm of Pb acetate in drinking water, Pb-TQ group was cotreated with Pb plus TQ (5 mg/kg/day, per os) and TQ group receiving only TQ. All treatments were applied for five weeks. TQ alone did not induce any significant changes in the enzymatic and non-enzymatic antioxidant status. By contrast, Pb exposure significantly decreased not only reduced glutathione level, but also superoxide dismutase, glutathione peroxidase, catalase and glutathione reductase activities in the liver tissue. Interestingly, when coadministrated with Pb, TQ significantly improved the affected antioxidant parameters. In conclusion, our results indicate a protective effect of TQ against Pb-induced liver antioxidant capacity impairment and suggest that this component might be a clinically promising alternative in Pb hepatotoxicity.

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