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Rare earth elements and hypertension risk among housewives: A pilot study in Shanxi Province, China
2017
Wang, Bin | Yan, Lailai | Huo, Wenhua | Lu, Qun | Cheng, Zixi | Zhang, Jingxu | Li, Zhiwen
Studies have shown that residents living near rare earth mining areas have high concentrations of rare earth elements (REEs) in their hair. However, the adverse effects of REEs on human health have rarely been the focus of epidemiological studies. The goal of this study was to evaluate the relationship between REEs in hair and the risk of hypertension in housewives. We recruited 398 housewives in Shanxi Province, China, consisting of 163 women with hypertension (cases) and 235 healthy women without hypertension (controls). We analyzed 15 REEs (lanthanum (La), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), Yttrium (Y), cerium (Ce), praseodymium (Pr), and neodymium (Nd)) and calcium (Ca) accumulated in housewives hair over a period of two years. The results revealed that, with the exception of Eu, concentrations of the REEs in hair were higher in the cases than in the controls. The univariate odds ratios (ORs) of the 14 REEs were >1, and four of the REEs (Dy, Tm, Yb, and Y) also had adjusted ORs > 1. The increasing dose-response trends of the four REEs further indicated the potential for increased hypertension risk. Moreover, the REEs were negatively correlated with Ca content in hair. These results might suggest an antagonistic effect of REEs on Ca in the human body. It was concluded that high intake of REEs might increase the risk of hypertension among housewives.
Show more [+] Less [-]Trace elements in hazardous mineral fibres
2016
Both occupational and environmental exposure to asbestos-mineral fibres can be associated with lung diseases. The pathogenic effects are related to the dimension, biopersistence and chemical composition of the fibres. In addition to the major mineral elements, mineral fibres contain trace elements and their content may play a role in fibre toxicity. To shed light on the role of trace elements in asbestos carcinogenesis, knowledge on their concentration in asbestos-mineral fibres is mandatory. It is possible that trace elements play a synergetic factor in the pathogenesis of diseases caused by the inhalation of mineral fibres. In this paper, the concentration levels of trace elements from three chrysotile samples, four amphibole asbestos samples (UICC amosite, UICC anthophyllite, UICC crocidolite and tremolite) and fibrous erionite from Jersey, Nevada (USA) were determined using inductively coupled plasma mass spectrometry (ICP-MS). For all samples, the following trace elements were measured: Li, Be, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Sb, Cs, Ba, La, Pb, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, U. Their distribution in the various mineral species is thoroughly discussed.The obtained results indicate that the amount of trace metals such as Mn, Cr, Co, Ni, Cu and Zn is higher in anthophyllite and chrysotile samples, whereas the amount of rare earth elements (REE) is higher in erionite and tremolite samples. The results of this work can be useful to the pathologists and biochemists who use asbestos minerals and fibrous erionite in-vitro studies as positive cyto- and geno-toxic standard references.
Show more [+] Less [-]Metal distribution in sediment cores from São Paulo State Coast, Brazil
2011
Silva, Paulo S.C. | Damatto, Sandra R. | Maldonado, Caio | Fávaro, Deboráh I.T. | Mazzilli, Barbara P.
Ten sediment core samples with lengths ranging from 35 to 100cm were collected in the Baixada Santista region and analyzed to determine As, Br, Co, Cr, Cs, Fe, Rb, Sb, Ta, Th, U, Zn and rare earths (Sc, Ce, Eu, La, Lu, Nd, Sm, Tb and Yb) level concentrations using instrumental neutron activation analysis (INAA). The studied region is located in the southeastern coast of São Paulo State and is comprised of a densely urbanized area, the largest industrial complex of the country, with a predominance of petrochemical and fertilizer plants. It is also home to Brazil’s most important and busiest port. The conclusions found that the As, La, Sm, Ne, Ce, Eu, Hf, Ta, Th, and U elements have a high background level in the region and that Fe and Zn were the main indicators of anthropogenic contribution in the sediments.
Show more [+] Less [-]Adsorption of 177Lu from Water by Using Synthetic Hydroxyapatite
2021
Jiménez Reyes, Melania | Almazán-Sánchez, Perla Tatiana | Jiménez-Becerril, Jaime | Solache-Ríos, Marcos
Adsorption behavior of lutetium by hydroxyapatite (HAP) was investigated by considering pH, adsorbent dose, contact time, initial concentration of lutetium, and temperature. The adsorbent was synthesized and characterized by X-ray diffraction (XRD; JCPDS file 01–04-3708), and the point of zero charge was 7.22. When the initial pH (pHᵢ) was 3, the final pH (pHf) of the system was approximately 6, and in these conditions, approximately 98% of lutetium is present as Lu³⁺. The equilibrium of the adsorption system was reached in 5 min, and the HAP retained 99.2 ± 0.3% of lutetium. The experimental kinetic and isotherm data were adjusted to the pseudo-second-order and Freundlich models, respectively, indicating a chemisorption mechanism on a heterogeneous surface. Experimental and literature data revealed that Freundlich parameters depend on the cation size of the lanthanide elements; Kf (Freundlich constant) values linearly decrease with the ionic radii of the elements. The adsorption process was exothermic and spontaneous, as indicated by the negative values of enthalpy and Gibbs free energy values. The entropy value is small and negative, which may indicate that the affinity between Lu³⁺ and HPA is not strong.
Show more [+] Less [-]Lanthanide recovery by silica-Cyanex 272 material immobilized in alginate matrix
2020
Mohammedi, Habib | Miloudi, Hafida | Boos, Anne | Bertagnolli, Caroline
Mesoporous silica impregnate with Cyanex 272 (bis/2,4,4-trimethylpentyl/phosphinic acid) extractant was immobilized into an alginate matrix to obtain a composite sorbent easy to use and applicable in fixed-bed column continuous systems. The sorption efficiency of this material was tested for the recovery of Eu(III) ions from aqueous solutions in batch and continuous mode. The competition among rare earths ions (europium, lanthanum, and lutetium) and among rare earths and calcium or sodium ions was investigated. High calcium concentrations strongly reduce the sorption capacity of the alginate matrix that composes the hybrid material and the Cyanex 272 impregnated into silica powder improves the rare earths’ sorption performance in this calcium charged media. The experimental breakthrough curves obtained were satisfactory fitted by Thomas model.
Show more [+] Less [-]Residual titanium flakes as a novel material for retention and recovery of rare earth and relatively rare earth elements
2020
Barbulescu, Laura Eugenia | Dumitriu, Cristina | Dragut, Dumitru Valentin | Nicoara, Adrian | Badanoiu, Alina | Pirvu, Cristian
The aim of this study was the valorization of titanium flakes (waste) from titanium and titanium alloy ingot production factories and using in applications related to metals recovery as retention bed for some trace metals. The titanium flakes were anodized for surface nanostructuration with TiO₂ nanotubes and then annealed in order to increase the surface stability. The nanostructured titanium flakes were loaded and pressed in a retention column linked with inductively coupled plasma spectrometer (ICP-OES). This system allowed determination of trace elements such as beryllium, lanthanum, lutetium, and ytterbium from sample solutions. Beryllium recovery percentage was over 90%, while lanthanides have just a satisfactory recovery percentage (about 65% Yb and Lu and 50% La). The TiO₂ nanotube architecture was not affected during utilization being able to perform for a long time. A thermodynamic and kinetic study was done for beryllium due to its successful adsorption recovery percentage. The obtained results showed that the titanium waste is a promising material for rare earth and relatively rare earth elements retention and recovery. Graphical abstract Graphical abstract
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