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1.
Pediatr Pulmonol ; 55(4): 1012-1019, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32068966

RESUMEN

Tobacco or tobacco products (TTP) are harmful because they contain nicotine and some heavy metals. In this study, it was aimed to evaluate whether the responses of parents to questionnaires were compatible with the hair cotinine levels of their children, and to investigate whether exposure to environmental tobacco smoke (ETS) and living conditions increased the levels of cotinine, lead (Pb), arsenic (As), and cadmium (Cd) in the hair samples of the children. Questionnaires were administered to the parents questioning household consumption of TTP and living conditions. Children were grouped as "exposed to ETS" (E-ETS) and "not exposed to ETS" (NE-ETS). This grouping was performed through a questionnaire-based evaluation, and a hair cotinine cut-off value-based evaluation. According to the questionnaire-based evaluation, there were no significant differences in hair Pb, As, and Cd levels between the groups (P-values: .337, .994, and .825, respectively). The hair cotinine of the E-ETS group was higher (0.24 ± 0.21 vs 0.22 ± 0.15 ng/mg), but the difference was not statistically significant (P = .317). According to the cotinine evaluation, cotinine, Pb, and As levels were statistically higher in the E-ETS group (P < .001, <.001, and .036, respectively), but there was no statistical difference between the groups in terms of Cd levels (P = .238). Our results showed that exposure to ETS increased the levels of cotinine, Pb, and As in the hair samples of children, and the questionnaire responses of the parents about their smoking habits might not be compatible with the hair cotinine levels of the children.


Asunto(s)
Cotinina/análisis , Cabello/química , Metales/análisis , Contaminación por Humo de Tabaco , Niño , Cotinina/metabolismo , Femenino , Cabello/metabolismo , Humanos , Masculino , Metales/metabolismo , Nicotina/análisis , Padres , Fumar , Encuestas y Cuestionarios , Nicotiana
2.
Artículo en Inglés | MEDLINE | ID: mdl-28437687

RESUMEN

Tourmaline defines a group of complex borosilicate forms as accessory mineral in igneous and metamorphic rocks and they act an important role in the interpretation of the chemical composition changes of the composition of the host fluid of the magma. The variety of tourmaline can be identified by using optical microscopy, X-Ray Diffraction (XRD) and by determining its chemical composition through Polarized Energy Dispersive X-Ray Fluorescence (PED-XRF) methods. However, microscopic investigations and XRD analyses are not quite adequate for detailed determination of tourmaline sub-groups. In addition, the use of chemical composition of tourmaline as a strict indicator of geochemical processes might be a misleading method. In this study, variable tourmaline crystals were collected from three different pegmatitic occurrences in Behrekdag, Yozgat and Karakaya granitic bodies of Central Anatolia to identify their chemical properties through Confocal Raman Spectroscopy (CRS), PED-XRF and XRD analyses. The confocal Raman spectrometry of collected tourmalines from the Behrekdag, Yozgat and Karakaya granites are in the compositions of schorl, schorl and elbaite respectively. The dominant compositional groups of these tourmalines are in the form of schorl. Raman shift values of tourmalines revealed four bands centered at almost 1050, 750, 400 and 300cm-1. The first group of the band arises from SiO stretching, the second from BO stretching and the other two belong to bending modes of OBO and BOAl with symmetrical deformation of SiOSi. The strongest spectra near 360cm-1 should belong to the bonding of AlO. As a result, the confocal Raman studies are more sensitive for identification of tourmaline subgroup compositions and have a quite important in the explaining source of the magma.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 137: 516-26, 2015 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-25240144

RESUMEN

The studied area is located in Western Anatolia and situated on the NE-SW directed Usak-Güre cross-graben that developed under a crustal extensional regime during the Late Miocene-Pliocene. Silica occurrences have been mostly found as mushroom-shaped big caps. They also show sedimentary structures such as stratification. Silica occurrences are milky white, yellowish white, yellow to chocolate brown and rarely pale blue, bluish gray in color and have no crystal forms in hand specimen. Some of the silica samples show conchoidal fracture. Silica minerals are mostly chalcedony, low-quartz (α-quartz) and sporadically opal-CT in spectras, according to confocal Raman spectrometry. The silica samples have enrichment of Fe (1000-24,600 ppm), Ca (100-10,200 ppm), P (4-3950 ppm) and Mn (8-3020 ppm). Other striking elements in fewer amounts are Ba (0.9-609.6 ppm), Ni (15.7-182.3 ppm) and Co (18.6-343.1 ppm). In chondrite-normalized spider diagram, silica samples display partial enrichment in LIL elements (Rb, Ba, Th). The δ(18)O (‰ V-SMOW) values for silica samples vary from 18.4‰ to 22.8‰ and are similar to low temperature hydrothermal silica. Confocal Raman spectrometry and oxygen isotope indicate that the silica minerals may precipitate from host fluid which is relatively has low temperatures hydrothermal solutions derived from the residual melt of basaltic magma.


Asunto(s)
Minerales/química , Dióxido de Silicio/análisis , Bario/análisis , Calcio/análisis , Sedimentos Geológicos/química , Geología/métodos , Hierro/análisis , Minerales/análisis , Isótopos de Oxígeno , Fósforo/análisis , Cuarzo , Dióxido de Silicio/química , Espectrometría por Rayos X , Espectrometría Raman , Turquía , Difracción de Rayos X
4.
Environ Monit Assess ; 185(8): 6739-50, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23315100

RESUMEN

In this study, the concentrations of 13 elements (Al, Fe, Mn, Cr, Ni, Zn, Co, As, Pb, Cu, Mo, Hg, and Cd) were determined in the sediments of three different sites in the Kapulukaya Dam Lake between May 2007 and November 2008. They ranged from 1.47 to 4.64 for Al, 0.92 to 3.48 for Fe (in percent), 326.60 to 1053.00 for Mn, 98.00 to 1,116.00 for Cr, 24.70 to 127.10 for Ni, 14.80 to 124.20 for Zn, 11.0 to 43.20 for Co, 5.00 to 29.30 for Cu, 9.10 to 69.70 for As, 8.60 to 34.00 for Pb, 2.50 to 5.20 for Mo, 1.00 to 1.60 for Hg, and 0.50 to1.80 for Cd in microgram per gram dry weight sediment. The contamination degree of the sediment was assessed on the basis of enrichment factor and corresponding sediment quality guideline. The calculated enrichment factors (EF, measured metal vs. background concentrations) indicated that the effect of man-made activities on the occurrence of concentrations could be accounted for the majority of heavy metals namely Mn, As, Ni, Cu, Zn, Cr, Co, Mo, and Cd, whereas such affect was not detected for Hg and Pb. The maximum values of the EF were represented by As, minimum values by Hg at all sites. Mean EF values were 36.60 and 0.70 for As and Hg, respectively. This study has clearly assessed a certain level of heavy metal pollution in the region, based particularly on the findings from sediment.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Lagos/química , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Turquía , Contaminación Química del Agua/estadística & datos numéricos
5.
Artículo en Inglés | MEDLINE | ID: mdl-17689287

RESUMEN

Medium to large volume ignimbrites usually show vertical changes in terms of color, mineral components, texture and geochemistry. Determination of vertical changes in single extensive ignimbrite flow unit is difficult and requires careful studies. Color changes in ignimbrite flow units are very important for earth scientists. This may cause to identify the same ignimbrite series with different definition. Incesu ignimbrite has a wide distribution in the Central Anatolian Volcanic Province (CAVP). It is classified into three levels as lower, middle and upper according to color and welding degree. There is a sharp contact between the lower and middle level. The lower level is dark brown to black in color and the middle level has pinkish red to red color. The present paper focuses on the investigation of color changes between the ignimbrite levels by using micro-XRF and confocal Raman spectrometry. Micro-XRF and Raman spectrometry studies were performed on the polished thin sections of the lower and middle levels with different compositions. These differences were because of the compositional changes of K and slightly Fe elements distribution within the matrix. The dark brown to black color of the lower level was related to the high concentration of the K and Fe relatively to the middle level. Confocal Raman spectrometry investigations exhibited the matrix of the lower level mainly composed of anorthoclase, supporting the results of the micro-XRF.


Asunto(s)
Vidrio/química , Espectrometría Raman , Color , Elementos Químicos , Geografía , Espectrometría por Rayos X
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