The Experts below are selected from a list of 1386 Experts worldwide ranked by ideXlab platform
A G Coedo - One of the best experts on this subject based on the ideXlab platform.
-
X-ray fluorescence determination of major and minor elements in ferrotitanium, ferroniobium and ferrovanadium from compressed pellets and fusion beads
X-Ray Spectrometry, 2002Co-Authors: A G Coedo, Teresa Dorado, Isabel Padilla, Francisco José AlguacilAbstract:This paper describes the x-ray fluorescence determination of major and minor elements in ferrotitanium, ferroniobium and ferrovanadium. Samples preparation was accomplished using two different procedures: compressed pellets and fusion beads. Calibration graphs were prepared by mixing two Ferroalloys of each of the considered types in different proportions. These Ferroalloys were selected from industrial batches, providing the most varied composition available in order to cover as completely as possible the ranges of composition listed in ISO specifications. Total reproducibility tests, incorporating sample preparation and measurement, were performed using six samples prepared with the Ferroalloys having the highest alloying grade. The relative standard deviation (RSD) values referred to the major element in Fe–Ti, Fe–Nb and Fe–V were 0.20, 0.17 and 0.21%, respectively, when using compressed pellets, and 0.16, 0.14 and 0.13% when using fusion beads. As regards the minor elements, the RSD values were in all cases below 5% for compressed pellets and below 3% for fused beads. The criterion applied to test the agreement of the two methods showed that the difference between the results provided by both samples preparation systems may be explained in terms of random errors. Accuracy was checked by analysing Certified Reference Materials of each of the types of Ferroalloys studied. Copyright © 2002 John Wiley & Sons, Ltd.
-
spark ablation inductively coupled plasma mass spectrometry applied to the semi quantitative panoramic analysis of Ferroalloys
Applied Spectroscopy, 2000Co-Authors: A G Coedo, Teresa Dorado, Isabel Padilla, B J FernandezAbstract:The coupling of inductively coupled plasma mass spectrometry (ICP-MS) with spark ablation (SA) was applied for the semi-quantitative determination of impurities in different types of Ferroalloys. The sparking operating conditions were optimized, and a restrictive path including a cyclone and a spray chamber was used to decrease the quantity of sparked material reaching the plasma, to prevent torch injector and sampling cone blockage. Samples were mixed in a 1:2 sample-to-graphite ratio and pressed into pellets for direct solid sampling by the spark. The advantage of the technique includes the benefit of easily determining some refractory elements that are very difficult to dissolve. The method was tested on three different types of Ferroalloys: Fe-Ti, Fe-Nb, and Fe-V. A single standard Ferroalloy sample was used as an external calibration sample to create a complete response curve for each type of Ferroalloy base. Industrial Ferroalloys, chemically characterized by using different analytical methods, were applied as calibration samples. The use of a calibration sample closely matching the Ferroalloy material to be analyzed was found to be essential if accurate analyses were to be obtained. Certified Reference Materials of the three Ferroalloys types tested-BAS (Bureau of Analyzed Samples) 579-1 (Fe-Nb alloy); BAM (Bundesanstalt fur Materialprufung) 589-1 (Fe-Ti alloy); and BAS 577-1 (Fe-V alloy)-were analyzed to evaluate the accuracy attainable in this panoramic mode. Most of the results, ranging from 0.05% to 5% m/m, were observed to be accurate to within 6-18.6% of the certified value, and the precision was better than 17.8% relative standard deviation. Determination limits based on 10 times the standard deviation of six replicates of a blank graphite pellet were on the μg g-1 level.
-
x ray fluorescence analysis of Ferroalloys development of methods for the preparation of test and calibration samples
Analyst, 1994Co-Authors: A G Coedo, M T Dorado, Carlos J Rivero, Isabel G CoboAbstract:Methods were developed with a view to evaluating various sample preparation systems for use with X-ray fluorescence techniques in order to determine the major and minor components of Ferroalloys, which are used as alloy-forming elements in steel making. The methods were compared in terms of simplicity and rapidity and these parameters were assessed in relation to the accuracy and precision of the results. The samples were prepared in three formats: metal samples, by dilution with iron and remelting in an induction furnace; pellets, by direct compaction of the ground material, and beads, by alkaline melting of the pre-oxidized sample. The tests used to optimize these methods were conducted with commercial Ferroalloys, previously characterized by employing wet chemical and spectroscopic methods. Reproducibility and precision studies were conducted on samples obtained using each of the three sample preparation systems. The precisions (relative standard deviations) of major element determinations were <0.8, <1.0 and <0.5% and those for minor elements were <5, <5 and <3% for metal samples, pellets and beads, respectively. The accuracy of the methods was checked by analysing reference materials of each type of Ferroalloy.
Donald R Smith - One of the best experts on this subject based on the ideXlab platform.
-
assessing the contributions of metals in environmental media to exposure biomarkers in a region of Ferroalloy industry
Journal of Exposure Science and Environmental Epidemiology, 2019Co-Authors: Lindsey J Butler, Marco Peli, Laura Borgese, Chris Gennings, D Placidi, Neil J Zimmerman, Hsiaohsien L Hsu, Brent A Coull, Robert O Wright, Donald R SmithAbstract:Residential proximity to Ferroalloy production has been associated with increased manganese exposure, which can adversely affect health, particularly among children. Little is known, however, about which environmental samples contribute most to internal levels of manganese and other Ferroalloy metals. We aimed to characterize sources of exposure to metals and evaluate the ability of internal biomarkers to reflect exposures from environmental media. In 717 Italian adolescents residing near ferromanganese industry, we examined associations between manganese, lead, chromium, and copper in environmental samples (airborne particles, surface soil, indoor/outdoor house dust) and biological samples (blood, hair, nails, saliva, urine). In multivariable regression analyses adjusted for child age and sex, a 10% increase in soil Mn was associated with increases of 3.0% (95% CI: 1.1%, 4.9%) in nail Mn and 1.6% (95% CI: −0.2%, 3.4%) in saliva Mn. Weighted-quantile-sum (WQS) regression estimated that higher soil and outdoor dust Mn accounted for most of the effect on nail Mn (WQS weights: 0.61 and 0.22, respectively, out of a total of 1.0). Higher air and soil Mn accounted for most of the effect on saliva Mn (WQS weights: 0.65 and 0.29, respectively). These findings can help inform biomarker selection in future epidemiologic studies and guide intervention strategies in exposed populations.
-
metal fractionation in soils and assessment of environmental contamination in vallecamonica italy
Environmental Science and Pollution Research, 2013Co-Authors: Laura Borgese, Filippo Donna, Roberto Lucchini, Stefania Federici, Annalisa Zacco, Alessandra Gianoncelli, L Rizzo, Donald R Smith, Laura E Depero, Elza BontempiAbstract:Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy), where Ferroalloy industries were active for a century until 2001. The extent in which emissions from Ferroalloy plants affected metal concentration in soils is not known in this area. In this study, the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal component analysis (PCA) was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed distinguishing of different loadings and mobility of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure.
Laura Borgese - One of the best experts on this subject based on the ideXlab platform.
-
assessing the contributions of metals in environmental media to exposure biomarkers in a region of Ferroalloy industry
Journal of Exposure Science and Environmental Epidemiology, 2019Co-Authors: Lindsey J Butler, Marco Peli, Laura Borgese, Chris Gennings, D Placidi, Neil J Zimmerman, Hsiaohsien L Hsu, Brent A Coull, Robert O Wright, Donald R SmithAbstract:Residential proximity to Ferroalloy production has been associated with increased manganese exposure, which can adversely affect health, particularly among children. Little is known, however, about which environmental samples contribute most to internal levels of manganese and other Ferroalloy metals. We aimed to characterize sources of exposure to metals and evaluate the ability of internal biomarkers to reflect exposures from environmental media. In 717 Italian adolescents residing near ferromanganese industry, we examined associations between manganese, lead, chromium, and copper in environmental samples (airborne particles, surface soil, indoor/outdoor house dust) and biological samples (blood, hair, nails, saliva, urine). In multivariable regression analyses adjusted for child age and sex, a 10% increase in soil Mn was associated with increases of 3.0% (95% CI: 1.1%, 4.9%) in nail Mn and 1.6% (95% CI: −0.2%, 3.4%) in saliva Mn. Weighted-quantile-sum (WQS) regression estimated that higher soil and outdoor dust Mn accounted for most of the effect on nail Mn (WQS weights: 0.61 and 0.22, respectively, out of a total of 1.0). Higher air and soil Mn accounted for most of the effect on saliva Mn (WQS weights: 0.65 and 0.29, respectively). These findings can help inform biomarker selection in future epidemiologic studies and guide intervention strategies in exposed populations.
-
metal fractionation in soils and assessment of environmental contamination in vallecamonica italy
Environmental Science and Pollution Research, 2013Co-Authors: Laura Borgese, Filippo Donna, Roberto Lucchini, Stefania Federici, Annalisa Zacco, Alessandra Gianoncelli, L Rizzo, Donald R Smith, Laura E Depero, Elza BontempiAbstract:Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy), where Ferroalloy industries were active for a century until 2001. The extent in which emissions from Ferroalloy plants affected metal concentration in soils is not known in this area. In this study, the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal component analysis (PCA) was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed distinguishing of different loadings and mobility of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure.
Roberto Lucchini - One of the best experts on this subject based on the ideXlab platform.
-
High Prevalence of Parkinsonian Disorders Associated to Manganese Exposure in the
2016Co-Authors: Roberto Lucchini, Stefano Borghesi, Giovanni ParrinelloAbstract:High prevalence of Parkinsonian disorders associated to manganese exposure in the vicinities of Ferroalloy industries. Am J Ind Me
-
neurofunctional dopaminergic impairment in elderly after lifetime exposure to manganese
Neurotoxicology, 2014Co-Authors: Silvia Zoni, Chiara Benedetti, Chiara Fedrighi, Marco Peli, Filippo Donna, Stefano Guazzetti, Roberto Lucchini, Elza BontempiAbstract:Background Manganese (Mn) is an essential element that can become neurotoxic through various exposure windows over the lifespan. While there is clear evidence of Mn neurotoxicity in pediatric and adult occupational populations, little is known about effects in the elderly who may exhibit enhanced susceptibilities due to compromised physiology compared to younger adults. In the province of Brescia, Italy, the Valcamonica area has been the site of three Ferroalloy plants operating from 1902 to 2001. Metal emissions of Mn and to a lesser extent lead (Pb) have impacted the surrounding environment, where a high prevalence of Parkinsonism was previously observed. This study aimed to assess neurocognitive and motor functions in healthy elderly subjects residing for most of their lifetime in Valcamonica or in a reference area unimpacted by Ferroalloy plant activity.
-
metal fractionation in soils and assessment of environmental contamination in vallecamonica italy
Environmental Science and Pollution Research, 2013Co-Authors: Laura Borgese, Filippo Donna, Roberto Lucchini, Stefania Federici, Annalisa Zacco, Alessandra Gianoncelli, L Rizzo, Donald R Smith, Laura E Depero, Elza BontempiAbstract:Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy), where Ferroalloy industries were active for a century until 2001. The extent in which emissions from Ferroalloy plants affected metal concentration in soils is not known in this area. In this study, the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal component analysis (PCA) was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed distinguishing of different loadings and mobility of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure.
Elza Bontempi - One of the best experts on this subject based on the ideXlab platform.
-
neurofunctional dopaminergic impairment in elderly after lifetime exposure to manganese
Neurotoxicology, 2014Co-Authors: Silvia Zoni, Chiara Benedetti, Chiara Fedrighi, Marco Peli, Filippo Donna, Stefano Guazzetti, Roberto Lucchini, Elza BontempiAbstract:Background Manganese (Mn) is an essential element that can become neurotoxic through various exposure windows over the lifespan. While there is clear evidence of Mn neurotoxicity in pediatric and adult occupational populations, little is known about effects in the elderly who may exhibit enhanced susceptibilities due to compromised physiology compared to younger adults. In the province of Brescia, Italy, the Valcamonica area has been the site of three Ferroalloy plants operating from 1902 to 2001. Metal emissions of Mn and to a lesser extent lead (Pb) have impacted the surrounding environment, where a high prevalence of Parkinsonism was previously observed. This study aimed to assess neurocognitive and motor functions in healthy elderly subjects residing for most of their lifetime in Valcamonica or in a reference area unimpacted by Ferroalloy plant activity.
-
metal fractionation in soils and assessment of environmental contamination in vallecamonica italy
Environmental Science and Pollution Research, 2013Co-Authors: Laura Borgese, Filippo Donna, Roberto Lucchini, Stefania Federici, Annalisa Zacco, Alessandra Gianoncelli, L Rizzo, Donald R Smith, Laura E Depero, Elza BontempiAbstract:Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy), where Ferroalloy industries were active for a century until 2001. The extent in which emissions from Ferroalloy plants affected metal concentration in soils is not known in this area. In this study, the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal component analysis (PCA) was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed distinguishing of different loadings and mobility of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure.