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Forty-six ceramic shards from the Early Bronze Age (EBA) archaeological site of Tappeh Gabri (the archaeological site 013), dated back to the latter half of the third millennium BCE and located at the Varzaneh Plain, central Iran, were studied using micro energy dispersive X-ray fluorescence (µ-EDXRF) and petrographic analysis. The precision and accuracy of quantitative data obtained by µ-EDXRF were tested using a series of geological certified reference materials (CRM). The expanded uncertainty and the Mantel test on data obtained by µ-EDXRF showed accurate and precise quantitative µ-EDXRF estimation of elements present in the CRMs above their quantification limit. We show that the majority of the ceramics at the Varzaneh Plain is most probably local product. Discussions prompted collecting further compositional data and performing petrographic investigation from the ceramic shards from southern and south-western Iran in order to shed light on the origin of the ceramic shards excavated at the Varzaneh Plain. [ABSTRACT FROM AUTHOR]

• XRF is used to characterize non-destructively 29 Sasanian drachmas (499–628 AD). • The elemental composition is determined, checking authenticity and purity. • Semi-quantitative analysis identified two potential forgeries among the 29 coins. • Five Khosrow II coins with a special inscription had Ag content over 99 %. • Au content could identify cerussite as the original ore for silver mining. X-Ray Fluorescence (XRF) analysis is widely employed in the field of cultural heritage due to its non-destructive nature. µ-EDXRF was used to study 29 Sasanian drachmas from a private collection at the Department of Humanities, University of Trieste. The coins were issued between 499 and 628 AD, during the reigns of four Sasanian kings (Kawad I, Khosrow I, Hormizd IV, and Khosrow II). This study aimed to determine the elemental composition of the alloy's surface, assess the coins' fineness, and identify potential forgeries or signs of devaluation. Eight XRF spectra were acquired for each sample, revealing a primary composition of Ag, with traces of Cu, Au, and Pb. Semi-quantitative analysis showed Ag content exceeding 95% in nearly all coins, with two suspected forgeries identified (coin no. 13 minted during the reign of Hormizd IV and coin no. 18 from the reign of Khosrow II). Five drachmas from Khosrow II's reign, marked with the inscription "afid", exhibited Ag content above 99 %, supporting the historical hypothesis of superior quality compared to other drachmas from the same period. Finally, the %Au and the presence of Pb provided further indications on the origin of Ag, allowing hypotheses on the mineral sources. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive analysis of three bronze ring fragments with distinct corrosion patterns from the Nanhai No.1 shipwreck, employing optical microscopy, SEM–EDS, µ-RS, and µ-EDXRF techniques. The results exhibit that each bronze ring fragment displays unique corrosion characteristics but shares similarities in their patina structures: an outer layer composed of CuFeS2) and malachite, a subsurface layer of CuS) and/or Copper Tin Sulfide, and an inner copper-depleted layer rich in tin and lead. These layers indicate the artifacts experienced three distinct corrosion stages corresponding to aerobic, anaerobic, and re-aerobic conditions, aligned with the ship's sinking, sediment coverage, and post-recovery scenarios. The study reveals that the pre-anaerobic corrosion products significantly influenced the corrosion kinetics in subsequent environments, affecting the final composition and structure of the patina. Notably, the outer CuS layer, regardless of its compactness, is unable to prevent the selective dissolution of copper from the alloy. The formation of a cuprite layer beneath the copper-depleted layer post-recovery suggests a corrosion resumption due to changes in environmental oxygen levels. These insights emphasize the need for targeted conservation strategies for marine-recovered bronze artifacts, considering their complex corrosion history and environmental interactions. [ABSTRACT FROM AUTHOR]

A fragment of the NWA 2975 Martian meteorite, an enriched basaltic shergottite, was analysed to complete its geochemical characterisation performed 10 years ago. By this means, the feasibility of the employed techniques in a combined way for present and future space exploration missions can be tested. For this aim, Raman spectroscopy was used supported by micro energy dispersive X‐ray fluorescence (μ‐EDXRF) and laser‐induced breakdown spectroscopy (LIBS) for an accurate interpretation of molecular and elemental results. Raman spectroscopy results from two setups, InVia from Renishaw and RLS Simulator, were compared. The major minerals detected by Raman spectroscopy were pyroxenes (mainly augite, pigeonite and enstatite) and plagioclases (mainly shocked maskelynite). Raman spectroscopy allowed defining different metal compositions for these main minerals based on the secondary Raman spectroscopy bands in the 200–500 cm−1 region. In addition, other minerals were found such as merrillite, as well as pyrrhotite and apatite, in several veins and cracks of the meteorite, in agreement with the initial report by the Meteoritical Bulletin. Moreover, it should be highlighted that coesite was found for the very first time in this meteorite. [ABSTRACT FROM AUTHOR]

In this work, some micro-samples belonging to the open-air rock art site of Cueva de la Vieja (Alpera, Albacete, Spain) were analysed. These samples were collected after and before a desalination treatment was carried out, with the aim of removing a whitish layer of concretion that affected the painted panel. The diagnostic study was performed to study the conservation state of the panel, and to then confirm the effectiveness of the treatment. Micro energy dispersive X-ray fluorescence spectrometry, Raman spectroscopy, and X-ray diffraction were employed for the characterization of the degradation product as well as that of the mineral substrate and pigments. The micro-samples analysis demonstrated that the painted layer was settled on a dolomitic limestone with silicon aggregates and aluminosilicates as well as iron oxides. The whitish crust was composed by sulfate compounds such as gypsum (CaSO4·2H2O) with a minor amount of epsomite (MgSO4·7H2O). An extensive phenomenon of biological activity has been demonstrated since then in almost all of the samples that have been analysed, and the presence of calcium oxalates monohydrate (CaC2O4·H2O) and dehydrate (CaC2O4·2H2O) were found. The presence of both calcium oxalates probably favoured the conservation of the pictographs. In addition, some carotenoids pigments, scytonemin (C36H20N2O4), and astaxanthin (C40H52O4) were characterized both by Raman spectroscopy and by X-ray diffraction. Hematite was found as a pigment voluntarily used for the painting of the panels used in a mixture with hydroxyapatite and amorphous carbon. The results of the analyses of the samples taken after the cleaning treatment confirmed a substantial decrease in sulphate formation on the panel surface. [ABSTRACT FROM AUTHOR]

The Chalcolithic period in the Lisbon region, Portugal, is usually divided into three phases chronologically: the Early Chalcolithic, characterized by cylindrical corrugated cups, Full Chalcolithic by so-called acacia-leaf decoration, and Late Chalcolithic by Bell Beaker pottery. The aim of this research is to determine if Chalcolithic ceramic raw materials and production techniques have remained the same over time and whether the pottery is locally produced. Regarding the Lisbon region, 149 ceramic samples from four Chalcolithic settlements (Vila Nova de São Pedro, Penedo do Lexim, Espargueira and Baútas) were evaluated concerning textural, chemical and mineralogical compositions. Textural analysis was performed using optical microscopy, chemical characterization was achieved using micro-energy dispersive X-ray fluorescence spectrometry and mineralogical characterization was undertaken using X-ray powder diffraction and petrographic microscopy as main techniques. Results suggest that production techniques may have remained similar throughout all the Chalcolithic period, with firing temperatures between 700 and 800 °C. Multivariate analysis of results from chemical and mineralogical analyses suggests that multiple sources of raw materials must have been used in the manufacture of the pottery collected at the four Chalcolithic settlements.

In this study, 160 silver-copper alloy denarii and antoniniani from the 3rd century A.D. were studied to obtain their overall chemical composition. The approach used for their characterisation is based on a combination of physical, chemical, and chemometric techniques. The aim is to identify and quantify major and trace elements in Roman silver-copper coins in order to assess changes in composition and to confirm the devaluation of the currency. After a first cataloguing step, μ-EDXRF and SEM-EDX techniques were performed to identify the elements on the coins' surface. A micro-destructive sampling method was employed on a representative sample of the coins to quantify the elements present in the bulk. The powder obtained from drilling 12 coins (keeping the two categories of coins separate) was dissolved in an acidic medium; heated and sonicated to facilitate dissolution; and then analysed by ICP-AES and ICP-MS. The two currencies had different average alloy percentages; in particular, the % difference of Ag was about 8%. The other elements were found in concentrations <1 wt%. Of these, the element highest in concentration were Pb and Sn, which is in agreement with the literature. The multivariate analysis performed on the data acquired revealed two groups of coins, corresponding to the two currencies. [ABSTRACT FROM AUTHOR]

The Chalcolithic period in the Lisbon region, Portugal, is usually divided into three phases chronologically: the Early Chalcolithic, characterized by cylindrical corrugated cups, Full Chalcolithic by so-called acacia-leaf decoration, and Late Chalcolithic by Bell Beaker pottery. The aim of this research is to determine if Chalcolithic ceramic raw materials and production techniques have remained the same over time and whether the pottery is locally produced. Regarding the Lisbon region, 149 ceramic samples from four Chalcolithic settlements (Vila Nova de São Pedro, Penedo do Lexim, Espargueira and Baútas) were evaluated concerning textural, chemical and mineralogical compositions. Textural analysis was performed using optical microscopy, chemical characterization was achieved using micro-energy dispersive X-ray fluorescence spectrometry and mineralogical characterization was undertaken using X-ray powder diffraction and petrographic microscopy as main techniques. Results suggest that production techniques may have remained similar throughout all the Chalcolithic period, with firing temperatures between 700 and 800 °C. Multivariate analysis of results from chemical and mineralogical analyses suggests that multiple sources of raw materials must have been used in the manufacture of the pottery collected at the four Chalcolithic settlements. [ABSTRACT FROM AUTHOR]

In this work, micro-Raman spectroscopy and micro-energy-dispersive X-ray fluorescence spectroscopy (µ-EDXRF) were applied on microsamples taken from the Plaiko Zubixe footbridge (1927) located in Ondarroa (Basque Country, Spain) in order to investigate the original paint coating and make an evaluation of the conservation state before its restoration. Elemental and molecular images were acquired for the study of the compounds distribution. Some modern pigments such as phthalocyanine blue and green pigments, minium, calcium carbonate, Prussian blue, and hematite were identified. Barium sulfate and titanium dioxide were recognized as opacifier agents. Thanks to the study of the stratigraphies, it has been possible to determine the original paint layer, which includes lead white, ultramarine blue, carbon black, and barium sulfate. In addition, colorimetric analyses made it possible to know the CIELab values of the original layer in order to reproduce the original colour during the planned restoration work. The massive presence of chlorine detected by µ-EDXRF and the corrosion products of the rust layer, in particular akaganeite and hematite, highlighted the atmospheric impact in the conservation of the bridge because they were due to the effect of both marine aerosol and to the presence of acidic components in the environment coming from anthropogenic activity. This work demonstrated the usefulness of a scientific approach for the study of industrial archaeology heritage with the aim to contribute to its conservation and restoration. [ABSTRACT FROM AUTHOR]

This work describes the characterization of green pigments in wall paintings from the Andean churches of San José de Soracachi and Santiago de Callapa in Bolivia, located on an ancient colonial commercial route known as the Silver Route. To approach our goal, microsamples extracted from the mural paintings and mineral samples, from a mine of the same area, were studied by using micro‐Raman spectroscopy complemented with micro‐energy‐dispersive X‐ray fluorescence spectroscopy (μ‐EDXRF) and scanning electron microscopy with energy‐dispersive X‐ray spectroscopy (SEM‐EDS) analysis. The use of gypsum as the preparation layer was detected, and it suggests a secco painting technique. Antlerite, a basic copper sulfate, was identified suggesting a preference for its use as green pigment in the mural paintings of Andean churches that may be related to the local availability of this mineral. Indeed, this study revealed the presence of heterogeneous particles of the basic copper sulfate together with aluminosilicates, quartz and iron oxides among others, which points to a mineral origin of the green pigment because the same compounds were found in the samples taken in the mine. Because a phase transition has been noticed during the Raman analyses, due to a high power of the laser radiation, some tests have been carried out, varying the laser power, and coupling the Raman spectrometer to a temperature‐controlled stage to verify under which conditions the degradation of the mineral sample of antlerite occurs allowing in this way a correct characterization of basic copper sulfate pigments. These results contribute to the study of the Andean colonial artistic cultural heritage, and this information will be made available for the construction of a database of local pigments of mineral origin used in Andean colonial art. [ABSTRACT FROM AUTHOR]

Petrography and mineralogy are fundamental for understanding processes in various geoscientific fields. Plutonic rock nomenclature is based on mineralogical composition. Therefore, identifying and quantifying minerals is a key for plutonic rock classification. To accomplish this, novel advancements in instrumentations, such as energy dispersive x-ray fluorescence mapping (μ-EDXRF) or hyperspectral imaging (HSI) provide fast and non-destructively spatially resolved and large-scale chemical information. This work describes a comprehensive approach to combine chemical, mineralogical and textural information from μ-EDXRF, Laser Induced Breakdown Spectroscopy (LIBS) and HSI for petrographic analysis of plutonic rocks. Using supervised classification of spectral information, mineral distribution maps are obtained for image analysis including geometrical data of each grain, such as grain size, grain orientation and grain location for subsequent targeted analysis and the modal mineralogy for plutonic rock classification in a QAPF-diagram for 20 rock slabs. The combination of the three mapping techniques can provide valuable information within the limit of each technique such as of spatial resolution or element sensitivity, but with little time needed for sample preparation and measurement. In general, it is an objective, repeatable and quantifiable way for modal mineralogy and petrographic image analysis. [ABSTRACT FROM AUTHOR]

Thirty-three Byzantine copper-based coins (so-called anonymous follis) from 970 to 1085 CE were investigated in order to determine the elemental composition both of the bulk and of the surface. The ancient coins analysed - belonging to the Thomas Bertelè Collection, now located in the Bottacin Museum of Padova (Italy) - were studied by way of physical, chemical and chemometric testing techniques. This study aims to obtain information on socio-economic aspects of the Byzantine Empire using chemical and physical data of currency as indirect indicators. First, the weight, diameter and thickness of each piece were measured, then a micro-Energy Dispersive X-ray Fluorescence (μ-EDXRF) technique was applied on a cleaned and polished area of the surface of the coin to evaluate the presence of minor elements in a non-destructive fashion. A micro-destructive sampling method for both surface and bulk samples, based on mechanically drilling the edge, was finally employed, and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) was used for the quantitative determination of Cu (the major alloying element), Pb, As, Fe, Zn, Ag, Ni, Sn and Mn (minor elements) in the powder which resulted from drilling each coin, previously dissolved via aqua regia dissolution technique overnight at room temperature. The average copper concentration of the folles was 95.9 ± 3.1% for the bulk and 91.7 ± 3.5% for the surface. The Pb-Cu ratio appears to be an index which can be used to discriminate between different coins, in particular for Class B (from 1030 to 1042 CE), as confirmed by exploratory chemometric data analysis. According to our results, all the anonymous Byzantine folles under examination were minted in much the same way and using the same mineral raw materials. Using the chemical data measured on the bulk, we can grasp that the monetary choice of the period under study excluded silver, gold and bronze (concentrations of Pb is low, while Sn resulted undetectable or unquantifiable) to turn, substantially, to a copper-only coinage (deducted the impurities given by the gangue of the starting minerals). Moreover, along the observed period of 120 years, the mass of the coins was significantly reduced (with an overall loss of material of approximately 60%). • Useful procedure to determine the composition of the folles using a micro-destructive sampling method and ICP-AES. • Significant presence of Cu in the Byzantine Empire indicating follis as a fiduciary coin • New data for a numismatic database regarding anonymous folles from the 11th century in the Eastern Roman Empire area. [ABSTRACT FROM AUTHOR]

Abstract: Medicaments essential for alleviation of diseases may sometime adversely affect dental health by eroding the enamel, owing to their acidic nature. It is therefore highly desirable to be able to detect these effects quickly and reliably. In this study, we evaluated the erosive capacity of four most commonly prescribed respiratory disease syrup medicaments on enamel using micro‐energy‐dispersive X‐ray fluorescence spectrometry (µ‐EDXRF) and attenuated total reflection Fourier transform infrared spectroscopy (ATR‐FTIR). Fifty‐five enamel fragments obtained from 30 bovine teeth were treated with artificial saliva (S), acebrofilin hydrochloride (AC), ambroxol hydrochloride (AM), bromhexine hydrochloride (BR), and salbutamol sulfate (SS); by immersing in 3 mL of respective solutions for 1 min, three times a day at intervals of 1 hr, for 5 days. µ‐EDXRF analysis of enamel surface did not reveal significant erosion caused by the medications. However, ATR‐FTIR showed a detectable shift in the phosphate (PO4) antisymmetric stretching mode (ν3) at ∼985 cm−1 for AM, BR, and SS, indicating erosion. Multivariate statistical analysis showed that AC, AM, SS, and BR could be classified with 70%, 80%, 100%, and 100% efficiency from S (control), further highlighting the ability of ATR‐FTIR to identify degree of erosion. This suggests ATR‐FTIR may be used to rapidly and nondestructively investigate erosive effects of medicaments. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the erosive potential of four most commonly prescribed syrup medicaments for respiratory diseases. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy combined with multivariate statistical analysis and micro-energy-dispersive X-ray fluorescence spectrometry (μ-EDXRF) mapping was performed. Fifty-five root dentin fragments obtained from the buccal surface of 30 bovine teeth were prepared and divided into five experimental groups (n = 10): control-artificial saliva (S), acebrofilin hydrochloride (AC), ambroxol hydrochloride (AM), bromhexine hydrochloride (BR), and salbutamol sulfate (SS). The S group was stored only in artificial saliva and the other groups were treated with the medicaments (immersed for 1 min in 3 mL of the medication, three times daily, with 1-h intervals between the immersion cycles, during 5 days, 15 immersion cycles). There were a significant decrease in the Ca and P weight percentages (wt%) for dentin after medication treatments, except for AC (p > 0.05). Mineral content of dentin showed a clear gradation with increasing Ca and P wt% reduction in the order S < AC < AM < BR < SS. SS resulted in a significant increase in Ca/P ratio when compared to the control (p < 0.001). ATR-FTIR combined with multivariate, statistical analysis can quickly and reliably indicate extent of dentin erosion. Considering syrups with high-erosive potential should always follow with proper oral hygiene practices or search for an alternative medications void of such detrimental effects. Regular and prolonged use of these medicaments might bear the risk of causing erosion. [ABSTRACT FROM AUTHOR]

The metal accumulation in edible parts of the plants is an important issue to provide a healthy food for the population. Some plants have the ability to take up certain trace elements from metal-polluted soils. Depending on the characteristics of the area and the environment where these plants have been grown, a different metal distribution can be observed on them. The aims of this work were to determine which are the general trends of metals distribution (e.g. K, Ca, Mn, Fe, Zn, Cu, Sr, etc.) in the different parts (roots, stems, leaves and fruits) of Solanum lycopersicum plants located in a seaside village (Barrika, Basque Country, North of Spain) and to asses if there is any potential dangerous accumulation in the edible part, the tomato fruit. Moreover, it was also evaluated if halogen elements (e.g. Cl, Br) emitted by the marine aerosol to the atmosphere are also highly distributed on these parts of Solanum lycopersicum plants. To perform this study a portable micro energy dispersive X-ray fluorescence spectrometer (μ-EDXRF) was used, which allows performing a mapping of each section of the plant in order to obtain the distribution of each element. The results obtained showed that a portable μ-EDXRF is a good analytical technique in order to know the distributions of these elements. Most of the elements identified in the roots, stem and leaves were not detectable in the fruit using this elemental technique. Moreover, it was detected the possible influence of the marine aerosol taking in to account the high distribution in all the parts of the plants of Cl and Br, except in the fruits. [ABSTRACT FROM AUTHOR]

Energy dispersive X-ray fluorescence mapping (μ-EDXRF) is a fast and non-destructive method for chemical quantification and therefore used in many scientific fields. The combination of spatial and chemical information is highly valuable for understanding geological processes. Problems occur with crystalline samples due to diffraction, which appears according to Bragg's law, depending on the energy of the X-ray beam, the incident angle and the crystal parameters. In the spectra these peaks can overlap with element peaks suggesting higher element concentrations. The aim of this study is to investigate the effect of diffraction, the possibility of diffraction removal and potential geoscientific applications for X-ray mapping. In this work the μ-EDXRF M4 Tornado from Bruker was operated with a Rh-tube and polychromatic beam with two SDD detectors mounted each at ± 90° to the tube. Due to the polychromatic beam the Bragg condition fits for several mineral lattice planes. Since diffraction depends on the angle, it is shown that a novel correction approach can be applied by measuring from two different angles and calculating the minimum spectrum of both detectors gaining a better limit of quantification for this method. Furthermore, it is possible to use the diffraction information for separation of differently oriented crystallites within a monomineralic aggregate and obtain parameters like particle size distribution for the sample, as it is done by thin section image analysis in cross-polarized light. Only with μ-EDXRF this can be made on larger samples without preparation of thin sections. [ABSTRACT FROM AUTHOR]

This study assesses whether the concentrations of biologically important elements in bones are altered by long-term consumption of cadmium (Cd)-contaminated water. Heavy metal poisoning has significant impact on humans, and pollutants such as Cd are often found at high concentrations in waterways. Twelve Sprague Dawley rats consumed water with 50 p.p.m. Cd (Cd group), and another 12 consumed normal water (control group). Six subjects from each group were sacrificed after 2 weeks and the others after 4 weeks. Spectra were acquired from the femur by using the EDAX Eagle III micro-XRF setup, and quantitative calculations were performed by using the fundamental parameter method to determine the concentrations of elements. A bone calcium/phosphorus concentration ratio (Ca/P) of 2.07 ± 0.001 is observed in the spectra from control subjects after 2 weeks and 2.07 ± 0.001 after 4 weeks. In Cd subjects, Ca/P after 2 weeks is 2.04 ± 0.001 and after 4 weeks is 1.97 ± 0.003. Statistically significant differences are obtained when comparing controls with Cd subjects at both time points and when comparing Cd subjects at both time points. Cadmium poisoning significantly affects bone Ca and P concentrations, increasing the likelihood of osteoporosis and other bone diseases. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Over the years, the presence of mercury in amalgam fillings has raised some safety concerns. Amalgam is one of the most commonly used tooth fillings and contains approximately 50% of elemental mercury and 50% of other metals, mostly silver, tin and copper. Amalgam can release small amounts of mercury vapor over time, and patients can absorb these vapors by inhaling or ingesting them. In this study, 10 human teeth treated with dental amalgam were analyzed using energy dispersive X-ray fluorescence (EDXRF) to study the diffusion of its constituents, Ag, Cu, Sn and Hg. The used EDXRF setup, makes use of a polycapillary lens to focus radiation up to 25 μm allowing the mapping of the elemental distribution in the samples. Quantification was performed using the inbuilt software based on the Fundamental Parameters method for bulk samples, considering a hydroxyapatite matrix. The teeth were longitudinally cut and each slice was scanned from the surface enamel to the inner region (dentin and pulp cavity). Mercury concentration profiles show strong levels of this element close to the amalgam region, decreasing significantly in the dentin, and increasing again up to 40,000 μg·g − 1 in the cavity were the pulp used to exist when the tooth was vital. [ABSTRACT FROM AUTHOR]

The purpose of this in vitro study was to assess whether the mineralization degree and elemental content in tooth enamel are altered when bleaching the teeth with two different over-the-counter bleaching gels, exceeding the recommendations of the manufacturer. In order to perform this evaluation, 12 healthy teeth were used, six samples were treated with Teeth Whitening Home Kit, and the other six samples were treated with WHITE! (Bingo-UK) bought in online shopping sites, for the period of 39 days. The pH of each product and the elemental content of each sample, before and after, were obtained by energy dispersive X-ray spectrometry and phosphate (PO43-) profile was evaluated with Raman spectroscopy. Data was analyzed accordingly to a pre-established plan with a mixed-model ANOVA for repeated measures, significance was set at 5%. Both products were markedly acidic and below enamel critical level of 5.5. Moreover, seven days after treatment, demineralization was significant, wherein at the end of the study the degree of demineralization seems to be permanent. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The purpose of this in vitro study is to assess whether the elemental content of tooth enamel is altered when bleaching the teeth with bleaching gel. Because of tooth bleaching growing popularity and to match the public demands, manufacturers increased the range of bleaching products available, changing its presentation, techniques and concentration of active principles. This way, two different bleaching products were compared, one for in-office and another for domestic use. In order to perform this evaluation, sound vestibular surfaces of anterior healthy teeth, extracted for periodontal or orthodontic reasons, were treated with the bleaching products accordingly to manufacturer instructions. Spectra were acquired using the M4 Tornado μ-XRF setup, and quantitative calculations were performed using fundamental parameter method to determine the elemental composition of the analyzed samples before and after treatment. No significant statistical differences in the mineral content of the analyzed teeth were obtained. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A set of bronzes recovered from Fraga dos Corvos (Macedo de Cavaleiros) archaeological site, located in Northern Portugal, was analyzed to investigate their lead isotope ratios. The studied metallic artefacts have diverse typologies and include two bar fragments, four fibulae, a pendant and fragments of a possible cauldron. Besides these, two metallurgical remains (nodule and droplet) were also analyzed. Elemental analysis by μ-EDXRF showed that bronzes have a Sn content varying between 5.1 and 13.9% and a Pb content from 1.4 to 6.1%, which allowed to select a suitable methodology for lead separation, prior to isotope ratio determinations. In these alloys the Pb isotope determinations (204Pb, 206Pb, 207Pb and 208Pb) are influenced by matrix effects that decrease the sensitivity and the reproducibility of the measurements. Analytical procedure consisted in electrochemical Pb separation by anodic oxidation. The determination of Pb isotope ratios was made by ICP-MS with a quadrupole mass filter and provided the first results of Pb isotopic composition of bronze alloys from the Northern Portuguese territory. Isotope ratios determinations were obtained with a relative standard deviation below 0.5%. Pb isotope ratio distributions allowed the identification of different composition patterns indicating probable distinct provenances, although the similar isotopic ratios among some artefacts and the metallurgical remains pointed out to local metallurgical activities. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a globally ubiquitous pollutant and one of the most dangerous metal contaminants, which presents a high risk of bioaccumulation in living organisms. In this study, we mapped the distribution of Hg and other trace elements in zebrafish (Danio rerio), which were exposed to mercury (II) chloride in order to assess its toxicity, bioaccumulation and distribution in fish organs. Adult zebrafish were exposed for 7 days to different concentrations of mercury (II) chloride and the elemental distribution was obtained through the micro-energy dispersive X-ray fluorescence technique (μ-EDXRF). The results showed that Hg levels, measured in fish tissues, were indicative of bioaccumulation within some of its organs (e.g. visceral mass, gills), and that the physiological processes of accumulation were highly dose-dependent. In addition, the results showed higher concentrations of Hg in the gills. Moreover, other trace elements (e.g. Fe, Cu and Zn) levels were not altered after fish exposure to mercury(II) chloride. The μ-EDXRF results were assessed along with the determination of some oxidative stress biomarkers (e.g. antioxidant enzymes) to understand the effects behind the Hg bioaccumulation and toxicity. These results suggest that the metabolic changes in zebrafish due to the exposure to Hg are consistent with oxidative stress. [ABSTRACT FROM AUTHOR]