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Abstract Twenty-six samples of mortar used for various construction applications (joint mortars, floor mortars, filling mortars and plasters) were collected from different areas of the archaeological site of Pompeii (Campania - Sothern Italy). The mortar samples belong to various historical periods covering approximately 2000 years, from the 2nd century BC to the post excavation period (18–19th century). The samples were characterized employing Optical Microscopy (OM), X-ray Powder Diffraction (XRPD), X-ray Fluorescence (XRF), Electron Probe Micro Analysis (EPMA) and Raman Spectroscopy. Moreover, image analysis was carried out using JMicroVision software in order to determine the percentages of binder, macropores and aggregate, in terms of crushed ceramic fragments (cocciopesto), rock fragments and monocrystals. The application of these techniques allowed obtaining a complete chemical and minero-petrographic characterization of the samples, which may prove useful for preparing compatible repair mortars for future restoration works. The archaeometric study provided new data on the production technology of the mortars and the analogies and differences observed among the samples, enabled us to distinguish different constructive phases, thus confirming or rebutting the archaeological hypothesis on the dating of some samples. By combining compositional variables through the discriminant analysis, it was also possible to analyse the time evolution of the materials and to construct preliminary multivariate statistical models, helpful to identify the various typologies of mortars used in the different historical periods. Highlights • Mortar samples from Pompeii, with different constructive functions, were studied. • Characterization of the materials can be used for preparing compatible mortars. • Analogies and differences were highlighted to identify the constructive phases. • Preliminary statistic models were proposed to discriminate materials and constructive phases. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Over the last decades, many studies have been conducted on rocks containing Naturally Occurring Asbestos (NOA) to determine the potential health risks to exposed neighboring populations. It is difficult to accurately characterize the asbestos fibres contained within the rocks as conventional techniques are not effective and have drawbacks associated with the disturbance of the sample under study. X-ray synchrotron microtomography (SR-μCT) supplemented with polarized light microscope (PLM), scanning electron microscopy analysis combined with energy dispersive spectrometry (SEM/EDS), electron probe micro-analysis (EPMA) were used for identifying asbestos fibres in a mineral matrix. As a case study, we analyzed a representative set of veins and fibrous chrysotile that fills the veins, taken from massive serpentinite outcrops (Southern-Italy). We were able to identify respirable chrysotile fibres (regulated asbestos) within the serpentinite matrix. SR-μCT of NOA veins achieved the resolution and reconstructed 3D structures of infill chrysotile asbestos fibres and other phase structures that were not resolvable with PLM, SEM or EPMA. Moreover, due to differences in chemical composition between veins and matrix, the data obtained enabled us to evaluate the vein shapes present in the massive serpentinite matrix. In particular, iron and aluminum distribution variations between veins and matrix induce different radiation absorption patterns thus permitting a detailed image-based 3D geometric reconstruction. The advantages of the SR-μCT technique as well as limitation of conventional methods are also discussed. These analytical approaches will be used for conducting future research on NOA of other minerals, which exhibit asbestiform and non-asbestiform habits within veins, including asbestos amphiboles. Unlabelled Image • Chrysotile asbestos was examined using SR-μCT for the first time. • 3D analysis provides information on the aspect ratio of chrysotile asbestos. • 3D analysis provides morphological information of the serpentinite veins. • Chemical variations were observed between the veins and the serpentinite matrix. [ABSTRACT FROM AUTHOR]

Road pavement is principally made of mineral aggregates and a bitumen binder. Aggregates, due to their mineralogical nature, have complex chemical compositions and physical properties, which are strongly dependent on the minerals that constitute the stones. In pavement technology, bitumen/aggregate affinity is of paramount importance. Moisture damage in hot mix asphalt (HMA) is one of the major concerns in durability of flexible pavements, to improve the adhesion between the bitumen and the stones and increase the life of the road pavements often it is necessary using additives as the antistripping agents. Currently, there are several techniques such as the Boiling Test, the Rolling Bottle Test (RBT), etc., which evaluate the adhesion between the bitumen and the stones, however, most of them are based on a subjective evaluation. In the present paper, several types of mineral aggregates are characterized in detail by optical microscopy (OM) and X-ray powder diffraction (XRPD) in order to correlate the Boiling Test and the contact angle method to investigate the level of bitumen/aggregate affinity. For this reason, a single type of modified bitumen and two adhesion promoters were studied. The obtained results show the reliability of the technique used. However, there are still some limitations regarding the use of a contact angle test in assessing bitumen/aggregate affinity. [ABSTRACT FROM AUTHOR]

This work focuses on comparing the inorganic content of tap and bottled mineral waters in the Calabria region (Southern Italy) performed by using robust Compositional Data Analysis (CoDA) methods and related new developments associated with a classical graphical-numerical approach. Thirty-one samples of tap waters scattered throughout the Calabrian territory and twenty-one bottled natural mineral waters of various Calabrian brands were analyzed for major and trace inorganic components. In addition, a very sensitive method based on cold vapour atomic fluorescence spectrometry (CV-AFS) has been employed to determine total mercury (Hg T) concentrations. Compositional data analysis was used to identify the main interrelationships among physico-chemical parameters, highlighting the differences between the tap waters and the bottled mineral waters. Some elements, such as Al, Mn, Fe, Zn, and Pb resulted particularly enriched in the tap waters. This group of enriched elements was probably controlled by corrosion processes from metal pipes, asking for more monitoring on the state of the public distribution water network. Li, Ca, Cr, Ni, and Cd, on the other hand, appear to be mostly contributed by natural sources affecting the overall variability of the bottled mineral waters. In this context, Cr, Cu, Hg, and Pb are mainly enriched in the sparkling bottled mineral waters. Innovative compositional indices did not highlight great differences from the Maximum Allowed Concentrations (MAC) in the two types of water, so that for the health of the consumer it is indifferent to drink tap or bottled mineral water. The results represent a fundamental base to develop monitoring plans in time to check for the maintenance of quality standards. • Tap waters and bottled mineral waters of various Calabrian brands were analyzed. • Cluster analysis evidenced variables related to natural and anthropic processes. • Hg has shown concentrations of different orders of magnitude lower than the remaining constituents. • Compositional analysis testified a good quality of the resource. [ABSTRACT FROM AUTHOR]

• Bricks from Hagia Sophia (Istanbul, Turkey) were analyzed by OM, XRF, XRPD, TGA and SEM-EDS. • An innovative micro-EDS approach on the matrix of the bricks showed that different clays were used in different building phases. • The compositional analogy between the bricks from Hagia Sophia (Istanbul, Turkey) of the 6th and 14th centuries has been highlighted. The work shows the results of a multi-analytical study performed on twenty-nine brick samples taken from Hagia Sophia in Istanbul (Turkey). Hagia Sophia, one of the most important historical buildings in the world, has a very complex construction history. This complexity is also reflected in the materials that were used for its construction. The main purpose of this work is to verify whether there are any compositional differences in the bricks used in different historical periods, but also to understand the reasons for any compositional differences between one period and another. The samples were studied by optical microscopy (OM), X-ray fluorescence (XRF), X-ray powder diffraction (XRPD) and thermogravimetric analysis (TGA), coupled with a new approach, based on the micro-chemical EDS analysis used to obtain information on the clay fraction of the matrix. The study showed that, most probably, the differences between the bricks belonging to the different construction phases are due to the composition of the clays used for their preparation. [ABSTRACT FROM AUTHOR]

This work aims to define the geothermal conceptual model of the Spezzano Albanese thermal system located in the northern sector of the Calabria Region, along the western edge of the Sibari Plain. The study confirms that the deep thermal reservoir of Spezzano Albanese is mainly hosted within the permeable levels of the evaporite deposits of the Messinian succession including siltstones with manganese mineralisation, halite, and gypsum-arenites. The thermal waters show discharging temperature between 20.2 and 26.6 °C and a high compositional variability, from Na–Cl to Na–Ca–HCO 3. The compositional evolution (from Na–Cl to Na–HCO 3) is accompanied by a decrease in both salinity and the concentrations of most dissolved constituents, including Cl, Br, B, Li, Na, K, Mg, Ca, and Ba. These variations are due to mixing between the thermal endmember, rich in Cl and related components, and low-salinity, cold shallow waters (temperature between 17.5 and 22.7 °C). The study points out that the thermal endmember derives by halite dissolution and more complex water-rock interaction processes involving (1) the dissolution of other solid phases of the Messinian deposits, as also confirmed by δ34S values of dissolved sulphate and sulphide, and (2) the precipitation of secondary solid phases (e.g., barite). The geothermometric modelling suggests that the thermal groundwaters in the deep reservoir are probably in equilibrium with either (i) quartz, calcite, disordered dolomite, low-albite, and K-feldspar, as well as with pyrophyllite and poorly crystalline kaolinite (as proxies of clay minerals) at temperatures of 65.5 ± 4.5 °C or (ii) quartz, calcite, disordered dolomite, low-albite, disordered adularia, laumontite and saponites at temperatures of 56.1 ± 4.3 °C, based on the first and second geothermometric model, respectively. The δ18O and δ2H values of water confirm a meteoric origin for the thermal waters with average recharge altitudes between 745 and 857 m a.s.l. These elevations are compatible with the recharge from the western side of the Esaro valley where evaporite successions are found close to the surface. The isotopic value of the dissolved CO 2 associated to the Spezzano Terme water highlights its likely microbial origin, as recognised for other thermal circuits hosted in sedimentary rocks of the southern Apennines. Furthermore, the thermal endmember shows a noteworthy enrichment in CH 4 with respect to air due to the interaction of groundwater with sediments rich in organic matter. Although methane could have a biogenic origin, the presence of a minor component of thermogenic methane in the gas phase dissolved in the Spezzano Terme waters cannot be completely excluded. The data obtained in this study allow to assume that the recharge meteoric waters descend to a maximum depth of about 1.1–1.4 km below the main emergence area and then the regional NE-SW fault systems probably act as a preferential pathway for the ascent of the thermal waters towards the surface. These waters discharge at Spezzano Albanese, where the crystalline-metamorphic units cropping out immediately upstream of the emergence area act as cap-rock favouring the final ascent towards the surface of the thermal waters. [Display omitted] • The geothermal conceptual model of the Spezzano Albanese thermal system has been defined. • A main deep thermal reservoir is hosted within the Messinian succession. • Geothermometric approaches provide average reservoir temperature of 65 °C. • Water stable isotopes confirm a meteoric origin with recharge altitudes of 800 m a.s.l. • Main reservoir depth of about 1.3–1.6 km below the main emergence. [ABSTRACT FROM AUTHOR]

The study, which represents an innovative scientific strategy to approach the study of natural radioactivity in terms of spatial and temporal variability, was aimed to characterize the background levels of natural radionuclides in soil and rock in the urban and peri-urban soil of a southern Italy area; to quantify their variations due to radionuclide bearing minerals and soil properties, taking into account nature and extent of seasonality influence. Its main novelty is taking into account the effect of climate in controlling natural gamma radioactivity as well as analysing soil radioactivity in terms of soil properties and pedogenetic processes. In different bedrocks and soils, activities of natural radionuclides ( 238 U, 232 Th 4 K) and total radioactivity were measured at 181 locations by means of scintillation γ-ray spectrometry. In addition, selected rocks samples were collected and analysed, using a Scanning Electron Microscope (SEM) equipped with an Energy Dispersive Spectrometer (EDS) and an X-Ray Powder Diffraction (XRPD), to assess the main sources of radionuclides. The natural-gamma background is intimately related to differing petrologic features of crystalline source rocks and to peculiar pedogenetic features and processes. The radioactivity survey was conducted during two different seasons with marked changes in the main climatic characteristics, namely dry summer and moist winter, to evaluate possible effects of seasonal climatic variations and soil properties on radioactivity measurements. Seasonal variations of radionuclides activities show their peak values in summer. The activities of 238 U, 232 Th and 4 K exhibit a positive correlation with the air temperature and are negatively correlated with precipitations. [ABSTRACT FROM AUTHOR]

This work shows the results of the spectroscopic, microchemical and petrographic study carried out on six plasters coming from three important residential buildings of the 18th century, located in Lamezia Terme (Catanzaro, Southern Italy). To study the provenance of the raw materials used to make the plasters, one sample of limestone and two samples of sand were also collected from the quarries near Lamezia Terme and compared with the historical plasters. Samples were studied by polarized optical microscopy (OM), X-ray powder diffraction (XRPD), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. The results of these analyses allowed to determine the mineralogical, petrographical and chemical characteristics of the plasters, identify the pigments used for their coloration and provide useful information about the building techniques, the raw materials employed and the production technology of plasters during the 18th century in Lamezia Terme. SEM–EDS microanalysis also revealed the presence of gold and silver on the surface of two samples. [ABSTRACT FROM AUTHOR]

Highlights: [•] First reaction path modeling exercise including the thermodynamic data for several vermiculite compositions. [•] Prevalence of dolomite dissolution leads to Mg–Al- and Ca–Al-vermiculites. [•] Prevalence of biotite dissolution leads to Mg–Mg–Fe- and Ca–Mg–Fe vermiculites. [•] Reaction path modeling confirms that vermiculite composition is also a function of pH. [Copyright &y& Elsevier]

Abstract: Mineral fibers are potential carcinogens to humans. In order to help clarify the etiology of the pathological effects of asbestos, cellular reactions to natural and synthetic asbestos fibers were compared using a lung alveolar cancer cell line (A549 epithelial cells), considered the first target of inhaled micro-environmental contaminants. Natural asbestos tremolite (NAT) fibers were collected from rocks in NW Italy. Synthetic asbestos tremolite (SAT) was iron-free and therefore considered as standard tremolite. Both fibers, subjected to mineralogical characterization by X-ray powder diffractometry, electron microscopy and energy dispersive spectrometry, fell within the definition of respirable and potentially carcinogenic fibers. Several signs of functional and structural cell damage were found after treatment with both fibers, documented by viability, motility, and morphological perturbations. Phalloidin labeling showed irregular distribution of cytoskeletal F-actin, whereas immunohistochemical investigations showed abnormal expression of VEGF, Cdc42, β-catenin, assessed as risks indicators for cancer development. Both fibers caused significant loss of viability, even compared to UICC crocidolite, but, while SAT fibers exerted a more direct cytotoxic effect, survival of damaged cells expressing high VEGF levels was detected after NAT contact. This in vitro pilot study outlines potential health risks of NAT fibers in vivo related to their iron content, which could trigger signaling networks connected with cell proliferation and neoplastic transformation. [Copyright &y& Elsevier]

Abstract: The progressive dissolution of metabasalts and serpentinites hosting the shallow aquifer of Mt. Reventino was simulated by means of the EQ3/6 software package, version 8.0, adopting both the Ideal Solid Solution Approach (ISSA) and the Double Solid Reactant Method (DSRM), which provided comparable results. A detailed field and laboratory study was performed on rock samples and local groundwaters to constrain and validate reaction path modelling. The prevalence of Ca–HCO3 over Mg–HCO3 compositions suggests that groundwaters interact chiefly with metabasalts and secondarily with the less abundant and less permeable serpentinites. The most important and active Cr source is a tremolite-rich amphibole, whose role as supplier of dissolved Cr has rarely been recognized in previous studies carried out in areas where ophiolitic rocks crop out. Speciation calculations indicate that hexavalent dissolved Cr is mainly present as chromate ion, followed by the neutral complexes (14–32mol%) and (2–12mol%), which are more mobile and more bio-available than charged solutes. All dissolved trace elements are supplied to shallow groundwaters by gradual dissolution of local rocks and, therefore, contributions linked to anthropogenic sources can be ruled out. In particular: (i) Ni is chiefly contributed to the aqueous phase by the tremolite-rich amphibole; (ii) different amounts of Sr, Ba, and Pb are provided by calcite dissolution (with Sr≫Ba>Pb), whereas the solid solution of orthorhombic carbonates acts as sink for these trace elements (with X strontianite ≫ X witherite > X cerussite); (iii) the principal source of Cu and Zn is again calcite, whereas the solid solution of trigonal carbonates represents their major sink. [Copyright &y& Elsevier]