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Asbestos, also known by its commercial name "amianthus", has been widely used in various industries due to its unique properties. However, the extensive use of asbestos has had serious consequences for human health, most notably asbestosis, an irreversible chronic lung disease. Asbestosis increases the risk of lung cancer and malignant mesothelioma, both of which are fatal. Applied sciences such as microscopy (optical and scanning electron microscopy) and geochemistry have been fundamental in characterizing the mineral fibers of asbestos to understand its role in human health. We previously used these techniques to characterize these fibers; in this study, we explored the issues associated with asbestos and asbestosis, as well as the challenges facing science communication strategies in effectively informing society and workers about these risks. The lack of scientific culture, in general, has led to a lack of public awareness of the risks of asbestos. As such, effective communication and outreach plans and strategies, including the visualization of the fibers to demonstrate why problems arise if inhaled, must be implemented to address these challenges. Educational campaigns, guidelines, and plans that are informative and actionable, teaching workers, communities, and the public about the risks of asbestos are crucial. A general knowledge of mineralogy and geochemistry is needed, and providing and disseminating proper scientific communication may help to close the knowledge gap. We use examples and experience from Spain and Italy to illustrate this matter, as we have been working on the characterization of ultramafic complexes in these countries for more than ten years. Additionally, because these countries have strict laws for asbestos-containing materials, they are currently involved in retiring and demolishing buildings and infrastructure that contain asbestos. [ABSTRACT FROM AUTHOR]

This paper presents the results of the mineralogical, petrographic and chemical study of different archaeological samples related to terracruda sculptures and other elements that were part of the architectural decoration of the Buddhist sites of Tepe Narenj and Qol‐e‐tut (Kabul, Afghanistan; fifth to 11th centuries CE). The main objective of the study was to characterize the samples using an archaeometric approach. The study helped to better understand the materials involved in the modeling of Afghan sculptures and their processing, such as the different nature of the clay layers and the finishing 'stucco' coating. The results further indicate that similarities exist among the manufacturing process of the studied samples and that used today by an ancient caste of clay artists in West Bengal (India), suggesting the existence of a continuous technological tradition that deserves to be further explored in the future. [ABSTRACT FROM AUTHOR]

Cabo Ortegal, in Spain, was declared a UNESCO Global Geopark in 2023. An ultramafic complex makes it a geologically exciting unit, where many research works have been carried out. Serpentinites, formed by the weathering of peridotites, dunites, and other ultramafic rocks, have been described in detail in previous works. Their role as a construction material has been elucidated, although due to their complexity and heterogeneity, the results of using these materials for construction are not always successful. Talcose rocks, related to serpentinites, can also be found in the complex, although it is difficult to distinguish them. Talcose rocks may be a resource to be explored and exploited in an unpopulated area. The use of talc in pharmaceuticals, cosmetics, and handicrafts makes it a material of growing importance. However, the asbestos and heavy metal content should be severely limited to prevent health issues. The goal of this work is to start the characterization of these talcose rocks before promoting their potential use in different contexts to support the economy of an underpopulated area of Spain. [ABSTRACT FROM AUTHOR]

This study focuses on the dissolution process and surface characterization of amosite fibres following interaction with a mimicked Gamble's solution at a pH of 4.5 and T = 37 °C, up to 720 h. To achieve this, a multi-analytical approach was adopted, and the results were compared to those previously obtained on a sample of asbestos tremolite and UICC crocidolite, which were investigated under the same experimental conditions. Combining surface chemical data obtained by XPS with cation release quantified by ICP-OES, an incongruent behaviour of the fibre dissolution was highlighted for amosite fibres, similarly to asbestos tremolite and UICC crocidolite. In particular, a preferential release of Mg and Ca from the amphibole structure was observed, in agreement with their Madelung site energies. Notably, no Fe release from amosite fibres was detected in our experimental conditions (pH of 4.5 and atmospheric pO2), despite the occurrence of Fe(II) at the M(4) site of the amphibole structure, where cations are expected to be rapidly leached out during mineral dissolution. Moreover, the oxidation of both the Fe centres initially present on the fibre surface and those promoted from the bulk, because of the erosion of the outmost layers, was observed. Since biodurability (i.e., the resistance to dissolution) is one of the most important toxicity parameters, the knowledge of the surface alteration of asbestos possibly occurring in vivo may help to understand the mechanisms at the basis of its long-term toxicity. [ABSTRACT FROM AUTHOR]

It is generally accepted by the scientific community that various factors such as morphometry, biodurability and chemistry contribute to the toxic potential of elongated mineral particles. As far as the chemical composition is concerned, in addition to its major structural elements, asbestos Elongated Mineral Particles (EMPs) may contain various Potentially Toxic Elements (PTEs), which could play an important role in pathological effects on human health. In this study, the concentration levels of PTEs in two actinolite elongated mineral particles and two host-serpentinite rocks, were determined by means of inductively coupled plasma spectroscopy with optical emission spectrometry (ICP-OES). The present work aims to provide a contribution to the already existent literature studies focusing on asbestos-related toxicity with new chemical data of actinolite EMPs and host-serpentinite rocks accommodating PTEs. Study samples come from the Southern Apennine thrust belt in Basilicata region (Southern Italy), where asbestos-bearing outcrops are documented in the literature and induced pathogenic effects have been reported so far. Geochemical results of actinolite samples revealed high concentrations of toxic elements especially Cr and Ni with values ranging between 158-870 ppm and 20-103 ppm respectively. Similarly, analyzed bulk serpentinite rocks showed Cr and Ni critical concentrations. Based on the obtained results it is possible to assert that populations living in areas with amphibole asbestos occurrences within serpentinite outcrops, such as the studied cases, are potentially exposed to health risks related to the presence of significant amounts of PTEs. [ABSTRACT FROM AUTHOR]

Asbestos fibers act as complex crystal-chemical reservoirs susceptible of releasing potentially toxic elements (such as ions impurities) into the lung cellular environment during permanency and dissolution. To comprehend the exact pathological mechanisms that are triggered upon inhalation of asbestos fibers, in vitro studies on possible interactions between the mineral and the biological system have been carried out mostly by using natural asbestos. However, this latter comprises intrinsic impurities such as Fe2+/Fe3+ and Ni2+ ions, and other eventual traces of metallic pathogens. Furthermore, often, natural asbestos is characterized by the co-presence of several mineral phases, fiber dimensions of which are randomly distributed in width and in length. For these reasons, it is albeit challenging to precisely identify toxicity factors and to define the accurate role of each factor in the overall pathogenesis of asbestos. In this regard, the availability of synthetic asbestos fibers with accurate chemical composition and specific dimensions for in vitro screening tests would represent the perfect tool to correlate asbestos toxicity to its chemico-physical features. Herein, to palliate such drawbacks of natural asbestos, well-defined Ni-doped tremolite fibers were chemically synthesized in order to offer biologists adequate samples for testing the specific role of Ni2+ in asbestos toxicity. The experimental conditions (temperature, pressure, reaction time and water amount) were optimized to produce batches of asbestos fibers of the tremolite phase, with uniformly distributed shape and dimensions and a controlled content of Ni2+ metal ions. [ABSTRACT FROM AUTHOR]

This study undertook the mineralogical and chemical analysis of anglesite (PbSO4), cerussite (PbCO3), gypsum (CaSO4∙2H2O), langite (Cu4(SO4)(OH)6∙2H2O), malachite (Cu2CO3(OH)2), and posnjakite (Cu4(SO4)(OH)6·H2O) detected for the first time in the abandoned Mastricarro Barite Mine (Catanzaro, Calabria, southern Italy). Geological conditions make this one of the few well-preserved, partly accessible mines in the Calabria region. Numerous mineralogical species, some beautifully crystallized, have been discovered among the alteration products of the sulfides present within the barite veins. The newly identified crystals occur as secondary minerals in the oxidized portions of deposits originally containing lead and copper sulfides; they are widely distributed and are almost always detected as microcrystals. The anglesite, cerussite, gypsum, langite, malachite, and posnjakite crystals were identified and characterized using optical microscopy (OM), micro-Raman spectroscopy (µR), and scanning electron microscopy, combined with energy dispersive spectrometry (SEM/EDS). The new mineral occurrences can be useful for scientific and didactic purposes; further, for langite, malachite, and posnjakite crystals, new Raman bands, which have not been mentioned before in the literature, were identified. [ABSTRACT FROM AUTHOR]

Health risks are often overlooked when the consequences are not evident in the short term. In restoration work, some activities can generate particles that may affect the health of workers through inhalation (e.g., cleaning of buildings or heritage artifacts composed of stone). Workers at quarries are also exposed to such materials and, therefore, the results of our work can help to increase the risk perception in workers from the stone sector, but also in construction workers in an environment associated with dust. To demonstrate the importance of protection to prevent health hazards, we laser-ablated some samples of serpentinite that contain serpentine minerals as major phase minerals. The powder obtained in filters coupled to the ablation laser was analysed, using tools such as an optical microscope, X-ray powder diffraction, a transmission electron microscope and thermal analysis. The results were very didactic, and the intention is to use them, by way of graphics and diagrams, to build information security sheets that will alert workers to the need of using masks when working, or to use tools with coupled filters such as the one used for our study. The main goal is to demonstrate that the interdisciplinary combination of scientific approaches can be used for the sake of human health. [ABSTRACT FROM AUTHOR]

Actinolite is one of the six minerals belonging to the group of asbestos minerals. There is increasing concern regarding the potential health risks from exposure to naturally occurring asbestos and asbestos-containing materials. The correct distinction of the fibrous asbestos minerals is very important not only from a scientific point of view, but also from a legislative perspective. Asbestos actinolite is currently the only asbestos mineral that has not been fully characterized from the thermal point of view. In order to compensate for this gap in scientific literature, this paper discusses the thermal behaviour of actinolite asbestos using thermogravimetric and differential scanning calorimetry. X-ray powder diffraction, Scanning and Transmission Electron Microscopy combined with energy-dispersive spectrometry were used for the characterization of actinolite fibres before and after heating at 1000 and 1200 °C in order to determine their resistance to high-temperature changes and the products of thermal recrystallization. Actinolite asbestos breaks down at approximately 1030 °C. The thermal decomposition process of actinolite asbestos consists of two distinct events followed by recrystallization into new stable crystalline phases which preserved the original fibrous morphology (known as pseudomorphosis). The thermal analysis may prove to be useful for actinolite identification and discrimination, particularly in the case of natural massive samples where asbestos tremolite–actinolite amphiboles are mutually intermixed. Furthermore, profound knowledge of the thermal behaviour of this asbestos mineral may provide us with the relevant data for understanding the crystal–chemical transformations of asbestos through thermal inertization treatment. [ABSTRACT FROM AUTHOR]

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]

Fibrous erionite is classified by the International Agency for Research on Cancer (IARC) as carcinogenic substance to humans (Group 1). In the areas where it is present in the bedrock, it may cause environmental exposure, and both professional and environmental exposures are possible when the bedrock is used for industrial applications (e.g., building materials). For health and environment protection, prevention is a priority action. In this framework, the recent guidelines of the Consensus Report of the Weinman International Conference on Mesothelioma suggest identifying locations where potentially hazardous mineral fibers (like erionite) are found in the environment, to prevent environmental exposure. The present study will show that one such potentially hazardous mineral fiber might be fibrous ferrierite. Here, the mineralogy, chemical-physical properties, and surface activity of a hydrothermal fibrous ferrierite from Monte Lake British Columbia (Canada) and a diagenetic fibrous ferrierite from Lovelock, Nevada (U.S.A.), were investigated using a combination of “state of the art” experimental methods including optical microscopy, electron microscopy and microprobe analysis, laser ablation-inductively coupled plasma-mass spectrometry (for the trace elements), vibrational spectroscopy, electron paramagnetic resonance, and synchrotron powder diffraction. The chemical-physical properties of these fibrous ferrierites (morphometric parameters, specific surface area, chemical composition with special attention to metals, mainly iron) that prompted adverse effects in vivo were compared to those of the positive carcinogenic standard fibrous erionite-Na from Jersey, Nevada (U.S.A.). The results of our study have demonstrated that, although there are differences in the crystal chemistry and genetic environment, ferrierite samples exhibit outstanding similarities with fibrous erionite samples: both fibrous erionite and fibrous ferrierite may occur in large amounts as microcrystalline fibrous–asbestiform phases in diagenetic rocks with fibers of breathable sizes. For both zeolites, iron is not structural but is associated with impurities lying at the surface of the fibers. Moreover, data useful to understand the surface activity of these fibrous ferrierites were collected. As far as hydrothermal sample is concerned, the EPR data indicate the presence of hydrophilic (SiO-, AlO-, SiOH) and hydrophobic (Si-O-Si) interacting surface groups able to bind the charged CAT1 probes at close sites and attract the probes in the water pools formed into the fiber aggregates. A high percentage of CAT1 probes weakly interacting with the surface due to competition with metal ions were observed for surface of the diagenetic sample. CAT8 probes were less adsorbed by its surface if compared to the diagenetic sample but the more charged surface provided a stronger binding strength for the diagenetic sample compared to the hydrothermal one. In summary, the results of this study indicate that fibrous ferrierite may represent a potential health hazard and, applying the precautionary principle, it should undergo a procedure of toxicity testing. [ABSTRACT FROM AUTHOR]

The thermal behavior of a woolly erionite-K sample (Lander County, NV, USA), chemical formula (Ca2.03Na0.73K2.52 Mg0.26)[Al8.22Si27.78O71.80]·35.94H2O, was investigated in the 303-1173 K thermal range by in situ X-ray powder diffraction. Present data suggest a general thermally-induced volume contraction whose magnitude increases as Si/ Si+Al ratio becomes smaller. An inverse correlation between Si/ Si+Al ratio and Tdehydr is observed because higher Si/ Si+Al ratio values are associated to lower dehydration temperatures. A positive dependence exists between Si/ Si+Al ratio and Tbreak. A higher Si content results in a greater thermal stability, in agreement with the general trend observed in zeolites. On the contrary, no correlation has been found between Tbreak and weighted ionic potential (Z/r)wt as suggested by reference data. Heating produces a general depletion of the Ca1, Ca2, Ca3, and K1 sites, which is counterbalanced by an increase of the K2 site scattering, even though the latter is not populated at RT. No "internal ion exchange" mechanism was apparently acting in the present sample differently from other erionite samples analysed in the past. At 303 K approximately 20 e- allocated at the OW H2O sites might be assigned to (extra-framework) EF cations. Such fraction increases due to their migration from the extra-framework cation sites following the same mechanism reported in reference data. [ABSTRACT FROM AUTHOR]