NH8.3

Erionite is a fibrous zeolite found in the rock beneath parts of Auckland, New Zealand. As a known carcinogen that can be easily inhaled. it has been linked to the development of mesothelioma. It has a high degree of carcinogenicity due to the specific physical dimensions of the fibres, with certain sizes able to easily deposit deep in the lung tissue once inhaled. This project seeks to understand the extent to which erionite, once exposed, propagates in the ambient air in the form of dust and airborne fibres. The research is made challenging by the lack of standard methodological approaches to detect and quantify such fibres in airborne samples. Initial monitoring has been targeted on areas that have the combined attributes of rapid urban development (and thus excavation) and a confirmed presence of erionite in the rock strata beneath. The key sampling periods will be during the New Zealand summertime when warm temperatures and drier conditions prevail, increasing the potential for dust and fibre generation and buoyancy. The research findings from this project aim to develop a standard method for investigating erionite fibres in ambient air, including recommendations for the use and application of suitable screening methods, instrumentation and field site choice and instrument network density for given scenarios.

How to cite: Talbot, N., Dirks, K., Davy, P., Patel, H., Fan, W., Brook, M., and Salmond, J.: Searching for fibrous erionite in air and dust samples across an urban Southern Hemisphere airshed, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3401, https://doi.org/10.5194/egusphere-egu22-3401, 2022.

The popularity of engineered stone (ES), alternatively known as artificial stone, as a building material for kitchen and bathroom benchtops in residential houses has expanded rapidly over the last decade. This has been associated with a global increase in occupational lung disease in workers exposed to the respirable dust produced during fabrication of ES products. In this study, we evaluated the reactivity and subsequent oxidative reduction potential of ES dusts generated by dry-cutting different ES materials using a common fabrication tool in a controlled environment and subsequently applying these freshly generated dusts to a cell-free deoxyguanosine hydroxylation assay to assess the potential for oxidative DNA damage. The objectives of this study were to (1) compare the potential for oxidative damage by (i) engineered vs. natural stones, (ii) settled vs. respirable stone dust fractions and (2) assess the effect of ageing on the reactivity of freshly-generated stone dust. Engineered stone dust was found to exhibit a higher relative reactivity than the majority of natural stones tested.  Respirable dust fractions were found to be significantly more reactive than their corresponding settled fraction (p<0.05), across all stone types and samples. However, settled dusts still displayed relatively high reactivity overall. No significant change in respirable dust reactivity was observed for three ES samples over a 21-day period; whereas a significant decrease in reactivity was observed in the natural stone studied. These results indicate that ES dusts are able to maintain their relatively high reactivity for extended time periods and settled dust fractions remain a significant hazard if resuspended within the workplace. This study has practical implications for dust control and housekeeping in industry, risk assessment and management.

How to cite: Thredgold, L., Ramkissoon, C., Kumarasamy, C., Gun, R., Rowett, S., and Gaskin, S.: Assessing the oxidative damage potential of engineered stone dust using a deoxyguanosine assay, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13020, https://doi.org/10.5194/egusphere-egu22-13020, 2022.

The toxicity of fibrous minerals is usually evaluated only in the case of biopersistent minerals because they can remain in the lungs or in other biologic environments for a long time causing several illnesses. Very scarce knowledge exists, at the date, on the accurate chemical composition and the effect of particulates and fibres with high solubility (in water and biological environments). To reduce this lack, natural fibrous epsomite from Perticara Mine (Central Italy) was investigated through SEM-EDS, XRPD, ICP-AES and alpha spectrometry measurements. The morphological and morphometrical investigations on the epsomite sample highlight the presence of a significant number of small fibres potentially inhalable for humans, with an equivalent aerodynamic diameter (D_ae) value of 5.09 μm. Moreover, toxic elements (As, Co, Fe, Mn, Ni, Sr, Ti, Zn) and radioactive isotopes (²¹⁰Po and ²²⁸Th) were detected in the epsomite fibres by chemical analysis. In particular, a surprisingly high amount of of ²¹⁰Po (5.59 Bq/g) was detected in the investigated epsomite sample. The first results of this study were recently published by Giordani et al. (2022). Due to the high solubility of epsomite at lung conditions (37 °C and 100% relative humidity; Chipera and Vaniman, 2007), the inhaled fibres rapidly became a solution and can be potentially adsorbed from all parts of the respiratory tract. Consequently, the entire cargo of hazardous elements could be quickly released into the lung environment and thus affect human health. Natural epsomite is a widespread mineral (e.g., in mines, geological outcrops, mineral springs, efflorescence) and has several applications (Ruiz-Agudo et al., 2008).

Our findings suggest great caution in handling epsomite samples, and our work can be considered a representative case study to investigate the interaction between soluble minerals and human health. These preliminary results can be the basis for further studies on the content of hazardous elements in building materials and regarding toxic elements interaction with humans.

Giordani, M., Meli, M. A., Roselli, C., Betti, M., Peruzzi, F., Taussi, M., Valentini, L., Fagiolino, I. and Mattioli, M. 2022. Could soluble minerals be hazardous to human health? Evidence from fibrous epsomite. Environmental Research, 206, 112579. https://doi.org/10.1016/j.envres.2021.112579

Chipera, S.J., Vaniman, D.T., 2007. Experimental stability of magnesium sulfate hydrates that may be present on Mars. Geochimica et Cosmochimica Acta 71, 1, 241-250. https://doi.org/10.1016/j.gca.2006.07.044.

Ruiz-Agudo, E., Putnis, C.V., Rodriguez-Navarro, C., 2008. Interaction between epsomite crystals and organic additives. Crystal Growth and Design, 8(8), 2665-2673. https://doi.org/10.1021/c

How to cite: Giordani, M., Meli, M. A., Roselli, C., Betti, M., Peruzzi, F., Taussi, M., Valentini, L., Fagiolino, I., and Mattioli, M.: Characterization of natural 210Po-rich fibrous epsomite and possible risks to human health, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2486, https://doi.org/10.5194/egusphere-egu22-2486, 2022.

Although in the last 30 years mineral fibres have been the subject of intensive toxicological studies, the actual mechanisms by which mineral fibres exert cytotoxic activity are not fully understood. In this scenario, our work focuses on the monitoring of the very early steps of the interaction between chrysotile, crocidolite and erionite fibres (classified as carcinogenic by the International Agency for Research on Cancer) and macrophages using time-lapse video microscopy coupled with in vitro assays (i.e. LDH cytotoxicity, MTT viability, ROS generation and annexin-FITC/PI apoptosis). All tests were performed on the THP-1 cell line, differentiated into M0 macrophages (M0-THP-1), after acute exposure (8 h) to 25 μg/mL of mineral fibres. Erionite fibres exhibit early toxicity effects while the cytotoxicity induced by chrysotile and crocidolite fibres occurs with a slight delay (ca. 2 h). In concert with literature data, the toxicity of chrysotile and crocidolite is linked to their ability to stimulate Reactive Oxygen Species (ROS) production. ROS are generated by M0-THP-1 cells as a result of frustrated phagocytosis induced by the long asbestos fibres, or produced by asbestos through the redox-active Fe on the fibre surface and metals released into the cell medium as a consequence of the partial dissolution of the fibres. Erionite fibres are able to induce an intracellular ROS increase but this contribution is significantly lower than both crocidolite and chrysotile stimuli. In the short period, crocidolite and chrysotile trigger significant apoptotic phenomena in M0-THP-1 cells while fibrous erionite is associated with early cytotoxicity and probably necrotic-like effect. Because the erionite fibres are short in length, frustrated phagocytosis plays a limited role in the acute toxicity of this fibre. Investigations focused on the intracellular concentrations of Na⁺ and Ca²⁺ as a result of cell-fibre interaction suggest an alternative mechanism by which fibrous erionite may induces cell injury and cell death. During phagocytosis erionite fibres quick exchange their extra-framework Na⁺ with the ions present in the cytosol of M0-THP-1 cells leading to the dysregulation of ionic homeostasis, cell swelling and cell lysis. At the same time, engulfed erionite fibres can reduce the level of cytosolic Ca²⁺ and interfere with endoplasmic reticulum-mitochondria crosstalk causing a delay in M0-THP-1 induction of apoptosis.

How to cite: Di Giuseppe, D., Scarfì, S., Alessandrini, A., Bassi, A. M., Mirata, S., Almonti, V., Ragazzini, G., Mescola, A., Filaferro, M., Avallone, R., Vitale, G., Scognamiglio, V., and Gualtieri, A.: New insights into the cytotoxicity of mineral fibres: A combined time-lapse video microscopy and in vitro assays study of chrysotile, crocidolite, and erionite fibres, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-836, https://doi.org/10.5194/egusphere-egu22-836, 2022.

Chrysotile, one of the six regulated asbestos minerals, is the most employed and commercialized one for industrial applications, thanks to its outstanding technological properties. As of today, asbestos is banned in more than sixty countries worldwide, but the mining and use of chrysotile is still permitted in many other countries. Carcinogenic to humans, asbestos is currently deeply examined in toxicological research aimed at understanding the complex multistep process of asbestos-related carcinogenesis. In the toxicity and pathogenicity of asbestos fibres, the biopersistence plays a key role. In addition, the release of toxic trace metals from the crystal structure during the dissolution of the fibres in the lungs is strictly related to the surface reactivity of the fibres and to the prompt ROS formation, inducing an acute cytotoxicity. Although chrysotile is characterized by a relatively low biodurability, adverse effects with early carcinogenic signs are to be considered.

In the characterization of chrysotile asbestos and its intergrown mineralogical species, micro-Raman spectroscopy is an effective tool for the identification of asbestos fibres and impurities even at trace level, whose occurrence is under the detection limit of other analytical techniques. An extensive micro-Raman characterization was carried out on chrysotile from different mining locations - i.e. the abandoned mine of Balangero (Turin, Italy) and the active Orenburg Minerals mine near Yasniy (Russia). In addition to the identification of the chrysotile structure, impurities of other fibrous or lamellar species consisting of balangeroite and antigorite were easily recognized by their characteristic Raman spectra. Within the fibres, traces of Cr as toxic metal were confirmed by the characteristic photoluminescence peaks of Cr³⁺ emissions, located at about 680 nm. Furthermore, micro-Raman investigations, combined with SEM-EDS analyses, enables the identification of micrometric crystals – even of a few microns - of several Fe compounds, whose eventual dissolution in the organic environment should be carefully considered. Besides magnetite (Fe₃O₄) as the most abundant Fe compound, other Fe oxides and oxyhydroxides were identified, including hematite (α-Fe₂O₃), lepidocrocite (γ-FeOOH) and akageneite (β-FeOOH). Further Fe-bearing compounds include Fe sulphides, also containing Ni as toxic metal. Mackinawite (Fe^IIS) was detected by micro-Raman analysis in both nanocrystalline and partially oxidized forms, suggesting the presence of both Fe(II) and Fe(III) species. Nanocrystalline mackinawite is characterized by an intense sharp peak at ~280 cm^-1 and a weak contribution at ~204 cm^-1, whereas partially oxidized one is distinguished by Raman modes at ~122, 168, 253, 309, 323 and ~355-360 cm^-1. Unlike Fe oxides, whose solubility in the organic environment in typically scarce, the rapid dissolution of Fe sulphides - such as mackinawite - may exhibit the so-called “Trojan-horse effect”, contributing to the acute toxicity of chrysotile. The presence of these micro-crystals should be considered in the release of metals in the reactivity of chrysotile fibres in the lungs. Micro-Raman spectroscopy was successfully proven as a quick and reliable technique to identify inorganic micro-crystals dispersed in chrysotile fibres.

How to cite: Bersani, D., Fornasini, L., Raneri, S., Mantovani, L., Scognamiglio, V., Di Giuseppe, D., and Gualtieri, A. F.: Micro-Raman investigation on Fe-bearing impurities in chrysotile fibres, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8515, https://doi.org/10.5194/egusphere-egu22-8515, 2022.

Nowadays, the toxicity of asbestos mineral fibres is undeniable and well known. It is worthnoting that the mechanism by which these fibers induce adverse effects on human health is not completely understood yet. Major difficulties are related to the wide variability in size, bio durability, molecular arrangement, surface reactivity and chemistry of asbestos fibers. Moreover, the toxicity degree of these hazardous minerals can be further increased by the presence of potential toxic elements (PTEs), especially heavy metals hosted in the fiber lattice.

The present contribution deals with determination of PTEs amount in some tremolite asbestos and actinolite asbestos samples from Episcopia and San Severino Lucano villages (Basilicata region, Southern Italy), in order to assess their potential toxicity.

Micro X-Ray Fluorescence (µ-XRF) and Inductively Coupled Plasma spectroscopy with Optical Emission Spectrometry (ICP-OES) techniques have been used to quantify the concentration of major, minor (Si, Mg, Ca, Al, Fe, Mn) and trace elements (Ag, As, Ba, Be, Cd, Co, Cr, Cu, Li, Mo, Ni, Pb, Sb, Sn Sr, Ti, Te, V, W, Zn, Zr), with the aim of providing a contribution related to the asbestos toxicity knowledge up to now. Specifically, among minor elements, high amounts of Fe and Mn were found in the studied samples. As far as trace elements are concerned, results revealed high concentrations of Cr and Ni in both the studied samples, thus suggesting high toxicity character of the fibers.

Depending on the pseudo-total PTEs concentrations in either tremolite and asbestos samples, it is possible to speculate that some fiber samples are  more toxic than the other one, inducing adverse effects on human health and environment at various extents. Indeed, PTEs transported through asbestos in the air, water and soils come in contact with the human body and therefore can represent a source of risk to human health.

How to cite: Punturo, R., Ricchiuti, C., Bloise, A., Pinizzotto, M. R., and Cantara, C.: Tremolite and actinolite asbestos as micro-reservoirs for Potentially Toxic Elements (PTEs) : implications for human health, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8801, https://doi.org/10.5194/egusphere-egu22-8801, 2022.

Volcanic ashes from the Pomici di Avellino (PdA) eruption, an Early Bronze Age (ca. 3.9 ka BP) Plinian event from Somma-Vesuvius, had a wide dispersal area including most of the Central-South regions of Italy. The finest fraction of volcanic ashes can impact the human respiratory apparatus and induce severe respiratory difficulties and pathologies. Particle size, shape and composition, as well as surface reactivity are the key properties that define health hazard of volcanic ashes. Recent studies evidenced that volcanic ashes could generate significant amounts of free radicals. The particle-derived free radicals can contribute, together with the reactive species (ROS) produced by the cells, to the onset of oxidative stress. To evaluate the potential health impact of volcanic ashes both in proximal and distal areas we examined some physical and chemical characteristics of PdA ashes that may play a role in the onset of adverse health effects. Specifically, the particle size distribution (PSD) and surface properties (the specific surface area (SSA), the mobilization of bio-accessible iron ions and the ability to generate hydroxyl radicals) of PdA ashes have been measured.    

PSD was obtained by automated image analysis coupled with electron microscopy. Bio-available iron was quantified using specific iron chelator and colorimetric reactions. The physisorption of N₂ at 77 K (N₂ BET method) was used to measure the specific surface area. Electron Paramagnetic Resonance (EPR) coupled with spin trapping technique was used to quantify the ·OH radical generation.  

The results show a high surface area value, the presence of an amount of removable iron, and a reactivity in the formation of hydroxyl radicals. Furthermore, the ·OH radical generation is continuous in time. In particular, PdA volcanic ashes reactivity is probably related to the presence of surface bio-accessible iron, which is able to generate free radicals. Thus, free radical generation could make Mt. Vesuvius ashes potentially toxic and threaten people’s health causing respiratory problems. Overall, the physico-chemical characteristics of ash particles from Somma-Vesuvius might pose a significant health hazard even in distal areas, where the transport and the inhalation of fine-grained ashes from explosive eruptions might cause respiratory diseases. In light of these new data, further investigation (e.g. crystalline silica amount) to assess Somma-Vesuvius ashes toxicity is required.

How to cite: Fernandez, G., Giaccio, B., Pacella, A., Sottili, G., Tomatis, M., and Turci, F.: Assessing the surface reactivity of volcanic ashes in view of their potential respiratory hazard: the Pomici di Avellino eruption (3.9 ka BP), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-12527, https://doi.org/10.5194/egusphere-egu22-12527, 2022.

Microplastics (MPs) are emerging pollutants exhibiting a wide range of morphologies, sizes, and visual properties (Lusher et al., 2020). They are found in the environment in different forms such as pellets, i.e., spherical beads, films, foams, fragments, fibres, etc. Microfibres are the most frequently reported in literature (Arienzo et al., 2021). Microplastics can vehicle xenobiotics on their surface including persistent inorganic and organic pollutants. Contaminants and pathogens are collected and transmitted to biota aggravating their toxicological profile (Arienzo et al., 2021). Once generated, MPs may travel along oceans and finally be trapped in marine sediments, the ultimate sink (Harris 2020). Microplastics are present in the environment as result of disruption of primary sources like microbeads, secondary sources like synthetic fibers or due to weathering and breakdown of larger plastic pieces. Weathering is the result of chemical transformations and/or mechanical stresses such as wind, water flow, or corrasion. These transformations are known to cause changes in the plastic's performance such as increased brittleness and discoloration (Hebner and Maurer-Jones, 2020). For these reasons, microscopical analysis of samples is largely employed in microplastic research protocols, usually starting with an initial isolation followed by morphology recognition (Lusher et al. 2020). Visual classification is essential in supporting the various methods and can assist in reducing potential shortcomings of these methods. This study focuses, for the first time, on microplastic distribution in marine sediments, specifically in four submerged and two emerged sand samples of the Posillipo coast, NE of Naples City, in the homonymous gulf. The study is focused on microplastic distribution in marine sediments comparing submerged and emerged samples, highlighting the correlation occurring between sand particles dimensions. Counting and morphological characterization was performed by an original approach, without any pre-treatment of the specimens. Three grams of sample were manually quartered in a controlled environment and homogeneously distributed in glass capsules to allow easy morphological identification and counting. Based on Lusher et al 2020, four descriptive categories were used to aid in visual descriptions of microplastics: morphology (size, shape, texture), optical properties (color, reflectivity), behavior (flexibility), and surface roughness. The procedure also helped the identification of microplastics linked to sediments, and the exploration of microplastic surface for presence of biological or chemical pollutants. Morphological data from optical microscopy assay were used for subsequent SEM analysis of the selected microfibers to confirm the presences of contamination. Morphological data evidenced the presence only of microfibers with different sizes, textures (fiber bundle, single, string), color, and reflectivity, especially in submerged sediments. Moreover, microfibers appeared to be bound to sediments particles, 3% and 13% in two samples. SEM showed alterations on the microfibers surface and local presences of microplastic beads. To fully characterize the studied sediments, mineralogical and micro-Raman analyses along with a particle size classification were also carried out. This analytical procedure represents a preliminary approach to the study of MPs in marine and continental sediments finalized to better address further investigations required to carefully characterize these emerging pollutants.

How to cite: Rossi, M., Capasso, F., Rasulo, A. A., Pretto, P., Langella, A., Izzo, F., Donadio, C., Vergara, A., Albanese, S., Arienzo, M., Ferrara, L., Fraterrigo Garofalo, S., Fiore, M., Fino, D., and Tommasi, T.: First results on microfibers in marine sediments from the Gulf of Naples, Italy, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10230, https://doi.org/10.5194/egusphere-egu22-10230, 2022.

Studies on naturally occurring asbestos (NOA) and on the relevant geo-environmental problems have been traditionally focused on metamorphic rocks (and, more recently, on magmatic rocks). Besides these 'primary' occurrences (i.e., those realted to the in situ growth of NOA minerals), 'secondary', detrital NOA may occurr in sediments, sedimentary rocks and soils derived form the erosion of 'primary' NOA bearing rocks.
The occurrence of detrital NOA in sediments and soils is increasingly recognized worldwide. However, a few studies exist that investigate the 'sedimentology of NOA', i.e., the mechanisms underlying the genesis, transport, deposition and post-depositional modifications of detrital NOA particles in the different sedimentary environments. A better understanding of these mechanisms would give us the tools to predict the presence and possible concentration of detrital NOA in sediments and sedimentary rocks.
The occurrence and distribution of detrital NOA within the Oligocene-Miocene succession of the southern Tertiary Piemonte Basin (NW Italy), will be investigated as a scientific development in the frame of the CARG project (Geological Mapping at 1:50,000 scale - sheet 195 Novi Ligure). This succession consists of stratigraphic units rich in ophiolite clasts and deposited in a variety of sedimentary environments, from continental to deep marine, thus representing an ideal study case. 

How to cite: Barale, L., Avataneo, C., Compagnoni, R., Cossio, R., d'Atri, A., Gomiero, C., Piana, F., and Turci, F.: Naturally Occurring Asbestos (NOA) in sediments: state of the art and perspectives, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-11397, https://doi.org/10.5194/egusphere-egu22-11397, 2022.

In the Pollino Massif, in the southern Apennines, the asbestos minerals bearing serpentinites are widely exposed at several quarries (Pietrapica quarry, Timpa Castello quarry, Fagosa quarry and Ghiaia quarry), whose material was extracted and used as aggregates for construction, filling and embankments, and as ornamental stones. Airborne asbestos can be the result of extraction procedure as the stacking, storing and grinding of the serpentinites, so due to the environmental concerns the quarries have been abandoned. In the Pollino Massif serpentinites represent the lherzolitic to harzburgitic upper mantle basament of the Internal Liguride sequence of southern Apennines and can be classified as cataclastic and massive (Dichicco et al., 2015). Cataclastic serpentinites are fractured and deformed whereas those massive show a low fracturing and deformation. The serpentinites have homogeneous mineral compositions and are mainly composed by serpentine polimorphous, asbestiform tremolite, followed by actinolite, chlorite, magnetite and Cr-spinels, and subordinatly calcite, dolomite, and clay minerals. Further, edenite, currently not regulated by the Directive 2003/18/EC of the European Parliament and of the European Council of 27th March 2003, has been recently also detected for the first time (Dichicco et al., 2019). Serpentinite rocks can release significant amounts of fibers of hazardous minerals for the human health, into the air, water and soil, either through geogenic weathering processes or human activity. The observed fibers in the outcrops are of two types: 1) large and elongated fibers that occupy the entire surface of the rock; 2) tiny fibers forming a network throughout the rock.

The aim of this work is to characterize in a detailed way the asbestos minerals of representative serpentinite samples taken from the four quarries using the combination of different analytical techniques: field surveys, X-Ray powder diffraction (XRPD), scanning electron microscopy combined with energy dispersive spectrometry (SEM/EDS), µ-Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) in order to assess the impact on the environment and public health.

References:

Dichicco, M.C.; Laurita, S.; Paternoster, M.; Rizzo, G.; Sinisi, R.; Mongelli, G. Serpentinite Carbonation for CO₂. Sequestration in the Southern Apennines: Preliminary Study. Energy Procedia 2015, 76, 477-486.

Dichicco, M.C.; Paternoster, M.; Rizzo, G.; Sinisi, R. Mineralogical Asbestos Assessment in the Southern Apennines (Italy): A Review. Fibers 2019, 7, 24.

How to cite: Rizzo, G., Buccione, R., De Bonis, A., Paternoster, M., and Mongelli, G.: Characterization of asbestos minerals in serpentinites quarries in the Pollino Massif (southern Apennines, Italy), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-13253, https://doi.org/10.5194/egusphere-egu22-13253, 2022.

The “Geological map of Naturally Occurring Asbestos of Piemonte region” at 1:250,000 scale aims at reviewing the distribution of NOA-bearing rocks and the individual occurrences of NOA minerals of Piemonte at the regional scale. 

A geo-lithological basemap was produced ad hoc through a reasoned simplification of the basic Geological Map of Piemonte and its geo-database (GeoPiemonteMap, Piana et al., 2017; also available as a WebGIS service at https://webgis.arpa.piemonte.it/Geoviewer2D/index.html?config=other-configs/geologia250k_config.json). Particular emphasis was given to the potentially NOA-bearing rocks, i.e., meta-ophiolites and sedimentary successions containing meta-ophiolite clasts. The map reports hundreds of punctual occurrences of NOA minerals, as well as the main former asbestos mining sites. The NOA occurrences dataset derives from a thorough revision of the regional geological literature, integrated with authors' original data acquired during several years of geological and geo-environmental surveys.

The map is supported by a geo-database, compliant with the geo-datsabase of basic Geological Map of Piemonte. Each mapped NOA occurrence corresponds to an item of the geo-database, containing the following information: NOA mineral(s) species, locality and coordinates, occurrence type (i.e., in vein/in the rock matrix/detrital), host rock lithology, meso- and micro-scale description (e.g., vein thickness, associated minerals, etc.), NOA mineral identification method (e.g, optical microscopy, microRaman spectroscopy, XRD, etc...), bibliographic reference, and sample availability (i.e., presence of samples in university or museum collections).

References:
Piana et al. (2017), Journal of Maps 13: 395-405, DOI: 10.1080/17445647.2017.1316218

How to cite: Piana, F., Barale, L., Compagnoni, R., and Turci, F.: GeoPiemonte NOA: a geological map of naturally occurring asbestos in Piemonte region (NW Italy), EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-9913, https://doi.org/10.5194/egusphere-egu22-9913, 2022.

The occurrence of asbestos and asbestos-like minerals in natural sites may pose a risk to human health and the environment when rocks and soils are mobilized. Weathering and anthropic activities favour the liberation of potentially hazardous Elongated Mineral Particles (EMP, NIOSH 2011). The definition of EMP includes both asbestos and other fibrous minerals. The latter share several physical-chemical properties with asbestos, but their toxicological profile is still unknown. The assessment of risk requires the quantification of the occurrence and the estimation of the potential emissivity of EMP from the hosting matrix.

We quantitatively described the potency of a rock to disperse EMPs in the environment with a quantitative parameter namely the “liberability factor” (Lf). Lf was measured for 40 meta-ophiolite fragments from the NOA-bearing units of Liguria (Voltri Group and Sestri-Voltaggio Zone) and Calabria (Gimigliano-Monte Reventino Unit, Southern Ligurian Domain). The mineral–petrographic characterization of these rocks showed the presence of veins of chrysotile, fibrous tremolite-actinolite, fibrous sepiolite and fibrous antigorite.

By adapting the UNI EN 12457-2:2004 method for solid waste, we designed a weathering simulation test to quantify the EMPs and the fibres (according to the World Health Organization) possibly liberated by applying to the rock a standardized mechanical stress. Waterborne EMPs were filtered on membranes and counted by electron microscopy (SEM-EDS), by adapting the Italian Regional Agency for the Protection of the Environment (ARPA) procedure for waterborne asbestos (ARPA Piemonte, 2016). We obtained Lf values as the number of waterborne fibres suspended per unit volume of water (fibres/Litre). All analysed rock samples showed Lf values ranging from 30 Mf/L to 21’000 Mf/L. Chrysotile, tremolite, sepiolite, and antigorite, with asbestos-like habit, were detected.

Lf proved to be a reliable, easy to use method for the characterization and prediction of EMP and fibre dispersion in the environment from NOA-bearing rocks subjected to a standardized mechanical stress. This study is part of the BRIC 2019 project (grant number ID 57.1) supported by INAIL (Italian National Institute for Insurance against Accidents at Work).

References

• ARPA Piemonte 2016. U.RP. M842 rev.03. Asbestos in water by Scanning Electron Microscopy.
• NIOSH, 2011. Asbestos fibers and other elongate mineral particles. Current Intelligence Bulletin 62.
• WHO, 1997. Determination of Airborne Fibre Number Concentrations. ISBN 92 4 154496 1

How to cite: Gomiero, C., Barale, L., Giustetto, R., Pacella, A., Piana, F., Campopiano, A., Turci, F., and Petriglieri, J. R.: A new experimental method to predict the dispersion of Elongated Mineral Particles in the environment, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5363, https://doi.org/10.5194/egusphere-egu22-5363, 2022.

The World Health Organization defines asbestos as fibers with a length (L) ≥ 5 μm, a diameter (D) < 3 μm and L/D ratio > 3. When talking about hazards related to mineral fibers and asbestos, the general concern focuses on workers at quarries, extracting the material. However, there are historic buildings and monuments built on rocks containing these fibers (e.g. serpentinite, soapstone) that due to their artistic interest or links to the architectonic heritage may need to be cleaned at some point for restoration reasons. In this sense, laser cleaning is being more and more widely used in restoration. Although, in general, it is a very selective and controllable technique that allows the removal of fine layers of material (different types of crusts or patinas) with hardly any effect on the rock substrate, laser cleaning activities on this kind of fibrous materials can generate a potentially hazardous dust that, if not protective actions are taken, may affect the heath of workers, that can be from technicians to artists to scientists developing cleaning tools. Regarding the latter, we have arranged an experiment to test how much of this powder can be retained in a “homemade” filter, coupled to a laser equipment. The idea is to work with a laser in the same way a worker on restoration would do to clean a building made of, for example, serpentinite, and observe the fibers that are retained by the filter. Combination with other tools like petrographic and electronic microscopy can be used for the sake of human health.

How to cite: Pereira, L., López, A. J., and Ramil, A.: Mineral fibers in restoration work. Looking for avoiding health problems., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1923, https://doi.org/10.5194/egusphere-egu22-1923, 2022.

Particle research in harbour areas typically focuses on ship (stack) or vehicular exhaust emissions, while high particle emissions may also occur from other harbour operations such as vessel refurbishment activities. The literature regarding these activities is scarce, especially in terms of particle chemical composition and toxicity.

The aim of this work was to characterize the chemical composition and toxicity of particles released during vessel refit operations. Airborne particle samples were collected inside the tents where abrasion of primer and top-coat paints with mechanical abraders took place in the Mallorca shipyard (Spain), during two experimental campaigns. On-line and offline aerosol instruments were placed at different monitoring locations to measure particle mass concentration and number concentrations, particle size distribution, chemical composition, morphology and cytotoxicity. Aerosol chemical composition of PM0.25, PM2.5, PM4 and PM10 was characterized using impaction cyclones. ELPI was used to obtain a more detailed composition from 0.006 μm to 10 μm. PM2 aerosols were sampled with a Biosampler, and in vitro analysis was performed with A549 lung cells. Particle morphology was determined by TEM. The dustiness index of the powders generated was determined using the rotating drum method (EN15051-).

Release of coarse, fine and ultrafine particles, including engineered nanoparticles, was evidenced during both campaigns. Aerosol composition was linked to the primer’s composition, with main tracers Ti (270 μg/m³ as mean during the daily shift), Mg (177 μg/m³) and Al (54 μg/m³) in PM10 aerosols. Different particle morphologies and tracers were observed by TEM which related to the main chemical components analyzed. On the TEM grids, particle sizes ranged between <50nm and >2000nm in diameter. In addition to the coarse, fine and ultrafine particles formed incidentally and emitted during abrasion of the primer and top-coats, the presence of markedly regular nanoparticles was also detected, which seemed to be engineered (ENPs) and probably used as nano-additives in the coatings (Miller et al., 2020). The ENP detected in the shipyard samples showed characteristic triangular and hexagonal shapes, as well as other polygonal shapes, and were detected as single nanoparticles with diameters <50 nm as well as embedded in larger aggregates formed by the major components of the coatings. In vitro assessments (MTT assay) indicated only moderate particle cytotoxicity. However, the results indicated potentially high oxidative stress, which showed differences across the different sampling days but which could not be directly linked to any specific activity (e.g., mechanical or manual abrasion sanding, spray-painting, …) due to the large mix of aerosols inside the tent. Overall, it was concluded that particles release during refit operations in shipyards have the potential to impact human health and that of the aquatic environment, and should thus be carefully monitored and regulated.

Acknowledgement: This work was carried out in the framework of project IDAEALPORT (RTI2018-098095-BC21).

Reference: Miller, R. J., Adeleye, A. S., Page, H. M., Kui, L., Lenihan, H. S., & Keller, A. A. (2020). Nano and traditional copper and zinc antifouling coatings: metal release and impact on marine sessile invertebrate communities. Journal of Nanoparticle Research, 22(5). https://doi.org/10.1007/s11051-020-04875-x

How to cite: López Olivé, M., Ribalta, C., Pérez Albaladejo, E., Porte, C., Romero Sáez, F., Ballesteros, A., Fito, C., Monfort, E., and Viana, M.: Environmental release of engineered nanoparticles from shipyard activities., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3925, https://doi.org/10.5194/egusphere-egu22-3925, 2022.

Because of the tremendous development of nanotechnologies and the subsequent potential exposure of humans to nanomaterials, nanotoxicology is a rapidly evolving research field. In a context of health risk assessment the biological monitoring (or biomonitoring) of nanoparticles in human biological samples could be a particularly useful approach to get new insights into the role of inhaled biopersistent nanoparticles in the etiology/development of some respiratory diseases. Biomonitoring has been widely used in pulmonology, especially in the case of pneumoconiosis. It can bring critical information on the relationship between exposure to a harmful substance and biological/pathological effects.

Our objective was to investigate the relationship between the biomonitoring of nanoparticles in patients’ broncho-alveolar lavages (BAL), interstitial lung diseases and occupational exposure to these particles released unintentionally.

We conducted a clinical trial on a cohort of 100 patients suffering from lung diseases (NanoPI clinical trial, ClinicalTrials.gov Identifier: NCT02549248). We separated micron-sized particles (>1 µm) from submicron (100 nm-1 µm) and nano-sized particles (<100 nm) contained in BAL from patients who suffered from interstitial lung diseases (ILD). We then determined the metal load in each of these size-fractions. We evidenced a concentration of submicron silica particles higher in patients suffering from sarcoidosis than in patients suffering from other ILD, suggesting a potential role of these inhaled particles in the etiology and/or development of sarcoidosis. Similarly, we observed a concentration of titanium nanoparticles higher in patients suffering from idiopathic fibrosis than in patients suffering from other ILD allowing suspecting a relationship between titanium nanoparticles and idiopathic pulmonary fibrosis. To complement mineralogical analyses of BAL and offer a comprehensive vision of the events from exposure to airborne nanoparticles to the biological response induced, we investigated associations between respiratory diseases and occupational exposures. To that purpose, we estimated the exposure to inhaled unintentionally released nanoparticles of the patients for each job held in their working life. Most of the patients showed a high probability of exposure to airborne unintentionally released nanoparticles (>50%), suggesting a potential role of inhaled nanoparticles in lung physiopathology. Depending on the respiratory disease, the amount of patients likely exposed to unintentionally released nanoparticles was variable (e.g. from 88% for idiopathic pulmonary fibrosis to 54% for sarcoidosis). These findings were consistent with the mineralogical analyses. Further investigations are necessary to draw firm conclusions but these first results strengthen the array of presumptions on the contribution of some inhaled particles (from nano to submicron size) to some idiopathic lung diseases.

How to cite: Forest, V., Pourchez, J., Pélissier, C., Audignon Durand, S., Vergnon, J.-M., and Fontana, L.: Relationship between human biomonitoring of inhaled biopersistent nanoparticles in broncho-alveolar lavages, lung diseases and occupational exposure, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8618, https://doi.org/10.5194/egusphere-egu22-8618, 2022.

Kaolin and bentonite, two clays mainly made of kaolinite and montmorillonite, respectively, are largely used in various industrial applications. However, their impact on human health has not been fully investigated and data about their mechanism of cellular toxicity are scarce. In vivo and in vitro studies showed that kaolin and bentonite particles can induce transient inflammation, alveolar proteinosis, and are cytotoxic to a variety of mammalian cells (Wiemann et al. 2020; Maciaszek et al. 2021). We recently demonstrated (Pavan et al. 2020) that a specific sub-population of surface silanols located at a well-defined intersilanol distance, i.e., nearly-free silanols (NFS), is responsible for the membranolytic and inflammatory activity of quartz particles. We hypothesized that a similar structure-activity relationship may exist for kaolinite and montmorillonite particles, since they exhibit tetrahedral SiO₂ layers at their outer surface and hydroxyls groups, i.e., silanols and aluminols, at the crystal lattice boundaries.

Four bentonite (> 90% montmorillonite) and kaolin (> 75% kaolinite) particles were characterized for their physico-chemical properties of toxicological interest and their capacity to damage cellular membranes was assessed using red blood cells as model of membranes. All bentonite and kaolin particles resulted highly membranolytic. As clay minerals may exchange cations with suspending medium and the structural integrity of biological membranes may be compromised by significant alteration of the medium ionic strength, the membranolytic activity of kaolin and bentonite leachates was assessed. Only bentonite leachates induced membrane damage with an effect that was dependent on each sample specific cation exchange capacity (CEC). A reduction or a complete abrogation of kaolin and bentonite membranolytic activity was observed when their surface was coated with dioleoyl lecithin, indicating that surface moieties play a key role for both kaolin and bentonite interactions with membranes. Investigations by IR spectroscopy of the surface-exposed hydroxyl groups revealed the occurrence of NFS, which vibrational feature was especially well defined for kaolin. Thermal treatments carried out on kaolin modified the relative intensity of NFS and its membranolytic activity, suggesting a relationship between NFS and membrane damage.

In conclusion, the capacity of kaolin particles to damage membranes appears related to kaolinite specific surface hydroxylated species. On the other hand, the mechanism of interaction of montmorillonite particles with membranes is function of both mineral surface features and CEC. These findings provide a preliminary understanding of the mechanism of interaction of clay minerals with biological membranes. This interaction may represent the triggering event of kaolin and bentonite adverse cellular effects.

Bibliography

Maciaszek K. et al. (2022) An in vitro assessment of the toxicity of two-dimensional synthetic and natural layered silicates,Toxicol In Vitro, 78:105273

Pavan C. et al. (2020) Nearly free surface silanols are the critical molecular moieties that initiate the toxicity of silica particles, Proc Natl Acad Sci USA, 117 (45):27836

Wiemann M. et al. (2020) Lung toxicity analysis of nano-sized kaolin and bentonite: missing indications for a common grouping, Nanomaterials, 10 (2):204

How to cite: Cananà, S., Chilla, G., Mino, L., Tomatis, M., Lison, D., Turci, F., and Pavan, C.: Do surface hydroxyls drive the membranolytic activity of bentonite and kaolin particles?, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-2280, https://doi.org/10.5194/egusphere-egu22-2280, 2022.

Crystalline silica (CS) is a well-known human toxicant and inhalation of the airborne particles with size lower than 4 µm is associated to severe occupational diseases, such as silicosis and lung cancer.¹ The International Agency for the Research on Cancer (IARC) classified CS as carcinogenic to humans and freshly fractured CS is held to be more toxic than aged dust.^1,2 Fracturing generates on CS a specific family Nearly-Free Silanols (NFS), which are able to destabilize cell membranes,³ and some nanometric particles. We aim here to create and assess the possible toxicological impact and the chemical characteristics of the nanometric fraction (nano-CS) formed when CS is fractured.

A highly pure CS of synthetic origin⁴ (α-quartz, micrometric in size) was ball-milled to obtain ultrafine particles. We coupled a dry milling step and a wet milling step, using water as dispersing agent, and we generated particles with specific surface area (SSA) ranging from 37 to 60 m²/g. These SSA values signaled the generation of a relevant nanometric fraction. The increase in SSA paralleled the energy delivered to quartz during the milling, that exceeded by far the energies commonly used in industrial processing. Morphology, crystallinity, size, surface silanols, including quantification of NFS, and membranolytic activity toward red blood cells were assessed. The nano-CS samples exhibited: i) a partial lattice amorphization that increased with the increase of the milling energy; ii) the presence of two distinct domains of scattering that indicated the occurrence of crystallite with nanometric (< 50 nm) and submicrometric (0.8-1 µm) size; iii) a strong tendency to form micrometric agglomerates , which could be partially dispersed with ultrasounds and surfactants in water suspensions; and iv) a moderate membranolytic activity that correlated with the presence of NFS. We selected a nano-CS sample that would be classified as a nanomaterial under EU CLP regulation (>50% of particles in number are < 100 nm).⁵ The nano-CS sample will be used in the next future as a reference material to quantify the nanometric fraction of silica powders and assess the potential exposure to nano-CS in industrial hygiene context.

In conclusion, the preparation and characterization of nano-CS was achieved and the physico-chemical characteristics that could be relevant for silica toxicity were assessed. The nano-CS reference material will be used to quantify nano-CS in industrial scenario, and to clarify the toxic activity of nanometric silica obtained by mechanical fracturing.

[1] IARC, Monograph Vol. 100C, 2012

[2] Turci et al, Part Fibre Toxicol, 2016, 13, 32.

[3] Pavan et al, Proc. Natl. Amer. Soc. USA, 2020, 117 (45), 27836

[4] Pastero et al., 2016, Cryst. Growth Des. 16, 4, 2394–2403.

[5] SCoEaNIHR, E. S., 2010, 'Scientific Basis for the Definition of the Term “nanomaterial”', European Commission.

How to cite: Bellomo, C., Pavan, C., Rebba, E., Fiore, G., Mino, L., and Turci, F.: Preparation and quantification of crystalline nanosilica for toxicological investigations, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5315, https://doi.org/10.5194/egusphere-egu22-5315, 2022.

As the main responsible of pollution, particulate matter (PM) in big cities and industrial sites greatly affects the life quality of an ever-growing number of people all over the world. That situation drives the strong effort for continuous PM monitoring by governmental and environmental protection agencies. Despite great attention to such air quality control, the analysis of particulate is often limited to the study of size distribution and elemental composition giving only few information on the pollutant sources of origin (source apportionment). Information about such sources could assist in the development of strategies towards the reduction of pollutant emissions.

In this framework, we report a novel integrated approach for the qualitative and quantitative analysis of air particulate. The developed method leverages on the integration of different analytical techniques on PM samples such as Scanning Electron Microscopy (SEM), Raman Spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR). The proposed protocol aims both at identifying the main constituents of air particulate identifying at the same time its sources (car wheel, combustion, asphalt, car brake, etc…).

The SEM analysis provides information on the size distribution and elemental composition of the particles, whereas the Raman and FTIR spectroscopy allow for the identification of the actual components. By comparing the results of the analysis with a database of spectra obtained from known samples, PM particles can be associated with a probable source.

Finally, a mapping strategy of air sampling filters for the rough quantification of each component of the particulate via Raman and FTIR spectroscopy will be presented.

How to cite: Giardino, M., Tiano, A., Baietto, O., Janner, D., and Bellopede, R.: An Integrated Microscopy And Spectroscopy Approach For The Characterization Of Air Particulate Matter, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8390, https://doi.org/10.5194/egusphere-egu22-8390, 2022.

We agreed with the question of Oliver C in a recent article in Chest [1] about “Sarcoidosis: An Occupational Disease ?” and we plead for discontinuing the practice of assigning the idiopathic characterization to all cases of sarcoidosis without in depth questionnaire.

Indeed among the three criteria of American thoracic Society to define the sarcoidosis, the third was the exclusion of alternative causes and particularly foreign body reaction. In our Minasarc study [2], we demonstrated that the search for inorganic exposure was largely insufficient: there was no systematic in depth questionnaire about mineral exposome including occupation but also hobbies, and implanted device for example. There was also insufficient search for foreign bodies in granulomas with no polarized light study mentioned.

In a historical perspective we demonstrated that there were blurred boundaries between pneumoconiosis and sarcoidosis and we proposed to mobilize detection means such as scanning electron microscopy coupled with energy dispersive x-ray spectroscopy (SEM-EDX) analysis [3]. In a recent study about Fallopian tube granulomatosis induced by Essure Implant device used for sterilization we demonstrated the better efficiency of SEM-EDX on simple optical microscopy [4].

We demonstrated the same SEM-EDX interest in a woman having been diagnosed lung sarcoidosis thirty years sooner [5] and after a new sub- diaphragmatic biopsy the transmission electron microscopy coupled with EDX analysis identified many steel particles. After deeper inquiry, the patient admitted using, every week end for more than forty years, sand paper and wire brush to polish wood furnitures as a hobby without no protection.

That is why we suggest that the sarcoidosis diagnosis was only admitted after an in depth questionnaire and at less SEM-EDX analysis of the histologic specimen showing granulomatous and epithelioid cells and multinucleated giant cells.

It would not be possible for talking about idiopathic disease without using a standardized, all along life questionnaire about mineral exposure and modern SEM-EDX allowing chemical analysis of foreign bodies identified associated with granulomas.

We propose a paradigm modification on the manner to question the sarcoidosis diagnosis with use of new tools for identifying a new entity of mineral dust induced granulomatosis.

[1] Oliver, LC., Zamke, AM., Sarcoidosis. An occupational study DOI: https://doi;org/10.1016/j.chest.2021.06.003

[2] Catinon, M., Cavalin, C., Chemarin, C., ... & Vincent, M. (2018). Sarcoidosis, inorganic dust exposure and content of bronchoalveolar lavage fluid: the MINASARC pilot study. Sarcoidosis, Vasculitis, and Diffuse Lung Diseases, 35(4), 327.

[3] Vincent, M., Chemarin, C., Cavalin, C., Catinon, M., & Rosental, P. A. (2015). From the definition of silicosis at the 1930 Johannesburg conference to the blurred boundaries between pneumoconioses, sarcoidosis, and pulmonary alveolar proteinosis (PAP). American journal of industrial medicine, 58(S1), 31-38.

[4] Catinon, M., Chemarin, C., Assaad, S.,... & Vincent, M. (2014). Wire brushing wood furniture, granulomatosis and microscopic mineralogical analysis. Sarcoidosis Vasc Diffuse Lung Dis, 31(3), 262-4.

[5] Catinon, M., Roux, E., Auroux, A., ... & Vincent, M. (2020). Identification of inorganic particles resulting from degradation of ESSURE® implants: Study of 10 cases. European Journal of Obstetrics & Gynecology and Reproductive Biology, 250, 162-170.

How to cite: Vincent, M., Roux, E., and Catinon, M.: Sarcoidosis an occupational disease? The need for a mineral dust exposure questionnaire and scanning electron microscopy with EDX analysis, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5077, https://doi.org/10.5194/egusphere-egu22-5077, 2022.

Footing surfaces regularly used in equine riding arenas are composed by mixture of several naturally occurring rocks (specifically sand, silt, and clay), many times with the addition of specific additives (e.g., organic or synthetic fibres, wood, rubber, etc.). The most common and abundant minerals composing the used rocks are quartz, and feldspars; micas, clay minerals, oxides and others may be also present. The mineral composition of the arenas differs depending on the supply quarry, but it also changes in the same arena over time.

During riding and training activities, arena surfaces are strongly trampled by the horse’s hooves, resulting in production of fine and airborne dusts including also respirable crystalline silica (RCS) particles. Horses, equestrian workers, and people frequenting the riding schools for recreational reasons are therefore potentially exposed to respiration of RCS.

Some studies have dealt with the correlation between the horse’s exposure to RCS and consequent bone problems [1]. So far, four cases of lung cancers related with RCS exposures in horse trainers have also been recognized [2].

There are not systematic studies on the characterization of different inorganic particles inhaled by horses, and their possible respiratory consequence (besides silicosis). Little is known about health injuries for humans, both equestrian workers and people frequenting riding arenas.

The aim of this study is to detect what kinds and amount of inorganic particles can be inhaled by horses, distinguishing among RCS species and others, both to evaluate the possible health consequences in this recreative and professional context.

Samples of bronchoalveolar lavage fluid (BALF) of 10 horses have been collected and investigated by SEM/EDS, and TEM/EDS techniques.

The quality and quantity of inhaled inorganic particles present in healthy equine BALF samples were compared with those found in equine BALF samples with chronic inflammatory (asthma-like) lung diseases.

The present study  provides a way to characterize the exposure of horses to RCS. This study could highlight the problem relating to a potential increased exposure risk for RCS, which could lead to the development of occupational lung cancer within the workers in this sector.

The results of this study suggest the need of both further medical assessments and studies to promote awareness within the sector of the exposure risks associated with footing materials used equestrian arenas and the impact of increased knowledge and understanding of the risks involved.

As strategies for health hazard control, i.e. the air concentration reduction of RCS and other inorganic particles, may be the regular arena watering.

In this dynamical context, the horses can be used as sentinel for the human health by a periodic control of the BALF inorganic particles burden.

[1] Zavodovskaya, R.; Stover, S.M.; Murphy, B.G.; Katzman, S.; Durbin-Johnson, B.; Britton, M.; Finno, C.J. Bone formation transcripts dominate the differential gene expression profile in an equine osteoporotic condition associated with pulmonary silicosis. PLoS ONE (2018) 13, e0197459.

[2] Kim, H.R., Kim B, Jo BS, Lee JW Silica exposure and work-relatedness evaluation for occupational cancer in Korea. Annals of Occupational and Environmental Medicine (2018) 30:4

How to cite: Belluso, E., Capella, S., Bellis, D., Bullone, M., Costa, G., and Di Benedetto, F.: Exposure to respirable crystalline silica (and feldpars) in equine riding arenas: non-conventional exposure scenario, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-5995, https://doi.org/10.5194/egusphere-egu22-5995, 2022.

This is a digitalized industrial plant in a continuous line, composed by a low temperature furnace and a high temperature protective atmosphere furnace, connected by a conveyor belt where anthropomorphic robots are used in the loading-unloading of asbestos materials and quality control with devices used in NASA space programs. This invention allows the inertization of asbestos fibers for the recycling of Secondary Raw Material in Powder Metallurgy, for the production of new highly refractory and hard metal alloys, with applications in the field of air and land transport, electrical and electronic engineering, missile engineering, nuclear, aerospace, biomedical, nanotechnologies, for military applications and technologies in defense systems and armaments, precious metals and for the production of refractory material. - Paolo Tuccitto Patent IT. n°30653/2020 and EU N°EP21425060/2021

How to cite: Tuccitto, P.: Digitized Inerting Process in a Protective Atmosphere in a Continuous Line Industrial Plant for the Inertization of Silicates and Asbestos Materials, for recycling in the Powder Metallurgy Industry, in the Aerospace, Arms and Defense Industry., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3815, https://doi.org/10.5194/egusphere-egu22-3815, 2022.

A review of a range of TEM and SEM studies of fibrous amphiboles has been undertaken. Of particular relevance, are TEM studies where fibers were viewed down the fiber axis which identified the following common features to a greater or lesser degree: 1) crystal structure defects & stacking faults, 2) the presence of fiber cross-sectional edges which are rounded, irregular, faceted, or hybrid, and 3) intergrowths with other crystalline phases. Also of relevance are SEM studies where external fiber morphology can be studied in detail. The features identified in these studies have been used by various parties to either include or exclude identified fibers as asbestos. This review contrasts and compares the fiber images presented in the TEM/SEM studies and attempts to summarize the issues and arguments being made by various parties, including mineralogists, regulators, litigators in asbestos injury lawsuits, and others, in the debate as to whether fibrous amphiboles are, or are not, asbestos and to be included during analytical testing.

How to cite: Bailey, R. M.: A review of the range of fibrous amphibole crystal morphologies between asbestiform fibers and cleavage fragments as revealed by TEM/SEM studies and how their interpretation impacts analytical testing results used in asbestos exposure studies., EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-10941, https://doi.org/10.5194/egusphere-egu22-10941, 2022.