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Asbestos research, identification, and quantification have been performed over the years, and the relationship between fiber inhalation and lung disease development is well defined. The same cannot be said for the gastroenteric system: the International Agency for Research on Cancer (IARC) believes that colorectal cancer (CRC) could be associated with asbestos exposure, but research has not demonstrated a casual nexus between exposure and CRC, despite highlighting an association tendency. The combination of scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) is the most applied technique in asbestos fiber identification in tissues and intestinal mucosa. In this study, SEM/EDS was applied to evaluate the presence of asbestos fibers and bodies (ABs) inside the tissue of eleven patients affected by CRC who had undergone environmental exposure due to living in an asbestos-polluted area where an Eternit plant had been active in the past. This technique was coupled with optical microscopy (OM) to verify whether the latter could be applied to evaluate the presence of these mineral phases, with the goal of understanding its suitability for identifying fibers and ABs in colon tissues. In addition to verifying the presence of fibers, this study allowed us to identify the deposition site of said fibers within the sample and possibly detect associated tissue reactions using OM, over a shorter time and at lower costs. Despite being a preliminary and descriptive work, the obtained results allowed us to propose a method involving first-sample OM observation to identify regulated (fibers with a length ≥ 5 μm, a thickness ≤ 3 μm, and a length/thickness ratio > 3) asbestos phases and ABs in the extra-respiratory system. In fact, OM and SEM/EDS provided similar information: no asbestiform morphology or ABs were found, but phyllosilicates and other inorganic materials were identified. This research needs to be continued using higher-resolution techniques to definitively rule out the presence of these fibers inside tissues whilst also increasing the number of patients involved. [ABSTRACT FROM AUTHOR]

In the last few years, an increasing interest has developed regarding the application of different techniques for the identification of pollutants inside the tissues deriving from patients affected by benign or neoplastic diseases. Particular attention was paid to neoplasia linked to particular exposures, e.g., heavy metals, carbon dusts, silica, asbestos. As regards the last pollutant, a wide body of scientific literature has been collected, considering the severe effects caused by mineral fibers on human health. Optical and electronic microscopies were widely applied to identify the fibers in respiratory and extra-respiratory organs to detect the minerals and to link their presence to an exposure source and to understand their role in cancer development. The main advantage of electron microscopy lies in the possibility of coupling the microscopes with energy dispersive spectrometers and also collecting data on the elemental composition of various inorganic phases. In term of sample preparation and time of analysis, the most utilized microscope technique is Scanning Electron Microscopy with an annexed energy dispersive spectrometer (SEM/EDS), allowing for the morphological and chemical characterization of the observed particles/fibers. Moreover, this technique is envisaged by Italian Law for asbestos identification in air and bulk samples. On the other hand, this technique does not allow a reliable identification of the mineral phase in the case of polymorphs with the same chemical formula but different crystal structures. In this work, the coupling of a spectroscopical technique—micro-Raman spectroscopy—to SEM/EDS is proposed for a sure phase identification of particles, showing EDS spectra with ambiguous phase identification, observed in samples of tissues from patients affected by colorectal cancer and living in an asbestos-polluted area. In these tissues, different particles with EDS spectra that do not allow a sure identification of the phase—in particular calcium-rich particles and titanium oxides—were successively analyzed by micro-Raman spectroscopy. Thanks to this last technique, it was possible to ascribe the mineral phases associated to these particles to "aragonite" (a calcium carbonate polymorph) and to "anatase" (a Ti dioxide polymorph). [ABSTRACT FROM AUTHOR]

Asbestos is a term that includes six fibrous mineral phases related to different lung diseases, including asbestosis, lung cancer, and Malignant Pleural Mesothelioma (MPM). Since the last century, these minerals have been widely studied under their mineralogical/chemical and physical aspects with in vivo and in vitro studies to understand the mechanisms of their carcinogenicity. There are several techniques described in the literature, as optical and electron microscopies, for the identification of coated (asbestos bodies, ABs) and uncoated fibers, but only micro-Raman spectroscopy permits a sure characterization of these minerals—and of the related phases—directly in the histological sections of pulmonary parenchyma without any manipulation. In this case, the risk of the loss of associated inorganic phases from asbestos bodies (ABs) and fibers (e.g.: iron or carbonaceous micro-particles) is avoided. Asbestos bodies are produced by the activity of alveolar macrophages with degradation/inactivation of asbestos fibers. Inside the alveolar macrophages, organic and inorganic material settles on the foreign fibers forming an iron-rich proteic and carbonaceous coating. In this study, Variable Pressure Scanning Electron Microscopy with annexed Electron Dispersive Spectroscopy (VP-SEM/EDS) and micro-Raman spectroscopy were applied to the characterization of the phases in the ABs. Characterization of carbonaceous materials (CMs), observed in pristine asbestos phases in previous works, was therefore performed, addressing the micro-Raman laser beam on different points of the asbestos bodies, and Raman mappings on ABs were carried out for the first time. Coupling the data obtained by VP-SEM/EDS and micro-Raman spectroscopy, it was possible to collect information about the iron and carbonaceous phases adhered to the fibers, probably lost during the classical tissue digestion procedures. Information about both mineral and carbonaceous components might be useful to understand the whole structure of "asbestos bodies" and the inflammogenic and carcinogenic effects of the asbestos phases coupled to CMs, that might derive from cigarette smoke or from environmental pollution; this study might be useful to deepen also the possible detrimental role of ABs in the tissues. [ABSTRACT FROM AUTHOR]

Background Objectives Animals Methods Results Conclusions and Clinical Importance Respirable mineral particles can induce lower airway inflammation, but the role they play in asthma of horses is unknown.Respirable mineral particles, particularly respirable silica, are an overlooked determinant of chronic lung inflammation (asthma) in horses.Twenty‐three horses from an equine hospital population: 11 moderately affected (MEA), 7 severely asthmatic (SEA), and 5 control horses free from respiratory clinical signs.Prospective observational study. The quantity and quality of mineral particles found in bronchoalveolar lavage fluid (BALF) were characterized, with particular attention to silica content. Polarized light microscopy performed on cytospin slides identified intracellular birefringent particles as silica. Spectrometry‐based analysis performed on whole BALF determined total mineral and silica percentage and concentration. Group‐related differences in BALF mineral and silica load were investigated as well as associations with BALF cytology.Intracellular birefringent particles were increased in SEA vs MEA (median [interquartile range, IQR]), 12 [7] vs 4 [5] particles/30 high power fields [hpf], respectively; P = .01) and vs controls (4 [2] particles/30 hpf; P = .02). Total mineral concentration in BALF was similar between the groups studied, whereas silica concentration and percentage were increased in SEA vs MEA (1758 [887] particles/mL and 20 [10]% vs 867 [662] particles/mL and 8 [6]%; P = .009 and P = .001) and control group (355 [330] particles/mL and 6 [3]%; P = .0003 and P = .002). Silica load in BALF was associated with BALF neutrophilia in MEA and SEA.Respirable silica is associated with neutrophilic lower airway inflammation in horses and might contribute to asthma development. [ABSTRACT FROM AUTHOR]

Asbestos bodies (AB) were harvested from human lung tissue digests and isolated from uncoated asbestos fibers. Samples containing 1000 AB were added to a reactive solution to investigate the ability of AB to oxidize deoxy-D-ribose and generate reactive oxygen species (ROS) in the presence of ascorbate and hydrogen peroxide as determined by formation of thiobarbituric acid (TBA)-reactive products. Three types of asbestos fibers were tested for comparison, since they are known to be able to produce ROS. The absorbance values measured with 1000 AB were significantly higher than those observed with 1000 fibers of the three types of asbestos. Since in our reaction system the only source of transition metals was the iron-rich AB, data suggest iron derived from the ferritin coating of AB was involved in oxidant generation. Addition of iron to AB enhanced TBA-reactive product formation, while chelation of Fe with deferoxamine reduced this reaction. Hydroxyl radical scavengers 1,3-dimethyl-2-thiourea (DMTU) and mannitol (MN) also effectively blocked TBA-reactive product generation. Data indicate the importance of Fe in ABinduced oxidant damage. With the addition of polymorphonuclear leukocytes (PMN) to AB, incubation in the reactive solution gave very high amounts of TBA-reactive products, but using a reactive solution devoid of ascorbate, very low amounts of TBA-reactive products were generated. In the latter condition, the superoxide of cell membranes probably reduced and removed iron from AB-coating ferritin, but less effectively than ascorbate. Further after the possible reoxidation of Fe2+, Fe3+ could be coordinated by lactoferrin. Since such availability of reductant is never approached in living systems, the iron in the AB coating is unlikely to function as a catalyst of Fenton-type reactions in vivo. damage to DNA. However, under in vivo conditions, and macrophages are associated with AB. The leukocyte membranes contain lactoferrin, which is an iron chelator provide protection against radical-induced cellular damage al., 1988; Afeltra et al., 1997). of this study was (1) to determine whether AB in vitro released with consequent hydroxyl radical generation and toxicity and. [ABSTRACT FROM AUTHOR]

Examines the screening procedure of autopsy populations for previous occupational exposure to asbestos. Analysis of necropsy population for pleural plaques; Evaluation of optical count of lung asbestos bodies and uncoated mineral fibers; Autopsy screening in selecting cases related to occupational exposure.

Professional exposure to asbestos fibres is widely recognized as very dangerous to human health and for this reason many countries have banned their commercial uses. People, nevertheless, continue to be exposed to low dose of asbestos from natural and anthropogenic sources still in loco, for which the potential hazard is unknown. The aim of this research is to assess environmental exposure in an area with outcropping serpentinite rocks, which bear asbestos mineralizations, using sentinel animals which are a non-experimental animal model. We studied the burden of inorganic fibres in cattle lungs which come from two areas in Italy''s Western Alps bearing serpentinitic outcrops: Susa Valley with a heavy anthropization and Lanzo Valleys, with a minor human impact. The identification and quantification of inorganic fibres were performed by Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS). In comparison to humans, studies of animals have some advantages, such as no occupational exposure or history of smoking and, in the case of cattle, a sedentary life restricted to one region. Results spotlight that over than 35% of inorganic fibres found both in Susa and Lanzo valleys, belong to asbestos mineralogical species (asbestos tremolite/actinolite, chrysotile s.s., asbestos grunerite, crocidolite). We also observed a higher concentration of artificial fibrous products in Susa samples showing a correlation with the level of anthropization. These results confirm that sentinel animals are an excellent model to assess breathable environmental background because it is possible to eliminate some variables, such as unknown occupational exposure. [Copyright &y& Elsevier]

The diagnosis of asbestosis requires different criteria depending on whether it is in a clinical or medical/legal setting. In the latter context, only when a "diffuse interstitial fibrosis associated to asbestos bodies (ABs)" is present, it can be said to be asbestosis. Considering the medical/legal setting, the diagnosis must be certain and proven. Unfortunately, it is often difficult to identify ABs by light microscopy (LM), but this does not mean that the diagnosis should be clinically excluded. Other parameters are important, such as working history and/or diagnostic imaging. In addition to LM, normally used for diagnosis, there are other techniques, e.g.: scanning electron microscopy with attached microanalysis microprobe (SEM/EDS), but they require tissue digestion and higher cost. A new approach with micro-Raman spectroscopy and SEM/EDS techniques is able to analyse histological sections without other manipulations that could interfere with analysis of asbestos fibres. In this work, we propose an algorithm for asbestosis diagnosis, especially in the forensic medical field, demonstrating the importance of close collaboration between multiple professionals., (Copyright © 2024 Società Italiana di Anatomia Patologica e Citopatologia Diagnostica, Divisione Italiana della International Academy of Pathology.)

A revision of criteria for diagnosis of asbestos-related pathological conditions was performed studying specially asbestosis, pleural plaques and malignant mesothelioma, also taking into account the problems connected with histopathology. As regards the histological diagnosis of asbestosis, it requires the presence of diffuse interstitialfibrosis in a well inflated tissue remote from the site of a tumour or other large lesion, plus the presence of two or more asbestos bodies in a 1 cm2 section. As regards the imaging diagnosis, the HRTC 4-point scale proposed by Paris et al. (2004) has been adopted:--0 images not suggestive of interstitial pneumonia;--1 modest unilateral or bilateral interstitial abnormalities, involving restricted areas if bilateral;--2 interstitial abnormalities of limited extent, but consistent with a diagnosis of asbestosis, i.e. honeycombing, even without other parenchymal changes and even though unilateral, or else any two abnormal findings among thickened interlobular septa, intralobular lines or subpleural curved lines;--3 numerous bilateral changes on several slices involving more than 2/3 of the posterior third of each hemi thorax. Only points 2 and 3 were considered consistent with the diagnosis of lung fibrosis. Such HRCT findings are not specific for asbestosis, changes in the pleural wall such as diffuse plaques and thickenings contribute to the diagnosis of asbestosis. As regards the pleural plaques and asbestos bodies we remark that they are merely exposition markers. We also discussed the problems the pathologist may encounter in diagnosing mesothelioma; in this field the prospects are encouraging as microarray analysis are beginning to identify new molecular markers for mesothelioma.