52 research outputs found

    Fibrous mineral detection in natural soil and risk mitigation (1(st) paper)

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    The paper describes a fibrous mineral detection methodology, which is based on the use of alternating rotary motion sieving equipment. The equipment was redesigned to meet additional requirements with respect to initial ones. Under this methodology, the fine fraction passing through the sieves was recovered and analysed to determine the sedimentology, mineralogy and morphology of the potentially particulating fraction. Reliance was made on the following analytical techniques: laser granulometry, scanning electron microscopy/energy dispersive spectrometry (SEM/EDS) and polarised and phase contrast light microscopy (PLM, PCLM) for fibrous mineral identification and Walton-Beckett / whole field fibre counting. The samples for the analyses came from known areas with fibrous minerals, e.g. Lauria (Basilicata), and less known areas, e.g. the Natural Reserve of Mt. Rufeno (Latium) and Biancavilla (Sicily). With this methodology, fibres may be directly detected in both farmed and unfarmed soil with fibrous minerals and the process may be repeated in the various stages of farming or during works for creation of fire barriers or lanes, hydrogeological restoration etc. The goal is to identify risks arising from the natural occurrence of asbestos upon atypical activities, such as farming and forestry. With regard to exposure, consideration was given to fibrous minerals not currently classified in the relevant legislation, thus going beyond the search for asbestiform minerals in quarry sites located in ophiolite outcrop areas

    Fluoro-edenitic fibres in the sputum of subjects from Biancavilla (Sicily): a pilot study

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    BACKGROUND: An excess of mortality for malignant neoplasms of the pleura in Biancavilla, promoted an investigation for pleural mesothelioma, disclosing 17 cases. As the absence of known sources of asbestos exposure, a local stone quarry, located near the inhabited area, used for the extraction of building materials, was investigated. Amphibolic fibres were found in the quarry and identified as fluoro-edenite "new end-member of the edenite / fluoro-edenite series" and recognized as the fluoro-edenite holotype by International Mineralogical Association – Commission on New Minerals and Mineral Names. A pilot study was performed to verify the feasibility of using spontaneous sputum as an exposure indicator for these fibres, in a context in which the use of aerosol-induced sputum technique would not be easily accepted. METHODS: Hypothesizing a behaviour of the new fibre analogous to that of asbestos, the determination of the free fibres and the ferruginous bodies in spontaneous sputum was carried out. Phase Contrast Optical Microscope and an Environmental Scanning Electron Microscope fitted with X-ray energy dispersive analysis system (micro-analysis) were used to examine the samples. The criteria for inclusion in the study were: 1) subjects hospitalized for exacerbation of chronic obstructive pulmonary disease symptoms, 2) age ≥ 45 years, 3) residence in Biancavilla for at least 30 years. RESULTS: The preliminary findings are related to 12 subjects (7 females and 5 males). Uncoated fibres (with length > 5 μm, diameter < 3 μm, aspect ratio 3.1) and ferruginous bodies were searched. Six out of twelve subjects (4 females, 2 males) had at least one of the three samples positive for the presence of fluoro-edenite, confirmed by micro-analysis. The fibre concentration found in the sputum ranged from 0.04 to 10 fibres/g; the length from 20 to 40 μm, the diameter was < 0.5 μm. No ferruginous bodies were found in any of the samples. The four women with a positive sample were housewives. Of the two men with a positive sample, one was a farmer and the other a mason. Therefore, it may be assumed that the exposure to fluoro-edenitic fibres was mainly environmental. CONCLUSION: The occurrence of the pleural mesothelioma cases and the presence of fluoro-edenitic fibres in spontaneous sputum, evidence the need to study the biological activity of fluoro-edenitic fibres and the implementation of epidemiological monitoring systems

    K-FELDSPARS AS VOLCANIC PALEOSOIL INDICATORS - FIRST INVESTIGATION IN THE ALBAN HILLS VOLCANIC AREA, LATIUM, ITALY

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    A detailed mineralogical study was carried out on potassium feldspars contained in some ''paleosoil'' samples from the Alban Hills volcanic region (Latium, Italy). Chemical and structural correlation of the data allowed a comparison with data on sanidinite feldspars from the same area and with data on other nearby volcanic complexes. The chemistry (N-Or = 72.6 divided by 88.3 % Or) and lattice parameters [a(o) = 8.492 divided by 8.574(Angstrom), b(o) = 12.996 divided by 13.034(Angstrom), c(o) = 7.163 divided by 7.190(Angstrom)] indicate a prevalently more sanidinitic character for the paleosoil feldspars compared with those in Alban ''sanidinites''. The particular structural state (HT disorder) of some paleosoil K-feldspars would suggest different crystallization temperatures and, for some samples, also a possible pressure influence during their formation. The abundance of K-feldspars in the samples examined and their less orthoclasic features compared with feldspars found in sanidinitic Alban ejecta would highlight a rather different genetic process for these paleosoils compared with that of the more typical Alban volcanic products, mainly of leucititic composition. The studied K-feldspars may be considered as good volcanic paleosoil indicators and a probable allochthonous origin of the Alban paleosoils is hypothesized

    The sodalite group minerals in the volcanic areas of Latium

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