ESPOSIZIONE AMBIENTALE A FIBRE INORGANICHE NATURALI E ARTIFICIALI IN UNGULATI VISSUTI NEL PARCO REGIONALE DE ¿LA MANDRIA¿

It has long been established that occupational exposure (high dose) certain fibrous minerals is harmful to human health. The effects of environmental exposure (low doses) is still rather difficult to determine. The aim of the thesis is to assess whether sentinel animal systems (SSA) may be considered a useful tool for assessing the effects of continuous, low dose, to airborne fibrous minerals in the environment (natural environmental exposure), without the effect of professional exposure and / or confounding factors (eg. the habit of smoking). For this purpose were recovered and examined samples of lung tissue of 15 ungulates lived in the Regional Park of "La Mandria", located at the entrance of the Valli di Lanzo, in the province of Turin. The investigations were carried out by using the scanning electron microscope (SEM) with attached energy dispersive spectrometer (EDS) and have allowed us to obtain qualitative and quantitative data on mineral fibers breathe and in particular on asbestosis. The area examined is particularly suitable for the study of environmental exposure to asbestos fibers because some guys are content is naturally present in rocks, and in the resulting material from the former mine Balangero, used to line the paths of Park "La Mandria". The fibers found in the lungs of ungulates are chemically related to 2 main groups: silicate fibers and non-silicate fibers. Here are, in descending order of abundance was found, the different types of silicate fibers found: artificial silicate with Na and possibly Mg, Al, Ca, K, chrysotile / antigorite; illite / smectite / montmorillonite, hornblende, tremolite asbestos, mica, phyllosilicates unidentified, vermiculite, crocidolite, Na-Ca feldspar, chlorite, Edenite, pyrophyllite, kaolinite, diopside, zeolite. The non-silicate fibers are found on two different types, listed below in descending order of abundance was found: titanium dioxide, gypsum or anhydrite. Both crocidolite and tremolite asbestos fibers and chrysotile/ antigorite fibres were found in 40% of the samples. Globally, these three groups were present in 47% of the samples. The chrysotile / antigorite fibres originate from both serpentinite rocks (natural source) and from the resulting material from the former mine Balangero (natural source), while those of chrysotile can come from these rocks (natural source) and materials containing asbestos ( anthropogenic sources) such as the roofs of buildings. The fibers of tremolite asbestos come from serpentinite rocks (natural source) and not the material is ex-mine ore Balangero because this species does not appear to be present in the rocks of that area. Crocidolite fibers come exclusively from the asbestos-containing materials (anthropogenic source, such as the roofs of buildings) because this type of asbestos isn't naturally present in Italian territory. Although it is not possible to establish which of the two sources (natural and anthropogenic) come chrysotile fibers / antigorite, the SSA represent a good model for assessing environmental exposure in relation to topographic features, geological and human environment in which they lived.