Indicatori di pregressa esposizione ad amianto

Assessment of occupational and environmental asbestos exposure is based on measurement of airborne asbestos fibre concentration as for other pollutants. Unfortunately, there is a lack of data regarding many working sectors. Therefore, biomarkers of exposure can be often used effectively. In particular this is true in the health surveillance of asbestos-exposed workers that should take into account the intensity, latency and duration of exposure. In practice identification of asbestos bodies and fibres in the lung tissue is possible in case of surgical cancer resection or autopsy. Today in the diagnosis of asbestosis lung biopsy is almost never practiced, because most cases of asbestosis are asymptomatic disease diagnosed radiologically. Obviously, performing biopsy for study or legal purposes is not feasible. Mineralogical analysis of bronchoalveolar lavage fluid (BALF) represents a method of considerable utility for assessing asbestos exposure. This analysis includes the identification of asbestos bodies by light microscopy and asbestos fibres by scanning or transmission electron microscopy. A number of studies demonstrated that mineralogical analysis of BALF represents a reliable method for assessing asbestos exposure even after many years from the end of exposure. Its use in the diagnosis of asbestos-related diseases is generally accepted. The limits of the method is represented by the considerable interlaboratory variation that makes it difficult to compare the results obtained in different laboratories. For this reason, each laboratory should have its own reference values in order to compare the results with data obtained with the same technique in exposed populations and controls.