Inter-Laboratory Study for the Asbestos Detection in Bulk Materials: First Italian Scheme

Italian Health Ministry established by regulation the minimum requirements for laboratories intending to perform asbestos analysis and the organization of a quality control scheme to which the laboratories must refer. Three proficiency testing schemes for asbestos detection in bulk materials using polarized light microscopy (PLM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) were developed according to the regulation of Health Ministry. The schemes were organized in rounds. In each round the laboratory received one batch of 4 samples. The participant laboratories were 475. The performance of laboratory as satisfactory, unsatisfactory or awaiting classification. The samples of the rounds were real world materials from abatement project and might contain any of the asbestos types. Ceiling-tile containing vitreous fibers caused the highest frequency of false positive; 87% of errors incurred in FTIR and 60% in XRD. Vinyl-floor tiles caused most false negative; 100% of errors incurred in PLM in the second pilot program, 13% in FTIR and 10% in XRD. One of the main factors causing variability of results turned out to be related to the skill of the analysts. Training and experience of the analysts help to get a reliable and reproducible asbestos analysis.