Portable Raman Spectrometer for In Situ Analysis of Asbestos and Fibrous Minerals

Abstract

Asbestos inhalation is associated with fatal respiratory diseases and raises concerns from the perspective of workplace safety and environmental impacts. Asbestos and asbestos-like minerals naturally occur in rocks and may become airborne when outcrops or soils are disturbed by anthropic activities. In situ detection of these minerals is a crucial step for the risk evaluation of natural sites. We assess here whether a portable Raman spectrometer (pRS) may be used in the identification of asbestos and asbestos-like minerals at the mining front during exploitation. pRS performance was tested at three geologically different mining sites in Italy and New Caledonia and compared with a high-resolution micro-Raman spectrometer (HRS). About 80% of the overall in situ analyses at the mining front were successfully identified by pRS, even when intermixed phases or strongly disaggregated and altered samples were analyzed. Chrysotile and tremolite asbestos, asbestos-like antigorite, and balangeroite were correctly detected during surveys. The major difficulties faced during in situ pRS measurements were fluorescence emission and focussing the laser beam on non-cohesive bundles of fibers. pRS is adequate for discriminating asbestos and asbestos-like minerals in situ. pRS may support risk assessment of mining sites to better protect workers and environment.

Identification of iron compounds in chrysotile from the Balangero mine (Turin, Italy) by micro‐Raman spectroscopy

“…The distinctive OH stretching bands with its strongest peak at 3569 cm −1 and other contributions at 3508, 3619, 3644, and 3717 cm −1 confirmed the discrimination of balangeroite among the other fibrous phases. [ 26,57 ] Weak features from chrysotile fibers are generally detected together with those of balangeroite, due to their similar structure (as marked with the symbol * in Figure 3a,b). In balangeroite, the presence of Fe as a constitutive element is confirmed by the EDS spectrum (Figure S2).…”

Synthesis and characterization of chrysotile/erythrosine composite to detect asbestos

“…A portable Raman spectrometer for the in situ analysis of asbestos was also reported. 10) Our recent study demonstrated that dyeing the surface of building waste materials with an aqueous solution of inexpensive and safe methylene blue and then dyeing it with an aqueous solution of red no. 3 (erythrosine), which is commercially available as a low-cost food coloring, chrysotile becomes stained by erythrosine.…”