Characterization of asbestos minerals in serpentinites quarries in the Pollino Massif (southern Apennines, Italy)

In the Pollino Massif, in the southern Apennines, the asbestos minerals bearing serpentinites are widely exposed at several quarries (Pietrapica quarry, Timpa Castello quarry, Fagosa quarry and Ghiaia quarry), whose material was extracted and used as aggregates for construction, filling and embankments, and as ornamental stones. Airborne asbestos can be the result of extraction procedure as the stacking, storing and grinding of the serpentinites, so due to the environmental concerns the quarries have been abandoned. In the Pollino Massif serpentinites represent the lherzolitic to harzburgitic upper mantle basament of the Internal Liguride sequence of southern Apennines and can be classified as cataclastic and massive (Dichicco et al., 2015). Cataclastic serpentinites are fractured and deformed whereas those massive show a low fracturing and deformation. The serpentinites have homogeneous mineral compositions and are mainly composed by serpentine polimorphous, asbestiform tremolite, followed by actinolite, chlorite, magnetite and Cr-spinels, and subordinatly calcite, dolomite, and clay minerals. Further, edenite, currently not regulated by the Directive 2003/18/EC of the European Parliament and of the European Council of 27th March 2003, has been recently also detected for the first time (Dichicco et al., 2019). Serpentinite rocks can release significant amounts of fibers of hazardous minerals for the human health, into the air, water and soil, either through geogenic weathering processes or human activity. The observed fibers in the outcrops are of two types: 1) large and elongated fibers that occupy the entire surface of the rock; 2) tiny fibers forming a network throughout the rock. The aim of this work is to characterize in a detailed way the asbestos minerals of representative serpentinite samples taken from the four quarries using the combination of different analytical techniques: field surveys, X-Ray powder diffraction (XRPD), scanning electron microscopy combined with energy dispersive spectrometry (SEM/EDS), µ-Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR) in order to assess the impact on the environment and public health.