Fluoro-Edenite from Biancavilla (Sicily, Italy): A Comprehensive Review and New Perspectives on a Fibrous Amphibole of Geological and Health Concern

The present review paper focuses on the peculiar environmental and health implications of fibrous amphibole “fluoro-edenite”, a new mineral first reported in Biancavilla (Etna Mount, Sicily, Italy). Its presence has been linked to an unusually high incidence of malignant pleural mesothelioma, as seen from national surveys during 1988–1997, marking the first case study of natural occurrence of fibrous amphibole in a volcanic context. Despite remediation efforts since the cessation of quarrying activities at the “Il Calvario” quarry, the risk of fiber exposure may extend beyond urban areas to surrounding soils and volcanic formation, not fully characterized yet. This review synthesizes relevant existing literature on mineralogical and chemical features of fluoro-edenite, while also enriching current understanding with new observations from optical microscopy, stereomicroscopy, and Scanning Electron Microscopy (SEM). Our analyses reveal the presence of fluoro-edenite amphibole not only in the altered samples but, significantly, within the massive rock samples. This finding expands its known distribution and offers initial consideration on public health implications related to massive lava rock, which crops out. This study highlights the importance of ongoing monitoring, detailed geological surveys, and further research into fiber occurrences and distribution in the volcanic systems, of which Mt. Etna represents the first case of natural occurrences, in order to fully assess their impact on public health.