This study presents new morphological, mineralogical, and chemical data on fibrous erionite, a carcinogenic zeolite, discovered for the first time in the volcanic rocks of the Vulsini Volcanic District, Italy. The erionite fibers were investigated using OM, TGA, SEM-EDS, XRPD, and EDXRF techniques. They occur as inhalable aggregates composed of extremely thin, tangled crystals with very high aspect ratios, features that may enhance both inhalability and toxicological significance. Mineralogical associations with saponite indicate formation under low-temperature hydrothermal conditions (<150 °C), likely related to late- to post-magmatic fluid circulation through cavities and vesicles in the host volcanic rocks. Chemical analyses identify the zeolite as erionite-K, reflecting the potassic character of associated volcanic lithologies and highlighting the influence of host-rock and fluid chemistry on zeolite formation. Trace-element contents, particularly in As, V, Rb, and Pb, may represent an additional factor influencing fiber toxicity through synergistic effects. The occurrence of carcinogenic fibrous erionite in volcanic lithologies widely exploited for quarrying and industrial applications raises significant environmental and occupational health concerns for zeolitized volcanic terrains in central Italy. These findings highlight the need for detailed fiber characterization and mineralogical investigations to support exposure prevention and environmental risk assessment in future excavation and quarrying activities.
Mattioli et al. (Tue,) studied this question.