[New data on pumice's structure and biological effects among miners and millers]

Pleural plaques among pumice workers on Lipari Island have been described and the Authors have suggested the hypothesis that such biological effect could be related to the particles' morphology characterized by the presence of elements similar to fibers. Analysis on compact bulk materials and on dust samples from different sites of the Island have been performed to obtain information on the chemical composition of such materials. The Scan Electron Microscopy (SEM) analyses confirm the presence of fibrous particles with a chemical structure similar to the Refractory Ceramic Fibers (RCF) composition. These results could explain the presence of plural plaques among the workers and new clinical and epidemiological evaluations of the potential effects associated to this exposure are needed.