[Pulmonary silicosis (not including asbestosis and berylliosis]

The pleuro-pulmonary pathology of asbestos, top most of silicates, is today well known. Other silicates, talcum powder, clays, micas essentially, are exploited and commercialized. Their pathology is less well known and often contradictory because of the heterogeneity of the inhaled minerals. All can contain large quantities of quartz and some varieties of talcum and a considerable proportion of asbestos fibres. These minerals can provoke severe pneumoconioses, silicoses and asbestoses respectively. Some relatively pure products do not contain these contaminants. In case of intense and prolonged dust inhaling, they can produced an impressive pneumoconiosis with relatively mild clinical signs as shown by the series of 27 cases of pneumoconiosis from the french talcum powder as reported by the authors. The chemical nature and electronic structure of different silicates are very similar. It raises the question of the noxious effect of asbestos and the relative innocuousness of other minerals of the same family, and wether the fibrous structure alone is implicated.