Three cases of respiratory disease in workers with occupational exposure to talc containing asbestos fibers are reported. Standard chest roentgenographs, high-resolution computed tomography, respiratory function tests, morphologic study of bronchoalveolar lavage fluid (BAL), light microscopic examination, and mineralogical analysis by transmission electron microscopy (TEM) of BAL was performed. All subjects showed bilateral pleural plaques, and in two subjects the study of BAL revealed lymphocytic alveolitis with an increased T4/T8 ratio. Mineralogical analysis of BAL detected asbestos-fiber concentrations of 510, 2039, and 3392 fibers/mL and many asbestos bodies. In one patient, mineralogical analysis of lung tissue was also performed; a concentration of 3,659,000 fibers/g dry tissue was found. Simultaneously, we performed a mineralogical study of 12 commercial talc samples, including those used by the patients during the last phase of their working lives. TEM revealed asbestos fibers in five samples. Two subjects used two of these talc powders. The study presented here confirms the need to perform all relevant clinical tests together with the study of BAL and mineralogical analysis of the materials to which the patients are or were exposed to determine occupational exposure to fibers, including those associated with talc, which are often misidentified.
From the Institute of Occupational Medicine, University of Siena, Italy.
Address correspondence to: Giuseppina Scancarello, MSc, Istituto di Medicina del Lavoro, Via dei Tufi, 1, 53100 Siena, Italy.