Mineralogical analysis of bronchoalveolar lavage in talc pneumoconiosis

Bronchoalveolar lavage (BAL) fluid obtained from six talc workers with pneumoconiosis was studied by optical and electron microscopy for its mineral content. Two of these workers were mainly exposed to American and Australian talc, and the other four were exposed to French talc (Luzenac). In all lavage fluids, talc particles and talc bodies were abundant, sometimes many years after the end of exposure. A qualitative difference was the presence of tremolite asbestos fibres in the two patients exposed to American and Australian talc and its absence in the four French talc workers. The presence of tremolite in lavage is attributed to a geological association of this mineral with the inhaled talc. On the other hand, chlorite was abundant in BAL of the French talc workers. Hence, we suggest that bronchoalveolar lavage can confirm exposure to talc and provide information about the heterogeneity of inhaled dust.