Pneumoconiosis in chromite miners in South Africa.

Ten chromite miners in South Africa have been found to show radiological evidence of a fine nodulation; five of these miners had worked only in chromite mines. These cases occurred in a labour force of some 1,500 persons subjected to regular examination. Clinical evidence and the results of intratracheal injection of chromite suspension into rats indicate that the radiological changes are due not to fibrosis but to a benign deposition of chromite (CrOFeO) dust in the lungs.