Pneumoconiosis in Georgia kaolin workers.

Middle Georgia kaolin workers (n = 459) were surveyed for the presence of pneumoconiosis by chest radiograph and for respiratory symptoms by questionnaire. Pulmonary function was measured in all workers by spirometry. The overall prevalence of pneumoconiosis in this population was 9.2%. Multivariate analysis demonstrated that the only significant correlates with the radiographic presence of pneumoconiosis were ages greater than 55 yr and greater than 15 yr work exposure in the job category associated with greatest dust exposure. There was no correlation between the radiographic presence of pneumoconiosis and respiratory symptoms, cigarette smoking, or history of tuberculosis. Except in cases of complicated pneumoconiosis (large opacities), spirograms of workers with radiographic evidence of pneumoconiosis were not significantly different from spirograms of workers with normal radiographs. Clinical impairment of pulmonary function does not occur except in advanced cases, and appears to be mild even in these.