The health effects of anthracite surface coal mine dust on miners were investigated. Medical examinations were offered to 1348 workers actively employed at 31 mines in the anthracite coal region of northeastern Pennsylvania; 1073 workers participated. A postero/anterior chest radiograph was taken and a spirometry test performed. Workers were divided into two main categories depending on whether or not they were exposed to dust in another job as well as working at the mines. Subsequent to these two divisions, each group was subdivided according to the work done at the mine: drilling, coal cleaning, or other jobs. The examinations indicated an increased prevalence of radiographic small rounded opacities in drillers, suggesting that the quartz (14808607) exposures at the drilling operations may have been excessive. Decreases in forced expiratory volume in 1 second, forced vital capacity, and peak flow were also significantly related to tenure at drilling operations after adjustments had been made in the data for age, smoking habits, and exposures in dusty jobs other than coal mining. No significant relationships were found for coal cleaning operations and either radiographic or spirometric test results. The authors recommend that further work should be done to determine whether average quartz exposures at anthracite surface coal mine drilling operations are within occupationally allowable standards, and to devise ways in which this dust exposure can be better controlled.