On the question of the pathogenetic importance of cobalt for hard metal fibrosis of the lung

Pulmonary fibrosis in hard metal grinders has been observed to an increasing degree in recent years. Most authors attribute the cause of this disease to the influence of the cobalt contained in hard metals. The present case dealt with a 36-year-old man who had been exposed to the grinding dust from sintered hard metal parts for more than 10 years. Biopsy of the lung revealed an advanced, active pulmonary fibrosis. In the biopsy specimens cobalt was determined by flameless atomic absorption. The cobalt content in the biological specimens of the patient (urine: 7.5 µg/l; lung: 1010 µg/kg wet weight) was significantly increased compared with the values measured in normal controls.