Computed tomography of the thorax in workers exposed to hard metals.

Hard metal disease is an occupational lung disorder occurring primarily among workers employed in the cemented tungsten carbide industry."4 Interstitial pulmonary fibrosis, acute obstructive pulmonary disease (asthma), and dermatitis are the main clinical manifestations of such exposure. The workers in this industry are at risk from exposure to powders of a variety of hard metals during the manufacture of tools. These metals include tungsten, titanium, tantalum, vanadium, niobium, and cobalt.'" They provide the hardness, strength, and heat resistance required in tools. Many are inert and harmless but cobalt is believed to be a causative agent of pulmonary disease. We performed thoracic computed tomography (CT) scans on 1 1 hard metal workers and describe the findings here.