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Published on: May 13, 2020
Pneumoconiosis in a vermiculite end-product user
1Brevard VA Clinic, Viera, Florida 32940, USA. Thomas.Howard@Med.VA.Gov
Background:
Vermiculite is a silicate used as an insulating agent, soil additive, and carrier for chemicals and fertilizers. It is currently perceived to have no adverse effects to "end-product" users. An 82-year-old man presented with complaints of progressive dyspnea on exertion.
Methods:
A clinical evaluation included a chest radiograph, complete pulmonary function testing, CT scan of the thorax, and comprehensive occupational and environmental history.
Results:
The patient had clinical and radiographic features of advanced pulmonary interstitial fibrosis. The presence of calcified pleural plaques, together with the other clinical and radiographic features, strongly supported a diagnosis of asbestosis. His only significant exposure was to vermiculite used in the workplace for several hours per day from 1970 to 1987.
Conclusions:
This case represents the first report of an end-product vermiculite-user with probable asbestosis, and together with recent similar findings in a vermiculite expansion plant worker, requires further epidemiologic investigations.
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