An old threat in a new setting: High prevalence of silicosis among jewelry workers.

BACKGROUND: Silicosis is caused by inhaling free crystalline silica. Few case reports have addressed the risk of silicosis in the jewelry trade where chalk molds containing a high percentage of silica are used in gold and silver casting. We conducted a cross-sectional study involving 100 goldsmiths exposed to silica. METHODS: All workers replied to a respiratory questionnaire and underwent a full clinical examination, pulmonary function tests wit a study of flow, volumes and diffusion capacity, a chest X-ray and a high-resolution CT scan. RESULTS: High-resolution CT scan visualized signs of silicosis in 23 workers involved in gold and silver casting, confirmed by standard chest X-rays in 10 cases. In the 23 workers with CT evidence of silicosis Total Lung Capacity, FEV1 and the Lung Diffusing Capacity did not differ from the workers without the disease. Pulmonary function tests, including diffusing capacity did not correlate with silica exposure, measured as refractory material used to make the molds. CONCLUSION: In this study we demonstrate that use of chalk molds in casting in jewelry causes high prevalence of silicosis. Lung function test were not able to discriminate between workers with and without silicosis. The composition of the dust could be responsible of the high prevalence observed.