Silicosis in Dutch construction workers

Introduction: Construction workers exposed to crystalline silica are at risk for developing silicosis, lung cancer and COPD. Since no therapy for silicosis is available, early detection is needed to avoid further progression of the disease by reducing exposure. In collaboration with the Dutch employers and employees organisation for occupational health and safety in the construction industry (Arbouw) a health surveillance programme was implemented. Objective: to identify silicosis in silica exposed construction workers. Methods: a diagnostic model predicting the probability of silicosis was used as a medical triage system based on risk stratification 1 . Construction workers with a high risk (sumscore ≥ 5) were invited for medical evaluation, including a low-dose high resolution CT-scan of the lungs (HRCT) and spirometry. HRCT was used as the reference standard for silicosis. Results: Of > 75.000 construction workers 1123 (1,5%) were at high risk according to the prediction rule, of whom 295 (response 26%) underwent a clinical investigation. Mean age was 50 (± 6) yrs, number of pack years 26 (± 16). FEV 1 was 96 (±16) %pred., FEV 1 /VC 72 (± 6)%. Silicosis was found in 64 workers (22%), 37 (13%) of which in an early stage, corresponding well with the model. HRCT showed numerous other abnormalities including different interstitial patterns, pleural thickening, emphysema and coronary artery calcifications. COPD was present in 62 (21%) workers. Conclusion: silicosis seems still common among silica exposed construction workers, together with co-existing comorbidities. References 1. Suarthana E, Moons KG, Heederik D, Meijer E. A simple diagnostic model for ruling out pneumoconiosis among construction workers. Occup Environ Med. 2007; 64:595-601.