Quality based critical review (QBCR) of the epidemiological literature on silica, silicosis, tobacco smoking and cancer

This report is the final version of the summary of quality rated epidemiological studies about silica and lung cancer.

Abstract: The potential relationship between silica, silicosis and lung cancer was examined in many epidemiological studies. Interpretation of study results is often difficult due to insufficient assessment of exposure and potential confounders (especially tobacco smoking) as well as other deficiencies in methods. The present publication summarizes the relevant epidemiological studies selected based on specific quality criteria. The analysis of these studies considers the quality of exposure data, possible confounders and the influence of the status of silicosis and smoking. Overall, these studies of relatively high quality demonstrate an increased risk for lung cancer among occupational groups with high crystalline silica exposure, accounting for the potential influence on the risk estimates of silicosis and tobacco smoking. However, due to the lack of reliable data on crystalline silica exposure in any of the available studies, recommendations for a health-based exposure limit value are not possible at this time.