Chronic obstructive pulmonary diseases; Coal dust; Lung cancer; Silica

While working underground, miners are exposed to a number of risk factors that have a negative impact on their health and may be a cause of an increased mortality in miners. The aim of the study was to compare total and specific mortality in black coal miners with acknowledged coal-workers? pneumoconiosis (CWP) and without CWP, and the mortality of the general male population in the Czech Republic in the period 1992?2013. The sample consisted of 3476 coal miners with CWP and 6687 ex-coal miners without CWP, who were removed after achieving the maximum permissible exposure (MPE). The mortality risk differences were analyzed with the use of the standardized mortality ratio (SMR) and 95% confidence interval. Significantly higher total mortality (SMR = 1.10; 95% CI: 1.02?1.17), and mortality from malignant neoplasm (SMR = 1.16; 95% CI: 1.03?1.30), lung cancers (SMR = 1.70; 95% CI: 1.41?2.04), and non-malignant respiratory diseases (SMR = 2.78; 95% CI: 2.32?3.31) were found in the sample of coal miners with CWP. In this sample, the severity of CWP was assessed, and the SMR increased with the severity of CWP. The total (SMR = 0.86; 95% CI: 0.82?0.91) and specific mortality of miners without CWP were not higher compared with the general population. In the case where the miners were removed from underground work after achieving the MPE (without CWP), their mortality was not higher than that of the general population, but the mortality of miners with CWP was higher compared to the general population. This mortality was affected by malignant and non-malignant respiratory diseases.