Prevalence of and risk factors for obstructive pulmonary dysfunction caused by coal dust exposure: A cross-sectional study

Abstract

Abstract Background: Although previous studies have shown that coal dust exposure can lead to decreased lung function, little is known regarding the prevalence of and risk factors for obstructive pulmonary dysfunction (OPD) in Chinese coal workers. The present study investigated the prevalence of and risk factors for OPD in Chinese coal workers. Methods: Health monitoring data were collected from 3534 workers in 8 different state-owned coal mines from January 1, 2021, to June 30, 2022. Ultimately, data from 3450 workers were eligible for analysis. OPD was defined as FEV1/FVC less than 70%. FVC dicline was defined as FVC/Pre less than 80%. High-intensity exposure refers to underground workers who basically work underground all day; correspondingly, low-intensity exposure refers to workers who only work underground for part of the day. Logistic regression analyses were used to analyze the relationships between clinical variables and OPD. The attributable risk percentage for each risk factor was calculated as follows: (（OR-1）/OR)x100%. Results: The overall prevalence of OPD was 2.6%, and the prevalence of FVC decline (FVC/Pre<80%) was 21.8%. The prevalence of OPD was higher in the high-intensity exposure group than in the low-intensity exposure group , higher in the smoking group than in the no smoking group, and higher among workers aged 50 years or older than among those under the age of 50. Risk factors for OPD included age greater than 50 years old, high-intensity exposure, duration of exposure more than 20 years, smoking, and dust concentration exceeding 2 mg/m3. High-intensity exposures were considered to contribute approximately equally to the prevalence of OPD as smoking. Conclusion: Coal dust exposure can lead to OPD. High-intensity exposure, a duration of exposure of more than 20 years, smoking, and dust concentrations exceeding 2 mg/m3 are major risk factors for OPD. Cigarette smoking and coal dust exposure are major preventable risk factors for the disease. Enhancing occupational protection, strengthening smoking control in underground workplaces and regular monitoring of lung function for early detection of abnormal lung function are important for protecting workers' health.