Occupational monitoring and health risks assessment of respiratory exposure to dust in an industrial unit of producing China Clay

Introduction: The respiratory system, as one of the most important organs of the human body is affected by adverse health effects and consequences of particulate matter. The main purpose of recent study was to determine the occupational exposure to workers to crystalline silica and inhalable dust and determine its health risks. Methods: In this analytical cross-sectional study, sampling was performed in an industrial unit producing China Clay based on standard methods and individual and environmental sampling methods. Then the obtained data analyzed by SPSS software version 22 .The risk assessment of occupational exposure of workers to crystalline silica was carried out based on the proposed EPA procedure. Results: The average exposure of workers to inhalable dust and crystalline silica was measured 4.46±1.34 mg/m3 and 0.57±0.10 mg/m3, respectively. The mean environmental concentration of the inhalable particles was 6177.71 µg/m3 (range: 4088.30- 8289.70 µg/m3). In all occupational groups the risk of cancer was obtained less than 10-6. Hazard quotient (HQ) values ​​for operator one (5.34) and two (4.79) crusher machine, crusher machine loading operator (8.49), dryer operator (1.91), slurry operator (3.01) and filter press operator (1.78) was more than permissible limit. Conclusion: The average concentration of inhalable dust and crystalline silica was more than permissible limit in this industry. According to the results of the risk assessment, the priority of serious control actions is necessary to reduce the risk of non-cancerous complications in the crushing, drilling, slurry and filter press occupational groups.