Assessing the Association between Occupational Particulate Matter (PM2.5) Exposure from Charcoal Production and Lung Function Decline in Malawian Adult Workers: A Cross-Sectional Study in Mchinji District

Charcoal production is a major economic activity in Malawi and a source of high occupational particulate matter (PM2.5) exposure. The specific impact of this exposure on the respiratory health of Malawian charcoal workers remains inadequately documented. This study aimed to determine the association between occupational PM2.5 exposure from charcoal production and lung function decline among adult workers in Mchinji District, Malawi. A cross-sectional study was conducted with adult charcoal workers. Personal PM2.5 exposure was monitored using portable samplers. Lung function was assessed via spirometry, measuring forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Questionnaires collected data on demographics and work history. Linear regression models analysed the association between PM2.5 exposure and lung function parameters. Workers were exposed to a mean PM2.5 concentration of 287 µg/m³. A significant inverse association was found between PM2.5 exposure and lung function. For every 50 µg/m³ increase in PM2.5 exposure, FEV1 declined by an average of 42 mL. Workers in the highest exposure quartile had 3.2 times higher odds of a restrictive lung pattern compared to the lowest quartile. Occupational exposure to PM2.5 from charcoal production is associated with a measurable decline in lung function among these workers, indicating a substantial occupational health risk. Implementation of occupational exposure control measures, such as improved ventilation and personal protective equipment, is required. Regular health surveillance, including spirometry for at-risk workers, should be established. Policy interventions to promote safer production technologies are also recommended. Occupational exposure, particulate matter, PM2.5, charcoal production, lung function, spirometry, Malawi, cross-sectional study. This study provides quantitative evidence on the association between occupational PM2.5 exposure from charcoal production and lung function decline in a Malawian context, filling a critical gap in local occupational health data.