Assessment of brick kiln’s air pollutants impact on human health in industrial areas of Kathmandu Valley, Nepal

Abstract

This cross-sectional study investigates the health impact of air pollutants from brick kilns in the Kathmandu Valley, Nepal's most urbanized region. A mixed-methods approach was used, combining quantitative and qualitative data. Air quality data was collected from working environment, exposed and control households using devices (Air Visual Pro, calibrated with GRIMM sensors and Gas meter).

PM_2.5 concentration around brick kilns was 151.2 μg/m³ compared to control grocery stores (8.8 μg/m³), while households to the brick kilns (<1 km) was 84.6 μg/m³ compared to control households (>1 km) 7.5 μg/m³. The correlation between PM_2.5 and self-reported respiratory symptoms was greater in the exposed communities compared to control one with a strong positive correlation for breathlessness (Pearson correlation coefficient r = 0.68, p < 0.05), moderate correlation for persistent cough (r = 0.53, p < 0.05), asthmatic symptoms (r = 0.55, p < 0.05), phlegm (r = 0.58, p < 0.05), wheeze (r = 0.44, p < 0.05) and bronchitis (r = 0.41, p < 0.05). Around brick kiln workers, PM_2.5 concentrations showed a strong correlation with breathlessness (r = 0.56, p < 0.05), phlegm (r = 0.70, p < 0.05), and wheeze (r = 0.82, p < 0.05), and weak correlation with persistent cough (r = 0.18, p > 0.05) and asthmatic symptoms (r = 0.24, p > 0.05). The findings suggest high PM_2.5 concentrations at brick kiln sites are associated with respiratory symptoms among residents living in local communities. This study emphasizes better quality management through various interventions.