ASSESSMENT OF AMBIENT AIR QUALITY IN HARAR CITY, ETHIOPIA

Abstract

Air pollution is responsible for an estimated 7 million deaths across the globe due to fossil fuel burning, vehicular emissions, factories, industries and other activities. Despite vulnerability of communities living in close proximity to major roadways and factories, no scientific studies explored the ambient air quality of Harar city. The objective of this study was to assess the concentration levels of particulate matters (PM2.5 and PM10) Carbon monoxide (CO), Sulphur dioxide (SO2), and Nitrogen dioxide (NO2), and compare them against both Ethiopian and World Health Organization (WHO) guidelines to determine exceedance levels and spatial distribution of the pollutants in the Harar city. Measurements were taken across various sample points within the city, providing a comprehensive overview of spatial distribution and pollutant concentrations. A total of 21 air samples at each of 16 junctions for each parameter for 7 days using Aeroqual’s Series 500 handheld portable device. Moreover, maps of the selected criteria air pollutants were created and visualized to represent the spatial distributions of the pollutants in Harar City. Data analysis revealed that the average concentrations of PM2.5, PM10, CO, SO2, and NO2 were 79.77µg/m³, 185.33 µg/m³, 2586.51 µg/m³, 47.42 µg/m³, and 216.49 µg/m³, respectively. Among these values, PM2.5, PM10 and NO2 significantly exceeded both WHO and Ethiopian air quality guidelines. Carbon monoxide and SO2 also showed high exceedance levels from WHO guidelines indicating a critical issue with air quality in Harar City even though they were within the national guidelines. This study indicates the urgent need for effective mitigation strategies to improve air quality and protect public health in Harar. Thus, better urban planning, promoting the use of cleaner energy sources, and implementing stringent emissions regulations for both industrial and vehicular sources could improve ambient air quality of the city.