Particulate Matter And Black Carbon Concentration Levels In Ashaiman, A Semi-Urban Area

Abstract

Using IVL PM2.5 and PM10 particle samplers, airborne particulate matter was sampled from Ashaiman, 30 km from Accra-capital of Ghana. The airborne particles were collected on Teflon filters for a period of three months. In addition to determination of particulate mass in the two fractions by gravimetrical method, aerosol filters were analyzed to determine black carbon (BC) concentration levels using the black smoke method. BC fractions in fine and coarse, together with PM2.5 to PM10 ratio were determined. PM2.5 mass concentrations determined averaged 23.26 ugm-3 (3.85 - 46.43 ~gm-3 ) and that of PM10 was 96.56 ~gm-3 (37.10-293.06 ~gm-3 ). The results were compared with some literature values and World Health Organisation guideline values. The values obtained for PM2.5 to PM10 ratio and for PM10-2.5 concentrations, suggest that. the semi-urban background aerosol is not only largely made up of combustion generated carbonaceous particles but also particulate matter emissions from natural activities.