PARTICULATE CONCENTRATION AROUND BUSY TRAFFIC LOCATIONS IN OGBOMOSO, NIGERIA

This research work reported the results of the investigation of air pollution from automobiles and other anthropogenic sources at intersections of ten (10) selected busy junctions in Ogbomoso, South-western, Nigeria. Ten (10) sampling sites were considered with the sampler, aerosol mass monitor (831) placed 1-1.5m above the ground level and 1m away from the edge of the road. Particulate matter less than 1.0, 2.5, 4.0, and 10µm were monitored in rush hour (RH) and non-rush Hour (NRH) period. The results of PM1.0, PM2.5, PM4.0, PM10were in the range of 1.03 - 4.35μg/m3, 5.71– 70.15μg/m3­, 13.96­- 476.88μg/m3, 36.35– 1013.34μg/m3, respectively. The particulate concentration of PM10 was highest at TakieJunction.with a value of 1013.34 μg/m3while that of PM1.0 was found to be highest at Federal Government College (FGC) junction with a value of 4.35μg/m3. PM2.5 was also found to be highest at FGC junction with a value of 70.15μg/m3­and finally, PM4.0 was found to be highest at Takie junction with a value of 132.76 μg/m3. The highest value of PM10 with a value of 1013.34μg/m3 was due to traffic congestion, traffic intersection and dust from the untarred roads. PM2.5and PM10when compared with the standard provided by WHO (2006) showed that out of all the ten locations, Takie and FGC junction were above the standard for PM2.5 while Agbowo, Ojagbo, FGC, Arowomole, Takie, Arada, Orita Naira, Oke-Anu were above the standard for PM1