Spatial Variation of Air Quality in Mpape Area of Abuja, Nigeria

The study assessed air quality along selected area of interest in Mpape Area of the FCT, Nigeria. Particularly, it examined air quality variation in the heavily built areas, industrial areas, and control sites areas in Mpape. The experimental research was employed and air quality variables such as NH3, NO2, SO2, H2S CO2 and PM10 and PM25 were quantitatively gathered in the field using standard methods and equipments such as Minivol Portable Air Sampler, A set of Crow Can Dictator Meter, and GPS. Traffic volume along selected land uses in the three locations was obtained through traffic count approach. Data obtained were analyzed using averages, ANOVA, Pearson’s correlation, cluster analysis and Factor analysis. Across the studied locations, high content of carbon monoxide (CO2) was recorded in Arab Quarry District followed by Millennium Avenue and with mean values of 1.76 ppm and 1.50ppm respectively, while in the lowest concentration of CO2 was recorded in the Control site with a mean value of 1.18ppm. The range of SO2 in the present study is above FEPA recommended level of 0.10ppm. The range is also within WHO’s 24hrs allowable limit of 20ppm, the concentration of nitrogen dioxide (NO2) varied significantly among the different locations (F = 30.540, p<0.05). The concentration of ammonia (NH3) is ranged from 0.04 to 0.06ppm. The contents of atmospheric particulate matters (PM), PM2.5 and PM10 also varied among the selected locations. For PM2.5, it value ranged from 0.18 to 0.27μg/m3 which is slightly above the threshold of 0.25μg/m3 recommended by FEPA, mostly for ambient air quality in Angwan Gwari and Millennium Avenue areas. The range of PM2.5 is within WHO’s limit of 20μg/m3 for 24hrs mean concentration. Result of ANOVA showed that the concentration of PM2.5 varied significantly among the various locations (F = 10.758 p<0.05). Furthermore, for PM10, it value ranged from 0.16 to 0.26μg/m3 which is also slightly above the threshold of 0.25μg/m3 recommended by FEPA, mostly in Arab Quarry District and to some extent Angwan Gwari/ Millennium Avenue. These areas have increased concentrations of PM10. The range of PM10 reported in the present study is within WHO’s limit of 24hrs mean concentration of 50μg/m3. Also, result of ANOVA showed that the concentration of PM10 varied significantly among the various locations (F = 9.880 p<0.05). The result therefore means that Arab Quarry District and Angwan Gwari/ Millennium Avenue have high PM10 and PM2.5 concentrations. Cluster analysis classifies the principal pollutants of Mpape into two homogenous groups (SO2 and PM, and NO2) and also identifies anthropogenic activities (principally the combustion of fuel) as the primary source of emission of these groups of gases or pollutants into the atmosphere. Factor Analysis identified anthropogenic activities as the main sources of pollution of PM, NO2, SO2, NO and CO2 in Mpape environs. From the result of this research, there should be regular monitoring of atmospheric pollutants around the area in order to prevent the potential health and atmospheric related impacts of such air toxics in the region; Government should assist in the development of these new technologies that will enhance engine efficiency and reduce fuel consumption through the funding of research.