ELEMENTAL CHARACTERIZATION OF AIRBORNE-PARTICULATES AT 2 NIGERIAN LOCATIONS DURING THE HARMATTAN SEASON

Airborne particulate matter collected during the Harmattan season at Kano in the northern part, and Ile-Ife in the southern part of Nigeria was analyzed for about 30 elements by a combination of instrumental neutron activation analysis and X-ray fluorescence analysis. Although the total suspended particulate concentration (ng/m3) is much higher in Kano than Ife, the elemental composition at both locations is very similar and cluster analysis shows a strong correlation between the two, indicating a common origin for particulates. Particle-size distribution studies show that Kano dust is mainly coarse while Ife dust is mainly fine. The crustal-type elements are mainly concentrated in the coarse particles (greater-than-or-equal-to 3 mum) at both locations while the conventional anthropogenic elements are hosted mainly by the fine particles (0.49 mum and below).