Abstract

Atomic absorption spectroscopy (AAS) was used to determine the aerosol metal constituent and elemental concentration for 11 elements in air at Okigwe (Lat. 5.40°N, 6.30°N and Long. 7.05°E, 7.35°E) during the 2007/2008 harmattan. The dust sample was collected by direct deposition method under gravity on a Whatmann filter paper. The dust sample was collected for a period of 24 h per day for a total of 30 days starting from February 4 - March 5, 2008. The mass and mass concentrations obtained are 0.0510 g and 8.02 × 10^-4 g/cm² respectively. The elemental constituent and concentration in mg/kg obtained during the period are 9666.67 for calcium (Ca), 2059.80 for potassium (K), 1396.08 for magnesium (Mg), 8678.43 for Iron (Fe), 20.59 for Zinc (Zn), 69.61 for Manganese (Mn), 94.16 for Copper (Cu), 200.96 for nickel (Ni), 190.20 for chromium (Cr), 8.82 for cadmium (Cd), and 4.90 for lead (Pb). A comparison of reported results from Uturu Abia State, Nigeria (05.33°N, 06.03°N, and 07.10°E, 07.29°E) and that obtained at Okigwe, Nigeria showed some differences in the concentrations and this is explained in terms of the latitudinal locations of the stations with respect to the aerosol source.

Key words: Aerosol metal constituent, concentration, atomic absorption spectroscopy (AAS).