EDXRF elemental assay of airborne particulates: A case study of an iron and steel smelting industry, Lagos, Nigeria

Abstract

The unregulated activities of a scrap iron and steel smelting industry in Lagos, Nigeria necessitated the sampling of PM₁₀ and PM_2.5 particulates from various sections of the industry. The samples were analyzed using polarized energy dispersive x-ray fluorescence (EDXRF) technique which allowed the simultaneous detection of over 25 elements in all the samples. The mass concentration levels ranged from 86 µg/m³ to 8255 µg/m³ for PM₁₀ and 10 µg/m³ to 462 µg/m³ for PM_2.5. The highest concentrations of 8255 µg/m³ and 462 µg/m³ for PM₁₀ and PM_2.5 respectively were observed at one of the electric arc-furnaces (EAF-2). This was observed to be as a result of the scrap and additives used here and of the highest rate of emission. The observed higher concentrations of PM₁₀ Pb at various sites when compared with the USEPA standard of 1.5 µg/m³ suggest immediate repair or replacement of the emission control devices.

Keywords: PM₁₀, PM_2.5, polarized EDXRF, toxicity potential, electric arc-furnace, turboquant.