Composition of Inhalable Atmospheric Particulates in Rustenburg, South Africa
Nnenesi A. Kgabi *
Department of Environmental Health Sciences, Polytechnic of Namibia, Private Bag 13388, Windhoek, 9000, Namibia.
*Author to whom correspondence should be addressed.
Abstract
In this study, inhalable particulate matter was sampled using the TEOM series 1400a, the elemental composition of the particulate matter was determined using Scanning Electron Microscopy coupled with Energy Dispersive Spectrometer (SEM/EDS) and the concentration of particulate nitrates and sulphates was analyzed using Ion Chromatography (IC). These parameters were evaluated to obtain an estimate of the composition of inhalable particulate matter (PM10) in Rustenburg, South Africa. The toxicity was also determined in terms of ratios of toxic metals to PM10, as well as to elemental carbon, nitrates and sulphates. The components of PM10 were obtained as follows: organic, halides, sulphates, crustal metals, toxic metals, nitrates, and carbon. The main toxic metals were obtained in order of decreasing abundance as Cr>Pb>Ni>V. Seasonal variations showed high levels of PM10 and sulphates in spring and high nitrate levels in summer. The SEM/EDS showed the presence of atmospheric particles of complex composition including S, Si, Al, Mg, Ca, Pb, Fe, Cr, Ni, V, and Pb.
Keywords: Inhalable particulate matter, toxic metals, particulate sulphates, particulate nitrates