Identification of aerosol particle sources in semi‐rural area of Kwabenya, near Accra, Ghana, by EDXRF techniques

Abstract

Small aerosol particles have for a long time been known to be harmful to humans, and are today regarded to cause a larger number of deaths than traffic accidents globally. Energy dispersive x-ray fluorescence (EDXRF) is a well known method that has been used for identification of toxic as well as non-toxic elements in the particles. The combination of elements will together with other information help to identify the sources and predict the effects of particles on environment and human health.The present work was conducted in Kwabenya, a suburb of the capital Accra of Ghana, which is frequently exposed to Harmattan dust from the Sahara-Sahel region. In total 171 filters each of PM2.5 and PM(2.5-10) were collected during 1 year. Levels of elements, black carbon (BC) and mass, were determined for both particle sizes. Principal component analysis (PCA) was performed on the datasets from Harmattan and non-Harmattan periods.The daily average of PM10 was very high, 179 µg m −3 and the BC contents were 4 µg m −3 . The presence of crustal elements was large in PM(2.5-10) as well as in PM2.5, and had a more than tenfold increase in PM(2.5-10) during the Harmattan period. Major characteristic elements for different sources were identified from correlation coefficients and regression analysis of the data. Sahara sand aerosol was the major source in both study periods, but influence from biomass burning, sea-spray and metal industries was also observed.

Biomass burning contribution to ambient air particulate levels at Navrongo in the Savannah zone of Ghana

“…The average PM 2.5 obtained for the sampling period was 32.4 mg/m 3 , which is higher than the World Health Organization (WHO) annual mean value of 10 mg/ m 3 and 24-hr mean of 25 mg/m 3 . The results of the species concentrations in this work compare well with other works in Ghana and Egypt (Table 2) (Ofosu et al, 2012;Aboh et al, 2009;Abu-Allaban et al, 2002).…”

Influence of the inter tropical discontinuity on Harmattan dust deposition in Ghana

“…[28] All material presented in this study indicates that long transported Harmattan dust do not deposit in southern Ghana when the ITD is positioned in its yearly average southernmost position around 5 N, contrary to what is concluded by, e.g., Aboh et al [2009] and Dionisio et al [2010]. Additionally the current results imply that the interpretation of the higher dust mass concentrations in the Harmattan season as reported by Afeti and Resch [2000] and Sunnu et al [2008] may be caused by dry convection rather than being long transported Harmattan dust.…”

“…All material presented in this study indicates that long transported Harmattan dust do not deposit in southern Ghana when the ITD is positioned in its yearly average southernmost position around 5°N, contrary to what is concluded by, e.g., Aboh et al . [] and Dionisio et al . [].…”

Impact of Sahara Dust Transport on Cape Verde Atmospheric Element Particles

“…Table 2 aimed to compare PM 10 total and element concentrations measured in Cape Verde with the concentrations measured in other sites of the globe. Results showed that PM 10 concentrations in Cape Verde were higher than concentrations measured in Europe and America, but lower than the concentrations measured in a suburban area in Ghana (Aboh et al, 2009); in Agra (India), which is bounded by the Thar Desert of Rajasthan (Kulshrestha et al, 2009); and in Hangzhou, an industrialized and urbanized region (Cao et al, 2009). A similar behavior was found for Fe.…”

“…Potassium concentrations were higher in Cape Verde compared with concentrations measured in Europe and America but lower than concentrations measured in Pakistan, Ghana, and China (von Schneidemesser et al, 2010;Aboh et al, 2009;Cao et al, 2009). Almeida and coworkers (2006b) indicated this element is associated with soil (insoluble coarse fraction), 244 M. ALMEIDA-SILVA ET AL.…”