Characterization of Atmospheric Particulate Matter at E-Waste Landfill Site in Agbogbloshie, Accra

Abstract

A year-long investigation has been carried out on atmospheric particulate matter (APM). Elemental composition,mass concentration, sources contributions and their ngerprints were determined in APM samples collected, in Agbogbloshie scrap market, between May 2010 and April 2011. PM2:5 and PM102:5 size fractions of APM were collected 24-hourly on 47 mm diameter nuclepore lters of pore sizes 0.4 μm and 8 μm respectively, using the Gent sampler. Gravimetric analyses were carried out to determine the APM mass concentrations. The minimum, maximum and annual mean mass concentration values for PM2:5 obtained for the sampling site throughout the period of investigation were 35.43 ( g=cm3), 349.68 ( g=cm3) and 88.62 ( g=cm3) respectively. For PM10��2:5, the minimum, maximum and annual mean mass concentration values obtained were 76.83( g=cm3), 448.67 ( g=cm3) and 138.31 ( g=cm3) respectively. These measured concentration levels are all substantially higher than the WHO, USEPA, EU, JAPAN EQS, UK National Air quality objective, World Bank and Canada air quality standards. Particle Induced X-Ray Emmission (PIXE), Particle Induced Gamma Emmission (PIGE) and Energy Dispersive X-Ray Fluorescence (EDXRF) were used to determine elemental composition and concentration of the atmospheric particulate matter. The ve most abundant elements in coarse fraction PM102:5 are Si average 6545.05 (range: 261.3359950.56) ngm��3, Al average 3743.25 (range: 218.9424719.25) ngm��3, Fe average 12464.77 (range: 182.0818982.45) ngm��3 , Cl average 5918.47 (range: 587.76 15796.13) ngm��3, Na average 4040.17, (range: 418.2515010.32) ngm��3. In the ne fraction (PM2:5) concentrations reordered were in the following order: Si average 5466.44 (range: 1339.9361029.16) ngm��3 , Al average 3073.44 (range: 888.7425389.05) ngm��3, Fe average 1877.57 ( range : 769.2819569.65) ngm��3, Cl average 4972.86 (range: 1533.3616741.73) ngm��3, Na average 3163.27 (range: 1295.1515887.22) ngm��3. Enrichment Factor evaluation was rst used as one of the means to separate elements in terms of natural and anthropogenic sources. PMF was employed in ngerprint and source contributions identi cations, PMF resolved ve sources each for both PM2:5 and PM10��25. The following sources were identi ed for the PM2:5:E-waste burning (49%), Industrial activities (23%), vehicular tra c (16%), resuspended dust (7%) and sea spray (5%). In the coarse fraction, soil dust (45%),biomass burning (17%), Heavy oil burning (16%),sea spray (12%) and e-waste burning (10%) were apportioned. Natural sources (45%) were the major contributors in the coarse fraction while anthropogenic sources(88%) were the major contributors in the ne fraction. E-waste burning contributions were identied in both fractions. In this work, the following elements (Zn, As, Br, Sn, Cd, Hg, Pb) have been identi ed as ngerprint for e-waste burning and this source contributed 49% of the pollutants identied in the study area.