Estimation of local and external contributions of biomass burning to PM2.5 in an industrial zone included in a large urban settlement

A total of 85 PM2.5 samples were collected at a site located in a large industrial zone (Porto Marghera, Venice, Italy) during a 1-year-long sampling campaign. Samples were analyzed to determine water-soluble inorganic ions, elemental and organic carbon, and levoglucosan, and results were processed to investigate the seasonal patterns, the relationship between the analyzed species, and the most probable sources by using a set of tools, including (i) conditional probability function (CPF), (ii) conditional bivariate probability function (CBPF), (iii) concentration weighted trajectory (CWT), and (iv) potential source contribution function (PSCF) analyses. Furthermore, the importance of biomass combustions to PM2.5 was also estimated. Average PM2.5 concentrations ranged between 54 and 16 μg m−3 in the cold and warm period, respectively. The mean value of total ions was 11 μg m−3 (range 1–46 μg m−3): The most abundant ion was nitrate with a share of 44 % followed by sulfate (29 %), ammonium (14 %), potassium (4 %), and chloride (4 %). Levoglucosan accounted for 1.2 % of the PM2.5 mass, and its concentration ranged from few ng m−3 in warm periods to 2.66 μg m−3 during winter. Average concentrations of levoglucosan during the cold period were higher than those found in other European urban sites. This result may indicate a great influence of biomass combustions on particulate matter pollution. Elemental and organic carbon (EC, OC) showed similar behavior, with the highest contributions during cold periods and lower during summer. The ratios between biomass burning indicators (K+, Cl−, NO3−, SO42−, levoglucosan, EC, and OC) were used as proxy for the biomass burning estimation, and the contribution to the OC and PM2.5 was also calculated by using the levoglucosan (LG)/OC and LG/PM2.5 ratios and was estimated to be 29 and 18 %, respectively

The Determination of Mass, Element and Black Carbon Concentrations in Harmattan Aerosol Samples Collected at Kwabenya, Ghana

Aerosol particles were sampled between 27th December 2005 to 16th February 2006, using the Gent sampler and segregated into two size fractions – fine (PM2.5) and Coarse (PM10-2.5) from Kwabenya, near Accra. The aerosol particles were collected on Nuclepore polycarbonate mem-brane filters. The mass, Black Carbon (BC) and elemental concentrations in the two size frac-tions were determined using Gravimetric analysis, black smoke method and EDXRF analysis, respectively. The aerosol mass concentration was 8.57 μg/m3 for the fine fraction and 110.90 μg/m3 for the coarse fraction. The average Black carbon concentrations measured were 0.71 μg/m3 and 0.65 μg/m3 for the fine and coarse fractions, respectively. The results were compared with some literature values and the World Health Organisation Standard values. The high coarse to fine ratio suggest that most of the aerosol are from natural sources

Possible sources of atmospheric aerosol during 2005/06 Harmattan season at Kwabenya (Ghana)

Principal component analysis has been used to characterize and model aerosol particulate matter collected during the 2005/06 harmattan period. Species parameters determined by gravimetric, energy dispersive X-rays fluorescence (EDXRF) and reflectometric techniques were mass, elemental and black carbon concentrations. More than 26 elements were identified in the aerosol samples, but only 17 were used for the coarse fraction and 7 for the fine fraction models, because of detection limitation or missing values. The coarse fraction contained over 90 % of the mass, but the fine particle fraction has higher contribution of black carbon particles than the coarse fraction. Two source profiles were identified in the fine fraction of the aerosol and four source profiles in the coarse fraction. The experimental and modeled particulate mass correlated well, with 0.93 ≤ R2 ≤ 0.95. Journal of Applied Science and Technology Vol. 13 (1 & 2) 2008: pp. 55-6