Aerosol Chemical Characterization and Contribution of Biomass Burning to Particulate Matter at a Residential Site in Islamabad, Pakistan

Imran Shahid,Magdalena Kistler,Muhammad Zeeshaan Shahid,Hans Puxbaum

doi:10.4209/aaqr.2017.12.0573

Abstract

ABSTRACT Air pollution creates a very serious problem in developing countries, and scarce information is available about the nature of pollutants. This study describes the chemical composition of particulate matter (TSP and PM10), including marker compounds pointing to pollution sources, and estimates the contribution of biomass smoke to organic carbon (OC) and particulate matter (PM) at a residential site in Islamabad during the winter period in December 2007. Levoglucosan and its relationship with other anhydrosaccharides were used to estimate the biomass burning contribution, and polyols and primary and secondary saccharides were investigated regarding biological aerosol. Polyols and primary saccharides contribute a small fraction of the total PM10 and TSP mass, whereas anhydrosaccharides contribute more than 90% in both the PM10 and TSP. A significant contribution from biomass smoke has also been found in Islamabad, forming 10% of the TSP and 18% of the PM10 mass. The analysis of the distributions of saccharide concentrations between the TSP and PM10 fractions shows that anhydrosaccharides, viz., levoglucosan, mannosan and galactosan, all of which are directly related to the combustion of biomass, are mainly present in the PM10. The concentration of TSP varied from 218 µg m–3 to 468 µg m–3 (mean: 343 µg m–3), and PM10 concentrations were in the range of 89–304 µg m–3 (mean: 194 µg m–3). A good correlation was observed between PM10, TSP and Ca2+, which implies that mineral/road dust may be a major contributor to the PM in Islamabad.

Highlights

Atmospheric pollution is increasing day by day all over world due to rapid urbanization, industrialization and environmental degradation especially in developing countries like Pakistan, India and China
This study describes the chemical composition of particulate matter (TSP and PM10), including marker compounds pointing to pollution sources, and estimates the contribution of biomass smoke to organic carbon (OC) and particulate matter (PM) at a residential site in Islamabad during the winter period in December 2007
The analysis of the distributions of saccharide concentrations between the TSP and PM10 fractions shows that anhydrosaccharides, i.e., levoglucosan, mannosan and galactosan, all directly related to combustion of biomass are present mainly in PM10, which is in line with expectations for the combustion aerosol sizes (Hosseini et al, 2010)

Summary

INTRODUCTION

Atmospheric pollution is increasing day by day all over world due to rapid urbanization, industrialization and environmental degradation especially in developing countries like Pakistan, India and China. Shah and Zeeshan (2016) reported estimation of light-duty vehicle emissions in Islamabad and climate co-benefits of improved emission standards implementation and observed that highest overall emissions (59%) were on arterials, followed by residential roads (24%) and highways (17%) with higher emissions during morning (8–10 a.m.) and evening (4–6 p.m.) rush hours. All these studies over Islamabad has reported continuous degradation of air quality in the city, no study has given the comprehensive characterization of atmospheric aerosol and most of these studies are short-term. These samples were stored in a freezer and transported to Vienna, Austria, by air luggage for analysis

Experimental Methods Carbonaceous Species

AND DISCUSSION

Findings

CONCLUSION