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The present study describes the characterization of carbonaceous species including elemental carbon (EC), organic carbon (OC), total carbon (TC), crustal (Al, Ca, Mg, Fe, S, and Ti) and trace metals (As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sn and Zn) in PM 10 samples collected from an urban site in Lahore, Pakistan. Sources of various pollutants and their characterization positive matrix factorization (PMF) model. The carbonaceous species (TC, OC, EC) and metals were measured in PM 10 samples by NIOSH protocol using Sunset lab instruments and ICP-OES respectively. PM 10 concentrations varied from 254 to 555 µg/m 3 with an average of 406 ± 87 µg/m 3 . The elemental carbon (EC) concentration varied from 3 to 56 µg/m 3 with an average of 21 ± 15 µg/m 3 . While the organic carbon (OC) concentrations varied from 21 to 212 µg/m 3 with an average of 63 ± 42 µg/m 3 . The OC/EC ratio varied from 1.5-7.6 with an average of 3.9 ± 1.6, indicating a contribution of both biogenic and secondary aerosol formation. A good correlation was also observed between EC and OC (R 2 = 0.81) indicating their common origin. PMF has identified industrial dust (18.2% of PM 10 ), vehicular emission (26.5% of PM 10 ), bio mass fuel (24.3% of PM 10 ) and re-suspended dust (4.6% of PM 10 ) as major sources of PM 10 in urban environment of Lahore.

Particulate matter (PM) plays a vital role in altering air quality, human health, and climate change. There are sparse data relevant to PM characteristics in urban environments of the Middle East, including Peshawar city in Pakistan. This work reports on the morphology and composition of PM in two size fractions (PM2.5 and PM10) during November 2016 in Peshawar. The 24 hous mass concentration of PM2.5 varied from 72 μg m−3 to 500 μg m−3 with an average value of 286 μg m−3. The 24 hours PM10 concentration varied from 300 μg m−3 to 1440 μg m−3 with an average of 638 μg m−3. The morphology, size, and elemental composition of PM were measured using Fourier Transform Infra Red (FT-IR) Spectroscopy and Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX) Spectroscopy. The size of the analyzed particles by EDX ranged from 916 nm to 22 μm. Particles were classified into the following groups based on their elemental composition and morphology: silica (12%), aluminosilicates (23%), calcium rich (3%), chloride (2%), Fe/Ti oxides (3%), carbonaceous (49%), sulfate (5%), biogenic (3%). The major identified sources of PM are vehicular emissions, biomass burning, soil and re-suspended road dust, biological emissions, and construction activities in and around the vicinity of the sampling site.