Particulate Matter (PM) strongly affects the living beings and climate of a particular region or area.
Current research work emphasizes on calculation of mass concentration, size distribution,
chemical composition and the source apportionment in provincial capital of Pakistan (Lahore).
The PM was collectedusing MOUDI Impactor rotating model 110 – R for a specific time period
i.e. from November, 2016 to February, 2017. The average standard deviation in mass
concentrations of total suspended particulate matter (TSPM), coarser particulate matter (PM10),
fine particulate matter (PM2.5) and ultra-fine particulate matter (PM0.1) were observed to be 932.36
± 70.82, 517.77 ± 35.27, 210 ±17.77 and 204.59 ± 17.78µgm-3, respectively. TSPM, PM10, PM2.5
and PM0.1 samples were analyzed chemically for 23 elements including Na, P, K, S, Ca, Mn, Fe,
Cu, Zn, Ga, As, Sr, Pb, Cl2, Cd, Cr, Sb, Sn, Se, Mg, Ni, Ba and Al using X-ray fluorescence
spectrometry (XRF). The crustal enrichment factors (EF) were calculated using Fe as a reference
for the trace metal species to identify the sourcesas crustal elements with EF ≤ 1, weak crustal
elements with 1 ≤ EF ≤ 5 and non-crustal elements with EF > 5. US-EPA Positive Matrix
Factorization (PMF) model was used for source apportionment of PM10, PM2.5 and PM0.1. Five
possible sources were analyzed in PM10, PM2.5 and PM0.1 and observations reveal that road and
industrial dust, vehicular emissions, iron and steel industry, oil burning in various sectors and
biomass burning contribute 26.84, 29.4, 14.3, 15.8 and 13.7% to PM10 mass, 28.5, 25.2, 19.1, 110.3
and 16.8% to PM2.5 mass and 27.4, 23.3, 17.6, 21.7 and 10% to PM0.1 mass, respectively. NOAA
HYSPLIT online model was run for time duration of 24 hours using GDAS Meteorological Data
over three heights i.e. 500, 1000 and 1500 m from the sea level. Moreover, the backward trajectory
analysis after adjusting the geographical location of Lahore at 31.93N to 74.58E, suggested that
PM sources are located at Indian Punjab, Jammu Kashmir, Afghanistan, deserts of Sindh, cities of
Pakistan located at motorways, GT road and local sources of Lahore itself.
Keywords: Particulate Matter; Mass concentrations; GDAS Meteorological Data; Climate
change.