A STUDY ON ROAD TRAFFIC EMISSIONS OF HEAVY METALS IN THE TIRANA- ELBASAN HIGHWAY TUNNEL EXPERIMENT IN ALBANIA BY USING THE DUST SAMPLES

摘要

To identify the tracer emission from the diesel engines and to evaluate the environmental pollution caused by traffic emission inside the tunnel, fine particulate matter (PM) samples collected in the tunnel of Krraba (Tirana-Elbasan highway) were analyzed for heavy metals content (Cu, Fe, Hg, Pb, Mn, Ni, and Zn) in relation to different distances from the entrance portal to the exit portal of the tunnel. The horizontal ventilation systems of the tunnel, located next to the tunnel portals, were not permanently function during the both monitoring periods. Dust samples collected in front of the entrance portal show low metal content that is gradually increased as the distance from the entrance to the exit portal increased. High contents of metals in dust samples were found that indicates the dust samples are efficient to be used for the monitoring of heavy metal pollution caused by tunnel’s traffic exhausts over the time, even with low sensitivity analytical methods. The data onto two different monitoring periods shows different views of metal distributions. The first monitoring period (November 2013) is characterized by high Fe content in dust samples, by indicating the high effect of soil dust caused by construction activity during this monitoring period. The second monitoring period (March 2014) is characterized by higher content of Cu, Hg, Zn and Mn that are typical elements of the anthropogenic sources related mainly to traffic emissions. The multivariate analysis of dimensionality reduction technique, factor analysis (FA), was used to identify the most potential factors of these tracers. The FA and Cluster analysis of trace metal concentrations data show that the Hg and Pb onto PM samples, are probably linked with the diesel engine emissions.