Heavy metal pollution in soils along the major road networks: A case study from Rawalpindi
By: Aasma Bibi, Sofia Khalid, Khanorangah Achakzai
Key Words: Environmental pollution, Contamination factor, Pollution load index, Integrated pollution index
J. Bio. Env. Sci. 9(4), 141-148, October 2016.
Transportation is an important component of development and on-road transportation is the most essential and frequently used one. Apart from many services provided by the transport sector, it equally contributes to environmental pollution and is therefore considered as one of the significant sources of environmental pollution, posing various threats to the environment, human health and global climate. This study was an attempt to carry out an assessment of six heavy metals: Cu, Pb, Cr, Cd, Ni and Zn in the soil samples collected from different sites along the major road networks in Rawalpindi city, i.e. Murree Road, Islamabad Expressway, Grand Trunk Road and Rashid Minhas Road. After analyzing the heavy metals in the collected soil samples, various indices were computed in order to evaluate the impacts of heavy metal pollution and to categorize each site according to the traffic induced pollution burden, the indices computed were: contamination factor (CF), pollution load index (PLI) and integrated pollution index. The results indicated the contamination trend to be in the order: Murree Road > Grand Trunk Road > Islamabad Expressway > Rashid Minhas Road. The comparison of the results obtained for the samples collected from roadsides with those collected from the controlled site i.e. Morgah Biodiversity Park, showed that the greater pollution level along the roadsides may be due to the traffic loads on these roads.