Evaluation Of Heavy Metal Contamination Of Roadside Soils Of Selected Areas Of Islamabad

Abstract

Environmental pollution from heavy metals emitted by automobiles has garnered significant attention recently, Vehicle emissions release harmful metals into the environment, and roadside soils can serve as long-term reservoirs for these non-biodegradable metals. The main goal of this research is to quantify toxic heavy metals along the roadside soils of Islamabad and measure its physical parameters. Using a soil auger, roadside soil samples were taken from 20 locations in Islamabad down to a depth of 15 cm. Each sample consisted of 3 cores taken from the roadside with equal intervals to analyze the spatial distribution of metal trace element (MTE) in the soils. These samples were analyzed for Nickel (Ni) and Copper (Cu) by atomic absorption spectrophotometer. From the results, it was found that copper had the highest concentration, which varied from 2-722 ppm, and the average concentration was found 64.48 ppm whereas, Ni concentration ranged from 1-59 ppm and the average concentration was found to be 24.8 ppm. The levels of Cu were found to be higher, and the levels of Ni were found to be lower as compared to WHO permissible limits of 36 mg/kg and 35 mg/kg, respectively. The physical parameters (pH, electrical conductivity, TDS, and salt) of all the samples were also measured. The pH values ranged from 6.51-7.45, electrical conductivity ranged from 163.1-988 µS, TDS ranged from 116-701 ppm and salts ranged from 78.8-481 ppt. The average values for pH, electrical conductivity, TDS, and salts were 7.0735, 349.98 µS, 248.35 ppm, and 167.515 ppt, respectively. The differences in elemental levels across the sampling points mirrored the differences in traffic density. Thus, it is advised that stringent laws be put into effect to monitor the life span of vehicular components, such as tyres, brake pads, and engines, to prevent the release of heavy metals like nickel and copper into the atmosphere from worn-out parts. Additionally, heavy-metal levels on major roads in Islamabad should be monitored and soil quality must be maintained regularly.