Assessment of Heavy Metal Pollution in Roadside Soils of Ajdabiya City, Libya

Abstract

The assessment of some heavy metals contaminants in roadside soils is important part for controlling any excess in the environment especially if present in high concentration level, as it will affect human and animal health. This study was conducted at 15 different soil sample locations and divided into 4 zones in Ajdabiya city Libya. The study analyzed the eight heavy metals: Pb, Ni, Cu, Co, Cr, Mn, Cd, and Hg in soil samples. The EPA 3050 B (acid digested) method was used, and atomic absorption spectroscopy (AAS) was used to determine the metals. The pH of the soil samples was measured. The study evaluated the contamination factor (CF), the pollution load index (PLI), and the geo-accumulation index (I geo). The results show the mean metal concentration (µg/g) along roadside soils ranged from Pb: (0.0-607.65), Ni: (10.40-28.45), Cu: (208.30-3361), Co: (11.80-169.50), Cr: (215.50-345.35), Mn: (13.60-218.35), cadmium and mercury were not detectable. The result of the PLI in zone C is indicate strong sings of pollution (5.58), Zone B (2.29), Zone D (1.66) and Zone A (1.34) so, the pollution was due to anthropogenic impacted. The pH analysis shows most soil samples were alkaline ranging from (7.50 -9.6), because the pH of soils samples was alkaline that indicated the metals are strongly adsorbed (less soluble) and less mobile (immobilize metals) but can reduce availability of essential micronutrients such as, Cu and Mn.