Contamination Assessment of Heavy Metals in Road Dust of the University of Nigeria, Enugu Campus, Southeastern Nigeria

2018 Australian Journal of Basic and Applied Sciences  
Heavy metals concentration in the environment is increasingly becoming a health concern in the world for humans and a disruptor of the ecosystem. This is particularly observable in street dust of urban cities and settlements with high density traffic. Road dust samples were analyzed for determination of concentrations of the environmentally sensitive elements, Co, Cr, Cd, Ni, Pb, Fe, Mn and Zn in fraction of dust smaller than 100 μm. The dust particles were collected during the dry season along
more » ... the road in office complexes, residential, construction sites, business centers and classroom areas representing different activities across the University of Nigeria Campus located in an urban city, Enugu, southeast Nigeria. The road dust was collected near the curb and 1 m from the curb on the road. The dust samples were measured for their heavy metal concentration and contamination levels. The assessment of heavy metal pollution was based on such geochemical models as single pollution indices (Contamination Factor and enrichment factor), integrated pollution index (degree of contamination (Dc)) and Pearson moment correlation in order to determine their possible source and spatial distribution. The results obtained after acid digestion and metal determination with an atomic absorption spectrophotometer gave the following mean values for Co, Mn, Zn, Ni and Fe: 11.53, 99.92, 221, 44.23 and 216 mg kg -1 respectively from samples near the curb and 12.37, 92.25, 248.87, 43.62 and 197.5 mg kg -1 respectively from samples 1 m from the curb. The mean values for the physico-chemical parameters obtained which include electrical conductivity (EC), pH and total organic matter (TOM) are 304μS/cm, 7.13, and 6.9% respectively from samples near the curb and 408μS/cm, 7.33 and 5.57% respectively for samples 1 m from the curb. The general pattern of occurrence of heavy metals on the two road positions follows a similar order of Zn>Fe>Mn>Ni>Co>Pb>Cd>Cr. The highest levels of Cr, Zn and Ni were found in the high traffic density areas, and strong positive correlations were found between these metals. These results suggest diverse origin of pollution sources which include human activities, vehicular emissions and lithogenic occurrences of the metals from road construction currently in some of the sites sampled.
doi:10.22587/ajbas.2018.12.12.1 fatcat:lqmyy2pzd5evzg4az2es6vi6wq