Heavy Metal Contamination of Roadside Topsoil in North East Jordan

Environmental pollution of heavy metals from automobiles has attained much attention in the recent past, a study of heavy metals in roadside soils is critical in assessing the potential environmental impacts of automobile emission on soil. The present research was conducted to study heavy metals contamination in roadside soils of Mafraq-Zarqa highway in Jordan. The soil samples were collected and analyzed for the levels of Mn, Ni, Cu, Pb, Cd and Zn using flam atomic absorption spectrophotometer (AAS). The results showed that all heavy metals except Mn are lower than other studies. The results indicate the decreasing order of the average total metals content for the studied metals: Mn> Zn > Cu > Ni> Pb> Cd, higher levels of heavy metals east of the roadside were due to the westerly prevailing wind at the sampling site. The contamination decreased with distance from off the edge of the roadside and dropped to background level at about 60m west, also the contamination of the top soil was higher than the lower soil, finally the levels of heavy metals increased with increasing traffic densities and furthermore, they reached elevated levels in urban areas.