Contamination of Two Heavy Metals in Topsoils of the Urban Parks Asadabad, Iran 2013

Background & Aims of the Study: Heavy metals are the most important contaminants inthe soil. Due to their non-biodegradable property, heavy metals can persist in the ecosystemfor a long time. Therefore, this research focuses on heavy metal contamination in urbanpark soils in Asadabad, Hamedan, Iran.Materials & Methods: Altogether 18 composite soil samples were collected at depths 0-20cm from urban parks. The urban soil samples were digested in aqua regia according to11466 ISO standard methods. Total concentrations of Cd and Pb were measured by AtomicAbsorption Spectrometer.Results: Concentrations of Cd and Pb varied in the range of 0.15-0.22 and 7.5-27.5 mg/kg,with mean values of 0.18 and 20.72, respectively. The mean values of geo-accumulationindex ( Igeo) were (-0.70) and (0.04) for Cd and Pb respectively. The urban soils inAsadabad, Iran, were uncontaminated by Cd and uncontaminated until moderatelycontaminate with Pb. There was no significant correlation between Pb and Cd (r2=0.16), itseems that these metals may have derived from different sources.Conclusions: Findings showed that Cd was usually associated with parent material in thesoils, while Pb was controlled by anthropogenic activities such as traffic and residentialwastes. Also the results indicated that urban park s location affects the total metal contentsof the analyzed soils.

Keywords:

Soil pollution , HeavyMetals , Lead , Cadmium , Urban Parks , Iran