Soil Contamination Due to Heavy Metals atElectronicWaste Dumpsites in Karachi, Pakistan

The Shershah market is the oldest and largest scrapmarket in the Karachi city. The recycling,dismantling and burning of electronic waste(e-waste)in and around the market are causing thesignificant environmental and human health risk. Furthermore, it is estimated that around 1-2million people daily pass through the market,since it is situated at the linked road, connectingthree towns i.e. Baldia, S.I.T.E and Lyari. The present study was designed to explore the level ofheavy metals (Cd, Cr, Cu, Fe, Ni, Pd and Zn) contamination from the e-waste produced in themarket. Therefore, the two dumping sites were selected and the sampling was carried out from thesurface and depth of the soil biannually from 2015 to 2018. The assay was carried out by AtomicAbsorption Spectroscopy (AAS). A control sample had also been taken from the non-e-waste site.Heavy metal concentration (mg.kg-1) in the soil surface samples were found as Cd (0.63-0.26), Cr(2.91-0.78), Cu (332.42-46.51), Fe (6.63-2.97), Ni (5.74-3.42), Pb (111.93-66.45) and Zn (125.41-74.69), and for thedepth samples, the heavy metals were as Cd (0.41-0.12), Cr (1.39-0.18), Cu(86.24-6.98), Fe (4.65-1.11), Ni (2.38-0.88), Pd (71.59-19.24) and Zn (44.19-9.63), respectively.The insignificant concentration of the metals was analyzed at the control site. Thedata wascompared with the international standards i.e. USEPA standards, FAO/WHO guidelines, EUguidelines etc. The level ofPband Cu was higher than the allowable limits, indicating the riskassociated with the soil and to the local public. Therefore,the e-waste dumpsites should be shiftaway from the city.