A comparison of waste recycling facilities for their contribution of heavy metals and trace elements in ambient air.

Abstract

A multi-elemental analysis, including heavy metals and trace elements in ambient air samples, was conducted for computers, wires, lead batteries, and iron extraction facilities in Lahore by proton-induced X-ray emission (PIXE) spectroscopy. The data obtained from PIXE analysis revealed the presence of Mg, Al, Zn, S, Pb, K, Ti, Fe, Si, K, and Cr elements at e-waste recycling facilities. The computer dismantling site revealed a higher concentration of Fe (634.7 μg/m3), Al (176.8 μg/m3), Pb (135.4 μg/m3) and Zn (122.5 μg/m3) in the air samples. The decreasing order of heavy metals and trace elements contribution at the computer dismantling site was as Si > Fe > Al > Pb > Zn > Mg > Ca > Cr > K > S > Ti. Similarly, at wires/cables burning site, a higher concentration of Fe, Al, and Pb (829.8 μg/m3, 184.5 μg/m3 and 115.6 μg/m3, respectively) were observed, and the elements revealed a descending trend as Si > Fe > Al > Zn > Pb > Mg > Ca > Cr > Ti > K > S. The lead batteries dismantling site showed the highest Pb concentration (141.2 μg/m3) due to the disassembling of lead acid batteries. Al, Zn, Fe, and Cr also revealed higher concentration in air samples and exhibited a declining trend as Si > Fe > Al > Pb > Zn > Cr > Ca > Mg > Ti > K > S. However, the highest concentration of Fe (865.7 μg/m3) was detected in air samples of iron extraction sites besides Al and Zn. The descending order of trace elements contribution was Si > Fe > Al > Zn > Mg > K > Ca > Ti > S. Furthermore, the correlation between workers' awareness and their possible health impacts were also examined in the study. Most of the workers were less aware of the hazardous impacts. Majority of workers and residents were suffering from a respiratory illness (27.5% and 32.5%), kidney failure (15% and 22.5%), and neurological disorders (15% and 7.5%), respectively, due to exposure of airborne particulate matter which could be correlated with the higher concentration of heavy metals such as Pb, Cr, Zn, and Fe in the ambient air at the e-waste recycling sites.