Determination of heavy metals in samples of urban solid wastes by means of the ICP atomic spectrometry technique

The concentration of elements of environmental significance in the leachate from landfills of urban solid wastes was determined by means of Inductively-Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The suitability of extraction tests which simulate the leaching process were undertaken. Both highly toxic elements (As, Cd, Co, Cr, Pb and V) and elements present at major concentrations (Al, B, Cu, Fe, Mn, Ni and Zn) were quantified at different levels within and under the landfill. Results showed that the extraction test recommended by EPA is acceptable in order to simulate natural leaching compared with the amounts of the elements which are brought into solution after digestion with nitric acid. Furthermore, significant correlations were found in the landfill composition at different levels for element pairs such as Al-Mn, Co-Cr, Co-Cu, Co-Fe, Co-Mn, Co-Zn, Cr-Fe, Cr-Mn, Cu-Fe, Cu-Zn, Fe-Mn, Fe-Zn, Mn-Zn and Pb-Zn.