COMPARISON OF PROCEDURES FOR CORRECTION OF MATRIX INTERFERENCES IN THE MULTIELEMENT ANALYSIS OF SOILS BY ICP-AES WITH A CCD DETECTION SYSTEM

Three procedures, matrix matching, plasma optimisation and single-poin t standard-addition, have been evaluated to ascertain the best procedu re for simultaneous multi-element analysis of industrial soils by ICP- AES with CCD detection. A standard reference material, CRM143 from the Bureau Communautaire de Reference (BCR), has been analysed for Cd, Cr , Cu, Mn, Ni and Pb using the three different matrix interference corr ection procedures. All three procedures give comparable results which are in good agreement with the BCR values, except for Cr. The single-p oint standard addition procedure was chosen, on the basis of economy a nd ease of implementation, to correct for matrix interferences in the determination of Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sn and V in soil samp les collected from an industrial site in England. Concentrations of so me of the elements were found to vary greatly with sampling depth. For example, the concentration of Mn, determined using the atomic line at 279.920 nm, increased from 426 +/- 3 mu g/g at a depth of 18-28 cm to 5996 +/- 144 mu g/g at 60-85 cm.