Determination of heavy metals in soils, sediments and geological materials by ICP-AES and ICP-MS

Sixteen soil and sedimentary geological reference materials were analysed for As and the heavy metals Cd, Co, Cr, Cu, Ni, Pb and Zn by inductively coupled plasma-atomic emission spectrometry (ICP-AES) and inductively coupled plasma-mass spectrometry (ICP-MS) in combination with total and partial dissolution of the samples, It can be demonstrated that none of the modern ICP methods is completely free from analytical problems. This applies in particular when the concentrations are close to the detection limits (e,g, in ICP-AES) and is mainly due to the wide variation in the bulk composition of soils resulting in complex matrix effects (e,g. in ICP-MS), In order to determine the extent of soil pollution by heavy metals, both partial and total dissolution have to be performed prior to analysis.