Comparison of dissolution methods for multi-element analysis of some plantmaterials used as bioindicator of sulphur and heavy metal deposition determined by ICP-AES and ICP-MS

Most analytical methods for trace element determination in plant material r equire decomposition of the sample. Sample decomposition procedures play an important role in ensuring that chemical analysis gives correct results. T his is especially important in the determination of trace elements in plant material for environmental studies because, as a rule, plant material is n ot homogeneous and usually contains variable matrices. In this paper microw ave digestion procedures using HNO3, HNO3+H2O2, HNO3+HClO4, HF mixtures and dry ashing + HF were investigated for the analysis of Al, Ca, Cr, K, Mg, M n, Zn, S, Pb, V, Cu, Cd, Co and Ni by ICP-AES or ICP-MS from pine needle sa mples. Reference samples BCR CRM 100 (Spruce Needles), BCR CRM 101 (Beech L eaves) and HUMH2 (Organic surface soil) were used to test the dissolution m ethods. The results showed that the sample digestion procedure is critical step for obtaining accurate results. Losses of volatile metals were notable in many cases when dry ashing was used.