Performance of selected destruction methods for the determination of heavy metals in reed plants (Phragmites australis)

The aim of this study was to assess the performance of selected destruction methods for the determination of heavy metals in reed plants (Phragmites australis (Cav.) Trin. ex Steudel). Homogenised samples of stems and leaves were subjected to six destruction methods and analysed for Cd, Cu, Pb, Zn, Ni, Cr, Fe and Mn. A microwave destruction procedure yielded the best overall recoveries. An overnight destruction with HNO3 and a destruction using HNO3 and H2O2 yielded Cd, Cu, Pb, Zn, Fe and Mn recoveries which could be acceptable for some purposes. For these elements, both methods could be used as relatively cheap, easy and fast substitutes for microwave destruction. A destruction using HNO3 and HClO4 is not recommended for the determination of Pb in reed plants, whereas dry ashing procedures were suitable for none of the elements. For the determination of Ni and Cr in reed plant material, microwave destruction appeared the only acceptable method. Heavy metal analysis of reed plants significantly depends upon the destruction procedure used. There is a need for certified reference reed samples for quality control. (C) 2003 Elsevier B.V. All rights reserved.