Open wet ashing of some types of biological materials for the determination of mercury and other toxic elements.

ABSTRACT

An open wet decomposition procedure for trace element analysis of biological material has been worked out. It is based on the utilization of nitric acid, hydrochloric acid and hydrogen peroxide and is well suited for the determination of As, Bi, Cd, Cr, Hg, Pb, Sb, Se and Tl. For these elements the recoveries were examined by the radiotracer technique, with lichens, pine needles, grass and human hair as representative biological samples. In addition to the conventional labelling technique, use was also made of in situ labelling. In all cases, recoveries between 93 and 100% were achieved, which are adequate for quantitative trace element analysis.