COMPARISON OF DIGESTION PROCEDURES FOR THE DETERMINATION OF HEAVY-METALS (CD, CU, PB) IN BLOOD BY ANODIC-STRIPPING VOLTAMMETRY

The simultaneous determination of cadmium, lead and copper in whole blood by anodic stripping voltammetry is described. Different digestion procedures given in literature were examined. In addition, a sample pretreatment method which did not involve digestion was studied. Based on the experience with these methods two digestion procedures were developed. They utilize digestion with mixtures of nitric, perchloric and sulphuric acids, with and without pressure, respectively. Both methods are suitable for routine analysis of about 20 blood samples per day. Special attention was focussed on the completeness of the digestion, and the magnitude of the blank values. Low blank values and a high sensitivity allowed the determination of cadmium at the sub-ppb level with an electrolysis time of 5 min. The methods, which were controlled by recovery tests, were used to analyze blood samples from unexposed persons, and from workers suspected of exposure to cadmium. © 1979 Springer-Verlag.