DETERMINATION OF HEAVY-METALS IN SEA-WATER AND IN MARINE ORGANISMS BY FLAMELESS ATOMIC-ABSORPTION SPECTROPHOTOMETRY .9. DETERMINATION OF CADMIUM TRACES IN BIOLOGICAL-MATERIALS BY A SIMPLE EXTRACTION METHOD

This publication is a part of a series in which the author describes a set of methods for the determination of cadmium in environmental samples by means of flameless AAS. Common properties of these methods are their miniaturization and standardization. These have been attained by the utmost reduction of the number of steps and by their simplification. The method described in this publication consists of an acid digestion procedure followed by neutralization, extraction, and flameless AAS measurement. The main characteristics are: digestion takes place in small 1.5 ml tubes of quartz, polyvinyldifluoride or polypropylene. Neutralization is not performed by titration but only by an excess of saturated NaHCO3 solution. Extraction results are independent of pH in the region to be expected. Extraction is carried out by a (stable) solution of APDC in CCl4. The organic extract is also stable for at least 16h. Precision of the method lies in the range of 8.4%, at a concentration of 18.9 ng Cd g-1; sensitivity is at least in the range of 1.2 ng Cd g-1. The latter can be increased, if necessary, by a several-step extraction procedure. © 1979 Springer-Verlag.