STUDIES ON THE DETERMINATION OF THE METAL CONTENT OF AIRBORNE-PARTICULATES BY FURNACE ATOMIZATION NONTHERMAL EXCITATION SPECTROMETRY

Quantifying the metal content of airborne particulates is of outstandi ng relevance because of its potentially toxic and carcinogenic behavio ur. The most widely used measuring strategy is based on filtration of particles from ambient air followed by analysis of the loaded filter t issue after wet digestion. In the present work an alternative approach was investigated which is based on drawing the air through the wall o f a porous graphite tube in such a way that particulates are collected on the inner surface of the tube. Moreover, the graphite tube acts no t only as an efficient collector but can also be employed as an electr othermal atomizer when applying furnace atomization non-thermal excita tion spectrometry. If combined with an echelle polychromator, simultan eous multi-element determinations are possible. The amount of metals i n air dust collected in this way were determined at the ng m-3 level, with limits of detection, calculated on the 3s criterion, ranging betw een 0.1 and 1 ng m-3. The precision represented by the relative standa rd deviation varied from 0.12 to 0.26 depending upon the concentration of metals in the air.