TRANSVERSELY HEATED GRAPHITE ATOMIZER ATOMIC-ABSORPTION SPECTROMETRY (THGA AAS) IN COMBINATION WITH FLOW-INJECTION ANALYSIS SYSTEM HYDRIDE GENERATION (FIAS HG) AS A RELIABLE SCREENING METHOD FOR ORGANOLEAD COMPOUNDS

The combination of a flow injection analysis system-hydride generation (FIAS HG) and transversely heated graphite atomizer-atomic absorption spectrometry (THGA AAS) has been applied for the sensitive detection of organolead compounds [e.g. detection limit of trimethyl-lead specie s (TriML): 32 ng l(-1) for a 0.5 ml sample loop in the presence of ino rganic lead. A mixture of hydrochloric acid and ethylenediaminetetra-a cetic acid (EDTA) as a carrier solution in the flow injection system s uppressed interferences of inorganic lead. Calibration with various or ganolead compounds in the range 0.25-8 mu g l(-1) was carried out in t he presence of 10 mg l(-1) Pb2+ without any interferences. Additionall y, statistical aspects of the determination of trimethyl-lead have bee n studied. Different parameters, e.g. working range, detection limit, recovery function etc., were calculated with respect to quality assura nce in metal speciation.