DETERMINATION OF CHROMIUM, MANGANESE AND VANADIUM IN SEDIMENTS AND SOILS BY MODIFIER - FREE SLURRY SAMPLING ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY

Slurried sediment and soil samples of the certified reference material s with a highly elevated level of the metals of interest (Mn, Cr and V ) were analysed by electrothermal atomic absorption spectrometry (ETAA S) with Zeeman effect background correction. The method of slurry prep aration and time-temperature programmes were optimized and, finally, t he use of chemical modifiers was not necessary. The effect of alternat e spectral lines and gas mini-flows on characteristic masses of analyt es was studied. The homogeneity of samples and the influence of short sample grinding were also discussed. The simple, aqueous standard base d calibration graphs (except Mn at the concentration > 1000 mg kg(-1)) were applied for the quantification of results. The results of determ inations obtained by slurry sampling agreed well with the cetified val ues, and the relative standard deviations (RSDs) for the over-all anal ytical procedure repeatability (at slurries concentration level about 2 mg/2 ml) were less than 9.5%, except manganese (10.4%). (C) 1998 Els evier Science B.V.