SLURRY SAMPLING FOR THE DETERMINATION OF LEAD, CADMIUM AND THALLIUM IN SOILS AND SEDIMENTS BY ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRYWITH FAST-HEATING PROGRAMS
I. Lopezgarcia et al., SLURRY SAMPLING FOR THE DETERMINATION OF LEAD, CADMIUM AND THALLIUM IN SOILS AND SEDIMENTS BY ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRYWITH FAST-HEATING PROGRAMS, Analytica chimica acta, 328(1), 1996, pp. 19-25
To determine the lead and cadmium content of soils and sediments, the
samples are suspended in water containing 5% (v/v) concentrated hydrof
luoric acid before injected into the electrothermal atomizer. For thal
lium determination a 30% hydrofluoric acid solution is used as the sus
pension medium. In accordance with fast-heating methodology, the conve
ntional ashing step is replaced by a modified drying stage performed b
y programming the instrument to 400 degrees C. No modifier other than
hydrofluoric acid is required. Calibration is performed directly using
aqueous standards for cadmium and lead determination. For thallium th
e standard additions method is recommended. The results obtained for f
ive certified reference materials show the reliability of the procedur
es.