The determination of lead, chromium, arsenic and selenium in sediments and soil samples by electrothermal atomic absorption spectrometry using chemical modifiers

The effectiveness of some chemical matrix modifiers for the determination of lead, chromium,
selenium and arsenic in sediments and soils by Zeeman electrothermal atomic absorption
spectrometry have been evaluated. The addition of certain chemical modifiers decreases the
volatility of the analyte element, preventing its loss during pyrolysis step while increasing the
volatility of matrix components promoting a better separation also allows a higher pretreatment
temperature for better separation between analyte and matrix. Pyrolysis and atomization
temperatures, characteristic masses and detection limits of analytes in dissolved samples with
and without modifiers have been compared. The method was validated by analysing certified
reference lake sediment and soil materials.