Modification of electrothermal atomic absorption spectrometry for determination of arsenic in high salinity samples

The electrothermal atomic absorption spectrometry (ET-AAS) method was optimized for determination of the arsenic content in high salinity samples. The combination of palladium (1 g/l) modifier, graphite furnace temperature program and graphite tube modified with tungsten carbide significantly reduced the matrix interference in the sample with NaCl concentration of 10 g/l. Optimized temperature program ensured the reduction of the background absorbance about 95–100%. The modification of graphite furnace surface by tungsten carbides ensured the shift of background absorbance prior to the absorbance of the analyte and considerable extension lifetime of graphite tubes.