Determination of Arsenic, Selenium and Antimony in Natural Waters by Batch Hydride Generation Atomic Absorption Spectrometry Equipped with Flame Heated Quartz Tube

Abstract

This paper presents an analytical method for arsenic, selenium and antimony in natural water samples using batch hydride generation atomic absorption spectrometry equipped with a flame heated quartz tube.
The system is applicable for the measurement of sub μg/L level of these elements in water samples. The concentration of hydrochloric acid in the sample and amount of injected sodium borohydride was optimized for each element. For complete reduction of antimony (V) to stibine, both potassium iodide and thiourea were found effective. Reduction of selenium (VI) to selenium (IV) was accomplished by heating the sample in 6M hydrochloric acid to 90°C for 20 to 30 min. This method was then applied to environmental samples. Arsenic was found in a range of sub μg/L in fresh water samples and a few μg/L in sea water samples. Selenium was not detected. Antimony was found in a range of 0.2 to 4 p g/L. One sample exceeded the guideline (2μg/L) set by the Japan Environment Agency.