Determination of Selenium and Tellurium in Air by Atomic-Absorption Spectrometry

Elemental selenium and tellurium, and gaseous inorganic forms of Se(IV), Se(VI), Te(IV) and Te(VI) have been determined after their adsorption on gold-coated beads. After leaching, with water and dilute hydrochloric and nitric acids, the different chemical species in each acid fraction were separated with an anion-exchange resin (Bio-Rad AG-1X8) and a cation-exchange resin (Amberlite IR-120 Plus) by varying the acidity of the leaching agent. Subsequent analysis was by graphite-fumace atomic-absorption spectrometry. The lower detection limit for Se and Te was 0.03 ng/M3 with a precision of ± 5%. The average amounts of selenium in interior and exterior air samples were about 4.73 and 1.93 ng/m3 respectively. For tellurium the corresponding values were about 0.78 and 0.24 ng/m3