Hydride Generation Atomic Absorption Determination of Tellurium Species in Environmental Samples with in Situ Concentration in a Graphite Furnace

Abstract

An ultrasensitive method is described for the measurement of picogram amounts of tellurium species in environmental samples. The method involves selective Te(IV) reduction by sodium borohydride to hydrogen telluride, trapping in situ in a modified graphite furnace, and subsequent atomic absorption detection. The total amount of Te is determined after Te(VI) reduction to Te(IV) by boiling in hydrochloric acid. The difference between the amounts of Te(IV) and total-Te is taken as the amount of Te(VI). The absolute detection limit ranges from 2 to 4pg of tellurium. The precision of the method is 5.1% for 20pg and 2.5% for 200pg of tellurium. Analytical results are presented for natural waters, aerosol particles, geological and biological materials.