Tellurium Speciation via Frontal Chromatography ICP-MS: An Innovative and Effective Approach for the Ultratrace Detection in Environmental Matrices

Abstract The increasing use of tellurium (Te) in electronics and renewable energy technologies has elevated its environmental concentration, posing ecological and health risks. This study addresses the critical need for effective methods to speciate Te by focusing on its two primary redox states—tellurite (Te(IV)) and tellurate (Te(VI))—which differ in reactivity, mobility, and toxicity. Existing analytical methods for Te speciation are often limited in sensitivity and can’t simultaneously determine both species. In response, we present a novel, rapid, practical, and highly sensitive approach for determining Te(IV) and Te(VI) using frontal chromatography coupled with inductively coupled plasma mass spectrometry (FC-ICP-MS). Multivariate optimization of chromatographic conditions, along with the exploitation of the “carbon effect” and careful isotope selection, yield detection limits of 1.0 ng/L for Te(IV) and 1.3 ng/L for Te(VI) with a total analysis time of five minutes. Acidification with nitric acid is the only sample pretreatment required. Applied to natural waters, sediments, and soils, the method demonstrates high accuracy, superior sensitivity, greenness, and practicality, compared to state-of-the-art methodologies, offering an alternative and advantageous solution for routine Te speciation analysis across various environmental compartments.