Environmental iodine speciation quantification in seawater and snow using ion exchange chromatography and UV spectrophotometric detection

• DOI: 10.1016/j.aca.2022.340700
• Publication Date: 2022-12-06T07:55:13Z
• Authors: Matthew R. Jones; Rosie Chance; Ruzica Dadic; Henna-Reetta Hannula; Rebecca May; Martyn Ward; Lucy J. Carpenter
• Keywords: Iodate; Ion chromatography

The behaviour and distribution of iodine in the environment are significant interest a range scientific disciplines, from health, as is an essential element for humans animals, to climate air quality, geochemistry. Aquatic environments reservoir iodine, where it exists low concentrations iodide, iodate dissolved organic which undergoes redox reactions. current measurement techniques species typically time-consuming, subject relatively poor precision require specialist instrumentation including those that mercury electrode. We present new method measuring species, tailored towards lower carbon waters, such seawater, rainwater snow, using ion exchange chromatography (IC) with direct ultra-violet spectrophotometric detection iodide without need sample pre-concentration. Simple chemical amendments allow quantification both addition iodide. developed IC method, takes 16 min, was applied contrasting samples encompass wide aqueous environments, Arctic sea-ice snow (low concentrations) coastal seawater (complex matrix). Linear calibrations demonstrated all matrices, gravimetrically prepared potassium standards. limit 0.12 nM based on standard deviation blank, while reproducibility <2% at >8 ∼4% <8 nM. Since there no environmental certified reference material measurements made this were compared obtained established analytical techniques; voltammetry spectrophotometry. calculated recoveries 102 ± 16% (n = 107) 116 9% 103) iodate, latter difference may be due underestimation by method. further oxidation reduction digestion establish total content, average recovery following 98 4% 92). represents simple, efficient, green, precise sensitive speciated complex matrices.