Determination of 129I in Fukushima Soil Samples by ICP-MS with an Octopole Reaction System

Abstract

A method was developed for the determination of 129

Preparation of Iodine-129 Standard Solutions for Triple Quadrupole ICP-MS

“…Repetition, sweep 10, 100 times eter injector was applied for sample introduction. 9 Plasma and carrier gases were 99.99% Ar, and reaction gas was 99.999% O 2 . The isotopic ratios of 129 I/ 127 I of the two home-made 129 I standard solutions were determined by the 127 I and 129 I concentrations using the calibration lines for 127 I and 129 I.…”

“…8 Recent developments in analytical techniques using the triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS) have allowed observation of high 129 I contents (LOD of ICP-MS/MS for the 129 I/ 127 I isotopic ratio > 10 -8 is more than six orders of magnitude higher than the LOD of AMS for the ratio). [9][10][11] The ICP-MS/MS has a compact benchtop design and is a simple system resulting that is easier to maintain than RNAA or AMS systems. The ICP-MS/MS pro-vides versatile applications by combining it with other devices such as gas or ion chromatographs and lasers and it offers high sample throughput for routine measurements.…”

“…[12][13][14] But the severe polyatomic interference of 127 IH 2 + ( 127 ID + ) cannot be entirely removed, meaning that the LOD of 129 I is restricted to 0.5 μBq mL -1 (corresponding to 129 I/ 127 I = 10 -8 ). [9][10][11] This dominant interference can be partially decreased by taking an integration time for m/z =128 prior to m/z =129. The standard reference material with certified isotopic ratio is essential to the accurate 129 I analysis by ICP-MS/MS.…”

Iodine soil dynamics and methods of measurement: a review

“…Achieving high levels of precision is challenging for 129 I, partly due to the presence of xenon impurities in the argon plasma gas ( 129 Xe + interference) in the collision cell and the potential occurrence of 127 IH2 + from samples. 52,92,96,97,115,116 Eiden, et al 117 originally investigated the effects of employing oxygen as a reaction gas to eliminate a number of interferences including: Y + , Zr + , and Xe + , achieving greatly improved sensitivity for the elements and isotopes of interest. Izmer , et al 52 employed a mixture of oxygen and helium as reaction and carrier gases in a collision cell thereby reducing 129 Xe + , and achieving a detection limit of 0.03 µg kg -1 for 129 I in soil material.…”

“…m/z = 129). 118 Polyatomic interferences such as 127 IH2 + , 97 MoO2 and 113 CdO + are then removed within the cell and only 129 I at m/z 129 then proceeds to the analytical quadrupole, crucially without the creation of new m/z 129 species in the cell. 96…”