Comparative analysis of sea salt species in snow samples from Svalbard using ICP-QMS and IC techniques

Abstract

Inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) and ion chromatography (IC) paired with either a conductivity detector (IC-CD) or single quadrupole mass spectrometer (IC-MS) are essential techniques in environmental analysis. Previous research has demonstrated robust agreement when applying these methods to Antarctic ice cores and snow samples. However, the high concentrations of sea spray and mineral dust found in Arctic snow samples pose distinct challenges, that might impact the accuracy and precision of measurements, despite the existing efforts to minimise matrix effects. In particular, the higher amount of dust in the Arctic snow/ice samples could present an additional source for insoluble elements typically found in sea spray that is insoluble and thus undetectable by IC, causing a divergency between the results obtained from the two techniques. Therefore, it is crucial to comprehend how these factors influence the efficacy of ICP-QMS and IC techniques in polar research. This study provides a detailed comparison of these methods in quantifying sea salt species – sodium (Na), potassium (K), magnesium (Mg), and bromine (Br) – in surface snow samples collected at Svalbard. By cross-validating IC and ICP-QMS for these tracers, the study assesses each method's accuracy, sensitivity, and precision, providing valuable insights into their optimal application in polar research and climate studies.