Ultra-trace Element Characterization of the Central Ottawa River Basin using a Rapid, Flexible, and Low-volume ICP-MS Method

Abstract

Ultra-trace (<1 ng g -1 ) rare earth elements and yttrium (REE+Y) and high field strength element (HFSE) geochemistry of freshwater can constrain element sources, aqueous processes in hydrologic catchments, and the signature of dissolved terrestrial fluxes to the oceans. This study details an adapted method capable of quantifying ≥38 elements (including all REE+Y, Nb, Ta, Zr, Hf, Mo, W, Th, U) with minimal sample preparation in natural water aliquots as low as ≤2 mL. The method precision and accuracy are demonstrated using measurement of the National Research Council -Conseil national de recherches Canada (NRC-CNRC) river water certified reference material (CRM) SLRS-6 sampled from the Ottawa River (OR).Data from SLRS CRM are compared to those of new, filtered (<0.45 µm) stream water samples from the central Ottawa River basin (ORB), and discussed in terms of processes and geochemical signatures inherited from the highly evolved igneous/metamorphic Archean and Proterozoic bedrock in the catchment. The ORB waters have significantly LREE>HREE-enriched REE+Y patterns, small natural positive Y and Gd anomalies, and negative Eu and Ce anomalies. These REE+Y features are coherent downstream in the OR apart from amplification of Eu and Ce anomalies during REE removal/dilution. The OR samples capture a downstream decrease in sparingly soluble HFSE (Th, Nb, Ta, Zr, Hf), presumably related to their colloid-particulate removal from the dissolved load, accompanied by crustal Zr/Hf (32.5 ± 5.1) and supercrustal Nb/Ta (25.1 ± 7.7) ratios. Subcrustal Th/U (0.17-0.96) and supercrustal Mo/W (12.0-74.5) ratios in all ORB waters indicate preferential release and aqueous solubility of U>Th and Mo>W, with the latter attributed primarily to preferential W adsorption on soil or upstream aquatic (oxy)(hydr)oxide surfaces.

Development of an analytical method for accurate and precise determination of rare earth element concentrations in geological materials using an MC-ICP-MS and group separation

“…Thus, accurate, precise, and reliable methods for their determination are a pre-requisite for interpreting the geochemical implications in environmental media such as river water, groundwater, and sea water. For example, Yeghicheyan et al (2019) and Babechuk et al (2020) reported compiled data for REE concentrations of SLRS-6 (natural river water certified reference material of NRC-CNRS). In the PAAS (Post-Archean Australian Shale)-normalized REE pattern, the shape of the HREE pattern shows some differences between these elements.…”

“…In the PAAS (Post-Archean Australian Shale)-normalized REE pattern, the shape of the HREE pattern shows some differences between these elements. In particular, the HREE pattern presented by Babechuk et al (2020) indicated the possibility of a specific pattern called the REE tetrad effect ( Peppard et al, 1969 ; Masuda and Ikeuchi, 1979 ; Masuda et al, 1987 ; Kawabe et al, 1998 ; Anenburg and Williams, 2022 ). However, the HREE pattern presented by Yeghicheyan et al (2019) shows a zigzag shape rather than the REE tetrad effect.…”

“…Inductively coupled plasma quadruple mass spectrometry (ICP-QMS) is the most popular and effective instrumental technique for the determination of the REE concentrations in geological, environmental, and meteoritic materials ( Lawrence et al, 2006 ; Wu et al, 2007 ; Chung et al, 2009 ; Zhu et al, 2010 ; 2021 ; Tepe and Bau, 2015 ; Fischer and Kara, 2016 ; Pignotti et al, 2017 ; Tanaka et al, 2018 ; Babechuk et al, 2020 ; Wysocka, 2021 ). Recently, Babechuk et al (2020) reported a method for the precise and accurate determination of the REE concentrations in natural river water using ICP-QMS. The authors mentioned that the Eu concentration showed a large discrepancy compared to most of the REEs due to the BaO + interference.…”

Quantification of Re and four other trace elements (Ag, Cd, Pd, Zn) in certified reference materials and natural waters

“…, weathering, redox, cation exchange process 3–5 ) and anthropogenic activities. 6–10 Analytical advances since the 1990s, particularly development and improvements of inductively coupled plasma-mass spectrometry (ICP-MS), have sparked the growing interest in low-abundance elements. 1 However, despite the outstanding merit of this analytical technique ( e.g.…”

“…1,2 Therefore, the variations in the concentrations of these elements in the environment are commonly used to trace natural biogeochemical processes (e.g., weathering, redox, cation exchange process [3][4][5] ) and anthropogenic activities. [6][7][8][9][10] Analytical advances since the 1990s, particularly development and improvements of inductively coupled plasma-mass spectrometry (ICP-MS), have sparked the growing interest in lowabundance elements. 1 However, despite the outstanding merit of this analytical technique (e.g., low detection limits, large and linear dynamic range), spectral interferences (isobaric and polyatomic) represent the most signicant challenge to the method development workow, especially when there is a high ratio of interference-generating elements to analyte of interest.…”