Mass fractions of emerging elements in water, biota and polymer certified reference materials
T. Zimmermann^1,*, A. Ebeling¹, L. Hildebrandt¹, O. Klein¹, D. Wippermann¹, A. Zonderman¹, M. von der Au², J. Irrgeher³, D. Pröfrock<sup>1

1</sup> Helmholtz-Zentrum hereon, ² Federal Institute for Materials Research and Testing BAM, ³ Montanuniversität Leoben
*tristan.zimmermann@hereon.de

Reliable and accurate analysis of elemental concentrations and mass fractions in environmental samples is a prerequisite for various scientific fields such as biogeochemistry, biology and environmental science. Within this context, the scientific community requires new analytical protocols to be able to quantify more and more elements of the periodic table reliable. Therefore, the requirements for certified reference materials (CRMs) have increased drastically. Based on ICP-MS/MS, we re-analyzed various CRMs for their mass fractions/concentrations of new emerging contaminants such as rare earth elements (REE), the less studied technology-critical elements (TCEs) Ga, Ge, Nb, In and Ta and those elements which are (not yet) not part of monitoring regulations.
This presentation focusses on the quantification of less studied elements in water, biota and polymer reference materials: An online preconcentration method (seaFAST, Elemental Scientific; USA) coupled to ICP-MS/MS (8900, Agilent) enabled the quantification of 34 elements in 17 different water CRMs ranging from fresh water to seawater, including In with concentrations in the sub ng/L range [1]. Four seafood CRMs (prawn and mussel tissue) were analyzed for their mass fractions of 23 elements using ICP-MS/MS after microwave acid digestion with mass fractions in the low/sub µg/kg range for analytes like Ge, Nb, In and Ta [2]. The presence of microplastic (MP) particles in aquatic environments raised concern about possible enrichment of inorganic pollutants due to their chemical properties as well. In particular the role of metals is still poorly understood. Therefore, six polymer CRMs in the microplastic size range consisting of polyethylene, polypropylene, acrylonitrile butadiene styrene and polyvinyl chloride were analyzed for their mass fractions of 56 elements [3].
The discussed studies provide mass fractions of possible emerging contaminants and address relevant challenges in quantification of e.g. less studied TCEs, thus allowing the application of existing CRMs for method validation. Our studies showed that ‘old’ and out-of-stock CRMs are generally still suitable for use because of their far beyond shelf life stability and are of great benefit to the scientific community. Furthermore, results highlight the need for new reference materials, considering the changing requirements of the scientific community.

References
[1] A. Ebeling, T. Zimmermann, O. Klein, J. Irrgeher, D. Pröfrock, Geostandards and Geoanalytical Research, 2022, 46, 351-378.
[2] L. Hildebrandt, M. von der Au, T. Zimmermann, A. Reese, J. Ludwig, D. Pröfrock, PLoS One, 2020, 15, e0236120.
[3] D. Wippermann, A. Zonderman, T. Zimmermann, D. Pröfrock, Analytical and Bioanalytical Chemistry, 2024, 416, 2797-2807.