The ongoing race between emerging contaminants and analytical chemistry: New approaches in ICP-MS/MS and determination of technology-critical elements in marine biota reference materials

Technology-critical elements (TCEs) show a dramatic increase in industrial applications in recent years and decades. Technological applications in our everyday life have come a long way in the number of used elements, with almost every element of the periodic table today. Based on the fact that many TCEs are recycled only to a very small extent or not at all, TCEs may become contaminants of high concern in the future.

Yet, important knowledge gaps remain about the environmental behavior of TCEs and their uptake into the food chain. Therefore, tools are needed that enable a sound and reliable determination of TCEs in order to further understand their impact on the environment. We present the advantages of N₂O as a reaction gas for inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) for the multi elemental analysis of the majority of TCEs (e.g.: Ga, Ge, In and Ta). Thus, allowing the determination with LODs between 0.00023 µg L^-1 (Eu) and 0.13 µg L^-1 (Te). In addition, we used a microwave assisted closed vessel digestion to determine non-certified TCE mass fractions within four commonly used reference materials in the field of environmental marine chemistry: NIST 2976 (mussel tissue), NIST 1566a (oyster tissue), BCR 668 (mussel tissue) and NCS ZC73034 (prawn). Presenting mass fractions for Ga (11 µg kg^-1 ± 9 µg kg^-1 - 63 µg kg^-1 ± 8 µg kg^-1) and In (0.39 µg kg^-1 ± 0.29 µg kg^-1 – 0.7 µg kg^-1 ± 0.7 µg kg^-1) as non-certified elements within all of these CRMs.