The overall amount of metals and their variety used for technical applications has been subject to a steep increase during the past decades and is forecast to further develop. Growing metal demand for a wide range of high technology applications, including so-called ‘green’ technologies (e.g. PGM, REEs, Te) drives the economic value of these metals and the related mining efforts. For some of these metals, anthropogenic metal fluxes have outcompeted natural biogeochemical cycles, including plate tectonics (Sen & Peucker-Ehrenbrink, 2012). Dispersion and loss, inherent to their cycle between production and use (e.g. PGM from automobile catalytic converters), limit their overall recycling rates and/or end-of-life recovery is uncertain as collection and recycling still need development (e.g. REE, Yang et al. 2017). Their presence in all environmental compartments, including remote areas, makes these metals emerging contaminants and warrants systematic surveillance. However, the geochemical backgrounds, often at ultra-trace levels, and anthropogenic contributions of the critical elements are still widely under-documented, as many analytical challenges persist. Studying exposure and effects in complex environmental matrices, including natural waters or biota, at environmentally relevant contamination levels, is a prerequisite to the assessment of exposure risks.
Sen, I.S., Peucker-Ehrenbrink, B., 2012. Anthropogenic disturbance of element cycles at the Earth’s surface. Environ. Sci. Technol. 46, 8601–8609. https://doi.org/10.1021/es301261x
Yang, Y., Walton, A., Sheridan, R. et al. REE Recovery from End-of-Life NdFeB Permanent Magnet Scrap: A Critical Review. J. Sustain. Metall. 3, 122–149 (2017). https://doi.org/10.1007/s40831-016-0090-4