Winfred Espejo, Cristóbal Galbán-Malagón & Gustavo Chiang
The global market for rare metals from Earth’s crust is on the rise because of their crucial role in technologies used in electronics, biomedicine and the automotive industry, for example. Most of these elements are extracted in African and South American countries, where environmental protections are often poor. We call for rigorous investigation into these metals’ environmental concentrations, biogeochemical cycles and possible risks to human and animal health.
Technology-critical elements include tantalum, gallium, germanium, indium, niobium, tellurium, thallium and other scarce metals. Despite their economic importance (see, for example, A. L. Gulley et al. Proc. Natl Acad. Sci. USA 115, 4111–4115; 2018), little is known about their environmental effects (M. Filella Earth Sci. Rev. 173, 122–140; 2017). For example, tantalum increases in aquatic organisms at each successive level of the food chain (W. Espejo et al. Environ. Sci. Technol. Lett. 5, 196–201; 2018) but it is unclear whether this accumulation poses a threat to humans and other consumers.
A better understanding of the effects of extraction and consumption of technology-critical elements will help to mitigate the risks to environmental and human health in producer countries.