Transitioning to green energy requires more sustainable rare earth element (REE) production. The current REE supply relies on energy- and chemical-intensive mining, prompting interest in alternative sources like phosphogypsum (PG) waste. However, using conventional solvent extraction to recover REEs in PG is inefficient and environmentally burdensome. This study proposes a treatment train for REE recovery from PG, featuring a bioinspired adsorptive separation, and evaluates its environmental and economic performance using a probabilistic sustainability framework that integrates life cycle assessment (LCA) and techno-economic analysis (TEA). Results show the system achieves an internal rate of return (IRR) above 15% in 87% of simulations, suggesting strong profitability potential. Environmentally, it outperforms conventional REE mining and PG treatment in ecosystem quality and resource depletion but shows higher human health impacts. Scenario analysis reveals profitability at processing capacities over 100 000 kg·h–1 for PG with REE content above 0.5 wt %. However, more dilute sources (0.02–0.1 wt %) are not viable under current conditions due to acid and neutralization costs. This study offers the first in-depth sustainability assessment of REE recovery from PG waste and highlights key areas for future process development to improve access to low-grade sources and enhance environmental outcomes.

Rare earth (RE) elements are critical materials that underpin many modern technologies, particularly in the clean energy industry. Despite their importance, these vital resources are difficult to obtain due to the presence of numerous metals and radioactive contaminants, such as thorium, that are present in RE ores. Current processing methods, which are dominated by homogeneous solvent extraction, are inefficient and produce substantial hazardous waste. In this work, we describe an alternative strategy to separate thorium from REs through metal–organic framework (MOF) crystallization. Starting from a mixture of thorium and rare earth ions in solution, we utilize the simple carboxylate ligand trimesic acid to selectively crystallize a novel thorium MOF, NU-2500, leaving the remaining rare earth ions in solution. By leveraging the increased oxophilicity of Th(iv) compared to RE(iii) ions, we observe the exclusive formation of the thermodynamically preferred Th-MOF product. This valence-selective crystallization strategy occurs rapidly (within 30 minutes) at mild temperatures (80 °C) with an environmentally-friendly ethanol/water solvent system to produce phase-pure NU-2500 containing >98% molar fraction of thorium. Sequestering the radioactive Th(iv) ions within a solid framework enables facile separation of REs through simple filtration. We demonstrate that our selective crystallization platform retains its high selectivity for Th crystallization even at low initial Th concentrations and in complex mixtures with multiple different REs. We anticipate that further insights into the kinetics and thermodynamics of MOF crystallization can be applied to additional challenging industrial separations.

Despite steady progress in the development and promotion of the circular economy as a model, an overwhelming proportion of technological devices discarded by the Global North still finds its way to the Global South, where technology-related environmental health problems start from the predation of resources and continue all the way to recycling and disposal. We reviewed literature on TCEs in sub-Saharan Africa (SSA), focussing on: the sources and levels of environmental pollution; the extent of human exposure to these substances; their role in the aetiology of human diseases; their effects on the environment. Our review shows that even minor and often neglected technology-critical elements (TCEs), like rare earth elements (REEs) and platinum group elements (PGEs), reveal the environmental damage and detrimental health effects caused by the massive mining of raw materials, exacerbated by improper disposal of e-waste (from dumping to improper recycling and open burning). We draw attention of local research on knowledge gaps such as workable safer methods for TCE recovery from end-of-life products, secondary materials and e-waste, environmental bioremediation and human detoxification. The technical and political shortcomings in the management of TCEs in SSA is all the more alarming against the background of unfavourable determinants of health and a resulting higher susceptibility to diseases, especially among children who work in mines and e-waste recycling sites or who reside in dumping sites.This paper demonstrates, for the first time, that the role of unjust North-South dynamics is evident even in the environmental levels of minor trace elements and that the premise underlying attempts to solve the problem of e-waste dumped in Africa through recycling and disposal technology is in fact misleading. The influx of foreign electrical and electronic equipments should be controlled and limited by clearly defining what is a 'useful' second-hand device and what is e-waste; risks arising from device components or processing by-products should be managed differently, and scientific uncertainty and One Health thinking should be incorporated in risk assessment.

acid. Another example is in rare earth-mining where ores such as monazite may contain thorium and its decay products which are subsequently found enriched Naturally occurring radioactive materials (NORM) and technologically enhanced naturally occurring radioactive materials (TENORM) consist of materials, usually industrial wastes or by-products enriched with radioactive elements found in the environment, such as uranium, thorium and potassium-40 (a long-lived beta emitter that is part of natural potassium on earth) and any of the products of the dec Natural radioactive elements are present in very low concentrations in Earth's crust, and are brought to the surface through human activities such as oil and gas exploration, drilling for geothermal energy or mining, and through natural processes like leakage of radon gas to the atmosphere or through dissolution in ground water. Another example of TENORM is coal ash produced from coal burning in power plants. If radioactivity is much higher than background level,… Type…

Rare earth elements (REEs) are increasingly released into the environment due to intensive mining, industrial processing, and expanding technological applications, resulting in widespread human exposure. Within the respiratory exposome framework, REEs have increasingly been recognized as a potentially important class of airborne contaminants. Fine and ultrafine REE-containing particles can penetrate deeply into the distal lung, where they exhibit high biopersistence and limited clearance. Epidemiological evidence from mining and industrial regions suggests that elevated internal REE burdens may be associated with increased prevalence of respiratory symptoms and chronic lung diseases, including bronchitis and interstitial lung disease. Toxicokinetic and experimental studies provide mechanistic support, demonstrating that inhaled REEs preferentially deposit in the alveolar region, interact with epithelial and immune cells, and may translocate into systemic circulation. At the molecular level, REEs have been shown to induce oxidative stress, immune and inflammatory dysregulation, and calcium homeostasis imbalance in experimental models, thereby promoting tissue injury and remodeling. These processes may contribute to a progressive pathological continuum from persistent inflammation to fibrosis and, potentially, tumorigenesis. Notably, exposure characteristics-including particle physicochemical properties, dose, co-exposure scenarios, and host susceptibility-critically shape health outcomes in real-world settings. Despite accumulating evidence, key uncertainties remain regarding human-relevant exposure thresholds, long-term dose-response relationships, and validated biomarkers of effect. Current knowledge is still largely derived from experimental models, with limited integration into population-based risk assessment. Overall, this review uses a structured literature search and narrative synthesis approach to integrate environmental exposure pathways, toxicokinetic characteristics, and mechanistic evidence within an exposome-oriented framework. It highlights that REEs represent emerging inhalation hazards with the potential to contribute to the burden of chronic respiratory diseases, underscoring the need for improved exposure assessment, biomonitoring strategies, and evidence-based public health interventions.

<h4>Background</h4>Rising demand for rare earth elements (REEs) and the severe environmental impact of conventional extraction from phosphate minerals (monazite, apatite) have intensified the search for green alternatives. Microbial bioleaching offers a low-energy, low-waste, and a sustainable biotechnological alternative by exploiting the ability of fungi and bacteria to generate organic acids, siderophores, reducing agents, and other metabolites that solubilize REEs. Although interest in REE bioleaching has increased, a biotechnology-focused synthesis of microbial mechanisms, metabolic constraints, and process determinants specific to phosphate matrices remains limited.<h4>Methods</h4>A PRISMA-guided systematic review was conducted. Scopus, Web of Science, PubMed, and Google Scholar and other major databases were searched to identify peer-reviewed studies reporting microbial bioleaching of REEs from phosphate minerals. From 443 identified records, 25 studies met the inclusion criteria after screening and eligibility assessment. These studies were evaluated based on microbial species, metabolic mechanisms, culture conditions, mineral substrates, and REE solubilization performance.<h4>Results</h4>Fungal species, particularly Aspergillus, Penicillium and Paecilomyces demonstrated the highest REE mobilization efficiencies through intensive production of citric, oxalic, and gluconic acids, along with phosphatase activity. Bacterial strains, including Acidithiobacillus, Bacillus, Pantoea, Burkholderia, Pseudomonas, and Klebsiella contributed complementary mechanisms such as proton extrusion, siderophore secretion, and Fe(III) / Fe(II) redox cycling. Bioleaching performance was strongly influenced by media composition, carbon source, nitrogen assimilation, pH evolution, mineralogy of the phosphate substrate, pulp density, and particle size. Across studies, the lack of standardized conditions limited direct comparability, but organic acid dominated pathways consistently produced the most robust REE solubilization.<h4>Conclusions</h4>Microbial bioleaching is a promising biotechnological platform for REE recovery from phosphate minerals, driven by metabolically diverse acidogenic, chelating, enzymatic, and redox mechanisms. However, advancements remain constrained by heterogeneous methodologies, limited integration of mechanistic studies, and minimal use of engineered strains or controlled bioreactor systems. Future progress requires standardized experimental frameworks, improved mechanistic understanding of organism-specific roles, and rational design of optimized microbial systems. This review offers a biotechnology-centered foundation to guide next-generation research on sustainable REE mobilization from phosphate resources.