The increasing demand for rare earth elements (REEs), essential for modern technologies, is accompanied by significant environmental impacts caused by conventional mining activities, which compromise natural capital and the associated ecosystem services such as water quality and biodiversity. At the same time, the growing production of electronic waste (e-waste) represents a potential source of critical metals but also a widespread source of contamination, particularly through the dispersion of heavy metals in water bodies.  

This study proposes the use of the extremophilic microalga Galdieria daedala as a biotechnological filter for treating contaminated liquid matrices, especially effluents from e-waste recycling and acidic industrial processes. Thanks to its ability to survive in extreme conditions and selectively absorb metal ions, Galdieria enables the effective recovery of REEs while simultaneously reducing the pollutant load in waters, improving water quality and contributing to the protection of aquatic ecosystems. This integrated system acts as a regenerative biological filter, capable of removing heavy and toxic metals, mitigating negative environmental impacts and supporting the conservation of natural capital.

Moreover, this approach can be incorporated into environmental assessment frameworks that also account for the ecological benefits it provides, such as water purification and pollution reduction in degraded environments. Therefore, the project represents a concrete example of biotechnology applied to the sustainable management of critical resources and ecosystem regeneration, supporting an ecological transition that combines innovation, conservation, and sustainable economic development.