Hemodialysis water reuse within a circular economy approach. What can we add to current knowledge? A point of view.

The ongoing climate change and the ecological challenges call for sustainable medicine and, in our field, sustainable kidney care. Dialysis is life-saving and resource-consuming, and high water consumption is one of the main concerns. Circular water economy, meaning reuse and recycling of water, and recovering resources can help reducing emissions and enhancing resilience to climate change. Several actions are possible including reusing reverse osmosis reject water, employable for gardening, aquaponics or even simply for toilet flushing, or in sterilization settings, reusing spent dialysate, at least for toilet flushing, but with wider use if microbiologically purified, recovering thermal energy from spent dialysate, that can probably be done with simple devices, or using phosphate-rich spent dialysate for producing fertilizers, namely struvite. All these options may be economically sound, and all help reducing the final dialysis carbon footprint. There is room for open-minded innovative approaches to improve water-related sustainability in hemodialysis, ultimately reducing ecological impact and increasing availability.