Scientists are exploring ways to transform human urine from a waste product into a high-value agricultural resource to combat fertilizer shortages and wastewater issues, according to xataka.com.mx.
Researchers at the University of Surrey in England have successfully repurposed the liquid by concentrating its essential minerals. The process creates a fluid rich in nitrogen, phosphorus, and potassium, acting as a nutrient-dense fertilizer for plants.
Using a low-energy forward osmosis process, the team avoided the heavy resource consumption typical of conventional wastewater treatment technologies. Lead author Siddharth Gadkari described human urine as a "sort of paradox," noting that it contains the exact nutrients required for modern agriculture.
This method aims to promote more sustainable global water and nutrient management. By reducing reliance on synthetic fertilizers, the process could lower the massive energy and resource costs associated with their production.
Scalability and safety challenges
Research from the Universitat Autònoma de Barcelona examined plant life cycles across three scenarios: an artificial wetland (S1), a laboratory-scale aerobic reactor for nitrogen recovery, and a centralized wastewater treatment plant. The study found that human urine serves as a renewable nitrogen source that can replace synthetic options while reducing eutrophication and saving water.
The findings suggest high potential for integration into urban agriculture within buildings. However, the study noted that at small scales, such as individual homes or apartments, the process currently consumes high amounts of energy and carries risks of ecotoxicity and climate impact.
Scottish specialist Elizabeth Waddington, aligning with World Health Organization (WHO) findings, confirmed that urine provides essential nitrogen for leaf growth, phosphorus for root and fruit development, and potassium for water regulation and disease resistance. These benefits were measured against standard commercial fertilizers.
Despite the nutrient potential, the resource requires careful management. Excess nitrogen can damage plant roots and foliage, and the presence of salts, pathogens, or pharmaceutical residues poses environmental risks.
The WHO advises against using undiluted urine or applying it directly to edible fruits. To prevent disease transmission, the organization recommends applying the liquid only to the roots of plants.
