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<p>Nitrogen (N) and phosphorus (P) are nutrient fertilizers that are critically important for sustained food production. In the US the vast majority of N and P enters cities in the form of food and leaves as emissions from wastewater treatment plants. These emissions enter into the environment and can cause toxic algal blooms, excessive greenhouse gas emissions, and "dead zones". Recovering nutrients at an earlier point in the cycle and repurposing them as safe fertilizers to support food production will significantly reduce the energy required for fertilizer production and ensure a safe, domestic fertilizer source for generations. This project focuses on applying proven treatment technologies in a new way to recover and repurpose nutrients from urine into fertilizer while reducing the risks associated with chemical or biological contaminants that exist in conventional fertilizers used today. This approach reduces the number of steps between wastewater production and fertilizer capture. Because perceptions toward nutrient reuse from urine could be negative, the PIs include an educational program will educate the public about the science behind the approach.</p>
<p>The vast majority of N and P consumption in human-dominated environments is derived from food. Nutrients in food that are consumed by people ultimately end up in landfills or wastewater effluents. There is a critical need to recover these nutrients and redirect them to support food production in an energy efficient and environmentally favorable manner. This project will advance energy efficient N and P recovery in the US through demonstration and deployment of technologies that produce safe urine-derived fertilizers (UDFs) via urine diversion. The PIs will use a data-informed, risk-based approach to assess the safety of UDFs. Field trials involving the growth of lettuce, carrots or hay will be conducted to determine the fate of biological (viruses, bacteria, antibiotic resistance genes) or chemical (heavy metals, trace organic) contaminants. The urine processing methods to be evaluated are a collection of technologies that have the capacity to efficiently achieve nutrient recovery, reduce fertilizer product volume, improve product aesthetics, and reduce undesirable contaminants. The PIs will extend UDF product generation through crop field trials and conduct a comprehensive monitoring campaign in support of a risk assessment. Because social attitudes toward using UDF for food may be negative, mainly due to a lack of information about risks relative to conventional methods, the PIs will integrate an assessment and communication program that involves surveys, focus groups and the development of educational materials to advance understanding about this approach. These methods are intended to advance public acceptance of urine-centered recycling technologies for sustainable food production and security. Programs that will develop a higher level of public understanding about urine-centered nutrient recycling technologies include professional training (student summer internships), unique forums for student and public learning (development of case-based learning tools; a new course; and construction of a urine diversion and UDF-processing facility for application to non-food crop at the University of Michigan botanical gardens), and information dissemination (an annual Urine Diversion and Recycling Summit and themed sessions at national conferences).</p>