Eli Newell ‘24: Recycling human waste for a more prosperous planet

What are the issues that are driving this research?  

As urban populations increase around the globe, urban agriculture is becoming more and more important. Small household gardens can contribute significantly to food security in a range of urban contexts, including in slums and other informal settlements. However, many urban soils are contaminated with heavy metals from mining or industrial legacies so an alternative is needed.

How does this kind of circularity work? How is it that urine improves soil quality?   

Plants need nutrients to construct themselves and when plants or their products are harvested and taken off the field, those nutrients are removed from the agro-ecosystem. The nitrogen and phosphorus that plants convert into amino acids, cell membranes, DNA, and ATP, for example, end up in our diets and are mostly excreted in our urine. So, it’s no surprise that our urine contains the very nutrients that our crops need to live and grow — and recycling these nutrients can hopefully offset some of the need for mined or synthetic fertilizer.

What does your day look like as an undergraduate researcher on this project? 

My work is pretty varied, which I appreciate. In the field, the work has entailed harvesting corn stalks near the Vet School’s Teaching Dairy, setting up our large experiment at Dilmun Hill farm on campus, and collecting over a thousand liters of urine. In the lab, I conduct trials of an experimental nutrient recovery technique and prepare samples for analysis. Further afield, I’ve gotten to tour some dairy farms with advanced nutrient management systems and visit the pioneering Rich Earth Institute in Brattleboro, Vermont.

While not in the field or the lab, I’ve also gotten a wealth of other practical experience such as grant writing, statistical analysis, and presenting posters at conferences. I’m really grateful to get to have such a hands-on role in so many areas of the research and surrounding work.

You recently went to Kenya with Rebecca Nelson — tell us about your visit and some of the work you were involved in. 

We went to Kisumu, Kenya which is the third largest city in Kenya and is right on Lake Victoria. 

Our trip started off with a conference, East Africa Circular Economy Workshop, which was organized by Johannes Lehmann’s lab and Rebecca Nelson’s research partner Charles Midega at Poverty and Health Integrated Solutions. The focus of this meeting was to bring together various stakeholders who are interested in advancing the circular nutrient economy, including researchers from all over the world and leaders in East Africa’s sanitation and fertilizer industries. We discussed technical barriers to implementation, regulatory needs, and much-needed standardization of protocols. 

As part of the conference, we got to attend the ribbon-cutting for Professor Midega’s Circularity Empowerment Center which features agricultural test plots, black soldier fly and poultry operations, laboratories, and a kon-tiki biochar pyrolysis unit. We also visited a sewage treatment facility, sanitation entrepreneurs (SaniWise Technologies and FreshLife), and several community-based organizations.

What made this conference so exciting is that Kenya in general and Kisumu in particular are just so far ahead with enterprises built around circularity, so I’m lucky to be able to learn from experts there who have made so much progress on this model. I am very excited to return to Kisumu this summer supported by the Laidlaw Scholars program to work with Professor Midega on geospatial analysis of waste streams and a host of other circular economy projects.

How did you get involved in research as an undergraduate student?  

My freshman year I started at Cornell with a majority of my classes online; it was hard to get to know my peers and professors over Zoom, and it was challenging to remain engaged. But Rebecca Nelson, who was teaching IARD 1100 Perspectives on International Agriculture and Rural Development, was just exceptionally engaging. I was intrigued by the fieldwork she described on improving grain storage, found her case for the circular economy and focus on soil health compelling, and was blown away by how invested she is in her students. 

When I originally reached out about working with her I was more interested in her mentorship than the research. I didn’t get the open job in her lab, which was focused on corn phenotyping, but we stayed in contact and found a different project to work on together the following year.

We wrote the Toward Sustainability Foundation grant together with Rebecca’s lab manager Ace Repka and some other collaborators for the soilless media work. We have been working together ever since with support from that grant, the Laidlaw Scholars program, and CALS Charitable Trust.

What advice do you have for undergraduates who want to study global development? 

1. Be curious. All of your peers and professors have extraordinary experience and expertise — take advantage of that and you’ll quickly find yourself both excited to learn about new things and more connected with your peers. When I came to Cornell I didn’t have any particular interest in research or in sewage, but now cherish my involvement with research here and have become passionate about sanitation.
2. Take initiative. If there’s something you want to do or someone you want to work with, make it happen. As the saying goes, if you want a seat at the table, organize the dinner – and once you find a team, prioritize contributing to your team as richly as you can. And of course you’ll be greatly advantaged by finding mentors who are committed to your learning and development. 
3. Be engaged. Whether in your classes or if you end up involved with research, engage! Don’t just go through the paces of lab work. Ask questions, understand the motivations behind the research, and contribute to the work in new ways and with purpose. Your new skills, knowledge, and relationships will expand your world.