case study: Public Attitudes About Human Derived Fertilizers

Human Derived Fertilizer Market Evaluation & Field Tests


How might farmers and the public respond to the practice of using human derived fertilizer to grow produce?

The public is much more accepting of urine fertilized produce than regulators assumed and feared

Urine as fertilizer

My entree into sustainable sanitation, with Nature Commode, was built on my interest in nutrient cycling and the embedded value in human urine. Equivalent in nutrients to synthetic fertilizers, it could be managed as a resource, instead of a waste. My personal interest was in urine’s application on food based crops but knew I would need to understand public and farmers’ attitudes prior to pursuing the commercialization of this unique fertilizer.

I secured funding from Western Sustainable Agriculture and Research Foundation, a USDA supported entity that advances innovation in agriculture. Funds were allocated to two projects.

One, I engaged small farmers in the region to test urine as a fertilizer in comparison to organic fertilizers such a chicken manure. Four farms participated in growing small plots of corn and testing urine against the fertilizing methods the farmers typically employed. The results revealed some challenges with the utilization of a liquid based fertilizer but, overall, proved promising for urine.

Urine Case Study image

To better under urine’s opportunities and constraints, from a grower’s perspective, owners of small and medium sized farms were surveyed.

• 32 Oregon farmers responded to an online survey
• 41 surveys were completed at Oregon State University’s 2015 Small Farms Conference
• 68% said they are in need of a fast-acting nitrogen fertilizer seasonally
• 66% own the equipment to distribute liquid fertilizer.

 64% responded yes to the question that if urine was treated according to a standardized method, should it be allowed as a fertilizer on certified organic crops

The second project focused on public attitudes. I contracted DHM Consulting, a preeminent consulting firm in Portland. With their guidance, I developed the content for the focus groups. Consumer Opinion Services recruited the participants. The request was for a diverse mix of ages, income and education, with a political leaning toward moderate/conservative. The only information the participants received was that the topic would be about natural fertilizer.

Each question was first posed as a written exercise, to be completed independently, followed by a group discussion. This structure was intended to reveal personal perspectives prior to influence from the others in the group.

To verify these opinions, and as an outreach tool, 177 in person and online surveys were also conducted. The results of both were quite similar, with positive support for the use of human urine as a fertilizer, even on crops for human consumption.

Overall, the consensus was that urine fertilizer was sensible and acceptable. Many could understand the benefits urine could provide, and appreciated a natural alternative to synthetic fertilizers. The fact that the participants self-identified as moderate or conservative reveals that urine based fertilizers could be appreciated by mainstream consumers.

I developed an educational brochure and presentation on the benefits of human derived fertilizers. I worked with a graphic designer to develop a short animation on the benefits of nutrient cycling.