UBC’s MycoToilet: World’s first mushroom-powered waterless toilet that turns human waste into compost in 6 weeks |

Somewhere between the University of British Columbia’s botanical gardens and forest trails lies a cedar-clad timber building with a green roof, skylight-lit interior and wheelchair-accessible ramps. Smells like forest. It looks like a well thought out building. Hidden within its back wall is something that has never been used in a public restroom before: a cubicle lined with live mushroom mycelium that absorbs odors, speeds decomposition, and turns human waste into usable compost without requiring a drop of water, a single gram of chemical input, or the need for any plumbing. this Michael toiletdeveloped by researchers in UBC’s School of Architecture and Landscape Architecture and the Department of Microbiology and Immunology, will launch in September 2025 at the UBC Botanic Gardens. It’s the first installation of its kind in the world, and it’s trying to solve a problem much larger than any single campus installation.

Global health crisis makes mushroom-powered waterless technology so urgent

The scale of the hygiene problems that technology like MycoToilet aims to solve is truly astounding. one 2024 Review published in ISME Magazine More than 2 billion people lack access to adequate sanitation, Oxford academic finds UBC Campus as Living Laboratory Project Introduction MycoToilet has a budget of 2.3 billion, of which 450 million people are completely restricted from open defecation. Untreated human waste is a leading cause of preventable disease and child death in developing countries.Mainstream solutions all have serious limitations. Centralized wastewater treatment is energy-intensive, water-intensive, and requires significant infrastructure investment that many urban and rural communities cannot afford. Chemical toilets, the most commonly used portable devices in parks, construction sites and event venues, rely on formaldehyde and other toxic chemicals, requiring the waste to be treated as hazardous materials during the disposal phase. Traditional composting toilets are in principle a cleaner alternative, but have historically had odor issues, inconsistent decomposition and operational reputation issues that have led to municipalities being reluctant to adopt them on a large scale.

What is mycelium and how fungi break down human waste faster than standard compost

MycoToilet’s core innovation is to replace the standard composting process with one powered by fungal mycelium, the dense network of thread-like roots that form the vegetative body of the mushroom, distinct from the fruiting body that appears above ground. according to aA review of mycoremediation published in Applied Science 2023Fungi produce powerful extracellular enzymes capable of breaking down complex organic compounds, including lignocellulosic biomass, hydrocarbons and biological waste, into simpler compounds that can then be further processed by microbial communities. This enzymatic ability makes mycelium particularly suitable for breaking down human waste.“Fungi are very good at breaking down biomass, including human and animal waste,” Steven Hallam, Ph.D., professor in UBC’s Department of Microbiology and Immunology, said in an official UBC statement. “They produce enzymes that convert materials into simpler compounds while supporting microbial communities that accelerate decomposition. No added water, electricity or chemicals required. “A UBC Living Lab project abstract states that mycelium-based decomposition of harmful pathogens takes about half the time of a traditional composting toilet, which represents a significant operational advantage for a system designed to be maintained on a minimum schedule. Laboratory tests of mycelium liners show they can remove more than 90% of odor-causing compounds, addressing the biggest practical barrier to the adoption of composting toilets in public and community settings.

How the MycoToilet system separates waste, eliminates odors and produces fertilizer and compost

MycoToilet operates through a separation-first design. Liquid and solid waste are separated at the deposition point, and solid waste is directed into a mycelium-lined compost chamber at the rear of the structure. The communities of fungi and thermophilic microorganisms they support then break down the solid material aerobically (that is, in the presence of oxygen), preventing the anaerobic conditions that produce odor and methane that plague poorly designed composting systems.Low-powered fans keep air flowing through the ventilated cedar structure, and a skylight design supports passive temperature regulation. The four maintenance visits the system requires each year are intentional rather than reactive, a design choice that project leader Joseph Dahmen, an associate professor in UBC’s School of Architecture and Landscape Architecture, describes as intentional: “We’ve removed the uncertainty that might have scared municipalities away from composting toilets and solved that problem: schedules are set, ventilation is integrated, everything works the way it should.“When fully operational, MycoToilet is expected to produce approximately 600 liters of nutrient-rich soil compost and 2,000 liters of liquid fertilizer per year. Nutrient recovery rates are remarkable: Research published in ISME Magazine Research has found that well-managed composting of human waste can recycle up to 91% of the nitrogen, 83% of the phosphorus and 59% of the potassium contained in the waste, which could reduce reliance on synthetic fertilizers if returned to agricultural soils.

Architecture and materials behind UBC Botanic Gardens’ MycoToilet design

The physical structure of MycoToilet is as well thought out as its biological system. Prefabricated wooden planks form the main structure, with a cedar exterior that is naturally resistant to rot and charred using the traditional Japanese technique of “shou sugi ban” to give it additional antimicrobial properties. Green roofs support native plants and native wildlife habitat. The interior, which combines wood and stainless steel finishes with odor-absorbing mycelium compartments, was designed by Damen to replace the look and smell typically associated with composting toilets with something closer to a forest sanctuary.“We wanted to transform what everyone knows as an everyday experience into an enjoyable experience that reminds us of our connection to ecological cycles,” Damen said. The structure blends into the forested environment of the Arboretum, is fully wheelchair accessible via ramps, and features modular and repositionable design features that have immediate implications for deployment in parks, remote communities and areas without pipeline infrastructure.

Six-week pilot testing and future research will determine expansion of MycoToilet

The six-week pilot, which begins in late September 2025, is testing MycoToilet under real-world usage conditions, with researchers from SALA and the Department of Microbiology and Immunology monitoring how fungi and microbial communities interact as the system processes large volumes of actual human waste.If the pilot demonstrates consistent performance, the system’s self-contained, chemically clean and low-maintenance nature will make it a reliable alternative to chemical toilets in parks and public spaces, and could be a meaningful sanitation option for communities that need it most. A toilet that requires no water, no chemicals, no sewage connections, only four maintenance times per year, while converting waste into agricultural inputs, has a fundamentally different proposition than any toilet currently being deployed at scale. Whether it can reach that scale is a question that must be answered by current research.