Can a fungus help clean up lead-contaminated soil?

BUFFALO, N.Y. — Urban gardening is on the rise in cities across America. But in so-called legacy cities like Buffalo, where lead and other contaminants have seeped into the soil over decades of heavy industry, it can be extremely dangerous to grow food.

Help, however, may be on the way in the form of a fungus.

Researchers from the University at Buffalo are leading a project funded by the U.S. Department of Housing and Urban Development (HUD) that aims to shed light on the merits of mycelium-based soil remediation, while educating the public about the potential hazards of lead-contaminated soil.

The work, which includes community partners from the City of Buffalo and Grassroots Gardens of WNY, as well as researchers from the University of Louisiana at Lafayette, is being funded through a three-year, $659,499 HUD grant.

Mycelium is the branched, thread-like root system – the vegetative body of fungi from which mushrooms form.

“Mycelium has several features that help remediate lead or other toxicants. Specifically, mycelium is a fibrous network, where the cell wall of each fiber contains several proteins and enzymes that actively interact with heavy metals and other organic pollutants,” says Katarzyna Kordas, PhD, associate professor of epidemiology and environmental health in UB’s School of Public Health and Health Professions and principal investigator on the project. Kordas also co-directs the Community for Global Health Equity at UB.

Live mycelium has shown tremendous promise as a solution to cleaning up environmental pollutants in soil, but that requires expertise in growing and maintaining mycelium and mushrooms.

“The unique aspect of our work is that we’re using dried mycelium membranes, or sheets, that are pre-manufactured and therefore offer much more uniform conditions in terms of porosity, texture, strength and resilience,” Kordas says.

“This novel biomaterial generates sustainable and highly resilient membranes that can be easily deployed in the soil and later be recovered,” said Prathima Nalam, PhD, assistant professor of materials design and innovation in UB’s School of Engineering and Applied Sciences. Nalam has been investigating the properties of mycelium and its potential to clean up soils and water for the past five years.

“Because we are working with dried mycelium, we are focusing on adsorption, or the ability of mycelium cell walls to bind and hold on to lead,” added Nalam. “The second mechanism we’re testing is biomineralization, or the precipitation of lead minerals around the mycelium fibers.”

As a first step, the team will conduct lab experiments to better understand the parameters that influence these mechanisms. They’ll also perform electron microscopy imaging of the mycelium membranes to understand how the structural nature of the network of fibers can support lead remediation.

“Having a better understanding of these factors will help us work with the membrane when we proceed to work with soil,” Kordas explained.

The team will also speak with gardeners and other potential users of mycelium membranes to understand their willingness to use the material, and will conduct analyses of local policies to understand how mycelium could work alongside existing lead remediation approaches.

Lead contamination of residential and gardening soils contributes to the risk of lead poisoning among children and adults, which could result in long-term consequences for their health. These include effects on growth and development of children and on cardiovascular health in adults, the researchers note.

To address lead poisoning, former industrial cities like Buffalo — where the soil often contains lead from industrial sources, including deteriorated lead-based paint — need a wide range of lead remediation, educational and policy approaches at their disposal to complement ongoing efforts.

There are also cultural implications. In Buffalo, for instance, the city’s population has increased over the past decade due primarily to an influx of refugees, many of whom, following traditions, set up home gardens, unaware of the potentially toxic conditions in the soil.

Children can be exposed to lead through soil during play or through the consumption of vegetables grown in contaminated soil.

Recent efforts to address childhood lead poisoning in Buffalo have employed regular blood lead testing, and a suite of housing-related policies are underway. The UB-led research team, however, is now looking to address soil hazards in an innovative, cost-effective way, which excites project partner Jeanette Koncikowski, executive director of Grassroots Gardens of WNY.

“The potential impact of this project is huge,” Koncikowski says. “It is currently not safe to grow food in-ground anywhere in the city that hasn’t been tested or remediated, due to lead and other heavy metal contamination, which is why you’ll find mounded beds or raised beds in all of our member-gardens. We are excited to see how this experimental medium will work in the field and whether it will offer a future in which Buffalo’s urban agriculture can finally move to a permaculture model of in-ground growing without the expense associated with soil remediation.”

Additional researchers who are part of the project include Emmanuel Frimpong Boamah, PhD, assistant professor of urban and regional planning in the School of Architecture and Planning, and Olga Wodo, PhD, associate professor of materials design and innovation in the School of Engineering and Applied Sciences, both from UB; and Anna Paltseva, PhD, of the University of Louisiana at Lafayette.