Wasteful Appetite
JB: This is Earth and Sky. If you see a fallen tree in the woods, you might want to take a closer look. Chances are you’ll find some white rot fungi at work.
DB: The fungus eats organic material – called lignin – which holds the wood cells together like a glue. A decayed log is soft and crumbly because white rot fungi have devoured its lignin. Scientists at the Forest Products Laboratory of the USDA Forest Service have studied the fungi’s appetite for lignin. They found that it can eat other things too – in the soil – soil pollution such as chlorinated pesticides .
JB: The treatment process involves growing the fungus on wood chips, sawdust, or cottonseed hulls. The materials are then mixed with contaminated soil. To help the fungus grow rapidly, fans circulate air through the soil, and sprinklers add enough water to keep the temperature and moisture just right.
DB: In one study, it took only about a month for over half of a sample of chlorinated pesticides to be removed from polluted soil. After two years, contamination dropped to levels clean enough to meet the standards for residential neighborhoods. The process is now beyond the demonstration phase and into commercial application.
JB: For today, that’s our show. With thanks today to the National Fish and Wildlife Foundation, we’re Byrd and Block for Earth and Sky.
The following individuals were interviewed for today’s show. Our thanks to:
Dr. Tom Jeffries
Director, Institute for Microbial and Biochemical Technology
USDA Forest Service, Forest Products Laboratory
Dr. Rich Lamar
Director of Research and Applications
Earthfax Development Corporation
More Resources:
Earthfax Engineering (parent company of Earthfax Development)
Tom Volk’s Fungi (University of Wisconsin)
The Fungus Among Us: Using White Rot Fungi to Biodegrade Environmental Pollutants (EHP Online)
White Rot Fungi (Wageningen University)
Another thing about white rot fungi – they include tasty edible mushrooms like shiitakes or oyster mushrooms.
Additional Teacher Resources
U.S. National Institute of Health, Environmental Health Perspectives: The Fungus Among Us: Use of White Rot Fungi to Biodegrade Environmental Pollutants
The recognition that environmental pollution is a worldwide threat to public health has given rise to a new, massive industry for environmental restoration. For both economic and ecological reasons, biological degradation has become an increasingly popular alternative for the treatment of hazardous wastes. Recently, white rot fungus, the only organism that degrades wood, was shown to exhibit unique biodegradation capabilities. This article explains how white rot fungi is used in the biodegradation of hazardous waste and the industry that is being created around it.
U.S. National Institute of Health, Environmental Health Issues: Mechanisms of Degradation by White Rot Fungi
This site consists of scientific reports concerning white rot fungi use as a mechanism to complete degradation of lignin and a wide variety of environmental pollutants.
