By Annie Lovell, MESM '22
With plastic pollution ubiquitous in our environment, a novel fungal solution may hold promise for its replacement and degradation
Photo by Matt Koller
An estimated 8.3 billion metric tons of virgin plastics have been manufactured since the 1960s--roughly equivalent to 25,000 times the weight of the Empire State Building [1]-- according to a recent study by Roland Geyer, professor of industrial ecology at UC Santa Barbara. Geyer estimates that in the past five years, roughly only 9% of that plastic was recycled, 12% was incinerated, and 79% ended up in landfills or the natural environment. [2] And with the current rate of plastic production, this amount is anticipated to double over the next 20 years.[3]
Not only does plastic take 1,000 to biodegrade, but it requires fossil fuels to produce and can release toxic chemicals. Plastics also pose significant risks to environmental and human health [4]; they are lining our waterways, circling our oceans, littering our beaches, and bio-accumulating in our food.
With limited options for remediation or recycling, researchers are looking for innovative ways to deal with this immense problem. Recent research has demonstrated the potential for innovative fungi technologies to address the plastic pollution problem by replacing conventional materials and remediating plastic waste.
Fungi have a complex root system called mycelium, which has a variety of surprising applications, thanks to its structure and low cost as a raw material.[5] For instance, in 2006, entrepreneurs Eben Bayer and Gavin McIntyre used mycelium to develop a product called MycroComposite (or “Mushroom Packaging”) that is completely plant based, requires no toxic substances or petroleum-based inputs, and is 100% biodegradable. Compared to plastic and Styrofoam, the process requires only a minimal amount of water and power. At the end of its lifecycle, this mycelium-based product naturally decomposes within 30 days, as compared to Styrofoam, which can take more than five hundred years to decompose.
Plastic packaging comprises approximately 40% of the global plastic waste stream.[6] Bayer and McIntyre started a company called Ecovative that has grown to be a world leader in bio-based packaging solutions. Their product is used across a variety of industries including agriculture, cosmetics, and electronics. Customers include Dell Computers, 3M Company, and the Department of Defense.[7] Ecovative has raised over $30 million and is valued at more than $10 million.[8]
Ecovative has developed a model for sustainable packaging, and is now exploring other applications for mycelium. For example, Ecovative researchers have engineered mycelium into a plant-based meat replacement, and an alternative for cotton and synthetics in the textile industry. Mycelium also has applications in the building industry, where insulation or other structural materials can be made out of bio-products, thus reducing the environmental footprint of homes and offices. For example, design/architecture firm redhouse studio, is creating building materials made out of recycled wood combine with mycelium to make bricks and insulation for affordable housing. These are just a few examples out of the multitude of opportunities for bio-based materials to replace conventional materials. Bio-technology is revolutionizing how we design and make products; and mycelium-based materials provide one of the most promising alternatives to traditional plastic inputs.
Some plastic products, however, are not easily replaced by bio-based technologies. Therefore, one solution for addressing waste issues is bio-remediation, which uses biological processes to break down a variety of pollutants and toxins. Fungi could also be a key solution for remediating plastic polymers at the end of their life-cycle. [9]
In 2011, a group of undergraduate students in Yale’s Department of Molecular Biophysics and Biochemistry discovered a mushroom growing on a plastic bottle while doing research in Ecuador. The team of student researchers brought the species back to the U.S. and investigated whether the fungus could digest polyurethane. After comparing a variety of organisms, the researchers concluded that there is promising potential for fungi to bio-remediate plastics and other waste streams.[10] Additionally, a team from Utrecht University discovered around 50 species of fungus that degrade different types of plastics.[11] There has been subsequently encouraging research on biodegrading fungus, including one study demonstrating the ability of mycelial fungi to remediate hazardous plasticizers in medical equipment[12] and another on fungal bio-remediation of polyester polyurethane.[9]
These are just a few examples of how fungi has the potential to address some of our most pressing plastic waste issues.[11] However, more research and development needs to be conducted before this becomes a mainstream biotechnology and truly achieves sustainable solutions for the future.
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References:
[1] Kadirgamar, Skanda. “Company Uses Mushrooms to Grow Plastic Alternatives.” JSTOR Daily. (2017).
[2] Geyer, Roland, Jenna R. Jambeck and Lara Lavender Law. “Production, use, and fate of all plastics ever made.” Sciences Advances, vol. 3, no. 7, e1700782, (2017): doi: 10.1126/sciadv.1700782.
[3] Carr, Lizzie. “Reducing Single-Use Plastic Pollution: A Unified Approach.” UN Chronicles, 19 March 2020.
[4] Thompson, Richard C et al. “Plastics, the environment and human health: current consensus and future trends.” Philosophical transactions of the Royal Society of London. Series B, Biological sciences, vol. 364,1526 (2009): 2153-66. doi:10.1098/rstb.2009.0053.
[5] Abhijith, R. Anagha Ashok, and C. R. Rejeesh. “Sustainable packaging applications from mycelium to substitute polystyrene: a review.” Materials Today: Proceedings, vol. 5.1.2 (2018) 2139-2145. https://doi.org/10.1016/j.matpr.2017.09.211.
[6] Chen, Yuan, Abhishek Kumar Awasthi, Fan Wei, Quanyin Tan, and Jinhui Li. “Single-use plastics: Production, usage, disposal and adverse impacts.” Science of the total Environment, vol 752 (2021): https://doi.org/10.1016/j.scitotenv.2020.141772.
[7] Dent, Millie. “This company is using mushrooms to reduce plastic waste.” CNN Business. (2019).
[8] Feldman, Amy. “Entrepreneur Behind Mushroom – Root Packaging Spins New Food Business Out of Ecovative to Focus on Mycelium-Based Meats. “ Forbes, (2019).
[9] Russel, Johnathan R., Jeffrey Huang, Pria Anand, Kaury Kucera, Amanda G. Sandoval, Kathleen W. Dantzler, DaShawn Hickman, Justin Jee, Farrah M. Kimovec, David Koppstein, Daniel H. Marks, Paul A. Mittermiller, Salvador Joel Núñez, Marina Santiago, Maria A. Townes, Michael Vishnevetsky, Neely E. Williams, Mario Percy Núñez Vargas, Lori-Ann Boulanger, Carol Bascom-Slack, Scott A. Strobel “Biodegradation of Polyester Polyurethane by Endrophytic Fungi.” Applied and Environmental Microbiology. 77(17)
(2011); 6076-6084. doi: 10.1128/AEM.00521-11.
[10] Fellman, Bruce. “A fungus that eats polyurethane.” Yale Alumni Magazine. 2011.
[11] Hildebrandt, Eleanor. “50 New Plastic-Eating Mushrooms Have Been Discovered in Past Two Years.” Leapsmag. (2019).
[12] Pradeep, S. and Sailas Benjamin. “Mycelial fungi completely remediate di(2-ethylhexyl)phthalate, the hazardous plasticizer in PVC blood storage bag.” Journal of Hazardous Materials, vol. 235–236, (2012): 69-77, https://doi.org/10.1016/j.jhazmat.2012.06.064.