Using Fungus to Break Down Plastic Waste

Project Summary

This project examined how Pestalotiopsis microspora grows and degrades cigarette butts under different conditions. The fungus grew most effectively in nutrient-rich soil, showing that soil provides strong support for its development. Growth in liquid solutions was slower but still noticeable after about 48 hours, demonstrating adaptability. High humidity reduced its activity, and the fungus tended to cling to flask surfaces rather than remain free-floating. Overall, these results show that P. microspora can survive in varied environments and has promising potential as a tool for reducing plastic waste such as cigarette butts.

Detailed Story

High school student Zaima Noaman from Sachem East High School undertook an ambitious independent research project investigating the potential of Pestalotiopsis microspora, a plastic-eating fungus discovered by Yale University in the Amazon rainforest, to address the global plastic pollution crisis. Her research was motivated by alarming statistics: since the 1960s, over 8.3 billion tons of plastic have been produced, with only 9% recycled and 27 million tons entering U.S. landfills annually. Zaima’s project focused specifically on cigarette butts, one of the world’s most littered items, with 4.5 trillion becoming litter annually worldwide. Her methodology involved growing P. microspora in liquid culture to expand the mycelia, then setting up sterile culture jars with cigarette butts (cellulose acetate), polyurethane, polystyrene, and polyethylene terephthalate to observe decomposition rates. The research revealed that P. microspora grew most effectively in nutrient-rich soil environments, both sterile and non-sterile, confirming its adaptability for waste degradation applications. In liquid solutions, growth was slower but still observable after 48 hours, demonstrating the fungus’s flexibility under different conditions. An important observation was the fungus’s tendency to cling to flask surfaces, which could inform future system designs for bioremediation applications. However, the project faced significant challenges. The growth bag containing grain and sawdust became contaminated with powdery mildew, and insects eventually invaded and consumed the material. While this represented a setback, it provided valuable insights into the importance of maintaining sterile conditions and controlling environmental factors in fungal cultivation. Zaima conducted chemical testing using established protocols to assess toxicity levels of the fungus after it had processed cigarette materials. The project demonstrated both the strong potential and real challenges of working with P. microspora in bioremediation applications. As Zaima reflected: “Completing this project gave me a real sense of hope about what small, science-based actions can do for the climate. Seeing Pestalotiopsis microspora actually grow and begin to break down cigarette butts made the problem feel less impossible — it showed that nature already has tools we can learn from and use to reduce pollution. The project also changed how I think about advocacy. Before, climate issues felt abstract and huge; after doing hands-on lab work, I feel more confident speaking up and sharing concrete ideas (like fungal bioremediation) with friends, teachers, and my community.”

Impact Statement

Zaima’s research contributed to understanding how Pestalotiopsis microspora could potentially be scaled for practical waste management applications. Her work demonstrated the fungus’s ability to survive in varied environments while processing toxic materials like cigarette filters. The project showed that even individual student research can contribute meaningful data to the field of environmental biotechnology and bioremediation. The research findings highlighted both the promise of biological solutions to plastic pollution and the practical challenges of implementing such systems, providing valuable baseline data for future scaled applications. The project had significant personal impact, transforming Zaima’s perspective on climate advocacy from feeling overwhelmed by abstract problems to gaining confidence in science-based solutions and environmental communication.