Cigarette filters are the most commonly littered waste product in the world. Last year, nearly 1.7 billion pounds of cigarette filters were thrown into the globe’s landfills and ecosystems. That’s roughly 4.5 trillion cigarette butts littered each year! In the US alone, an estimated 135 million pounds of cigarette butts are thrown away annually.
Cigarette filters are made from a type of plastic called cellulose acetate. As cellulose acetate does not readily biodegrade, cigarette litter can persist in the environment for 10-15 years or longer before it begins to break down. The filters that aren’t thrown into the streets and parks of the world find their way into landfills where they slowly leach toxic chemicals and heavy metals into ground water systems. Fortunately, fungi may provide a solution to this global issue.
As discussed in the Radical Mycology article, Fungi and The Plastics Problem, it has long been known that fungi can degrade various forms of plastic. However, a large-scale, real-world application of this ability has never been explored to any real depth. This may have been due to a variety of factors, one of which being that the chemical composition of many plastics is too complex for many fungi to readily digest. The plastic that composes cigarette filters, however, is of a rather simple composition and thus allows some common fungi to easily digest it.
Cellulose is the structural component in plant cell walls and is also one of the most accessible nutrient sources that fungi degrade in the natural world. Fungi use digestive enzymes to break down cellulose into simple sugars, which are then metabolized by the fungus. As the cellulose acetate that comprises cigarette filters is nothing more than a modified form of plant cellulose, it turns out that some fungi can break down this industrial plastic waste product.
As Peter of the Radical Mycology project demonstrates in the video below, fungi can not only be trained to digest used cigarette filters but possibly the toxic chemicals that they harbor as well. The methodology Peter used to accomplish this goal was based on an understanding of the skills needed to “train” a fungus to digest a foreign substance. Simply put, the mushroom cultivator must slowly introduce a new food source to a fungus so that the fungus can first determine and then produce the correct enzymes necessary to digest the novel substrate. The same concepts that Peter introduces in this video can be applied to a range of toxins and industrial chemicals, such as petroleum products, dioxins, dyes, and munitions. This is a concept known as fungal remediation. In recent years, skills such as these were coveted techniques used by professional mycologists and bioremediation firms. However, as the global grassroots bioremediation community has continued to grow in the last few years, these techniques have become increasingly more available to the common cultivator.
Skills such as this will be explored in-depth in the Radical Mycology Book. If you would like to learn more advanced mycological skills for reducing your pollution impact and to help clean up the environment, please consider backing the Radical Mycology Book Indiegogo campaign.