Greta Gerwig’s Barbie and Christopher Nolan’s Oppenheimer hit theaters on Friday, July 21st--and while the two blockbusters had little in common--the Internet fused them together into a single cinematic sensation known as “Barbenheimer,” resulting in a variety of silly memes melding the famed plastic dolls with the development of the atomic bomb. The films celebrate the proliferation of two modern marvels born of nonrenewable resources: plastic and nuclear power. Their use has deep implications for our present and future health, and among the vast diversity of life on Earth, fungi alone may possess the unique ability to address and lessen their respective negative impacts. In this article, we identify the hazards and opportunities posed by plastic waste and nuclear radiation and explore ways fungi might be beneficial in remediating both.
Barbie: Not so Fantastic Plastic
Plastic waste is a global problem, with 85 percent of the 300 to 400 million tons produced annually ending up in landfills or the ocean, and is expected to increase over time. Plastic is made from planet-warming fossil fuels like crude oil and is designed to last much longer than a single human lifetime, often up to 500 years or more, and was never intended to be recycled. We know that microplastics are everywhere, from the deepest oceans to the tallest mountains and even in our blood. When incorporated into our bodies, plastic and its degradation products are toxic to human health. According to one comprehensive study measuring the toxicity of 34 everyday plastic products, seventy-four percent were toxic in some way, and a recent study found that numerous harmful agents are released from plastic waste over its long lifetime.
Unfortunately, Barbie dolls contribute to plastic waste, with 60 to 90 million sold annually and an estimated 80% of these ending up in landfills, incinerators, or the ocean. Dolls made prior to the 1990s can be especially bad for human health, as they are made of polyvinyl chloride (PVC) and phthalate-based plasticisers which have been linked to asthma, metabolic disorders, obesity, and other health problems. While Barbie’s parent company Mattel launched a line of 90% recycled ocean-bound plastic dolls in 2021 and pledged to make all its products 100% recycled, recyclable or bio-based plastic by 2030, the majority of new dolls are still made from virgin plastic. You may have heard the news that Mattel would be phasing out all plastic in their products by 2030 and had launched a new line of decomposable “MyCelia EcoWarrior'' Barbies made of mushroom mycelium and hemp, but this was an elaborate hoax. Whether they inspire nostalgia or controversy, Barbie is part of our social fabric and will likely be around for a long time. If only there was a technology that transformed her kind into harmless organic compounds! Fortunately, fungi and their microbial relatives show great promise at doing just that.
Mushrooms to the Rescue?
“Mycoremediation,” writes mycologist and author Paul Stamets in Mycelium Running, “is the use of fungi to degrade or remove toxins from the environment” and various fungi including Pleurotus, Trametes, and Aspergillus have been shown to be effective in capturing heavy metals and removing pollutants such as Polychlorinated biphenyls (PCBs) from soil. What’s more, fungi have been utilized to eliminate harmful E. coli bacteria from the Chicago River, detoxify oil spills in the Ecuadorian Amazon, and remediate contaminated soils in New Zealand and Finland. There is an Amazonian fungi that eats polyurethane, and a bacterium isolated from a Japanese recycling facility that degrades Polyethylene terephthalate or PET, a common polyester found in single-use plastic bottles. In fact, the Royal Botanic Gardens has identified over 430 species of fungi and bacteria capable of degrading plastic using a host of enzymes normally reserved for degrading decay-resistant plant cell wall components like lignin, cellulose, and hemicellulose.
Oyster mushrooms growing on contaminated waste; part of a mycoremediation project by CoRenewal
While this is all great news and serves as a step in the right direction, mycoremediation efforts can be daunting.
In order for fungi to be effective at remediation, they must receive the right conditions for growth at each site, which includes the correct soil moisture, pH, temperature, and air flow in addition to the correct substrate, or mushroom food. “Mycoremediation is currently very site-specific,” says Peter McCoy, author of Radical Mycology. Each solution is tailored to the pollution it targets, and plastics don’t magically disappear overnight, but are slowly broken down over months or years into smaller subunits, or monomers, which remain in the soil until something else comes along that can break them down. Site treatments will often “focus on one species of mushroom,” according to Dr. Lauren Czaplicki, founder of Fungal Solutions, rather than a community of “countless fungi and bacteria [that] work together to digest soil and make it habitable for other organisms.” She envisions the ideal “site microbiome” including all the necessary microbes to convert plastic to its smallest and most harmless constituent parts. All links in the chain must be present for it to work correctly.
Solutions to Plastic Waste
While 175 members of the United Nations agreed to develop an international framework to reduce plastic waste and a smaller coalition seeks to end all plastic pollution by 2040, as long as the market for them exists, corporations like Mattel will continue churning out products that contribute to climate change, choke the oceans, and take hundreds of years or more to decompose, if they do at all. Some have pointed to bioplastics as a possible solution to the problem but they are often just as toxic and not much more environmentally friendly than traditional plastics. French company Carbios seeks to utilize “enzymatic recycling” to recycle PET, the common polyester in plastic bottles, but questions about cost and scalability remain. Reduced equipment, labor and energy costs benefit mycoremediation but its scalability remains in question. Since 40% of all plastic produced is used in packaging single-use products, perhaps a more radical approach to the problem is eliminating plastic packaging entirely. New York-based Ecovative is leading the effort in this arena with its MycoComposite, a mycelium-based material developed for home insulation and packaging. This is a step in the right direction, and we are excited to see how this fledgling technology progresses alongside the growing industrial packaging market. It will only fuel the current love affair with mushrooms that, with luck, leads to a paradigm shift in appreciation for mycology, the potential of mycoremediation, and the adoption of mycelium-based products that may one day replace plastic.
Alex Hirsig of Cal Poly San Luis Obispo inspecting the first iteration of a mycomaterial constructed with almond hulls, a project undertaken in partnership with North Spore's research program
Nuclear Energy = Novel Fungi Food?
When J. Robert Oppenheimer coordinated the detonation of the first atomic bomb in July of 1945, setting the stage for the Atomic Age, he could not have known that the energy he helped shepherd into the world would some day feed hungry fungi. 40 years later in 1986, an explosion at the Chernobyl Nuclear Power Plant in present-day Ukraine released 400 times more radioactivity into the environment than the atomic bomb dropped on Hiroshima in August of 1945. Thirty-one people lost their lives in the immediate aftermath, and an estimated four thousand deaths can be attributed to radiation over the ensuing decades. While the area has mostly recovered from the incident, a 20-mile exclusion zone still exists around the damaged plant due to the continued presence of radioactive elements like strontium and caesium, which are linked to leukemia and liver damage. Within the restricted area, scientists documented the return of wildlife along with the presence of numerous fungi, including a jet-black variety of the common soil yeast Cryptococcus neoformans growing on the walls of the damaged reactor.
Mushrooms growing in the radioactive Chernobyl Exclusion Zone
It was clear that these fungi were thriving in the inhospitable environment, and it was hypothesized that their dark pigmentation had something to do with their ability to withstand the high levels of ionizing radiation, the kind of energy that can alter molecules within living cells.
Further study confirmed that the dark fungi collected at the Chernobyl site grew faster in the presence of radiation through a process called radiosynthesis, where the pigment melanin (responsible for the darkened coloration in the fungi as well as in the hair, skin, and iris of the eyes of people and animals) facilitates the absorption and transformation of nuclear radiation into usable energy within the fungus akin to the way plants use sunlight to drive photosynthesis. Indeed, these “radiotrophic” or radiation-eating fungi benefit from exposure and thrive in the harsh environment, a discovery that sits in contrast to the notion that radiation is generally harmful to living things. A study investigating the effects of a month-long spaceflight on the same fungi found that melanin-containing varieties had 50 percent higher viability than those without it, suggesting a protective effect that may come in handy in future missions. While the research team speculates these fungi may one day serve as a source of food for astronauts on long journeys, Johns Hopkins University researchers are testing the feasibility of fungal-derived melanin as an interstellar sunscreen against harmful radiation, adding to the many ways fungi could support life in space.
Final Thoughts
Fungi are some of the most multifaceted, resilient, and adaptable organisms on the planet. They create soil, sustain healthy forests, serve as a low-impact protein source and therapy for hard-to-treat disorders. Fungi present unique opportunities to adapt to climate change and reduce our dependence on fossil fuels, and their capacity to produce a cornucopia of enzymes allow them to digest materials as diverse as wood, TNT and plastic waste. While they may seem to have very little in common with the two most popular movies of 2023, a deeper dive into the humble lives of fungi yields interesting connections to both plastic waste and nuclear radiation. Could fungi hold the key to safely degrading Barbie dolls? What would J. Robert Oppenheimer, the father of the atomic bomb, say about using radiation-munching fungi as a stepping stone to living elsewhere in the cosmos? In Hollywood and beyond, it is clear that we are just beginning to open our eyes to fungi’s vast potential.