Between the ever-growing Great Pacific Garbage Patch, the news that over 90% of plastic isn't recycled, and the likely state of your personal trash can, it's clear that the world has a plastic problem.
Scientists around the world have continued to discover different types of fungus that can degrade specific types of plastic.
We now have 150 million tons of plastic in our oceans, according to estimates; by 2050, there could be more plastic than fish. And every new batch of trash compounds the issue: Plastic is notorious for its longevity and resistance to natural degradation.
Enter the humble mushroom. In 2011, Yale students made headlines with the discovery of a fungus in Ecuador, Pestalotiopsis microspora, that has the ability to digest and break down polyurethane plastic, even in an air-free (anaerobic) environment—which might even make it effective at the bottom of landfills. Although the professor who led the research trip cautioned for moderate expectations, there's an undeniable appeal to the idea of a speedier, cleaner, side effect-free, and natural method of disposing of plastic.
A few years later, this particular application for fungus got a jolt of publicity from designer Katharina Unger, of LIVIN Studio, when she collaborated with the microbiology faculty at Utrecht University to create a project called the Fungi Mutarium. They used the mycelium—which is the threadlike, vegetative part of a mushroom—of two very common types of edible mushrooms, Pleurotus ostreatus (Oyster mushrooms) and Schizophyllum commune (Split gill mushrooms). Over the course of a few months, the fungi fully degraded small pieces of plastic while growing around pods of edible agar. The result? In place of plastic, a small mycelium snack.
Other researchers have continued to tackle the subject. In 2017, scientist Sehroon Khan and his research team at the World Agroforestry Centre in Kunming, China discovered another biodegrading fungus in a landfill in Islamabad, Pakistan: Aspergillus tubingensis, which turns out to be capable of colonizing polyester polyurethane (PU) and breaking it down it into smaller pieces within the span of two months. (PU often shows up in the form of packing foam—the kind of thing you might find cushioning a microwave or a new TV.)
Utrecht University has continued its research, and scientists around the world have continued to discover different types of fungus that can degrade different, specific types of plastic. Khan and his team alone have discovered around 50 more species since 2017. They are currently working on finding the optimal conditions of temperature and environment for each strain of fungus to do its work.
Their biggest problem is perhaps the most common obstacle in innovative scientific research: Cash. "We are developing these things for large-scale," Khan says. "But [it] needs a lot of funding to get to the real application of plastic waste." They plan to apply for a patent soon and to publish three new articles about their most recent research, which might help boost interest and secure more grants.
Is there a way to get the fungi to work faster and to process bigger batches?
Khan's team is working on the breakdown process at this point, but researchers who want to continue in Unger's model of an edible end product also need to figure out how to efficiently and properly prepare the plastic input. "The fungi is sensitive to infection from bacteria," Unger says—which could turn it into a destructive mold. "This is a challenge for industrialization—[the] sterilization of the materials, and making the fungi resistant, strong, and faster-growing, to allow for a commercial process."
Whether it's Khan's polyurethane-chomping fungus or the edible agar pods from the Fungi Mutarium, the biggest question is still about scale. Both projects took several months to fully degrade a small amount of plastic. That's much shorter than plastic's normal lifespan, but still won't be enough to keep up with the global production of plastic. Is there a way to get the fungi to work faster and to process bigger batches?
We'd also need to figure out where these plastic recyclers would live. Could individuals keep a small compost-like heap, feeding in their own plastic and harvesting the mushrooms? Or could this be a replacement for local recycling centers?
There are still only these few small experiments for reference. But taken together, they suggest a fascinating future for waste disposal: An army of mycelium chewing quietly and methodically through our plastic bags and foam coffee cups—and potentially even creating a new food source along the way. We could have our trash and eat it, too.
At age 52, Glen Rouse suffered from arm weakness and a lot of muscle twitches. “I first thought something was wrong when I could not throw a 50-pound bag of dog food over the tailgate of my truck—something I use to do effortlessly,” said the 54-year-old resident of Anderson, California, about three hours north of San Francisco.
In August, Rouse retired as a forester for a private timber company, a job he had held for 31 years. The impetus: amyotrophic lateral sclerosis, or ALS, a progressive neuromuscular disease that is commonly known as Lou Gehrig’s disease, named after the New York Yankees’ first baseman who succumbed to it less than a month shy of his 38th birthday in 1941. ALS eventually robs an individual of the ability to talk, walk, chew, swallow and breathe.
Rouse is now dependent on ventilation through a nasal mask and uses a powerchair to get around. “I can no longer walk or use my arms very well,” he said. “I can still move my wrists and fingers. I can also transfer from my chair to the toilet if I have two of my friends help me.”
It’s “shocking” that modern medicine has very little to offer to people with this devastating condition, Rouse said. But there is hope on the horizon. Yesterday, the U.S. Food and Drug Administration approved Relyvrio, a drug made up of two parts, sodium phenylbutyrate and taurursodiol, to treat patients with ALS.
“This approval provides another important treatment option for ALS, a life-threatening disease that currently has no cure,” said Billy Dunn, director of the Office of Neuroscience in the FDA’s Center for Drug Evaluation and Research, in a statement. “The FDA remains committed to facilitating the development of additional ALS treatments.”
Until this point, the FDA had approved only two other medications—Riluzole (rilutek) in 1995 and Radicava (edaravone) in 2017—to extend life in patients with ALS, which typically kills within two to five years after diagnosis. That’s why earlier this week, Rouse was optimistic about the FDA’s likely approval of a controversial new drug for ALS.
When Relyvrio is taken in addition to Riluzole, it appears to slow functional decline by an additional 25 percent and extend life by another 6 to 10 months, said Richard Bedlak, director of the Duke ALS Clinic. “It is not a cure, but it is definitely a step forward.”
“The whole ALS community is extremely excited about it,” he said the day before Relyvrio’s expected approval. “We are very hopeful. We’re on pins and needles.”
A study of 137 ALS patients did not result in “substantial evidence” that Relyvrio was effective, the agency’s Peripheral and Central Nervous System Drugs Advisory Committee concluded in March. However, after some persuasion from FDA officials, patients and their families, the committee met again and decided to recommend approving the drug.
In January 2019, following an ALS diagnosis at age 58 in October the previous year, Jeff Sarnacki, of Chester, Maryland, was accepted into a trial for Relyvrio. “Because of the trial, we did experience hope and a greater sense of help than had we not had that opportunity,” said Juliet Taylor, his wife and caregiver. They both believed the drug “worked for him in giving him more time.”
In June 2019, Sarnacki chose an open-label extension, offered to patients by drug researchers after a study ends, and took the active drug until he died peacefully at home under hospice care in May 2020, five days after his 60th birthday. A retired agent with the federal Bureau of Alcohol, Tobacco, Firearms and Explosives who later worked as a security consultant, Sarnacki lived about 19 months after diagnosis, which is shorter than the typical prognosis.
His symptoms began with leg cramps in fall 2017 and foot drop in early 2018. A feeding tube was placed in 2019, as it became necessary early in his illness, Taylor said. He also took Radicava and Riluzole, the two previously approved drugs, for his ALS. “We were both incredulous that, so many years after Lou Gehrig’s own diagnosis, there were so few treatments available,” she said.
The dearth of successful treatments for ALS is “certainly not for lack of trying,” said Karen Raley Steffens, a registered nurse and ALS support services coordinator at the Les Turner ALS Foundation in Skokie, Ill. “There are thousands of researchers and scientists all over the world working tirelessly to try to develop treatments for ALS.”
Unfortunately, she added, research takes time and exorbitant amounts of funding, while bureaucratic challenges persist. The rare disease also manifests and progresses in many different ways, so many treatments are needed.
As of 2017, the Centers for Disease Control and Prevention estimated that more than 31,000 people in the U.S. live with ALS, and an average of 5,000 people are newly diagnosed every year. It is slightly more common in men than women. Most people are diagnosed between the ages of 55 and 75.
Most cases of ALS are sporadic, meaning that doctors don’t know the cause. There is about a one-year interval between symptom onset and an ALS diagnosis for most patients, so many motor neurons are lost by the time individuals can enroll in a clinical trial, said Richard Bedlack, professor of neurology and director of the Duke ALS Clinic in Durham, North Carolina.
Bedlack found the new drug, Relyvrio, to be “very promising,” which is why he testified to the FDA in favor of approval. (He’s a consultant and disease state speaker for multiple companies including Amylyx, manufacturer of Relyvrio.)
The “drug has different mechanisms of action than the currently approved treatments,” Bedlack said. He added that, when Relyvrio is taken in addition to Riluzole, it appears to slow functional decline by an additional 25 percent and extend life by another 6 to 10 months. “It is not a cure, but it is definitely a step forward.”
T. Scott Diesing, a neurohospitalist and director of general neurology at the University of Nebraska Medical Center in Omaha, said he hopes the drug is “as good as people anticipated it should be, because there are not too many options for these patients.”
"FDA went out on a limb in approving Relyvrio based on limited results from a small trial while a larger study remains in progress," said Florian P. Thomas, co-director of the ALS Center at Hackensack University Medical Center and the Meridian School of Medicine. "While it is definitely promising, clearly, the last word on this drug has not been spoken."
So far, Rouse's voice is holding up, but he knows the day will come when ALS will steal that and much more from him.
ALS is 100 percent fatal, with some patients dying as soon as a year after diagnosis. A few have lasted as long as 15 years, but those are the exceptions, Diesing said.
“If this drug can provide even months of additional life, or would maintain quality of life, that’s a big deal,” he noted, adding that “the patients are saying, ‘I know it’s not proven conclusively, but what do we have to lose?’ So, they would like to try it while additional studies are ongoing.” The drug has already been conditionally approved in Canada.
As his disease progresses, Rouse hopes to get a speech-to-text voice-generating computer that he can control with his eyes. So far, his voice is holding up, but he knows the day will come when ALS will steal that and much more from him. He works at I AM ALS, a patient-led community, and six of his friends have already died of the disease.
“Every time I lose a friend to ALS, I grieve and am sad but I resolve myself to keep working harder for them, myself and others,” Rouse said. “People living with ALS find great purpose in life advocating and trying to make a difference.”
The Friday Five covers important stories in health and science research that you may have missed - usually over the previous week, but today's episode is a lookback on important studies over the month of September.
Most recently, on September 27, pharmaceuticals Biogen and Eisai announced that a clinical trial showed their drug, lecanemab, can slow the rate of Alzheimer's disease. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend and the new month.
This Friday Five episode covers the following studies published and announced over the past month:
- A new drug is shown to slow the rate of Alzheimer's disease
- The need for speed if you want to reduce your risk of dementia
- How to refreeze the north and south poles
- Ancient wisdom about Neti pots could pay off for Covid
- Two women, one man and a baby