you're reading...


A boon to ocean conservation? Certain fungi can degrade marine plastics

Brunner I, Fischer M, Ru ̈thi J, Stierli B, Frey B (2018) Ability of fungi isolated from plastic debris floating in the shoreline of a lake to degrade plastics. PLoS ONE 13(8): e0202047.

About a year ago, I decided to make a move towards reducing my plastic consumption. Working in environmental conservation leaves you with a crushing grey cloud of guilt any time you fall into bad habits : forgetting your reusable bags, buying food wrapped in plastic, wearing yoga pants, buying a disposable Starbucks cup, and many other privileged wasteful behaviours.

So I made a commitment to cut certain plastic-containing products and activities out of my life, intending to do my duty to environmental sustainability and to encourage my family and others to do the same. So far, it’s going well. It’s been difficult to find a butcher and dairy that will allow us to purchase plastic-free meats and milk products, but the rest of our food now comes without packaging. I don’t let myself go to the store without bags, even if it’s inconvenient to stop at home first, and I’m slowly switching to reusable feminine products. I am having a hard time with my clothing, though.

A plastic micro fibre, ripped away from a synthetic fabric and now suspended in water (M.Danny)

The majority of our clothes are now made from synthetic plastic polymer fabrics that give them a stretchy character – the nylons, organzas, faux leathers and furs. Your shirts, your shoes, and my treasured yoga pants all contain at least some plastic threads, some upwards of 75%. It’s become so ubiquitous that it’s difficult to find fabrics that don’t contain any plastic (look for labels like “100% cotton” and ”100% linen”).

This might explain why plastic microfibers are being found so often in our oceans.

Plastic pollution comes in all shapes and sizes. From large floating whole-piece plastics like bags, pens, and bottles all the way to tiny microplastic particles, the product of either early-production losses or the byproduct of slow breakdown of larger pieces. The trouble with plastic is that, unlike other forms of pollution, it never really breaks down into its constituent forms. Instead, plastic photodegrades (breaks apart in response to light) into smaller and smaller pieces, chemically identical to the original larger piece. Every time you wash your clothes, plastic microfibers enter our waterways destined for the ocean. There, they get taken up by the marine food web and enter the sediment, adsorbing harmful chemicals and choking out ocean life.

Luckily for my yoga pant addiction, Swiss researchers recently discovered a number of fungi that seem capable of decomposing polyurethane, the kind of plastic often used in clothing and responsible for microfiber pollution.

Brunner et. al. from the Swiss Federal Institute for Forest, Snow, and Landscape Research published an article in PlosONE recently that show how certain fungi can decompose plastic. Taking samples from Lake Zurich in Switzerland, the researchers presented separated plastic debris particles in petri dishes with a growing medium rich in nutrients important for fungal growth. After a few weeks, they found hundreds of different fungal strains growing in the plates and were able to isolate and identify 13 species (12 Ascomycota and 1 Oomyctoa, in case you’re interested!)

They then tested the ability of the fungi to degrade plastics by isolating fungal inoculi (basically fungal patches) and placing them on one of three surfaces: polyurethane (the plastic in synthetic fabrics), polyethylene (the plastic in bags, toys, pens and other common products), and lignin (a plastic-like but plant-derived polymer that is also difficult to break down).

Cladosporium cladosporioides, a fungus found on the researchers’ marine plastic samples capable of degrading polyurethane (Medmyco)

Four species found on the plastic debris were able to break down the polyurethane, with Cladosporium cladosporioides being the most efficient. Surprisingly, very few of the fungi that naturally degrade lignin, which is the natural tough material plant cell walls are made of, were able to also degrade the plastic. No fungi were able to degrade the polyethylene, the polymer that at least of third of plastics are derived from. The researchers also tested 23 other fungi species not found on the plastic debris from Lake Zurich, and only found 3 more fungi capable of degrading polyurethane.

So it seems rare to find a fungus that can degrade the plastic particle it’s hitched a ride on. However, Brunner et. al.’s results make me feel a little better about not being able to kick my yoga pant habit. Polyurethane seems a little easier to decompose, meaning given the right fungal environment, those pesky microfibers might adequately break down after leaving your washing machine. But polyethylene is tough, and even polyurethane plastics seem unlikely to degrade in nature by fungal action alone. However, if researchers like the Swiss group can identify microorganisms that do degrade different polymers, it might allow plastic manufacturers to design new plastics with those natural degrading agents in mind.

For help cutting your plastic habit, check out these tips from the awesome blog “My Plastic Free Life”


No comments yet.

Post a Comment


  • by oceanbites 3 months ago
    Happy Earth Day! Take some time today to do something for the planet and appreciate the ocean, which covers 71% of the Earth’s surface.  #EarthDay   #OceanAppreciation   #Oceanbites   #CoastalVibes   #CoastalRI 
  • by oceanbites 4 months ago
    Not all outdoor science is fieldwork. Some of the best days in the lab can be setting up experiments, especially when you get to do it outdoors. It’s an exciting mix of problem solving, precision, preparation, and teamwork. Here is
  • by oceanbites 5 months ago
    Being on a research cruise is a unique experience with the open water, 12-hour working shifts, and close quarters, but there are some familiar practices too. Here Diana is filtering seawater to gather chlorophyll for analysis, the same process on
  • by oceanbites 6 months ago
    This week for  #WriterWednesday  on  #oceanbites  we are featuring Hannah Collins  @hannahh_irene  Hannah works with marine suspension feeding bivalves and microplastics, investigating whether ingesting microplastics causes changes to the gut microbial community or gut tissues. She hopes to keep working
  • by oceanbites 7 months ago
    Leveling up - did you know that crabs have a larval phase? These are both porcelain crabs, but the one on the right is the earlier stage. It’s massive spine makes it both difficult to eat and quite conspicuous in
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring Cierra Braga. Cierra works ultraviolet c (UVC) to discover how this light can be used to combat biofouling, or the growth of living things, on the hulls of ships. Here, you
  • by oceanbites 7 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Elena Gadoutsis  @haysailor  These photos feature her “favorite marine research so far: From surveying tropical coral reefs, photographing dolphins and whales, and growing my own algae to expose it to different
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  on Oceanbites we are featuring Eliza Oldach. According to Ellie, “I study coastal communities, and try to understand the policies and decisions and interactions and adaptations that communities use to navigate an ever-changing world. Most of
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Jiwoon Park with a little photographic help from Ryan Tabata at the University of Hawaii. When asked about her research, Jiwoon wrote “Just like we need vitamins and minerals to stay
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring  @riley_henning  According to Riley, ”I am interested in studying small things that make a big impact in the ocean. Right now for my master's research at the University of San Diego,
  • by oceanbites 8 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Gabby Stedman. Gabby is interested in interested in understanding how many species of small-bodied animals there are in the deep-sea and where they live so we can better protect them from
  • by oceanbites 9 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Shawn Wang! Shawn is “an oceanographer that studies ocean conditions of the past. I use everything from microfossils to complex computer models to understand how climate has changed in the past
  • by oceanbites 9 months ago
    Today we are highlighting some of our awesome new authors for  #WriterWednesday  Today we have Daniel Speer! He says, “I am driven to investigate the interface of biology, chemistry, and physics, asking questions about how organisms or biological systems respond
  • by oceanbites 10 months ago
    Here at Oceanbites we love long-term datasets. So much happens in the ocean that sometimes it can be hard to tell if a trend is a part of a natural cycle or actually an anomaly, but as we gather more
  • by oceanbites 10 months ago
    Have you ever seen a lobster molt? Because lobsters have exoskeletons, every time they grow they have to climb out of their old shell, leaving them soft and vulnerable for a few days until their new shell hardens. Young, small
  • by oceanbites 11 months ago
    A lot of zooplankton are translucent, making it much easier to hide from predators. This juvenile mantis shrimp was almost impossible to spot floating in the water, but under a dissecting scope it’s features really come into view. See the
  • by oceanbites 11 months ago
    This is a clump of Dead Man’s Fingers, scientific name Codium fragile. It’s native to the Pacific Ocean and is invasive where I found it on the east coast of the US. It’s a bit velvety, and the coolest thing
  • by oceanbites 12 months ago
    You’ve probably heard of jellyfish, but have you heard of salps? These gelatinous sea creatures band together to form long chains, but they can also fall apart and will wash up onshore like tiny gemstones that squish. Have you seen
  • by oceanbites 12 months ago
    Check out what’s happening on a cool summer research cruise! On the  #neslter  summer transect cruise, we deployed a tow sled called the In Situ Icthyoplankton Imaging System. This can take pictures of gelatinous zooplankton (like jellyfish) that would be
  • by oceanbites 1 year ago
    Did you know horseshoe crabs have more than just two eyes? In these juveniles you can see another set in the middle of the shell. Check out our website to learn about some awesome horseshoe crab research.  #oceanbites   #plankton   #horseshoecrabs 
WP2Social Auto Publish Powered By : XYZScripts.com