The blog formerly known as   Fake Plastic Fish

May 22, 2012

Plastic-Eating Fungi: Environmental Salvation or Distraction?

Recently, several readers, including my dad, have forwarded me articles about a group of Yale students who discovered an Amazonian fungus (pestalotiopsis microspora) that can not only eat polyurethane plastic, but can actually survive on it as its sole source of carbon. Could a fungus be the solution to our plastic pollution problem? And what does it mean in terms of the kinds of plastics we see littered every day?

Let’s stop and think it through.

There are many different types of plastic polymers. In general, single-use disposable products, the kind that make up the bulk of municipal plastic waste, are made from polyethylene terephthalate, high and low density polyethylene, polyvinyl chloride, polypropylene, or polystyrene. Not polyurethane. Polyurethane is used as foam for furniture cushions, car seats, and mattresses; garden hoses; footwear; liquid varnishes;  and a whole host of other durable products–not the kind that are routinely littered. So a fungus that eats polyurethane is not going to affect most of the plastic waste that ends up in the landfill or incinerator or environment.

But perhaps this organism is just one of many to be discovered that will break down other kinds of plastics. In 2008, a Canadian high school student discovered a type of bacteria that could break down polyethylene bags. Musing on the ramifications of his discovery back then, I wrote:

But does this mean that plastic bags are now off the hook and that plastic packaging has been redeemed? Can we continue to use as much of it as we want guilt-free? Plastic is still made from non-renewable fossil resources. It’s manufacture uses energy and creates pollution in the form of pre-production plastic pellets, aka nurdles, that can escape and cause harm to the marine environment. And unlike paper bags which biodegrade easily and naturally when exposed to the elements, plastic bags will need to be processed in a controlled way at a temperature of 37°C (99°F) because the microbes that break them down don’t exist in abundance in the natural world, certainly not in the cold ocean.

Using microbes to dispose of waste is otherwise known as composting. We compost food scraps and some bio-based plastics now, and perhaps some day, we will be able to compost fossil-based plastics using bacteria, fungi, and other organisms. But we need to keep in mind that composting is simply a method of waste management. It’s better than landfilling and incinerating, but it does nothing to reduce the amount of new plastic being produced in the first place. It doesn’t address the massive amounts of plastic polluting the ocean and other areas of our planet. And it certainly doesn’t mitigate the toxicity of the chemicals used to make plastics and plastic products.

While it’s useful to find “natural” methods to deal with the plastic waste that already exists, the real solution is reducing the amount of plastic we use in the first place by refusing single-use disposable plastics and lowering our consumption of other plastic products. If news of these new technologies gives consumers the impression that it’s okay to consume plastic as usual, is it possible that this information could do more harm than good?

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10 years ago

Hi Beth, Excellent as usual. Are you attending the CRRA event in SF next week?

Beth Terry
10 years ago
Reply to  clkk411

I gave a talk at the Zero Waste Youth Convergence on Sunday, but that’s all I have time to do. Will you be here?

11 years ago

I’m concerned that any organism that can digest polymers will also excrete methane, CO2 or some other form of carbon into the atmosphere. The potential volume may be trivial compared to the greenhouse gases produced by energy production, but it’s something to be considered. There’s no such thing as a free lunch… even for fungi.

11 years ago

People have become too used to the disposable plastic life style-I hope that this attitude changes before we literally drown in plastic soup!

11 years ago

And polyethylene is not that bacteria’s preferred food, so plastic is not what the bacteria will be eating 99% of the time. – Green Life Studios

11 years ago

Even the rivers and seas have the power to clean itself but not at the rate we pollute it. Now imagine the ammount of plastics we use and how many funghi will be needed to digest it! There’s a balance that should be respected.

11 years ago

We all know that there’s a cost for everything. An exchange. Those that created the plastic world we inherited may or may not have considered that. Until those who are in the business of inventing and selling products for mankind are motivated by higher reasons than profit, we are doomed (perhaps) to repeat discoveries that what we thought was safe for life isn’t. Chessplayers think many moves in advance. We need to insist that innovators do that as well.This fungus could start as a blessing and end up as a curse, as others have mentioned. In the natural world problems and solutions live side by side. I just don’t know about the plastic world.

My Plastic-free Life
11 years ago

Hi Suzie. I’m guessing fungi from the Amazon probably wouldn’t survive in the marine environment. Plus, we don’t know what their impact would be on that delicate ecosystem.

Caley Concannon
11 years ago

Great points, thanks for sharing

Theresa P
11 years ago

Check out the very interesting novel Ill Wind by Kevin J. Anderson and Doug Beason about a microbe that was designed to clean up oil spills but ends up consuming anything that’s petrocarbon-based. It was a great read for plastic-free enthusiasts.

Some dude
11 years ago

I would love to see microbes able to break down plastic. It would be a great help in cleaning up the mess of all the existing plastic. We would of course have to consider what byproducts come from this type of reaction and the energy inputs required. I definitely don’t think it’s a reason to continue making more plastic, since it fails to address so many of the other issues that you’ve pointed out like accumulation in the ocean of pre production particles and the toxicity of chemicals found in plastic items. As for the people stating we should just toss these microbes into the gyres and let them go to town; I wish it were that simple, but the breakdown process will require very specific temperature and pH conditions and it just isn’t as easy as dumping plastic eating microbes into the ocean.

So lets all keep up our efforts in reducing plastic, hope that we can devise some sort of cleanup solution for the stuff already made and really hope that it doesn’t reinforce the concept that plastic is okay!

11 years ago

Seems that if these fungi can be used to help deal with the polyrethane waste that could be a huge waste management/landfill space benefit. When was the last time you saw a mattress/car seat/furniture cushion made from something eco friendly and biodegradable? While these durable goods are meant to last years, they eventually end up in a landfill so these fungi could certainly help on that end of things.

11 years ago

In my not so humble opinion, microbe eaters are not the answer. The first step to reaching a sustainable future is just what this blog is about – starting to eliminate plastics from the household and then perhaps getting rid of them altogether. We need to think about how much we consume and the areas we can reduce our dependence on fossil fuel as soon as possible. The amount of plastic shopping bags in the world is insane, especially when such a “simple” task of grocery shopping is quite often planned, even lists are made what to buy, then usually the goods are tucked conveniently into the trunk and off to home. The packaging materials aside for a moment, is it so hard for a small family to dedicate 4, 5 or 6 grocery bags made from a natural and compostable material such as hemp or organic cotton or strong nettle fibers?

And what about plastic clothing? Sure it is cheap and it clothes the world, however if we were demanding creatures, maybe we could learn to do more with less and add a touch of quality and timelessness wherever we are, whatever we are doing…

Are we trying to manipulate Nature for our good our hers?

Dawn Lee
11 years ago

I saw a documentary, scientists say plastic breaks down over time and emit toxic fumes and particles that are released unbeknownst. The older the plastic the more toxic it is. Check your old plastic at home especially in your kitchen and food product containment.

Suzie Haynes Halle
11 years ago

nice blog. We do need to reduce our use of plastic. Amost impossible to make a meal and not toss some plastic into the trash these days… But why not release these plastic fungi’s into the 5 gyres and let them have a go at dissolving it?

Nancy Nathan Baldwin
11 years ago

Excellent post Beth and I agree with one of the other comments. Your writing ability keeps me speechless. I write like I talk….not sure if that’s good or bad but its what I do. lol

11 years ago

Using microbes to dispose of waste is otherwise known as composting. = Brilliant!

When I trouble to ask makers and distributors of so called “compostable” plastics what exactly the plastics break down into, I never get a satisfactory or believable answer. Blicut let’s say these petroleum products can be broken down into non polluting substances. Are municipalities and therefore the public responsible for inventing digestion plants and for implementing collection, separation and “compost” distribution?

Make companies take back their own waste and they’ll figure something out if they have to pay for it.

Carmen Melton
11 years ago

That’s exactly how I feel about recycling. In Denver there are no facilities that accept polystyrene. So on the few occasions I’ve unwillingly ended up with it, I am at a loss. If the city decided to start taking it along with all other recyclables, people (who recycle) might not refuse it, and then more and more would be produced “guilt-free” as it is sooo cheap. As it stands now, what little I have will end up in a landfill. So not having recycling options gives me a stronger commitment to avoiding it even more fiercely in the future. But that’s me. What about the conscious of the average American on “guilt free” solutions? So I see your point, and the only answer I can come up with is a higher collective awareness of the problem. Not so simple:)

11 years ago

“It doesn’t address the massive amounts of plastic polluting the ocean and other areas of our planet” Um….yes it does…directly….by letting these microbes loose on it? I agree with your other points though.

11 years ago

Excellent analysis. I wish I had inherited your writing ability and motivation to put pen to paper!

The Flotsam Diaries
11 years ago

Surprises me that no scientist (that I know of) has replicated that high-schooler’s feat, now 4 years later. I’m equally skeptical that the exotic Amazonian fungus truly digests polyurethane. Until those tests are repeated, they’re “maybe”s.

And can you imagine what would happen if microbes that -could- eat a wide variety of plastics started multiplying in the environment? Even assuming that the global introduction of a new form of life didn’t totally whack out ecosystems, there are a lot of things made out of plastic that wouldn’t take well to being eaten. House decking, park benches, car bumpers & tires, boat hulls, now even bridge trusses and other structural elements.

We were stupid to build the modern world on material whose selling point was that nothing ate it or degraded it. But that’s what we’ve done. And if it’s going to change, I sure hope we’re the ones driving the change, and not just passengers on some wild microbial ride.