As programmers we are always attuned to thinking about the edge cases and endgames, so I wonder:
Would be possible that such a fungus proliferated into a sort of "termite for plastic", feeding on plastic piping (in houses or cars maybe) and the like.
Of course house owners already deal with mold so I suppose this would just be another one.
The article suggests introducing it into landfills to eat the plastic. Kudzu was introduced to America to control soil erosion. The invasive vine now spreads at a rate of 150,000 acres a year, so it certainly accomplished goal A.
The ability of bacteria to consume and destroy infrastructure is bounded by energy and resource considerations. Observe that we use wood for structures all the time, a material that can be consumed by any number of very common bacteria that we don't need to hypothesize about, yet properly cared-for wood can last hundreds of years.
True, but we didn't care for plastic the same way, because we didn't need to. Until now. It's not the end of the world, of course, but we should prepare for this problem.
In europe we have a similar problem with japanese knotweed. In the UK it's classed as "controlled waste" and has to be disposed of using chemicals. It's illegal to wilfully spread it.
The article is scant on details, but it does say that researchers want to use the enzyme extracted from the fungus to break down plastics, not introduce the fungus itself to our piles of garbage. This makes it a bit different from the case of the Kudzu vine.
The article says that the fungus digests polyurethane - maybe if the fungus is focused on one type of plastic that will only be used for disposable products, the problem can be avoided?
One interesting thing that this article fails to mention is that the fungus was discovered by an undergraduate student. Jon Russell, the lead author of the paper, graduated last spring, and he originally discovered the fungus in Spring 2008. Yale offers a class that pays for students to spend Spring Break in the Ecuadorian rainforest collecting samples. The class also includes a stipend for students to continue their research projects during the summer following the course.
One of my greatest regrets from undergrad days was having graduated a year too early to enroll in this course. Scott Strobel was something of a visionary for setting it up, and it seems to have paid off with at least one cool result -- not to mention, a handful of students who now know how it feels to find something new.
I wish more professors would actively engage their students in "real" research projects, i.e. beyond the usual cookie-cutter laboratory lessons or follow-a-grad-student internships. Sure, it's more work for everyone involved, but experiences like this are the best way to convert bright students into real scientists, IMO.
This reminds me of the book Ringworld and the "Fall of Cities" - the civilization had become dependent on a particular superconductor, and wired it into everything. A microorganism that fed off of the superconductor came along and spread like wildfire. The side-effect was that it essentially wiped out the civilization because their entire energy infrastructure was built around this stuff.
I was thinking the same thing. Getting a colony of this stuff established in the voids and nether regions of say a wide body jet would not be a very good thing at all.
I imagine that jets are inspected often enough for something like this to be caught. I imagine that a bigger problem would be an infection getting loose in a manufacturing factory. How much of my laptop is edible?
I'm confused by the "exclusively subsists on polyurethane" and "scientists recently found a fungus in the Amazonian rainforest"... TIL there's a bunch of polyurethane in the Amazonian rainforest?
That caught my eye, too. Rather than having evolved to eat polyurethane only, and then waiting patiently for us to arrive with dinner, I took this to be an awkward way of reiterating that the fungus is the only organism we know of that can eat PU. Which does make me wonder a bit about what it normally eats - resins?
Polyurethane, like virtually all plastics is made of nitrogen, carbon, hydrogen and oxygen. So the byproducts are things like water, carbon dioxide, ammonia, alcohol.
Plastics burn really well, they are not actually that hard to destroy safely - their decomposition products are very clean if the fire is hot enough.
It's possible to burn polyurethane safely, but it's not trivial. If you burn it at low temperatures, you get hydrogen cyanide, and if you burn it (or, in air, anything) at high temperatures, you get deadly nitrogen dioxide instead. You can get rid of the nitrogen dioxide with sufficient effort; http://www.aat.cc/store.asp?pid=26808, for example, sells a six-stage air scrubber system using a sequence of strong oxidizing and reducing agents.
In short, "not actually that hard to destroy safely" is wildly off the mark.
Your other statement is wildly off the mark, too. Metabolic byproducts are incredibly diverse, including all of the chemical compounds produced in the course of an organism's life cycle. One of the organisms studied in this paper was Aspergillus niger, whose metabolism produces, among other things, aflatoxin. EDIT: Oops, WRONG. It's other Aspergillus species that produce aflatoxin, sorry. A. niger is mostly notable for producing 99% of the citric acid in your food.
I should also point out that there are plastics that are even harder than polyurethane to burn safely, namely, anything containing chlorine or fluorine. The common ones are polytetrafluoroethylene (Teflon) and poly(vinyl chloride) ("vinyl"). These, regardless of how you burn them, are going to produce compounds of fluorine and chlorine, typically gaseous hydrofluoric and hydrochloric acids, which will EAT YOUR FUCKING LUNGS. HF will also poison the fuck out of you. On the plus side, these gases are light and will disperse rapidly if they're not confined.
Nitrogen dioxide is a problem, but at an industrial scale it's not a huge problem. Among other things it can easily be captured with fractional distillation (water, CO2 and NO2 have very different boiling points), converted to nitric acid and sold.
And aflatoxin (and others) are not byproducts, they are deliberately made by the organism, regardless of what it eats. A byproduct is waste that depends on the food source.
This seems like the most important question... Since the paper is paywalled, and science reporting is terrible, can someone with access inform us just what the hell the fungus turns the plastic into?
There are two competing methods, as far as I see: use the bacteria themselves to digest plastic, or use extract the enzyme responsible for plastic dissolution and manufacture it the enzyme responsible for plastic dissolution.
1. Bacteria:
- Can they adapt to the climate and the ecology of their target environment?
- Can they adapt, in particular, to oceanic salt water to dissolve dumped plastic waste?
- Overpopulation: what are the consequences? Do natural predators of this bacteria exist?
- Underpopulation: can the bacteria be genetically modified to survive in landfills or oceans? Must they be isolated in a controlled environment with plastic?
2. Manufacturing
- If the enzyme/manufacturing process is controlled by a profit-seeking corporation, would this mean unequal pollution capabilities between the developed and developing worlds? I suspect more plastic waste is improperly disposed by developing countries - thus further exacerbating the problem.
- Must the bacteria manufacture the enzyme necessary, or can an enzyme be chemically manufactured?
- Does the enzyme have an optimal/useful operating temperature? The Amazon rainforest is not only a freshwater environment, but also a relatively warm climate. Our waste may be captured by cold ocean currents or be present in countries simply far too distant from the equator for this to be a feasible option.
3. Process consequences
-What are the products of plastic dissolution by this bacteria?
-If the process is performed inefficiently/incompletely due to some environmental factors (water salinity, pH, temperature), are there any harmful byproducts?
-If the process produces simple chemicals - do these harm other organisms in the environment surrounding the bacteria?
-Would the accumulation of the products (CO2 gas for example) further global warming or pollution?
Yeah. A lot of plastics are 100 percent recyclable. Eventually you just mine the landfill if it is worthwhile. No? Destroying the plastic seems a waste.
Possible selection and confirmation bias as I design plastic products.
A ton of them are recyclable in their pure state, but I get the impression that a lot of seemingly mundane plastic products these days are actually surprisingly complicated mixes/composite materials: I know something simple like a potato chip bag is at least a 3-layer composite structure, and you've got inks from the label, metal from the barrier layer, polypropylene from the film, and polyethylene from the adhesive layer.
On top of that, the polypropylene film itself is likely a multilayer structure of different copolymers and crystallinities, and it all turns a crappy little thing like a chip bag in to something damn hard to recycle.
Yeah, we already mine tailings from old mines, since the old mining processes were less efficient, and those tailings are now considered economically recoverable ores.
Reading the paper (paywalled, unfortunately), it seems that the big breakthrough was not that a microbe can degrade polyurethane (there's almost a dozen other citations), but that this one can do it both aerobically and anaerobically. That means that you can introduce it to a dump, and it will work in both the deep and surface layers.
The discovery here is an endophytic (living in a plant) fungus that can grow anaerobically, using polyurethane as its sole carbon source.
The authors suggest fungi that digest polyurethane have been known for decades. ("""Enzymatic degradation of PUR has been demonstrated by both fungi (4, 5, 6, 19) and bacteria (14, 17, 23).""")
They cite one reference from 1968, which itself implies polyurethane-degrading fungi had been known long before then:
It would be great to have something eating all the plastic in the oceans other than the fish. And we really REALLY need to start doing something about the trash gyres in the seas.
I'm definitely for cleaning up the gyres, but how do we know that this is something that can be controlled? It's not just plastic that's floating around, either. I'll note that this is a tremendous discovery and I hope we can see it through..
I had hoped to craft a joke about a scientist's iPad disintegrating halfway through his presentation, but that topic has been covered. So instead I'll object to "Yale discovers ...". Really? Yale did it? Imagine a world in which that's the rule -- imagine a headline in 1905 saying "Swiss patent office discovers new theory about the universe."
Seems reasonable enough to me. It would be different if the ex student had completed their studies at Yale and went on to research something different independent of Yale. Here though it sounds like they were funding it and that it was a continuation of research being done while a student.
How would they have identified this fungus for it's properties in the Amazon rainforest? Do they just leave a piece of plastic near a tree and come back to see if anything's growing on it?
Scanning through the abstract[1], it seems pretty likely to me that they did the actual screening in a lab, and it's merely that the fungus was originally from the rainforest. In fact, one of the 21 authors on the paper is from a Peruvian university, and he's likely the one who's group originally isolated the fungus.
This reminds me of a YouTube video, I saw within the last ten days here, where a stand-up comedian talks about, how the planet does not need saving, it will find out ways to save itself. I can't find it now though.
Scientists cannot find a way to degrade plastic does not necessarily mean plastic is not bio-degradable.
I have found time and time again, that stand-up comedians are the ones who make the most serious points.
This topic was rather fully explored in a 1971 book:
Mutant 59: The plastic eaters by http://en.wikipedia.org/wiki/Kit_Pedler and Gerry Davis (both affiliated with Dr. Who)
As a kid that book seemed captivating(scenes of disintegrating airplane, sewage exploding etc.), upon rereading it some years later the plotting and characters seem hackneyed.
When all those carbon-based life forms died all those years ago, there was nothing to break them down. So they persisted, and the result is oil and coal.
I've often wondered whether a similar thing would happen to all this plastic lying around. I suppose it's still sort of a toss-up, but now I'm at least sort of convinced that it's vaguely possible.
> When all those carbon-based life forms died all those years ago, there was nothing to break them down.
There was nothing to break them down not because such a thing did not exist but because they were protected from those organisms: they were buried under anoxic conditions (complete lack of oxygen) or beneath acidic waters, shielding the organic matter from that which would normally degrade it by feeding on it.
Whoever voted negative on this comment does not fully understand my point. I am pointing out how ridiculous it is to believe that all life started 6,000 years ago and all species were already made exactly as they are. The fact that this particular fungus is surviving by eating plastic simply states that evolution happened and is still happening. Or maybe he did fully understand but just got offended by my mockery of the Judeo-Christian-Islamic version of how the universe, the world, and life began.
Or maybe they understood you and thought that your hate mongering vitriol doesn't belong here. No one brought up evolution or creationism here but you.
Hate? is telling the truth hate? Religion is an idea. Like any other idea it should be subjected to scrutiny and criticism. Unfortunately in our culture criticizing religion is considered wrong. I did not even criticize any religion in particular but criticized a specific idea, an idea contradicted by scientific evidence. Religion should not be untouchable when its teaching contradict science. No Hate mongering or vitriol here. Implying that the doctrine of special creation is flat wrong is not hate mongering, it is simply telling the truth.
It is not off subject. This is very strong evidence for speciation. The discovery of such fungus has wide implications, from industrial applications to proving the theory that life adapts and continue to evolve. It is related because the very existence of this life form proves a scientific theory.
I apologize if the way I said it was offensive. But I will not apologize for telling the truth. The idea that we evolved is not just an opinion, it is a fact backed by evidence. I couldn't say the same about the doctrine of special creation.
Now that's great news! I would be interested in the environmental impact of this fungus though. It would not be a good thing if the fungus turns out to cause more damage than the plastic itself.
One of the most important things we learned from early 20th century conservationist movement was that to "preserve" something the best thing you can do is leave it alone. Every time they tried to correct something in a ecosystem something else would break. They messed up a lot of Stuff in yellowstone until they learned to just let it be.
this fungus could end up contributing to global warming, by taking the carbon that is trapped as plastic on the ground and releasing it eventually into the atmosphere.
the last paragraph is the most depressing part, just as weve found a sustainable ecological solution to problem of plastic, we learn that someone has commoditized it into a chemical solution, which no doubt has the accompanying legal patent absurdities,few if any positive environmental interactions and actually endangers a very special species due to corporate anti competative behaviour.
Irony anyone?
the environment is a holistic function of living symbiotic relationships. Isolating an enzyme and spraying it on a field is about as environmentally friendly as covering a field in pus and saying its ok because it comes from nature.
yes because shit happens to be something that would occur naturally in that environment, whereas isolating some of the things that are in shit and spraying it on a field (chemical fertilizers) actually do harm in the long run.
Would be possible that such a fungus proliferated into a sort of "termite for plastic", feeding on plastic piping (in houses or cars maybe) and the like.
Of course house owners already deal with mold so I suppose this would just be another one.
The article suggests introducing it into landfills to eat the plastic. Kudzu was introduced to America to control soil erosion. The invasive vine now spreads at a rate of 150,000 acres a year, so it certainly accomplished goal A.