Plastic-eating enzyme could eliminate billions of tons of landfill waste
news.utexas.edu
news.utexas.edu
I would think that the most obvious solution is to not use a material that lasts thousands of years for disposable packaging that’s only needed for a few months. Seems like these types of “revolutionary” new processes to make recycling finally work come out every year, and yet nothing changes. I can’t imagine this will be any different. As long as it’s cheaper to create new plastics than it is to recycle them, nothing will change.
Also, ironically, if you start regulating it (bannings plastics straws, disposable packaging, etc...) you'll get trashed on twitter _by_ the most ardent environmentalist, (and mocked by comedians) because it is "obviously not on the scale of the problem and just green washing that is not going to help anything vote for us instead."
(source : this is what the EU is doing, and everyone is making fun of them.)
Whereas if you develop a techno enzyme to eat the plastic and sell it expensively, you'll get your bonus.
_shrug_
Is everyone making fun of us, or is it just the americans? The ban on free plastic bags in stores had widespread support and worked out quite well. The only not strictly positive thing I've heard about the proposed plastic tax is that we need to use that money to actually do something like fund cleaning of the environment or developing sustainable materials, which is a fair and obvious point and as far as I know, that is the plan.
Example : https://www.lemonde.fr/politique/article/2019/12/14/la-major...
(They have the luxury of note exactly being in power, so not having to implement any of the groundbreading and radical changes they advocate.)
I think most people would agree this is a weak policy and clearly done because its low-effort, agreeable and doesn't harm their corporate overlords much. So I can't say calling out the politicians isn't in order, but the policy itself is not actually bad. At least in my tiny corner of Europe, most of us in The Left (caps important) get this difference, but we do still have many idealists that don't, and they are usually the ones that get in the news. Maybe (I hope) it's the same over there.
// I don't have any translation software handy at the moment, so I couldn't read the article, sorry
Similar to banning plastic bags, we could replace all our disposable water bottles with higher quality *non* disposable plastic bottles. It would be slightly more expensive for companies to produce, but drastically cheaper than paying the proposed tax. Consumers may or may not treat them as disposable anyway, and there's huge health concerns over reusing plastic bottles, especially after exposure to heat.
A simple manufacturing tax wouldn't work though since we'd just start importing bottles from neighboring countries instead
If your only competitive advantage is being cheaper than the rest and now everyone is raising prices, doing the same will not only hurt your appearance as the "reliable value brand", but you'll be wasting a huge opportunity to grab a big new chunk of the market (customers tend to looks for alternatives when prices increase). These are the companies that will use alternative materials, even if they are inferior (e.g. paper straws and cups), because it's the cheaper option.
(plastic bags are, however, a pretty unique case, as they used to be free and the dynamics of "free vs paid" are way different than "paid vs paid but slightly more expensive)
Ironically, putting most plastic waste in the landfill bucket is probably more environmentally sound than “recycling” it.
"have nothing to do with recycling" is too strong a statement; knowing what type of plastic it is helps with sorting. But you're right that having the triangle doesn't automatically mean it can or will be recycled.
Not even going to get into plastics being contaminated by toxic things, leaching chemicals, microplastics, affecting acquatic life, a variety of other problems relating to plastics and excessive plastic waste.
I really wish people would push to decrease the production and use of plastics in the first place, seems more sustainable than trying to engineer solutions at the tail end of the issue. Seems to me much more effective to curtail the source of the problem than to attempt to implement solutions later on although I do appreciate that some people see the issue and are working to do something about it.
Of course we should be reducing plastic waste, and at least where I live, I've seen a big push for the reduction of of single use plastics, both through legislation, savvy consumers and responsible supermarkets.
While the biologists work on plastic-eating enzymes, product engineers can work on sustainable packaging, logistics specialists can work on low carbon distribution and politicians can work on ensuring economic motives align with a positive future for our planet.
There is hope.
Now the funny thing is that you get to see other families' trash bags once a week on their front door and there are big differences. My family has a tiny yellow bag every week and a blue one every other week whereas many others (with comparable family sizes) have 2 yellows at least and 1 blue every single week.
My guess is that they eat a lot of food coming from the supermarket: lots of wrapping, lots of cans, etc. It's an informed guess because the blue bags are transparent :-)
Have we? Or have we just seen campaigns and legislation against plastic straws and supermarket bags, which amounts to mere virtue signalling and greenwashing by corporations and governments?
We need to do much better than ban plastic straws and advertise how we've saved the world. Properly pricing in externalities onto the price of single use plastics would probably go a long way to motivate the market to give a shit.
Absolutely this.
Watching the video in the article above was a bit worrying when it gets to the end. It’s really not clear to me if the researchers have created a plastic removing enzyme or inadvertently created a tool to increase micro-plastic pollution a trillion fold.
Hoping someone can come along to tell me how stupid what I just said above is, because it’s really not my field and I’ve no idea.
Recycling is hard but we need to tackle it. Enzymes seem like a good direction - dissolve plastics to chemicals that can be re-processed and re-purposed.
And, as you say, they're pretty good carbon deposits, which is supposed to be The Most Important Thing.
... yet?
All material that can end up in landfills is already on Earth.
Is it that it comes out as methane from landfills but less harmful CO2 from a little pile? That should be solved by flaring the methane.
We need to reduce the amount of trash we produce, not hope for a miracle technology.
https://sf.curbed.com/2019/3/19/18273029/milpitas-odor-studi...
https://www.clf.org/blog/all-landfills-leak-and-our-health-a...
Plastic in a landfill is just... Stuck there. It's unnatural, sure, but it's not immensely harmful, not nearly on the same scale as CO2, and realistically, in the future, we'll be able to mine it out of there and refine it into something usable if we need it.
[0] https://www.greenpeace.org/aotearoa/publication/ghost-gear-t...
If the CO2 levels spike, life on the planet (including many or maybe even most humans) will survive. If you look at historic levels, they were hundreds of times higher and the planet was the greenest it has ever been.
If/when that toxic waste leaks out and starts killing, NOTHING will survive.
And the thing is that these are actually harming the people who are near the area where they are disposed, so the harm is more direct. CO2 is more like a global problem, so not as worrisome for the local population.
Only if you're talking about Putin's Little Green Men, in which case most were last seen heading to their deathbed in Belarus after having exposed themselves to deadly levels radiation after occupying the area and trenching it, to the total dismay of local Ukrainians and Plant workers!
Life does indeed find a way, but not in the way most think.
> In a way radioactivity is one of the easiest contaminants to deal...
What an absurd statement, if that were the case you'd go live and work in Fukushima and take advantage of all the open area and low cost real estate, and all the plentiful food that comes from that region.
Radiation to this day still hasn't been cleaned up in Chernobyl, which happened almost 40 years ago, and an Evacuation Zone is still in place.
And by the way their is an ongoing fire in the area as we speak that is cause for concern [0].
0: https://www.republicworld.com/world-news/russia-ukraine-cris...
We leak it all over the place, with no plans to plug the holes. Instead we keep adding new piping all over.
You have my sympathies for going through a this procedure even though I never had to do that.
But I'm sorry you've put such an important emphasis on having kids in your relationship. The fact that you live in a society where that's reasonable is immensely sad, to me.
You should feel whole without children, and the fact that you don't is the real tragedy, IMO.
Are you always this antagonistic and reductive?
Every couple of years this concern bubbles up. It seems to be established that sperm counts in males are going down. But I’ve yet to see substantial evidence about the possible causes. The effect of plasticisers e.g. were found in animal models usually with rather high doses. An increase of obesity over the last 50 years might also be a likely cause as obesity is linked with hormonal issues. Furthermore, the average age of first time parents has increased significantly. That could also explain why IVF got more popular as sperm counts (and egg „quality“) are age dependent as well.
AFAIK there is no empirical study today proving any link between environmental issues and sperm counts.
Apparently it's happening in dogs too: https://www.sciencedaily.com/releases/2016/08/160809095138.h...
But not necessarily in farm animals.
We know for a fact that phthalates have an effect on embryo development, and good luck avoiding those.
So while yes, for people it may be less of an issue, the same cannot be said for wildlife, where it becomes another nail in the extinction coffin.
> Per the most recent Inventory Report, U.S. landfills released an estimated 109.3 million metric tons of carbon dioxide equivalent (MMTCO2e) of methane into the atmosphere in 2020; this represents 16.8 percent of the total U.S. anthropogenic methane emissions across all sectors.
https://www.epa.gov/lmop/frequent-questions-about-landfill-g....
https://www.epa.gov/sustainable-management-food/sustainable-...
A very large fraction of those are from plastic waste in Asian countries that gets dumped into waterways instead of being landfilled.
But if you do, the smell, view, and fact that ground water becomes undrinkable will convern you. Not to mention the space they take, where little life can live on.
In the USA, you have a huge space, including deserts, so a landfill may be out of most human reach. But in France, landfills can't be far, and take the place of either a forest, or accomodations.
We don't have a better way to deal with the huge amount of trash than landfills for now. But reducing the number or size of them would be a nice to have.
I don't mean it should be a priority compared to most urging issues like climate change, but let's not get too comfy with it either.
Not even going to get into plastics being contaminated by toxic things and leeching chemicals. Landfills are not harmless to ecosystems and aquifers, either- they're a short term way of not dealing with the issue of waste materials, at best.
> ...and a circular carbon economy for PET is theoretically attainable through rapid enzymatic depolymerization followed by repolymerization or conversion/valorization into other products
> Finally, we demonstrate a closed-loop PET recycling process by using FAST-PETase and resynthesizing PET from the recovered monomers. Collectively, our results demonstrate a viable route for enzymatic plastic recycling at the industrial scale.
Thus, successful recycling of plastic would mean less new plastic being made, and less emission. Before renewables, petroleum not made into plastic would instead be burned as fuel. But now, or soon, maybe it will be left in the ground, instead, as not worth pumping out. It is better to leave carbon sequestered where it is than to extract and then sequester it.
Not saying it's good, but burning plastic if it has environmental and health benefits is not out of question. Probably most of it is burned already (it definitely is in Asian countries).
Germany seems to have invented the term "thermal recycling", i.e. burning plastics. IIRC, it is actually considered a renewable energy source by the law.
It's not the worst idea per se, if done right, and waste separation is actually significant here because it simplifies calorific value control.
When we are not relying on fossil fuels anymore for heat and power (which is hopefully sooner than later), only then we need to start looking into plastic recycling
---
See also: Sweden also incinerates waste for heat and electricity, and a few years ago there was a story about how they ran out of trash and had to buy more trash from their neighbors.
This isn't some theory - right now, today, lost of plastic is being burned, and it works just fine. They try to keep is off the radar because of misinformed people thinking it's bad.
The hydrocarbons are going to get burned one way or another, you can just trade one type for another types.
You cannot replace most oil-based fuel with incinerators. So I'll disagree there.
The utility of oil-based fuels is the energy density in combustion. Burning plastic doesn't come close to the same exchange.
The energy density of plastic (by weight, not volume) is virtually identical to that of oil.
Yes, the machine used to burn oil vs plastic looks different, but coal plants can burn plastic without much modification - and they would be much much cleaner than coal when they do so.
Oil-based unleaded fuel is not oil. You probably could run trains on plastic. That's if you didn't mind hot plastic raining down around the tracks as the coal dust and soot did when we used it for trains.
They burn MUCH MUCH cleaner that coal for example.
> The energy captured from the burn is obviously not the same
There is nothing obvious about it. I don't understand what you mean? Plastics have around the same energy density as oil.
And even in the lofty goal end state of zero fossils, if it's not a complete collapse back to medieval tech (and population numbers), we would likely end up with biomass based plastics serving as packaging and the like at the upper end of that carbon's energy slope, before utilizing the remaining bound energy in an incinerator.
Biodegradable properties of grown plastics are only a last line of defense against pollution when collection has failed.
And if you are proposing the construction of new power plants to burn trash, your justification also has to explain why that would be preferable to building wind/solar instead
An easy to grasp reason is that we still can't viably store energy for long enough periods for wind and solar alone to work. Also solar and wind might not work so well everywhere.
Designer organisms aren't generally well-suited to spreading in the wild and even if they were, they could be engineered to require a certain dependency that they would die without. But yes, still theoretically it's possible.
An enzyme is a protein not an organism
> a flexible membrane (i.e., geo-membrane) overlaying two feet of compacted clay soil lining the bottom and sides of the landfill.
https://www.epa.gov/landfills/municipal-solid-waste-landfill...
I’m not sure if HDPE would make a good liner material or not, but just as an example, the differences in molecular structure between PET and other plastics are big enough that it would take an array of different enzymes to eat them all.
1. https://en.m.wikipedia.org/wiki/Polyethylene_terephthalate 2. https://en.m.wikipedia.org/wiki/Polyethylene
IMO we'd be better off focusing research on reducing the waste rather than improving disposal.
Releasing this into the ocean, in any appreciable amount, seems like a very bad idea. I think collection from plastic "hot spots", and then separate processing, would make more sense. I think it's best to reduce the number of foreign chemicals in the environment.
And IMO there’s much upside to pursue multiple avenues to desired solutions, rather than making choices to eliminate potentially contending solutions too early.
Mother nature herself provides pretty much exactly that template for evolution. So if we want to save nature, why not use that same approach? It seems to have served the survival of life on our planet rather well.
Not to get into tinfoil hat territory, but can any large enough industry be trusted on narratives regarding how waste is handled ?
I don't think there is controversy around landfills leaking. There is debate on wether it's as bad as we think, or the actual impact, but then I find it hard to take a "We don't hear about it in the news, so it's probably fine" stance when we got served BS "we're all in on recycling, don't worry just buy more from us" narratives for decades with almost nothing actually getting recycled.
PS: more on leakage from an industry publication: https://wasteadvantagemag.com/how-much-does-my-landfill-leak...
> As a result of advances in installation quality and CQA practices, leakage rates greater than 50 liters per hectare per day (lphd) have decreased significantly in the past 20 years.
Oh, and why are we still waiting on this: https://phys.org/news/2010-02-spray-on-liquid-glass-revoluti...
Will car plastic interior start to rot?
Will PET soda and water bottles start decomposing in the grocery store, and will they require refrigeration to prevent that?
Will our computer keyboards require new materials?
PET soda bottles will be sterilized, then sealed. The outside is dry and won't decompose. You won't be able to re-close it and leave it out though.
For things that need to stay wet, like drain pipes, you would add chlorine and use PVC which is unlikely to be edible to bacteria.
I'm no expert but given the excess of carbon in the air, it's not out of the question that a viable way forward is actually using more light plastic materials, not bothering with recycling or alternatives (when these are not cost/energy effective), and just putting it in big holes where they will presumable stay unscathed, until (maybe) some day it would be worthwhile to dig them out and reuse the carbon. The whole life cycle is generally carbon neutral, and might even offset more energy demanding alternative products.
I feel that the general aversion to plastic is due to problems that arose more from waste mismanagement that caused the Great Pacific Garbage Patch for example, and not necessarily from the lifecycle of the products themselves.
Do you want to just sequester the Carbon? Something very environmentally neutral would be .... plastic. Anything biodegradable would eventually become CO2 and water.
Best option is to burn it and capture the energy for a useful purpose, instead of letting that energy be wasted when it biodegrades.
The designed enzyme sequence
>contains five mutations compared to wild-type [1]
In this case, the enzyme used as the starting point for engineering turns out to need only a few small changes to improve its ability to efficiently depolymerize PET.
Choosing which of those small changes to make is the aim of the machine learning algorithms the authors used. The authors provide a visualization of exactly where those changes are inside the protein on their website
>Interactive visualizations of MutCompute for Fig. 1 are available at https://www.mutcompute.com/petase/5xjh and https://www.mutcompute.com/petase/6ij6
A pen presumably gets hundreds or thousands of uses, depending on how you count. For example, one way product packaging is much more of a single use plastic.
That being said, I’d hate to lose plastics for bulk food packaging, unless there’s an equally food safe successor.
Not that I'm against finding ways to _actually_ recycle or break-down plastics, just it seems like something we need a microscope to see might be hard to keep track of.
At the very least, I'm sure it won't be as bad as in BioMeat: Nectar.
BBC Science in Action [1] interviewed Prof John McGeehan of the Centre for Enzyme Innovation at Portsmouth University working on Bacteria breaking down Plastic in landfills. He explained his workflow of maybe selecting one candidate very carefully and occasionally out of many due to the cost/time involved & how DeepMind gave him more results in a single weekend (for free) than he had expected to see over his entire reasearch career.
What does that mean?
After reading the article instead of the headline:
They imply they can turn the plastic back into a monomer and then rebuild it as a new polymer. Maybe that would work, but I have huge doubts - a monomer is very chemically active, and it really wants to polymerize. That enzyme may work in a lab, but I doubt they can turn it into an industrial process.
I take issue with this:
"The most common method for disposing of plastic, besides throwing it in a landfill, is to burn it, which is costly, energy intensive and spews noxious gas into the air."
This is utterly false, and I don't see how they can claim to be scientific if they publish falsehoods. It makes me wonder about the accuracy of the rest of the press release.
A fireplace is a smoky thing, without enough air (even the wood makes a lot of smoke). An incinerator makes sure to supply enough air.
On the topic of food waste, my time in the kitchen says most foods will burn just fine. Although, they often leave residues that I could see being problematic when they build up.
As with everything, you'd need specifics to determine the right tradeoffs. It would seem to me there's potential in reducing the transport distance and land use of solid waste, and also reducing extraction, transport, and burning of some fossil fuels, if a burn the trash for electricity program works. But specifics matter, of course.
> which is costly
Burning is not costly it is cheaper than all other methods. It's so cheap it's actually profitable.
> energy intensive
It actually provides extra energy, and reduces energy waste (because now we have to pump less oil.)
> and spews noxious gas into the air.
It spews nothing except water and CO2.
And since we are still pumping oil of the ground, leaving a different form of oil (plastic) in the ground doesn't accomplish anything useful.
I'm not sure what distinction you're trying to draw.
>And since we are still pumping oil of the ground, leaving a different form of oil (plastic) in the ground doesn't accomplish anything useful.
I suspect that overall energy production in the US probably emits less CO2 per kwhr than burning garbage does, so starting to burn garbage for energy would be, in that regard, a net negative. Furthermore, it would likely require moderately significant capital expenditure that could've instead been used for something better.
It spews NOx and the whole bunch of undesirable things like dioxines.
You don't get pure PET and oxygen in, and you don't get pure CO2+H2O out.
It's messy to the point that it's debatable if it's better just to bury it.
> It's messy to the point that it's debatable if it's better just to bury it.
No, it's not. You do get that people are doing this already, right now? It's not some theoretical - there's a huge amount of plastics being burned, and it's very clean.
Why is it so common for people to pretend to be environmentalists and advocate for things that directly harm the environment?
who is "we" here ?
> to pretend to be environmentalists
that is wildly defamatory, with no evidence, right?
> that is wildly defamatory, with no evidence, right?
The evidence is right on their own website. Their advocacy that they are so proud of is actively harming the planet and they are sitting there proud of it.
Obviously we want plastic to eventually biodegrade, but I wonder what sorts of chaos would be caused by it.
Plastic bottle recycling into new plastic pellets works quite well. Southern California has a huge plant doing it. Non-bottle plastic is more of a problem but less of the volume.
There is such thing called second law of thermodynamics.
The only question is into how much stages we can split this process, and how much useful stuff we can extract from each of those.
Right now the only solution is to minimize plastic use as much as possible. Please keep this in mind.
with the idea that the public will feel better about all the plastic that is being thrown into the environment and landfills.
Personally, I don't think it's anywhere as much of a problem as the environmentalists claim it is either. Much like the biomass from long ago which has become the oil of today, I'm pretty sure the plastic waste of today will simply become the oil of the future.
OK, but on that timescale virtually nothing about climate change or environmental issues matters. On the scale of millions of years, life on Earth will continue in some way or another. But what's important is how much suffering will be endured in the potentially cataclysmic coming 100 years, and plastics hold great potential for harm on that timescale.
I don't think plastic eating bacteria would be as much of a problem as people make it out to be.
I assume nothing will happen while this "news" will be used by fossil fuel companies to virtue signal "technological progress" in the plastic problem.
Seems to be one of those things where, if you're not in the field, all the news is the same and sounds like a breakthrough, but it'll be 20y out from actual adoption for a while.
Everyone wants a quick fix for climate change and pollution because it will absolve us of doing the hard work that the problem really requires. By all means, we should pursue such moonshot ideas - but like you said, it will be used to virtue signal some false idea of "progress" while the problem gets worse.
But it's definitely worth exploring those moonshot ideas, so I'm not shutting that idea down. It's just good to be aware of how these sorts of headlines are used in the service of greenwashing.