The article talks about using it for environmental cleanup, but the paper seems more focused on recycling back into fresh PET[0]:

> ...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.

[0] https://www.nature.com/articles/s41586-022-04599-z

I used to think burying plastic in landfills for carbon sequestration was a good idea. Then I found out that making plastic releases an enormous amount of CO2.

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.

Yeah, landfills are not major environmental problems, AFAIK, but they offend the neat freak within all of us.

And, as you say, they're pretty good carbon deposits, which is supposed to be The Most Important Thing.

I think the main problem is that the average Joe/Jane confuses all types of pollution as equally bad. The real, most imminent threat is really CO2. That's what we have to spend the most money/energy on, because it could have absolutely catastrophic consequences in the next few decades.

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.

Sperm counts have been dropping for a long time (50%-60% over the past 50 years) without stopping, and plasticizers are the suspected culprit. It's incredible how many people need to do IVF now. I would argue that might be the most imminent threat but nobody seems to care.

> Sperm counts have been dropping for a long time

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.

I'm certainly no expert, but from what I've seen the scientists are pretty firm in their belief it has nothing to do with obesity or other societal factors. Most of those are fairly easy to control for.

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.

Just to remind everyone, the decline in sperm count is across species, not just in humans.

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.

The need to do IVF is also related to women marrying and choosing to have children later.

People should have fewer kids anyway, I see this as an absolute win.

Speaking as someone that had to go through IVF, that's a bit like celebrating cancer for reducing the population. Infertility is devastating for you and your relationship when you want to have children.

Don't expect empathy from someone who has found the Rightful Cause(TM).

You have my sympathies for going through a this procedure even though I never had to do that.

Infertility would be "none", and I didn't say that, I said "fewer".

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 misanthropic and belittling?

I'm neither of those things now, nor am I always anything.

Are you always this antagonistic and reductive?

When someone infantilizes or shames people for their suffering, yes.

Considering I did neither of those things, your behavior remains unexplained...

Large majority of developed countries are below replacement rates, so there's no need to gloat in the suffering and pain of people who can't have children.

Why yes, just commit demographic suicide à la Japan.

What an anti-human stance.

Garbage is also a problem in the environment like plastics in oceans, but the problem is not enough (well run and used) land fills (in Asia) not too many!

50% of the plastic problem in the ocean is discarded fishing nets (generally accepted to be discarded from Asian fishing vessels).

Source?

A more accurate claim: 46% of the mass of the Great Pacific Garbage Patch is fishing nets.

https://www.nature.com/articles/s41598-018-22939-w

Plastic pollution of oceans is much much bigger problem than just pacific garbage patch.

looks more like 10% [0]. but it depends on where in the ocean you're talking about - they float more easily than a lot of plastic, and so are caught the pacific gyre.

[0] https://www.greenpeace.org/aotearoa/publication/ghost-gear-t...

Don't forget methane! It is 80x more potent (eventually degrading to CO2 in the atmosphere)

We leak it all over the place, with no plans to plug the holes. Instead we keep adding new piping all over.

"decarbonization" is a bad term. CO2 is the problem.

> Also, the very premise that more CO2 is existential is contradicted by historical record: 250 million years ago earth was 15 degrees warmer than it is now and CO2 was a lot more abundant.

Maybe this is just a joke that sailed over my head, but this is obviously false and doesn't mean anything of the sort. Existential for whom? All you can definitely conclude is that the Earth won't explode if the climate increases by 15 degrees. You can guess that life would survive, but there were no humans back (or large mammals at all) back then. There's no reason to think we would make it.

> The people controlling the media won’t allow it. This is common knowledge.

This is just rank conspiracism. I know of no evidence to suggest that the media are somehow controlling events (?), laws (?), the "narrative" (?), simply to prevent nuclear reactors from being built. How? For what purpose?

And claiming "this is common knowledge"? Maybe that was just another joke, because normally when one says a conspiracy theory is true, one also claims that this is secret information that has to be carefully mined out of various data sources, because if everyone knows something is happening it's usually not a very good conspiracy.

> simply to prevent nuclear reactors from being built. How? For what purpose?

If a country has sufficient nuclear energy then they are immune from international energy politics.

Two, I see that the oligarch class is using global warming alarmism as the driving narrative to move everyone to a carbon credit system, where payouts go to an unaccountable transnational elite.

Ironically, I believe that once the incentive structure is in place, there will be institutional force to keep you buying carbon (offsets) credits… forever.

The Earth will keep spinning round no matter what. It is ourselves who we harm

We see animals and people living with 15 degrees spread now. That won't change.. people and animals would exist at 25 degrees. Not as many and not in all places.. but we can be sure humans will survive somewhere aided by technology.

This is a striking example of what I've observed in many places which has often made me wonder why the intersection between nuclear advocacy and some form of climate change denialism is so large? The inconsistency is odd: "I passionately believe we should be using nuclear power to solve a problem I don't actually believe is a problem".

Eh it's probably just a version of "owning the libs". By and large the leftist environmentalists and "tree huggers" are anti-nuclear, so you basically annoy them in two different ways.

People believe if you truly care about reducing CO2 not using nuclear means you will not be able to move off of fossil fuels until we are well past too late.

It's the flaw that makes reducing global warming a talking point vs an actionable item. It's a big elephant in the room.

Until that gets resolved many will think some are spinning your wheels.

Nuclear fuel must first be mined, correct? That's not renewable and could offset the benefits somewhat. That said I imagine it may be better as a base load than dirty coal.

> That's not renewable and could offset the benefits somewhat

I don't think you realise the VAST amount of energy density in one 1kg of coal vs 1 kg nuclear fuel. "Somewhat" is not nearly the correct comparison !

"8 kWh of heat (energy) from 1kg of coal vs 24,000,000 kWh from 1 kg of uranium-235" [0]

[0] https://www.euronuclear.org/glossary/fuel-comparison/

Does that mean 1 tonne is enough to power the world for a year?

As far as I know that's pretty much exactly the amount of fissile material used annually world-wide.

The caveat is of course that for 1 kg of coal you have to dig up a lot less material than you have to for 1 kg of fissile material - U235 is around 1 % of natural Uranium, and Uranium is around 1 % of the ore.

Solar panels require minerals that must be mined too. Batteries are an even greater abomination.

Nuclear waste is also extremely compact.

Unfortunately our world is not run without the consumption of resources. There are trade offs to everything.

We’re not running out of fissionable material any time soon

What are the limiting inputs? Because I imagine there is a lot to do to go from the ground to the reactor and back again?

Breeder reactors produce more fuel than they consume.

Wouldn't that violate the second law of thermodynamics?

It isn’t creating more energy, it is just converting non-fissile material to fissile material

https://en.wikipedia.org/wiki/Breeder_reactor

But we don't build breeder reactors. For reasons.

The real threat is the nearly 1 trillion tons of toxic waste we're racking up PER YEAR. It's the most lethal stuff this planet has ever encountered.

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.

I haven’t heard this before. What kinds of toxic waste are you talking about?

Radioactive, dangerous chemical, ...

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.

You're still not saying what it is that you're talking about.

The best thing to do for both of those is shut down coal plants; the emissions from those are terrible for health and they’re even radioactive too.

In a way radioactivity is one of the easiest contaminants to deal with: Instant, contact-free testing for levels is trivial with cheap, handheld devices, compared to virtually all other toxic substances which usually require taking samples and analyzing them in a lab. Decay is very well understood and easy to characterize.

The area around Chernobyl is very green and many animals live there. Things survive..

> The area around Chernobyl is very green and many animals live there. Things survive..

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...

No one said safe for humans for hundreds of years. But life survives..

Well, it's easy to say if you don't live near one.

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.

I wouldn't go that far.

> 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....

Sure. That's almost all due to food waste, though. FWIW.

https://www.epa.gov/sustainable-management-food/sustainable-...

Yes, for that reason Santa Clara County (Silicon Valley) is pushing hard to divert food waste out of the garbage and get it composted instead: it's supposed to go in with yard waste, not the regular trash. Not sure how successful this is as it counts on people putting things in the correct bin.

As a county resident, I also started doing this recently, and I am amazed how much organic waste we were throwing away previously. My regular trash can takes much longer to fill, and I am constantly taking out the little kitchen bin (that was provided by the waste company).

Diverting compostables out of the regular trash stream also makes the regular trash stream not stink. My under counter trash bin can go two weeks easy without stinking up the place. It is mostly plastic that can't be recycled.

There is a program like that in some suburbs of Sydney. We get little green bags for compostable waste. The up take has been ok from what I’ve seen but these are affluent suburbs.

Here in the UK you can actually be fined for putting food waste in the regular bin (although that depends on where you live and enforcement is spotty).

We are now able to do this here in suburban Los Angeles. You can now put your food waste in the bin meant for green waste (lawn clippings)

Composting is good, but it's heavy and hence energy inefficient if it's transported too far. This goes for almost all waste but the amount of water in compost and the transport distance adds upp. Handling waste and composting as local as possible is important.

The US sends millions of tons of trash to China, India, and other places. Perhaps it would be better for places to implement local sorting (glass, plastic, paper, etc.) and composting- as many other nations do as opposed to disposing of all trash in the same containers and shipping the problem off for someone else to deal with. But even better would be to generate less trash in the first place or at least have an attempt at transitioning to using biodegradable packaging. Packaging, which also is excessive and unecessary in the first place, like items in layers of plastic casing, plastic boxes, plastic wrapping, and so on when there are ways of distributing goods without convenient prepackaging in favor of instead refilling reusable containers or utilizing materials such as fabric, glass, or others which can be repurposed and reused more flexibly and reliably than plastic.

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.

> Yeah, landfills are not major environmental problems

... yet?

What would cause them to be an environmental issue? As far as I know they can be built in a safe manner and there is plenty of space for them.

Most landfills contain icky things like heavy metals or arsenic. Having that leak into an aquifer Would Be Bad.

That’s why they’re sealed with clay and plastic and constantly monitored for leakage.

If it needs constant monitoring it's a potential problem... And at some point it will happen... We know that from ages of software development, if it can fail, it will fail at some point.

You’d be surprised by the number of things that need to be constantly monitored. Building structures, power plants, roads, dams, mass transit, etc. basically everything.

Dams break and wreck havoc on ecosystems, the US has had it's fair share of coal mine sludge disasters. Even countries with strict environmental agencies and long history of mining have accidents.

So what's your solution? Stop building dams and decommission the ones that have been built? Humans attempt to create order. The universe naturally wants to increase disorder. It's natural that anything we create will need to be monitored.

We know that dams are dangerous and that they fail, the smaller ones are decomissioned when not in use not only to improve the ecosystem. A dam is not designed for a life of a 100 thousands years, it's a long time.

In the Western world maybe, but outside of it... hell even in the Western world we have regular reports of mismanagement and corruption, just look at Italy.

We need to reduce the amount of trash we produce, not hope for a miracle technology.

Landfills are not a miracle technology. They exist already and are technologically sound. It’d be way more of a miracle if we somehow managed to greatly reduce waste.

People love to "what if" landfills. Best to not bother arguing with them. We have tons of problems with emissions, plastics pollution, industrial dumping. However landfills ain't one of them, but people won't give up. I've learned to not bother discussing anything with them if they don't know a few basics of how modern landfills are run (at least in western nations).

As others have mentioned they are a major source of methane emission, though this can be addressed (do a better job separating out food waste and compost it).

Landfills were demonized for a long time because they were easy targets.

It's usually just disguised NIMBY-ism :)

The thing about nimbyism in this case is that confortable commentators on hackernews are vanishingly unlikely ever to have to live near one. This is a poor people problem.

There’s a famous landfill right in Silicon Valley though; it’s caused Milpitas to smell like rotten eggs for the last 20 years.

https://sf.curbed.com/2019/3/19/18273029/milpitas-odor-studi...

Correct, landfills are not a miracle technology. Landfills leak.

https://www.clf.org/blog/all-landfills-leak-and-our-health-a...

https://pubs.usgs.gov/fs/fs-040-03/

How sustainable are landfills? There's limited land for farming, residences, manufacturing, and everything else we use it for. And trucking trash to deserts to landfill there isn't carbon neutral either. Trash also doesn't breakdown as quickly in covered landfills (for better or worse depending on what one dumps).

Given the yield of useful content vs. rock in mining, I suspect the more limiting factor is space for all the mining, not space for disposal of the 0.1% metal etc yield for making industrial goods.

If you are worried about space i recommend that you look at the surface area of earth and the volume of space that’s accessible to us underneath the surface.

Is there enough raw material on earth for landfills to become major environmental problems? (genuinely curious)

Depends what you mean by "major environmental problem". Landfills aren't going to singlehandedly cause anthropogenic climate change, but they contribute significantly to it, and a poorly sealed landfill leaching its contents into the local water table can cause some pretty drastic problems with the local environment

How are they worse than any alternative? If I dump my food waste in the garden, is that emitting less GHG than letting it decompose in a landfill?

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.

Maybe this makes me sounds like a jerk, but:

All material that can end up in landfills is already on Earth.

Or those of us who don't like microplatics in our fish, water, and bodies

Those microplastics aren't coming from landfills. They're coming from your everyday interactions with plastic and people dumping plastic in rivers and oceans.

Maybe not the landfills once they are buried. But certainly from waste transfer stations or unburied waste, seagulls and other birds will pick up trash because it smells like food or may have some food in it, and then drop it outside of the landfill/transfer station.

If you don't like microplastics, then you should be pro landfill.

A very large fraction of those are from plastic waste in Asian countries that gets dumped into waterways instead of being landfilled.

I would infinitely rather have a bit more gaseous carbon than a 10,000 year source of endocrine disruptor microplastics leaching into the water.

It's a good thing we're all rich here, able to move to places with better climates or buy air conditioners, not the billions of poor people who have no way to survive intensifying extreme weather events.

Plastic production worldwide is 300 million tons. I am not sure how this would convert to tons of CO2 as it burns (each carbon in the polymer chain associates with more oxygen in the air so it becomes heavier) but the world's CO2 emissions are 30 billion tons, so this would be in the order of 1 to 3% of the whole world's emissions.

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).

> 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.

yes! American do not need worry about typhoon, so I can understand why there are so many people trust global warming can made environment "better"

hey did you know plants absorb c02