Claim: Greenhouse gases linked to degrading plastic

Several greenhouse gases are emitted as common plastics degrade in the environment, according to researchers from the University of Hawaiʻi at Mānoa School of Ocean and Earth Science and Technology(SOEST).

Mass production of plastics started nearly 70 years ago, and the production rate is expected to double over the next two decades. While serving many applications because of their durability, stability and low cost, plastics have a negative impact on the environment. Plastic is known to release a variety of chemicals during degradation, some of which negatively affect organisms and ecosystems.

What happens when plastic degrades?

The study, published in PLOS One, reports the unexpected discovery of the universal production of greenhouse gases methane and ethylene by the most common plastics when exposed to sunlight. The SOEST team tested polycarbonate, acrylic, polypropylene, polyethylene terephthalate, polystyrene, high-density polyethylene and low-density polyethylene (LDPE)—materials used to make food storage, textiles, construction materials and various plastic goods. Polyethylene, used in shopping bags, is the most produced and discarded synthetic polymer globally, and was found to be the most prolific emitter of both gases.

The team found that the emission rate of the gases from virgin pellets of LDPE increased during a 212-day experiment, and that LDPE debris found in the ocean also emitted greenhouse gases when exposed to sunlight. Once exposed to solar radiation, the emission of these gases continued in the dark.

“We attribute the increased emission of greenhouse gases with time from the virgin pellets to photo-degradation of the plastic, as well as the formation of a surface layer marked with fractures, micro-cracks and pits,” said lead author Sarah-Jeanne Royer, a post-doctoral scholar in the Center for Microbial Oceanography: Research and Education (C-MORE) during the study. “With time, these defects increase the surface area available for further photo-chemical degradation and therefore contribute to an acceleration of the rate of gas production.”

It is also known that smaller particles, termed “microplastics,” are eventually produced in the environment and may further accelerate gas production.

Connection to global climate change

“Plastic represents a source of climate-relevant trace gases that is expected to increase as more plastic is produced and accumulated in the environment,” said David Karl, senior author on the study, SOEST professor and C-MORE director. “This source is not yet budgeted for when assessing global methane and ethylene cycles, and may be significant.”

Greenhouse gases directly influence climate change—affecting sea level, global temperatures, ecosystem health on land and in the ocean, and storms, which increase flooding, drought and erosion.

“Considering the amounts of plastic washing ashore on our coastlines, and the amount of plastic exposed to ambient conditions, our finding provides further evidence that we need to stop plastic production at the source, especially single-use plastic,” said Royer.

Royer is now working to develop estimates of the amount of plastic exposed to the environment in oceanic and terrestrial regions, globally, in order to constrain the overall greenhouse gas emissions from plastics.

Advertisements

62 thoughts on “Claim: Greenhouse gases linked to degrading plastic

  1. “Royer is now working to develop estimates of the amount of plastic exposed to the environment in oceanic and terrestrial regions, globally, in order to constrain the overall greenhouse gas emissions from plastics.”

    So he has at least two decades to estimate the amount. Nice work if you can get it.

    • Sarah-Jeanne is probably a she. But yeah, if you’re a post-doc oceanographer, where you gonna go for the funding gravy train? All the fun projects have been taken— like sedating fish and observing that it makes them sluggish.

      This is kind of a second order effect. First the watermelons set their sights on having an excuse for why we have to stop burning fossil fuels (because capitalism depends on them and the real goal is socialism through the back door). Now that they have their mythology fully developed, we see the phenomenon of trying to attribute GHG emissions to anything that they want to eliminate like the use of plastics.

      It’s a sign that the CAGW religion is matuing and developing doctrine. “In the beginning, CO2 warms the planet”. GHGs are like fallen angels that mediate Climate Change (TM). But now we are hearing debates that presuppose the reality of angels and have moved on to speculation of the number of angels that can dance on the head of a pin.

      Kristi disclaimer – there is no conspiracy at work here. Each individual perpetrating this false doctrine is acting on their own interests independently. Yes, the socialists push it to destroy capitalism. But the others may not be motivated at all by a desire for socialism. The researchers genuflect to it because they need funding to put bread on the table. The politicians professs it because it is an opportunity to expand government with them in control. The big corporations swear fealty to it because it is an opportunity to farm goverment subsidies instead of doing real work producing real value with competitors cutting into the bottom line. Many a cynical celebrity virtue-signals their faith in CAGW because it maintains their image, but lives as if they are well-aware that it’s a crock. Most of the ordinary folks who still profess the lie are kind-hearted and sincere, but are deceived.

      • with a statement like this:-
        “Considering the amounts of plastic washing ashore on our coastlines, and the amount of plastic exposed to ambient conditions, our finding provides further evidence that we need to stop plastic production at the source, especially single-use plastic”
        I would say that all her scientific impartiality has flown out of the window.

        From a purely plastic pollution point of view she would have a point but from a greenhouse gas point of view she is clutching at very small straws!

        • I would say that by all means we should find out who is discarding of these items improperly, and stop them from doing it.
          Paper and cardboard and wood break down too, into a greenhouse gas…so we better stop using them…or maybe just stop the bungholios who make huge messes from making huge messes.
          But the obvious implication is that these materials are evaporating and the evaporation accelerates as the process continues.
          So there is no emergency…just messes to clean up.
          We should be reusing or burning it for fuel anyway.

          • But isn’t it a good thing that the carbon is sequestered away in a form that’s not increasing the warming? We need more paper, more plastic, MORE STRAWS!

        • Mark Hansford : “she is clutching at very small straws!”
          THAT could be a good result……..since “THEY” are banning plastic straws !!!!

      • RICH : “Sarah-Jeanne is probably a she.”
        THAT is VERY presumptive of you !!!!!
        In this POST-MODERN era , where genders do NOT exist and
        NOTHING can be known for certain and “facts” are merely arbitrary ,
        such CERTAINTY on your part is BOUND to OFFEND someone sensitive , somewhere!
        Sarah-Jeanne ALREADY has enough to suffer without being stereotyped by you !
        I think MASSIVE APOLOGIES are in order , don’t you ????? ( ***SARC ! )

        • In fairness to me, Trevor, I made a diligent effort to determine which pronouns “they” “identify with”, but I had to fall back on the linguistic proxy of French declension and Aramaic etymological determination. In layman’s terms, I am identifying this morning as far too smart to admit to any degree of error or uncertainty. Man may be he/him/his. What is it for Mann? (I feel that I’m mannish today).

  2. So these plastics are a threat to marine life because they do not degrade and a threat to the environment because they degrade. Plastic have an energy potential. A more useful area of research would be to breed plastic eating plankton.

  3. A complete joke of course! We ALL know that plastics degrade in the environment thanks to solar radiation & bacteria. Yet the fanatics at the BBC and elsewhere have been banging their drum to ban plastics for ages now, especially after their Blue Planet series. They claim that plastics are “forever” or that they break down only over long time periods into microplastics that poison marine life! They have whipped up a firestorm against plastics, one of the most useful families of polymers man has ever created. Now, we have the flip side argument – degrading plastics produce CO2, methane, etc!

    Are we surprised? NO! Plastics are made from long chains of carbon atoms with hydrogen and a few other things stuck on. When they degrade, like leaf litter and many other natural organic wastes, they produce CO2 and a few other minor things! GASP! SHOCK! HORROR!

    But you can’t have it both ways – either they don’t biodegrade, stick around forever and don’t generate CO2, etc….or they do biodegrade and disappear!

    We know the answer already! However, the amount of plastic in the environment and the CO2 generated by its decomposition is trivial compared with other perfectly natural sources of those same gases from decomposing leaf litter and other plant waste.

  4. Didn’t test PVC, the most common plastic in construction. That’s because it’s easily UV stabilized. But they wouldn’t mention that for fear of promoting the evil PVC industry!

  5. Yeah, that’s right. And doesn’t ethylene cause guys to turn into girls. Thus plastic pollution is part of the feminist conspiracy to rid the world of men.

  6. In other news, it’s been rumoured that the sun rises in the East.
    Watch out for TV bimbo, under a cloudy sky, doing a breathless piece on the lunchtime news

    But wait, what if there was/is an oxidising agent in the vicinity of these degrading plastics and some the stuff coming off them was turned straight into carbonoxide
    I wonder what that might possibly?

    (Stern voice coming off Peta’s shoulder reminds that these people are entirely paranoid and it is NOT a good idea to ‘give them ideas’)

    Peta goes where fools fear to tread (has been spotted recently in E London) – What if there was some REALLY potent oxidising agents around, nothing like ozone or nitrate by example.
    Ozone, as made via the action of UV on diatomic atmospheric oxygen.
    Nitrate, coming from nitrogen oxides created inside thunder storms.
    And burning stuff. Fires here there and anywhere. They all create nitrate.
    Baby & Hosch do NOT have the monopoly on nitrate.

    Hang on another minute, didn’t someone once describe cellulose and lignin as ‘plastics’?
    What about fats & proteins as make up any and all Life on Earth?
    Are they not just variations on ‘plastic’

    Is it inconceivable that all the dead plant material modern farmers create (agricultural waste – a true oxymoronic idea if ever there was) might being oxidised thus?
    What about the (literally) countless trillions of soil bacteria they are constantly digging up with ploughs and other cultivation equipment? Instantly dehydrated (killed) then blown to complete buggery by UV and oxygen. Where do they go, what do they become?
    Surely not carbonoxide?
    Why did Ma Nature invent annual plants – with seeds that can remain dormant for decades & centuries yet can triggered into life by a split second of exposure to sunlight.
    What exactly are *they* all about?
    Possibly to rapidly ‘protect the soil’ in the event of accidental exposure to the sun following fire or storm

    Hang on again, what is sunburn all about? Is this not the destruction of actual living cells, fats, proteins and sugars by strong sunlight?
    Hello Sarah Jeanne, you should know this being nicely tanned – the sort of sun one may find in either Barcelona or Hawaii as per your CV
    (What sort of education did this girl get, how *did* she get to be a PhD)

    Nothing’s simple is it – EXCEPT when you are trapped inside Magical Thinking of your own doing and endlessly reinforced by those around you – your ‘Peers’ and ‘The Consensus’

    • “In other news, it’s been rumoured that the sun rises in the East.”

      That’s only if you are in the west. If you go far enough east, past where the Sun rises, you will see it rise in the west.

      • Well.
        Ish.

        [It is noted that if you are on a Concorde, (a famous Anglo-French SST, not yet matched by our N American colonies) and travelling west very – very, VERY – quickly, then, yes, the Sun will rise in the West (as you catch it up!).

        Auto

  7. In my secret laboratory at home, my research team had discovered that even an ostensibly harmless activity such as ‘making a cup of tea’ can produce large amounts of the strongest greenhouse gas of all. We have repeated this activity many thousands of times with the same result. We are doomed! Unfortunately, I forgot to submit an application for a research grant to cover this work so that I could live comfortably on other people’s money. Contributions would be welcome (Earl Grey or Sterling preferred).

      • Good point. Roasting coffee beans throws off large volumes of organic gases. There’s no doubt but that each and every one of them has a significant global warming coefficient of CO2-equivalence.

        Likewise, fermenting tea leaves to make black tea produces considerable AGW-worthy gases, including aldehydes (known to be allergens and cancer-inducers).

        The black teas themselves have upwards of 200 volatiles. Global warming producers, all; no doubt about it.

        There’s a clear opportunity in all this for the career enhancing trait of environmentally concerned and virtuous scientist plus the necessary modern attribute of saving Earth for the children.

        Today, it’s plastic. Coffee and tea await as immediate opportunities for the forward-looking environmental scientist.

        And after that, bread! With more than 540 volatiles, bread baking is ripe for planet-saving elimination.

  8. If they are right, and they probably are, this serves to reinforce the argument for the disposal of plastics by using them s a fuel for the generation of power. If they inevitably give off methane, ethane (and probably CO2), rather than just let them waft into the atmosphere we should harness them as a fuel source. This they way they will mitigate to burn other fuels.

  9. Who is throwing all of this plastic into the ocean? Let’s find the SOB and stop him/her. Single-use plastic has made an improvement in maintaining the sanitary condition of food. Seriously, where is all of this plastic debris coming from? Reminds me of the protest camps after they leave and must be cleaned up.

    • According to the graph in a very recent WUWT post (data from the Wall Street Journal), annual amounts from China is 8.8 million metric tons, Indonesia is 3.2 million and the US just 0.3 million.
      The vast majority of ocean plastic is emitted by the developing world, where there is strong economic growth but also relatively weak environmental regulation.
      Chris

    • Ron – a suggestion: don’t let them leave the protest camps until they have cleaned up and left the sites as they were before they assembled. Who could object to that?

      • The oil companies that they are protesting against have to return the land to “as good or better” condition than when they arrived. Why are the protesters not held to a similar standard.

        Note: I know that oil companies were not always held to this standard, but they are now. They even have to post a bond to protect the environment against the potential of the company financially failing.

  10. Stop dumping plastics in oceans and open countryside is a good thing without the trivial and unimportant emissons of gasses when they are broken down by the environment.
    A sophisticated serious study would piint out the offsets of plastic against enviro destruction that plsstics prevent.
    But we are dealing with a climate hype paper so that ain’t happening.

  11. Once greenies realize that banning single-use plastic will mean replacing it with paper, and that will require putting loggers back into forests and the resurrection of failing pulp industries, the plastic bans will quietly be set aside.

    When it’s distilled to its basic form, greenism isn’t really about saving the planet, it’s about stopping capitalism.

  12. These people who complain the loudest are those who use PLASTICS the most.

    Simplest solution is to remove plastics of all kinds from their vicinity, especially credit/debit cards, and make them revert to an entirely non-plastic world. That means no WiFi/IT or any electronics of any kind, period, nothing even vaguely touching plastics. Zip. Zero. Nada. Live the way our great grandparents did. In fact, any synthetic materials generated by modern industries should be forbidden to them. Anathema, you know. They’ll have to use REAL money, drive 1970s Oldsmobiles, use paper bags at the grocery stores, and store everything in glass and metal.

    Then we’ll see how sincere they are about their complaints.

    I doubt they’d last five minutes.

    Did the format of the page change? It is all spread across the screen, with none of the sidebar stuff. Maybe it’s just at my end.

    • That means no WiFi/IT or any electronics of any kind, period…

      I beg to differ. You can do plenty of electronics without plastics – plastic just happens to be a convenient insulator/dialetric. In fact, the early development of electronics preceded industrial plastics.

  13. All these man made “plastics” came from sequestered Fossil Fuels that were modified. Now as new forms of sequestered Carbon, they are being returned to the Earth where they came from, as they deteriorate back into the environment over many decades. I’m all for increasing the Carbon back into the environment, that all life forms require to live. But, this garbage is a problem when it harms more life forms due to its shapes that dumb animals cannot deal with. The problem is, that the so called smartest animals are the idiots that have created this problem.

    We now know how much of a fallacy it is to recycle these plastics are, cost and man hours it takes for a deficit of return. When just burning them as fuel to generate electricity is more effective. Even the byproduct of soot reintroduced with oxygen from air burns like clean coal. Sure, sulfur and other elements are in plastics – that create stronger greenhouse gases – but the amount is small and can be scrubbed.

    Somehow I see Wall-E running around gathering plastic in a world of garbage. Mankind is a very wasteful creature of habit. And I don’t hope for Dr. Emmett Brown to come up with a garbage powered DeLorean any time soon. At some point you’d think a small home device could be made to burn your garbage to power some appliances. It amazes me how twice a week I have to take out the trash with just my wife and I here.

      • Back when I was in college, a friend of a friend used to sign up for every magazine and flyer he could. When they came, he tied them into tight bundles and burned them for heat.

  14. If we didn’t use plastic, we’d use something else, and they’d complain about that.

  15. well didnt the plastic hate spring from nowhere real fast?
    guess the frustrated agw crowd needed something to do

    • The Left is incredibly organized. I think every day or two there is a APB giving out the newest talking points. I saw an instagram post that showed hundreds of local news broadcasts from around the country that each appeared to be reading an editorial written by the local news anchor, but they were all the same, word for word. And not all the same network.

      They are well organized, and intend on destroying our prosperous western civilization.

  16. In CaliPornia, used PLASTIC needles are O.K., Human feces and urine on sidewalks are O.K., but PLASTIC straws,,,,,, OMG, the world is going to end !!!

  17. This statement “our finding provides further evidence that we need to stop plastic production at the source, especially single-use plastic,” said Royer.” is activism not science. The findings are not evidence of any such thing.

    They are evidence that:
    1. The anti-plastic activist meme “Plastic are Forever” is nonsense, as I have written before.
    2. Plastic breakdown produces the simple, natural gases already produced as part of the normal carbon cycle by plants and animals: methane and ethylene. Methane we are all aware of (often unpleasantly aware of its natural production) — ethylene is produced and used by plants as a natural hormone and a biological signal for ripening of fruit, production of flowers, and many other things.
    3. This study is evidence that the breakdown of plastics do not produce “franken-chemicals” that are scary and dangerous.

    • “Considering the amounts of plastic washing ashore on our coastlines, and the amount of plastic exposed to ambient conditions, our finding provides further evidence that we need to stop plastic production at the source, especially single-use plastic,”

      Good luck with that one! Tell me you are going to stop China from producing plastic. Then tell me you are going to stop consumers from preferring cheap stuff.

      What percentage of plastics end up in landfills, is recycled, or is left exposed to sunlight? Are we recommending banning single-use items (e.g. straws) because a small fraction does not find the trash container or recycle container? Let’s promote proper waste disposal and recycling.

      I know enough about plastics and biodegradation to realize how much I don’t know (Thesis subject: epoxy metal-ion polymers plus many years work experience with destruction of chlorinated solvents in groundwater using specialized bacteria). Despite what I don’t know, it does stand to reason that if recalcitrant organic compounds such as clorinated solvents can be degraded by bacteria, non-recalcitrant compounds should be easier to degrade.

  18. Well, just lately, the eco-loons have been upping their attacks on plastic, so they need some ‘studies’ to cite to justify it all.

  19. Same old same old.
    One minute plastics allegedly don’t degrade in the environment, a minute later they allegedly cause a problem when they do degrade in the environment.

    And the alledgers are wrong on both counts, as usual.

  20. So they have discovered the obvious…that when plastic degrades, which it does, it is broken down into it’s constituent monomer subunits.
    IOW…it evaporates.
    It is also a food source for a growing number of bacteria…which have evolved the ability to eat it after only a few decades…an evolution that we can expect to continue and to accelerate, knowing as we do that bacteria share genes even with genetically unrelated bacteria.
    And instead of declaring the fake emergency of “plastic is forever and buried stuff that stays the same really troubles greenies” to be over…they use it as yet another reason to say we have to stop using plastics to make our lives better and more convenient.
    Plastic degrades and so eventually it will all just be gone…the opposite of what these loons insist will happen to it, and that idea that it is forever is why we had to stop making and using it to begin with.
    So now that this is known to be false, instead of declaring the emergency to be a false alarm, they of course double down on it, because “it may be significant”.
    Krikey!
    Just shoot me now!
    Better yet, not me…

  21. I would imagine this is true. As Hydrocarbons breakdown, it would follow that CO2 is emitted. I’m confused why SOEST thought this was news. Same applies to biodegradable product (like paper straws), or even compost.

    Even trees, when they die and decompose, they release CO2. Better to sequester that carbon by turning them into paper or houses.

  22. Question: does anyone have the information for methane and other gas production for the degredation of an equivalent volume of wood? Second, ethylene is a Highly Reactive Volatile Organic Compound. It’s global warming potential is essentially zero because it has such a short lifespan. Less than a day. This would exacerbate smog, and it does make an argument for landfill gas control, but that’s a completely different topic.

    • In principle, after hydrolysis, cellulose can be broken down by anaerobic fermentation into just CO2 and methane thus C6H12O6=3CO2 + 3CH4. So very roughly about 1/3 methane by weight from the cellulose component of wood. (Lignin is a different matter).
      In practice varying amounts will be obtained, the amounts depending on the bacteria, temperature, the amount of oxygen and other compounds present and, ….a whole host of other factors which can lead to many different products such as carboxylic acids (peat bogs are naturally acidified by such processes).

      There is still a lot of money waiting for the person who can develop an efficient industrial process that works at ambient temperatures. The multi-step natural process is still agonizingly slow (by human standards and needs) for something nature has had so long to work on. It’s the sort of thing global-warmers should really be spending their time on if they were serious about science and not averse to a bit of enzymology and genetic engineering. That’ll be the day.

  23. Well, duh! Plastics are organic compounds, mostly made of carbon. They are a good form of Carbon “sequestration”, especially the non-degradable ones. MORE STRAWS!

  24. This contretemps among the environmentalists, on whether plastics breakdown or last half of forever, is going straight into a large file I keep called the Confused Environmentalist.

  25. Not really sure if mankind ever actually lived in caves for any appreciable period of time, but if the socialists, ‘environmentalists’ and other assorted leftists get their way, we will all be residing in caves or mud huts living like ignorant animals without their advantage of instinct to guide them and with no modern conveniences. Living meager, mean, dirty and short lives is apparently what they have in store for us. Kinda like Venezuela I guess.

Comments are closed.