Plastic Watch: Debunking the Technofix Fairy, Biodegradable Bags Don’t Degrade

By Jerri-Lynn Scofield, who has worked as a securities lawyer and a derivatives trader. She is currently writing a book about textile artisans.

‘Biodegradable ‘ plastic bags were still intact and capable of carrying shopping three years after being exposed to the natural environment, according to a study published this week by scientists at the UK’s International Marine Litter Research Unit, School of Biological and Marine Sciences, University of Plymouth.

I usually rely on words more than pictures in my NC writings. Here, a picture really is worth a thousand words.

Source: Imogen E. Napper and Richard C. Thompson, “Environmental Deterioration of Biodegradable, Oxo-biodegradable, Compostable, and Conventional Plastic Carrier Bags in the Sea, Soil, and Open-Air Over a 3-Year Period,” Environmental Science & Technology; link here.

The bag looks disgusting, but it is more or less intact.

What Does This Mean?

It means there’s no technofix alternative if we wish to reduce or eliminate plastic waste in the marine environment to stopping most use of plastic now. Period.

Just as the recycling fairy won’t rescue us – a notion I have previously debunked at length here. Many were shocked to find  the recycling they carefully sorted was not in fact, being recycled close to home – if it was being recycled anywhere. Instead, it was shipped to China and other destinations – where it was, shall we say, imperfectly processed. China then decided to forgo being the destination of choice for such waste and in 2017, stopped accepting most plastics imports for recycling.

What happened next? The US and other places shifted to shipping their plastic waste to Southeast Asia, as I discussed here. Many US cities and states eliminated or curtailed their recycling programs .And more recently, other countries have followed China’s lead, including last month, India, as I discussed here, and stopped accepting plastic waste imports, thus exacerbating the global recycling crisis further.

Well, guess what folks: neither is the technofix fairy riding to the rescue anytime soon. This latest paper “examined biodegradable, oxo-biodegradable, compostable, and high-density polyethylene (i.e., a conventional plastic carrier bag) materials over a 3 year period.” To be sure, the study did reveal some differences in the relative rates of disintegration, depending on whether different bags were buried, dumped in the sea, or simply exposed to air.

But the money quote (from the abstract):

Collectively, our results showed that none of the bags could be relied upon to show any substantial deterioration over a 3 year period in all of the environments. It is therefore not clear that the oxo-biodegradable or biodegradable formulations provide sufficiently advanced rates of deterioration to be advantageous in the context of reducing marine litter, compared to conventional bags.

The Guardian quotes Imogen Napper, leader of the study:

 “After three years, I was really amazed that any of the bags could still hold a load of shopping. For biodegradable bags to be able to do that was the most surprising. When you see something labelled in that way, I think you automatically assume it will degrade more quickly than conventional bags. But, after three years at least, our research shows that might not be the case.”

I should mention that this account from Dazeen talks to makers of some bioplastics, who claim that their products do work if recycled at the proper facilities.

And Vice reports on this issue further:

According to Brandon Gilroyed, an associate professor at the University of Guelph’s School of Environmental Sciences, the bar for being able to use these designations is pretty low. A product can be marketed as “biodegradable” as long as it breaks down over some unspecified period of time. “Compostable” means that under perfectly engineered industrial composting conditions, where products are subjected to several days of high heat, materials will break down.

“There’s a disconnect between the definition that manufacturers have to meet to [label] that product, how it’s marketed, and what the consumer expects from that product based on how those terms are used in pop culture,” he told VICE.

Gilroyed says there’s a level of public education that’s missing; most consumers don’t know that these products break down under very narrow circumstances.

He says the danger is that these labels can encourage people to be complacent, while making them feel like they’re doing something good for the environment. “People think it’s OK just to throw it away, because it’s biodegradable, and they don’t feel bad about it.”

Yet consumers think they’re doing the right thing by opting for such bags instead of the ordinary alternative. Most of them aren’t going to peruse this study to determine exactly what type of bag they have, and how to dispose of it optimally. So I ask then: why place such faith in the use of such materials as solutions to the single-use plastic bag problem?

UK Consumers Say They Disdain Plastic Packaging

As I’ve discussed here, 62% of UK consumers say they’re concerned about reducing plastic packaging and increasing use of recyclable materials. Over to The Guardian again:

About half of plastics are discarded after a single use and considerable quantities end up as litter.

Despite the introduction of charges for plastic bags in the UK, supermarkets are still producing billions each year. A survey of the top 10 supermarkets by Greenpeace revealed they were producing 1.1bn single-use plastic bags, 1.2bn plastic produce bags for fruit and vegetables and 958m reusable “bags for life” a year.

The Plymouth study says that in 2010 it was estimated that 98.6bn plastic carrier bags were placed on the EU market and about 100bn additional plastic bags have been placed every year since.

Look, I’m a consumer too, and I do my own food shopping. I go to the farmer’s market or the food store, rather than pop on-line and have my order delivered. I like to pick out my own produce, fish, and meat. So I know how hard it is to avoid plastic packaging – especially in so-called developed countries, no matter how hard I try.  When I’m on the road in places such as Turkey, India, Thailand, or Indonesia, it is far, far easier to buy just what I need – and insist that it’s not swathed in plastic, and merely placed in my well-used cotton carrier bags.

That aside, it only takes a bit of planning not to take single use carrier bags in the UK or the US. This is actually rather low-hanging fruit.

Now that you know the ‘environmentally-friendly’ ones aren’t, exactly, enivornmentally-friendly? What can you do? The best answer I can come up with is to use fabric, string, or paper bags.

For readers new to this topic, I also include a short round-up of steps individuals can take to reduce their use of a wider range of single-use plastic here.

I harbor no illusions these steps alone or collectively each of us might take to reduce use of these environmental poisons will amount to more than some small dribbles into a very large bucket. What we need is sustained coordinated global regulation, and as I’ve previously discussed here and written here and here, even the EU – which purports to be a leader on this issue – has instead produced policies that don’t begin to grapple with the scope of the problem.

The Long View

Now, in the longer run, scientists may indeed develop environmentally-friendly plastics. I really hope and wish they succeed.

But this study suggests: we’re not there yet. Even in this one small area, where countries have banned the bags, or imposed a charge on their use. So there should have been plenty of incentives to develop compostable or biodegradable bags that actually performed as claimed.

And a hint to the cynical: even if they tell us some golly gee whizbang innovation is going to solve the plastic problem – without forcing the plastic pushers to stop producing plastics from fracked fuels – and instituting draconian bans on use of these poisons, guess what? I won’t believe them.

Let me highlight another quote from The Guardian account, one to remember when told the technofix fairy offers a solution to a problem that otherwise would require major changes – especially when huge profits are at stake.

According to the Guardian, Prof Richard Thompson, head of the unit that conducted the biodegradable bags study “said the research raised questions about whether the public was being misled.”

We demonstrate here that the materials tested did not present any consistent, reliable and relevant advantage in the context of marine litter,” he said. “It concerns me that these novel materials also present challenges in recycling. Our study emphasises the need for standards relating to degradable materials, clearly outlining the appropriate disposal pathway and rates of degradation that can be expected.”

They have another deficiency, as reported by Dezeen:

Architect and recycling expert Arthur Huang recently warned that bioplastics could be worse for the environment than standard plastics made using fossil fuels.

“If we use them the same way [as conventional plastics] they are just as bad if not worse,” he told Dezeen earlier this month. “They change the pH value of soil and water as they degrade, and they take away valuable food supplies.”

Great! So they don’t degrade, they also muck up the already-stressed recycling system, and they may also alter the pH of soil and water as well reduce food supplies. Any other good news to report?

The Last Word: The Scientists

After I wrote this post, I found this video, featuring Thompson and Napper. I want to allow them the last word.

There’s no transcript, but it’s only three minutes.  It’s a great encouragement to critical thinking – which NC strives to promote. The worldview of the younger scientist, Napper, clearly changed as a result of this study – she now realises you can’t accept the claims of makers of such products. I hope she develops that insight during a long, interesting scientific career.

Print Friendly, PDF & Email


  1. PlutoniumKun

    When I was doing some research into this in the late 1990’s, ‘biodegradable plastics’ meant, when you looked more closely at the small print, ‘it will degrade in UV’. This has some use for plastics being blown around in the countryside or caught up in bushes, but little else. They certainly don’t degrade in deep water, mud, or within landfills.

    In fact, plastics actually prevents the natural degradation of other products within landfills by interfering with water flows – this is a significant problem for landfills with landfill gas traps and associated power plants – the more plastic, the less consistent the production of methane. Most likely because it creates pockets of suspended water, instead of the ‘ideal’, which is slowly moving water to promote anaerobic breakdown and so steady methane production and gradual biological stabilisation of the fill. Some landfills refuse to accept non-shredded rigid plastics for just this reason.

    1. rd

      My experience with photo-degradable plastics is that even a slight amount of shading (say on the ground surface in grass) means it doesn’t photo-degrade over several years. If it gets some soil on it, it will take decades or centuries to degrade.

      So photo-degradable works great pinned down to a surface in the Arizona desert with lots of sun and no vegetation. Mainly useless elsewhere.

    2. Cal2

      25 years or so ago, we did a similar study on the “Will degrade in UV” plastic wrap that magazines were mailed in. Plastic bags for paper magazines? So that they could contain loose subscription cards, loose advertising and most importantly, perfume samples. (Previously mailmen had gotten sick from a racks full of commercial mail in trucks on hot days.)

      Simple test, staple the bags to a plywood sheet in full western sunlight and wind in San Francisco.

      They “degraded” into little strips and fragments that blew into the bay, leaving bits under the rusting staples. Elimination of plastic is the solution.

      Magazine subscription cards with pre-paid postage were and still are excellent vehicles for sending a message to the publisher and the advertisers.
      “We will not buy your magazine embalmed in plastic”
      “Buy your product advertised in plastic wrapped magazines”
      “Buy your magazine as long as you advertise lung cancer death”
      “Buy your product advertised next to lung cancer death”.

  2. vlade


    My experience with the UK Tesco bags (the cheap ones) was that after a few months (arguably, not burried anywhere, just exposed to air) they turned into sort of a white snow. Not that I’d say it was any better per se (smaller parts of the same plastic are no better than one large, I have no idea what was happening chemically to them), but you’d never be able to carry anything in them.

    1. Doggrotter

      Yes, I found my cheap storage system in the attic had turned to powder when I returned.

      1. Jerri-Lynn Scofield Post author

        No doubt that “powder” either is or contains microplastics – which have been turning up everywhere.

      2. Steve H.

        As a toxicologist I have a reflexive reaction against Carbon-Chlorine bonds. A nasty tendency for complex stable endocrine disruptors. I wouldn’t consider that white snow to be inert.

        A partial answer: cellophane. 100% biodegradable at the point-of-use.

        1. Cal2

          I suppose next a luddite like you will claim that
          drinking straws can be made of paper, along with their sanitary wrapper? /sarc

          Would like to add that AARP, “American Association of Retired Persons”, is sending out two plastic credit card sized non-recyclable “Membership” plus “Benefit” cards, per mailer, to every older person that I know, every six months, trying to hustle suckers into joining their insurance corporation masquerading as a non-profit.

          See what happens to environmental baddies? They get shamed. Don’t forget online review sites for restaurants and other businesses. These can serve as three-way advertising. Advertiser to you, ” ” “others, you to advertiser and others.

  3. Krystyn Walentka

    First, as I read this article I noticed an advert for the “Purple Mattress” in the side bar, which is made from 2” hyper-elastic polymer material. Yikes.

    Second. My local “coop” (they are not really a true coop) decided to do away with plastic AND paper bags and offer a choice of bags in case you need one. I was proud of them, but, from their website:

    You can choose a “Weaver Bag” for 99 cents or an insulated bag for $1.99, or to use a “Bring it Back Sack” made of heavy-duty recycled plastic sturdy enough to be re-used up to 125 times. New sacks can be purchased for 15 cents, or customers can pick up a free sack from a stash of returned bags.

    So, still plastic, maybe less, but still plastic. I hoped they would just go to paper bags and charge for the paper bags. Or no bags at all. I feel they are taking the easy corporate way out with their choice. I have a cotton bag I have used forever and if I forget it I just buy what I can carry or fit in my backpack.

  4. philnc

    More evidence of how we’ve all been thoroughly propagandized for generations. Many of us thought we were so smart and sophisticated to know all about the wonders of diesel, ethanol, fission, “clean coal” and biodegradable packaging. We were scammed, and the scammers laughed all the way to the bank. As Greta Thunberg has said, this isn’t a case of us all being responsible though. There are specific people and companies who drove us into this ditch, “and made unimaginable amounts of money” doing it. We really can’t trust official or semi-official sources of news or product information, and sadly never could. The corruption that caused this is deep and broad, and will have to be dealt with.

    Around 10 years ago when we replaced all the incandescents with CFLs, I was amazed to see how much power we saved and how long they lasted. But there was a lie wrapped into that story: CFLs were toxic time bombs that over time will harm the environment and our health. The half measure of recycling later turned out to also be mostly a fraud. Played once again. Future generations lost again, but who won? That question needs to be asked.

    Back almost 40 years ago when I was in law school we used to go to this discount supermarket where you had to bring your own bags or boxes, preferably cardboard (we were the newly emancipated kids of working class families without trust funds to cover the rent, let alone pay for food delivery — we did pick up at Dominos). Very few products sold there had plastic packaging. Mostly white cardboard with plain, black letter, labels like “Corn Flakes”. Although we didn’t appreciate it at the time, that market was probably the most environmentally friendly business we patronized.

    1. Monty

      À la Lanterne!

      I wonder what other dangerous lies we are still being told/sold?

  5. Joe Well

    What percentage of the plastic in the ocean is discarded fishing gear? I think worrying about the plastic wrapping of fish is a misplaced concern when fishing is one of the biggest problems facing the seas.

  6. TG

    It doesn’t matter how many people we jam into the Earth, technological fixes will ensure a bigger pie for all.

    It’s easy to reduce per-capita waste. So if we double the population, we just have to reduce per capita waste by 75%, and that’s easy! The notion that, for an industrial society, reduction in per-capita environmental impacts are possible but will generally be difficult and slow, and easily cancelled out by jamming in more people – this is clearly racist and fascist.

    So whatever we do, we must not allow ourselves to be seduced by the toxic notion that massive increases in population make saving the environment harder/impossible.

    The population of the United States, which has been boosted by about 100 million since 1970 by government policy, must be increased to half a billion by 2050, and ideally to a billion and beyond within the span of those now living. The population of Canada must be increased to 100 million. Africa must increase its population to 4 billion by the end of the century. Japan, which looks to have a moderate population decline to maybe 60 million or so, simply cannot be allowed to do that: no, they MUST have more workers and MUST boost their population to at least 2 or 3 hundred million. Never mind what the people themselves say, the experts know better how many children we should have.

    Because more people are always better regardless of circumstance, and cutting per-capita waste and pollution is simple cheap and easy and the only reason we are not doing it is because Trump is evil.

    1. Curtis

      Way back in the day the concept was “overpopulation”. We now know that Midas was an organic polymer chemist and that the beginning of this situation was “the best thing since sliced bread “ ie now we have to keep it from drying out, hence plastic packaging.

  7. Michael

    We are using kitchen trash bags made with 55% recycled / 16% post recycled plastic. Label says a layer of recycled material between two layers of virgin plastic, “Now stronger”. Further investigation showed recycled plastic not strong enough on its own. Progress?

    It just dawned on me that we are putting plastic packaging (can’t avoid it all) into plastic trash bags, which sits in my plastic garbage can for the week until I put it into my plastic garbage “can / toter” on the street to be picked up. (head slap)

    We are truly insane at this point in our evolution.

    1. jrs

      You could try paper bags, the kind they give out at the grocery store (or charge you for at the grocery store these days), double bagging the trash in two of them if it’s very wet. I admit it’s a bit less convenient if there’s lots of people and lot’s of trash, but it works.

  8. Off The Street

    On a related plastics note, here is a link about Bisphenol-A information on PBS. That chemical is in almost all of the plastic bottles that you see, and it has some nasty endocrine disruptor properties in addition to being an overall pollution problem. If it doesn’t get you and yours through genetic destruction it will through seafood.

    One PBS documentary included a world map with the gyres in the east and west Pacific, and their analog garbage patches in the Atlantic and Indian Oceans. A shocking segment showed the presence of so many plastic bits in now-murky seawater even in the remotest parts of the oceans. Those appeared to be from bottles that had degraded through UV, pounding against rocks or whatever method of destruction, but didn’t capture the visual impact of little micro-beads that are also ubiquitous.

  9. Samfan

    As an owner and occasional slave of a mid sized dog (a lovely, snow white samoyed), I could not survive without plastic bags to pick up after him. After reading through too many online reviews we decided to stop using the store plastic bags for this task and use a well known doggie bag that claims to be biodegradable. If this is all a lie, what’s the recommended solution?

      1. Samfan

        LOL, but I’m thinking I’d rather have you tell my wife that she needs to carry these items when walking the dog. :-)

  10. lordkoos

    Single-use plastic should be completely banned. I’m floored by the sheer amount of plastic packaging, and instead of reducing it, companies seem to be doubling down and using even more plastic, in ever more creative ways. For example, some upscale brands of tea now come in individual paper envelopes to keep the teabags fresh, but the paper is laminated with a thin shiny layer of plastic, so they can’t be composted or recycled with paper products. Milk and juice cartons now all have little plastic inserts as pour spouts (what was wrong with the old folding cartons, which were waxed cardboard?), and I see most of the junk mail brochures and flyers we get now also have a plastic laminate on them to give a glossy surface. Then there is the ridiculously oversized plastic packaging on a myriad of consumer goods which often require opening with a knife or strong pair of scissors, while plastic packing materials such as bubble wrap are ubiquitous as well. We really should be shopping the way people did long ago — bring your own glass, metal or cardboard containers and buy products out of a bin in bulk form.

  11. Darius

    PLA is generally considered completely biodegradable, eventually. It’s good for disposable cups and, I think, cutlery. There are no drop in replacements for a lot of single use plastics. Back to glass, metal cans, and wood.

  12. ewmayer

    Just thinking of my recent grocery-shopping trip:

    o Fruit I put in a plastic handle bag of the kind of re-use many times until it starts to fall apart, at which point it goes into recycling, but let’s assume it ends up as trash. I much prefer this system to reusable cloth bags because I am constrained in how much stuff I can cram into my messenger-bag-carryall, and a flat-folded plastic bag takes almost no room. So using that a couple dozen times at least cuts plastic usage drastically versus single-use-then-discard.

    o Roast chicken I took home in a plastic clamshell container — I washed said container with soapy water afterward and placed in recycling. if it actually gets recycled great, but if not – what is a good alternative packaging here? And please no “roast your own chicken” non-replies – that’s a multi-hour fuss-and-mess deal to do at home, and I’m pretty sure it’s actually far better in terms of total carbon footprint to let the Whole Foods folks do it in their dedicated large-scale rotisserie oven, economy-of-scale-style. So, what is a good alternative packaging for a hot roast chicken, that avoids leaks?

    Pessimistically, given the now-clear extent to which recycling programs in the US have been an out-and-out scam, I’m thinking it might be best to just stop wasting people’s time sorting ‘recyclables’ which will get shipped to some shi*thole country and/or landfilled anyway, and start focusing on deployment of high-temp “clean” incinerators, the kind which can break down even the toughest organic-chemical compounds. Separate the glass and metal and nasty toxics-containing stuff like electronics/batteries, burn the rest. At the same time really crack down on single-use plastics to reduce their presence in the waste stream. But I’m sure human corruption, selfishness and greed will get in the way of *any* common-sense approach in this country.

    1. eg

      The “organic” roasted chicken at our local supermarket (Fortino’s) is packaged in paper bags with some kind of waxy inside coating; there’s also some cellophane-looking window in the paper bag

      So, probably still environmentally bad, but probably better than the plastic clamshells that the “not organic” roasted chickens come in?

    2. SRH

      Single-use plastics are used all over the place. What is the alternative to plastics in screens and cases for our many devices, from phones to TVs?

  13. Greg

    Paper bags are not great replacements, very intense chemical processes involved in making them and they’re terrible for reuse in most cases.
    Biodegradable and compostable are as has been mentioned mired in fine print that make them pointless in most cases.
    Recyclable has turned out to be just a different way of saying landfill in a different geography, in most cases.

    When we worked through the options at my large socially-aspirational organisation, the most environmental impact we could achieve was to reduce the oil content in the plastics we were using. Thinner films with slightly more complex manufacturing to achieve the same technical spec and strength. No way to explain that on marketing though, consumers believe brown paper is best regardless of the realities.

  14. SRH

    I find the debate over plastics to be shallow and without viable solutions, no matter who is discussing it. Why focus on packaging? Plastics are used almost everywhere. There is as yet no realistic alternative to its use in electronics, construction, clothing (is wool or cotton superior? In many ways not), vehicles and so on. Yet we are aiming to completely end the use of fossil fuels, which is a contradiction.

    I’m looking at this from the perspective of a green socialist who sees our capitalist system as largely responsible for climate catastrophe. We seem to have painted ourselves into a corner and technology will not provide much of a way out.

Comments are closed.