This month we are upping the bar with an article that’s well written and wildly informative. Yes we have a guest post……
While trawling through the internet I stumbled across the fantastic website www.explainthatstuff.com written by Chris Woodford. It is all more than good but there was an article on plastic so pleasing that I had to ask if I could reproduce it. Didn’t I just fall off my chair with excitement when he offered to write something for the blog? So I thought I would ask all the questions that troubled me about plastic and see what he thought.
But before we begin… let me introduce the man:
Chris Woodford is a British science writer. He has an MA in Natural Sciences from Cambridge University and specialized in physics (he studied at the Cavendish Laboratory) and experimental psychology. Other skills include chemistry, crystallography, materials science, and math. He had his first magazine article published in 1980 and he went on to write, amongst others, the( best-selling), how-it-works books
What is plastic anyway?
Is there anything remotely good about plastics?
Absolutely! The clue’s in the name, really. Plastic means “nasty stuff you can’t get rid of”, but it also means flexible–and that’s the good thing about plastics. They can do all kinds of useful things for us. From the moment you’re jolted awake by a plastic alarm clock, to the moment you brush your teeth with a nylon toothbrush and get back in bed again, plastic fills your every waking moment. I’m wearing a polyester fleece right now made from old plastic bottles, typing on a plastic computer keyboard, listening to music through plastic headphones and thinking occasionally about the dirty breakfast dishes sitting in the plastic washing-up bowl.
So what’s the downside?
Everything that’s good about plastic has a downside. There are dozens of different kinds of plastics, which is great if you’re a product manufacturer and you need to find something that does a very specific job. You use quite different plastics to make water bottles and milk bottles, for example, and plastic bags are made from something different again. That’s not so good if you’re a local council with the job of collecting plastics and trying to recycle them, because they pretty much all have to be recycled in different ways. Plastics are very cheap, which means we can use them for virtually anything. But the drawback there is that we now rely far too much on disposable things that benefit no-one except the people who make and sell them. And because plastics are essentially synthetic chemicals–ones we’ve dreamed up in laboratories–there aren’t really natural mechanisms that break them down. Animals and insects don’t eat plastics. Those long chains of molecules just sit there. And they go on sitting there–potentially for hundreds of years.
Hundreds of years?!
Hundreds of years! A plastic bottle can take 500 years to break down. That’s not a timescale we can readily appreciate. A human might live 80 years, so a plastic bottle lives six times longer. Or we could think of it in a completely different way. Imagine you come across an old plastic bottle someone’s thrown into your front garden. Now if plastic lasts 500 years, that bottle could have been thrown there by King Henry VIII
Image via Wikipedia
on his way back from the pub! It could be older than everything in your street–all the trees, the houses, the cars, the people… everything. Now of course that’s not actually true because plastics weren’t invented in 1511. But roll the clock forward five hundred years from now, to 2511, and it’s quite possible that the person living in what’s now your house will dig up the garden and find bits of plastic you left behind. Or that a 25th-century Tony Robinson will make archaeology programmes on TV about sifting through all the random bits of plastic in a 21st-century landfill.
But we’re recycling so much more plastic now?
Or are we? Over 90 percent of the plastic stuff we buy still ends up in a landfill. That’s bad for all kinds of reasons. Landfill is just a more polite word for litter; it’s litter on a grand scale! Not only that, it’s such a waste. Most plastic comes from petroleum–and we know oil is going to run out sooner or later. Apparently, something like 200,000 barrels of oil a day are used to make plastic for packaging, just in the USA–a huge waste, and most of it going to landfill in a matter of days or weeks. There’s also the question of energy. It takes far more energy to make disposable plastic things than it does to use the same things over and over again. Recycled plastic is much better than brand new plastic: it saves about two thirds of the energy used in manufacturing. But, quite frankly, recycling is only a little bit better than throwing things away. It’s far better not to use plastic at all than to recycle it. It’s much better, for example, to have a reuseable aluminium water bottle that you fill up from the tap each day than to buy plastic bottles of water and then very conscientiously recycle them. Where do they go after you’ve recycled them? It takes a lot of energy to transport them, melt them down, and turn them into new plastic products that may (or may not) be recycled. Far better to eliminate the plastic completely if you can.
Do plastics have to be so bad for the environment?
Absolutely not. The thing to remember about plastics is that humans created them. Chemists in laboratories engineered pretty much all these polymers and designed them to do very specific jobs. There’s nothing random or accidental about it, so why should there be anything random or accidental about how we dispose of them? In other words, there’s no reason why chemists can’t engineer plastics that can be disposed of more easily. In fact, they’re already doing just that. We’ve had biodegradable plastics for several decades and now the industry buzzword is “bioplastics”: plastics made from more natural ingredients that break down much faster when we dispose of them.
That sounds brilliant! How do they work?
A really good example is the kind of packaging you now find on many sandwich containers. Go back ten or twenty years and take-away sandwiches always came in plastic triangles that you simply threw away. Who knows what happened to them? Well most of them–hundreds of millions of them–are sitting in landfills under our feet. What a waste! And what a disgrace! Buy yourself some sandwiches today and it’s a very different story. You’re probably going to get a cardboard container (which is easy to compost or recycle) with a thin window made of what looks like ordinary, thin plastic. But it’s more likely to be a bioplastic based on corn starch (the stuff you put in sauces to thicken them up). The bioplastic has these little chunks of cornstarch embedded in it. As it picks up moisture, the starch swells up (just like your sauce thickens) and cracks the plastic into tiny fragments that break down more quickly–typically in just a few months. Things like greetings cards are now being packed in the same stuff. Other bioplastics (ones that don’t use cornstarch) are designed to be broken down by sunlight, water, or high temperatures.
Does bioplastics have any drawbacks?
It would be great if all the plastic we couldn’t avoid using was either reused in some way or recycled. Realistically, though, that’s never going to happen: most bioplastic is going to end up in a landfill, just like ordinary plastic. So we still need to think about that very carefully. Some bioplastics disappear very cleanly in landfills. Because they’re made from plants, they absorbed carbon dioxide when they grew in the first place and they release that carbon dioxide again when they break down–so effectively, ignoring the energy used in manufacturing, they’re carbon neutral: they don’t add to global warming. Other bioplastics break down and release methane, which is a really powerful greenhouse gas (much worse than carbon dioxide). That’s a serious issue. Some also leave a toxic residue in the landfill, which could cause water pollution or soil contamination. Another problem is that bioplastics can’t be recycled the same way as ordinary plastics so if they all get mixed in together in a recycling container, you can end up with a huge pile of unprocessable waste that has to go to a landfill. There are other issues too. Some bioplastics are described as “compostable”, but they only compost in the kind of high-temperature digesters operated by councils, not on your average, low-temperature, home compost heap.
So not really a complete solution?
Definitely not. You have to go back to what we were saying right at the beginning–about how many different kinds of plastic we use and in how many different ways. You can’t really make a plastic washing up bowl from bioplastic–it would slowly disintegrate before your eyes! But what else are you going to make it out of? And if you accept that it’s not something you’re going to keep forever, what happens to it when you throw it away? Ditto with a toothbrush: it’s something you have to throw away and replace (if you want to keep your teeth).
What’s the answer to that?
The way to look at these things is always reduce, reuse, recycle–in that order. So you first have to ask do I really need a plastic washing-up bowl? Can I wash up in the sink, which is what people always used to do until about the 1960s and 1970s. If I have to throw it out, can I do anything useful with it? Can I use it in the garden to collect weeds, perhaps? Can I clean it up and use it for storage? If I really have to get rid of it, can I possibly recycle it?
But for disposable packaging…?
Well, there bioplastics definitely have a big part to play. If you bear in mind that plastic bags have an average useful life of 12 minutes, but live on in landfills for 500 years, you can see there’s a real value in having plastic food packaging that disappears very quickly. Especially for things like sweets and crisps, where there’s a high chance that any packaging is going to end up as litter. But bioplastics aren’t the only solution–and they may not even be the best one. Another option is to turn the problem back on the manufacturers. The main reason we have plastic packaging is to extend the shelf life of foods so that big corporations can make more money. Okay, fine, so let them accept some of the responsibility for the “plastic monster” they’ve created. Eco groups like Surfers Against Sewage have been campaigning on this for some time, encouraging people to post rubbish they find on beaches (80% of it is plastic, incidentally) back to the companies who produced it. (They call it “Return to Offender”!) Packaging is relatively easy to trace back to the people who made it–it’s stamped with their name. So how about councils being able to fine manufacturers for litter as well as the people who drop it? We’re hearing now that the cost of litter collection in the UK is soon going to hit a billion pounds a year. Let the people who profit from packaging pay some of the costs. Then they’d put a bit more effort into educating people about disposing of waste, using less packaging, and developing more eco-friendly plastics.
What’s the one thing people should take away from all this?
King Henry VIII! Remember how long plastic lasts and what it costs the environment (in resources, energy, and litter). Use as little of it as you can. When you get rid of plastic things, try to give them another life first (use your old toothbrush for cleaning your bike, or whatever) and recycle them if you can’t. There’s no excuse for plastic litter–and throwing away plastic is almost as bad
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