The world hates plastics right now (for good reason). The material has become a grim emblem for the all-pervasive threat posed to our planet by human waste – a threat that has dispersed itself to the deepest depths of the Mariana Trench and that lives in the very guts of the creatures whose habitats these materials are ruining. In many senses, this pariah status is well-earned. The images in our media of bottle-strewn beaches and strangled seals are heart wrenching. However, while it may sound sacrilegious in the current atmosphere, not all plastics are bad. Many perform functions that are vital to ensuring Earth remains a viable home both for humans and wider flora and fauna. Our ambition is to cut down the use of single plastic and help reduce plastic consumption. But below is a technical explanation of the types of plastic - the good and the ugly.
The first thing to understand is that not all plastics are the same. There are an array of different types, which traditionally have fallen into two categories: thermoplastics, which you can melt down over and over to your heart’s content, and thermoset plastics, which you can melt only once. The basic reusability of the former makes them far superior when it comes to sustainability and there is so much thermoplastic material in circulation already, that it makes most sense to focus on salvaging and recycling these, rather than adding new polymers to the system.
There is a third subset where different types of plastic are Frankensteined together to create composites – and in sustainability and quality terms, these are the worst of the lot. Generally, plastics have similar melting points, so when you mix them all up it makes them a nightmare to separate and thus recycle. But if these and the images of choking wildlife represent the ugliest side of plastics, you don’t have to look far to find examples of how they continue to benefit us.
As we approach a number of important tipping points for the world – not just in terms of observable shifts in the planet’s condition, but also in public awareness of the environmental problems – once again we are confronted with the challenge of nuance. It’s not just a question of the material itself being simply “bad” or “good”, it is about how we as a species choose to use that material.
While often thought of as a modern evil, humans have been incorporating types of plastic into our daily lives since approximately 1600 BC, when the Mesoamericans first processed natural rubber into balls and figurines.
From medicine to fresh water and the internet
Today, plastics are hugely important to modern healthcare and medicine, used to make blister packs, disposable syringes, blood bags, pill sheaths and heart valves; the outer shells of MRI machines, in the cables and wires that keep life-preserving hospital machinery up and running. Without them, there would be no internet, no space travel, no fresh water piped into our towns, cities, remote villages and refugee camps. Clearly, these are positive uses of plastics, which take advantage of the fact they are lightweight and durable. Conversely, these qualities are what help 8 million tons of plastic find its way into our oceans each year – so maybe we arrive at the conclusion that we could do without the crazy amount of gift shop tat that we consume while on holiday, or the need for a new plastic bottle every time we are a little thirsty.
For now, the best type of use is re-use. The only plus side of the alarming amount of plastic waste we have generated is that it has given us literal landfills full of readymade material to bend to our will, so let’s exploit these vast and expensively accumulated reserves of trash. Plastics are also better for the planet than other, more natural materials that are thought of as being somehow more benevolent and trustworthy – for instance, they have a lower melting point than metals, which makes them loads more energy-efficient to recycle. They emit fewer carcinogens than MDF. Polyester gets a bad rap but the cotton industry is arguably one of the most heinous there has ever been, leaking toxic dyes into rivers, using up vast swathes of water and land that could otherwise sate thirst and grow crops, inextricably bound to its history of encouraging slave labour.