Plastic isn’t just a pollution and public health problem; it’s the fastest growing industrial source of greenhouse gas emissions on the planet!

Yikes. It’s true: the production, use and disposal of plastics are now estimated to contribute up to 8% of global greenhouse gas emissions each year, compared with the whole aviation industry (estimated at around 3.5% of emissions). This doesn’t mean it’s okay to take the plane when there’s an alternative option! It’s just to give you an idea of the scale of the problem.

But how is that amount of emissions even possible? By now, we know plastic is made of fossil fuels + chemicals. In the 1950s, when it first came into wider use, plastic accounted for less than 1% of global oil consumption. These days it uses around 7% and this is projected to increase to 20% by 2050. This is because big oil companies believe making more plastic will save their profits as the world moves away from fossil fuels to towards renewable sources of energy.

To understand the climate impacts of plastic though, we don’t just look at its ingredients. We need to consider its whole journey, from how it’s made to what happens after it’s thrown away – a.k.a. its lifecycle. This gives us a much fuller picture.

Let’s break down the hidden emissions during the lifecycle of plastic.

EMISSIONS FROM EXTRACTION & PRODUCTION

Plastic’s journey begins with the extraction of fossil fuels from the Earth, which emits greenhouse gases like carbon dioxide and methane. The refining and manufacturing processes (the cracking and polymerisation we learned about in Part 1) then release more CO2 and other pollutants into the atmosphere. Around 90% of the greenhouse gas emissions associated with plastic are created at this production stage.

Plastic is also transported at every stage of its life and this uses more fossil fuels.

EMISSIONS FROM DISPOSAL

The endless stream of plastic packages and products we deal with every day will usually end up either in a landfill or incinerated. A small amount gets recycled. And a lot of plastic also gets into the environment – there’s more about that below.

Landfilling plastic, especially when mixed up with food waste and other organic material, creates conditions where methane is produced. Methane – which you may know from cow farts – is a greenhouse gas that’s way better than CO2 at trapping heat in the atmosphere. It makes climate change happen at a much faster rate.

Landfills are the world’s third largest source of methane emissions (cows and other agriculture come in – appropriately – at no. 2, with energy production taking the top spot). Making sure food waste doesn’t end up with plastic and other non-organic material in the landfill would reduce this a lot.

Incinerating plastic is a big problem. As it’s made from fossil fuels, it has the same climate impacts as burning oil and gas, with added toxic chemicals being released – often near where people live.

A small amount of plastic gets recycled and this process generates some greenhouse gas emissions, but far less than when new plastic is produced. In theory, that makes recycling more plastic a good option to slow climate change. But there are other issues with plastic recycling, which we’ll see later, that mean it’s not as helpful as we might think.

EMISSIONS FROM PLASTIC IN THE ENVIRONMENT

Scientists have found that plastic in the environment reacts with sunlight to release methane and other greenhouse gases. Microplastics are also a climate problem in the atmosphere and in the ocean. In the atmosphere, microplastics can trap heat, just like other types of air pollution.

In the ocean, there’s a different effect. Marine ecosystems help to absorb and store around half of the carbon dioxide on our planet, making them the world’s biggest “carbon sink”.

A lot of this CO2 is captured by plankton and other microorganisms in the water and then transported to the deep ocean in their poo. But the increase of microplastics in their diet is interfering with this process. As the water becomes more contaminated, less carbon dioxide can be absorbed. This threatens not only the climate, but the balance and even the survival of these beautiful and important ecosystems.

In summary, we might say that plastic has important and often unexpected negative effects on the climate at every stage of its life. The largest part of its impact comes when new plastic is produced, but it continues to create emissions after it is thrown away. It can even interfere with the planet’s natural processes to capture CO2 in the ocean.

To find out more about plastic’s impacts on climate change, check out our reading and watch lists below. Take your time to explore whatever appeals to you. You can also apply your new knowledge in an activity, or test it out in the quiz. If you have any thoughts on plastic and our climate, or want to answer the question below, leave us a comment!

If you’ve checked out the previous two parts of this series, you’ll already have heard of microplastics.
Microplastics – and their even tinier cousins, nanoplastics – may be small but they are a really big deal!

In this episode we’ll be finding out why, where they come from, and how they even get into our bodies in the first place.

Scientists usually define microplastics as any piece of plastic under 5mm (or half a centimetre) in length. Some of them are visible but most are too tiny to be seen, going down to just 1 micron (or one thousandth of a millimetre) across. When they get under this size, they are usually called nanoplastics. But to keep things simple, for now we’ll just call them all “microplastics”.

WHERE DO MICROPLASTICS COME FROM?

Most microplastics start life as part of something bigger. As these items get produced, used and thrown away, microplastics are released. This usually happens in 3 ways:

Friction: two of the biggest sources of microplastics are textiles and car tyres. Making, washing and wearing clothes made from synthetic fibres like polyester or acrylic releases tiny microfibres. So too does making, walking or sitting on synthetic carpets and furniture. And when people drive, the friction between their tyres and the road surface creates tiny particles of microplastic dust (if you thought tyres were only made from rubber, think again – they are about 1/4 plastic). In a 2020 study, 78% of microplastics in the ocean were found to come from tyres!

When any plastic gets hot and comes into contact with other things, the surface breaks down much more easily, for example when cooking with plastic utensils, microwaving a ready meal, or putting your fleece in the dryer.

Fragmentation: when plastic gets old, or is exposed to things like sunlight or wave action, it can get brittle and start to break up into smaller and smaller pieces. This happens very often in the ocean or in open dumpsites, but also on farmland, where plastic is used to cover crops.

Incineration: Burning plastic along with other waste is a common way of managing the trash we produce. This creates a lot of microplastics both in the emissions and in the ash left behind.

Other microplastics, like glitter, start off small – and get smaller over time. Liquid plastics are common ingredients in toiletries like lotions, makeup, hair conditioners and toothpaste, where they are used to bulk out the product and to make your hair and body smooth and shiny. These all wash into the water system as microplastics after use.

Nurdles are small pellets of plastic used to make plastic products. Millions of tons are made every year and transported all over the globe, but accidental spills or careless handling mean many of them end up in the environment, where they can break down even further.

HOW DO MICROPLASTICS GET INTO OUR BODIES?

Some very small microplastics, like tyre dust or textile fibres, can float unnoticed in the air. While some will eventually settle, there’s so much new material arriving and being blown around, the whole atmosphere is full of it – both indoors and outdoors. You’re definitely breathing in plastic right now.

Any size of microplastic can enter the soil and water, either directly or through the sewage system. This means both plants and animals are exposed to microplastics and, as we eat plants and animals, the microplastic ends up in our bodies too. Because microplastics are so widespread and so tiny, this is not something we can see or control.

Then of course we’re also spreading microplastics on our skin, hair and nails and consuming more of them directly when we buy, cook and eat food and drinks wrapped in plastic.

WHAT ARE THE EFFECTS OF HAVING MICROPLASTICS IN YOUR BODY?

Scientists are still studying all the effects microplastics might have on our health. The main issue is with all the chemical additives used to make plastic. These additives can make up more than half of a plastic material!

A lot of research has shown that these chemicals can be toxic and also affect the way our hormones work. This can lead to an increased risk of diabetes, obesity, heart disease, some types of cancer, birth defects, premature birth, brain disorders, and infertility.

The pieces of plastic themselves can lead to inflammation or damage to our organs, especially if we’re exposed to a lot of them over time. They can also prevent the proper absorption of nutrients from our food.

Because plastic is synthetic, not natural, our bodies don’t know how to break it down. So once it’s in our lungs, blood or tissues, it just stays there. As more arrives, the concentration builds up. This is called bioaccumulation.

In summary, microplastics usually come from bigger pieces of plastic breaking down, and they can get into our bodies through the food we eat, the water we drink, and the air we breathe. Once they are there, we can’t easily get rid of them and they can impact our health in both chemical and physical ways.

This is a really big topic and you’ll find a lot more information and explanation in the reading / watch lists below. Take your time and check out whatever appeals to you. You can also apply your new knowledge in an activity, or test it out in the quiz. If you have any thoughts on plastic and our health, or want to answer the question below, leave us a comment!

Take a look at this:

Did any of the conversation in the video surprise you? Most people are only aware about sea creatures being harmed by plastic, but the reality is a lot worse. Let’s take a look.

HOW EXACTLY DOES PLASTIC HARM NATURE?

As we learned in the first part of our series, plastic is made from fossil fuels and chemicals – and it’s virtually indestructible in natural conditions. It’s exactly these characteristics that make it so dangerous for natural ecosystems and the life within them. Here are the five main ways plastic can harm the living world:

1. Entanglement: Plastic fishing nets, six-pack rings, and shopping bags are all common items that animals can get tangled up in – and there are many more. It’s often hard for them to escape and, aside from causing stress, it can make it difficult or impossible for them to swim, fly, or escape predators. Entanglement can also cause injuries or even death.

2. Ingestion: Many animals, such as sea turtles, birds, and fish, mistake plastic debris for food, either because it looks or smells like what they normally eat. A plastic bag floating underwater can look like a jellyfish, for example. And in the sea, plastic pieces get covered in algae and start to smell like small fish called krill. On land, especially in urban areas, there are other animals who scavenge for food, such as stray dogs, raccoons, monkeys and even elephants or camels. The food they find often gets eaten together with the plastic bags or packaging it comes in. When animals eat any kind of plastic, their digestive systems can get blocked, causing slow starvation. It can also lead to internal injuries and infections.

3. Chemical contamination: The harmful chemicals in plastics can leach out into the environment over time, as they are exposed to sunlight, water and other substances. These chemicals contaminate the water and soil. They can even start to build up in the tissues of animals that eat or come into contact with the plastic. Eventually this will lead to health problems or reproductive issues, as many of the chemicals in plastic affect how hormones function.

4. Habitat destruction: As well as contaminating the soil and water, plastic pollution can smother habitats such as coral reefs, seagrass beds, and wetlands. This suffocates the plant life, which in turn reduces the food and shelter for the various species that live there, leading to an imbalance in the ecosystem and a loss of biodiversity. Healthy ecosystems are essential for supporting human life and reducing climate change, as well as just being wondrous and beautiful parts of our planet.

5. Microplastic ingestion: Once in the environment, larger pieces of plastic break down into smaller fragments called microplastics. These enter the air, soil and water and get eaten or breathed in by a wide range of organisms, from plankton to whales. Microplastics can accumulate in the food chain, potentially reaching levels that can harm animals and humans.

In summary, we might say that plastic is a danger to the living world because it is both synthetic (not occurring in nature) and toxic (containing harmful chemicals). It cannot be broken down by natural processes.

Large pieces of plastic can stop living things and ecosystems from functioning properly from the outside by entangling or suffocating them. Large and small pieces of plastic can also cause damage from the inside either from physically blocking or injuring animals’ digestive systems or through chemical contamination of soil, water, air and living tissue.

To learn more about the impacts of plastics on nature and how they get into the environment in the first place, you’ll find lots of info in the reading / watch lists below. Take your time and check out whatever appeals to you. Some of the videos may feel a bit overwhelming, so take the time to record your thoughts in a journal or video diary – this helps to process any strong feelings. You can also test your knowledge in the quiz. And don’t forget to let us know your thoughts on this topic in the comments.