By Hannah Cooper, Campaign Assistant

When thinking about the global impact of plastic pollution it is important to look at both the visible and hidden effects. We at Final Straw Foundation are extremely conscious of the visible impact of littering and plastic pollution in our oceans, but sometimes it’s easy to separate the litter-strewn oceans and coastline from the ongoing climate crisis. However, the two are more closely linked than you may have thought. Currently, the plastic industry is responsible for a sixth of global carbon emissions and this is only expected to grow- plastic production is expected to triple by 2050. So, what about plastic is so bad for our climate? Plastic actually emits carbon at every stage of its life cycle. Let’s start from the beginning.

First, we need to look at the source of plastic. Conventional plastics are made from crude oil and natural gas, fossil fuels. In fact, 14% of all oil produced each year is used for plastic production. Extracting the fossil fuels that are used in plastic production creates greenhouse gasses before the fossil fuels are even burned. This is due to methane leakage and flaring where the fossil fuels are extracted; the energy used (usually from burning fossil fuels) when drilling; and due to the fact that land that is cleared to drill is damaged and plants there are no longer available to trap carbon dioxide through photosynthesis. The next stage, refining oil through fractional distillation, is extremely energy intensive, requiring the burning of fossil fuels which contributes to the greenhouse effect. The pollution doesn’t stop there. Transport of these raw materials also relies on the combustion of fossil fuels in trucks and lorries, furthering the greenhouse effect. The actual refining of plastic is one of the most greenhouse gas intensive industries in the manufacturing sector, and this is only expected to rise with the increasing popularity of and dependence on plastic. In 2015, globally, plastic manufacturing plants produced as many CO₂ emissions as 45 million passenger vehicles driven for 1 year.

What happens to the plastic once it’s served its purpose? Well, you may be surprised to know that plastic still has a detrimental effect on the climate even after it’s been used. What happens to plastic after you’ve used it is usually up to you. Will you send it to landfill? Drop it on the street? Let it be incinerated? Or does it qualify for recycling? Let’s explore the way plastic effects our climate through these four pathways.

In the UK, 14m tonnes of plastic are sent to landfill annually. This is a staggering statistic. When plastic is sent to landfill, it doesn’t emit as many greenhouse gases as the other three pathways. However, it does have other negative effects on the environment. Rainwater that falls on the landfill collects soluble material from the wate to create Leachate, which runs off into groundwater and, eventually, into the ocean. Plastic that ends up in landfill can expect to be there for a long time. It’s estimated that a single use plastic bottle can take anywhere between 500-1000 years to break down.

If it is not being sent to landfill, plastic that is disposed of in your general waste will be incinerated. The Big Plastic Count, a citizen science project that was conducted this year, found that 46% of plastic household waste is incinerated. This is the case in my home of Portsmouth, where the majority of household waste, including plastic, is incinerated to produce energy for homes in the city. Although this limits the dependence on fossil fuels for energy, incinerating plastic is far from good for our climate, and it has been argued that burning plastic produces more carbon emissions than coal. Burning one tonne of plastic produces nearly two tonnes of CO₂ emissions, which contribute to the greenhouse effect.

As you can see in the data above, 29% of all plastic waste is sent for recycling. It is fantastic that we can turn old materials into new items, however, only a very small fraction of all plastic waste is recycled here in the UK (12%), and the rest gets shipped off to other countries where they have the infrastructure to sort and recycle it. The most environmentally friendly option that you believe you have, recycling plastic, actually is very likely to contribute further to global warming due to the emissions produced when transporting this plastic such a long way. Moreover, plastic is not infinitely recyclable like aluminium, so it will end up along a different path once it has been recycled two or three times, maybe to landfill or incineration, or maybe somewhere else entirely. Keep an eye out for a future blog post on recycling if you would like any more information on this.

As much as we’d like to think everyone is disposing of their plastic waste responsibly, we would be naïve to believe this as true. In fact, we know people aren’t disposing of their waste properly due to the vast amount of plastic waste that we pick up from our shorelines. We are extremely conscious of the effect littering can have on wildlife, from creatures ingesting plastics, to them getting fatally caught and tangled in plastic waste. But what effect does the littering of plastics have on our climate? When plastics break down on the surface of the ocean, albeit over the course of hundreds of years, methane and other greenhouse gases are emitted. And, worryingly, plastics that remain on the shoreline, riverbanks and in terrestrial environments, may release these gases at a higher rate.

There could also be another, hidden effect of plastic on our climate which comes from microplastics. The photosynthesising organisms such as phytoplankton, algae, and kelp in the ocean convert half of the air we breathe from carbon dioxide into oxygen. This means that the ocean is great for capturing and storing atmospheric carbon dioxide. Microplastics in the oceans may be hindering the ability of these organisms to carry out photosynthesis effectively, therefore reducing the amount of atmospheric carbon that can be stored in the ocean. This leads to higher levels of carbon dioxide in our atmosphere which contributes to global warming.

So, what are the solutions? We always encourage the swapping of single-use plastic items with reusable alternatives, and the safe and responsible disposal of any plastic waste. The industry will not continue to grow exponentially if the demand for plastic simply isn’t there, so try and say no to single-use, pointless plastic. Together, through small changes, we can have a big impact.

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